JP4375894B2

JP4375894B2 - Water leakage occurrence position detection device having a correction function and method thereof

Info

Publication number: JP4375894B2
Application number: JP2000312632A
Authority: JP
Inventors: 健荒井
Original assignee: Maeda Corp
Current assignee: Maeda Corp
Priority date: 2000-10-12
Filing date: 2000-10-12
Publication date: 2009-12-02
Anticipated expiration: 2020-10-12
Also published as: JP2002122504A

Description

【０００１】
【発明の属する技術分野】
本発明は、合成樹脂や合成ゴムなどの電気的絶縁性を有する材料からなる遮水膜を敷設して人工的に造られた貯水池、水路、或いは管理型一般廃棄物最終処分場及び管理型産業廃棄物最終処分場などの遮水膜構造物に関し、遮水膜構造物の遮水膜に生じる漏水の発生位置を検知する漏水発生位置検知装置及びその方法に関する。
【０００２】
【従来の技術】
貯水池、水路、或いは管理型一般廃棄物最終処分場及び管理型産業廃棄物最終処分場などの遮水膜構造物は、合成樹脂や合成ゴムなどの電気的絶縁性を有する材料からなる遮水膜を敷設して人工的に造られている。
【０００３】
かかる遮水膜構造物は、遮水膜に亀裂などの破損が生じると、破損箇所より漏水する。例えば、管理型一般廃棄物最終処分場の場合、遮水膜が破損した状態で放置すると、汚染液が漏水して近隣を汚染し、或いは地下水を汚染して公害問題を引き起こしてしまう。そこで、遮水膜を用いた遮水膜構造物は、漏水（あるいは遮水膜の破損）の発生及び発生位置を早期に検知して破損箇所を補修する必要がある。
【０００４】
このような遮水膜構造物の漏水発生位置を検出するために、次のような検知方式が採用されている。この検知方式では、遮水膜の下側に所定の間隔で複数の線状電極を平行に敷設し、遮水膜の上側には下側電極と交差する方向に所定の間隔で複数の線状電極を平行に敷設した電極配置構成を用いる。このような電極配置構成において、遮水膜上下の線状電極を電極セレクタを介して各々１本選択して上下の線状電極間に交流電圧を印加し、上下の線状電極間に流れる電流を検出し、印加電圧の位相に同期した信号で位相検波を行う。そして、上下の線状電極の各々の交点における検出電流の比較から漏水発生位置を検知する。
【０００５】
以下に、この漏水発生位置検知方式の一例を図７を参照して説明する。
この例においては、遮水膜２の上側に線状電極１１₁〜１１₈が配置され、遮水膜２の下側に線状電極１２_A〜１２_Hがそれぞれ配置されている。第１の電極切替器８４には、上側線状電極１１₁〜１１₈のうち１本（図７では上側線状電極１１₃）を選択すると、残りの線状電極は全て共通に接続する機能を持つ電極セレクタが用いられている。第２の電極切替器８５も同様である。
【０００６】
また、信号波形を出力する発振回路８１は電力増幅回路８２に接続され、発振回路８１で作り出された信号波形が電力増幅回路８２によって電力増幅される。電力増幅回路８２は、第１及び第２の電極切替器８４，８５により、上側及び下側の線状電極１１₁〜１１₈，１２_A〜１２_Hとの間で、次のように接続される。
【０００７】
まず、下側線状電極１２_A〜１２_Hにおいては、第２の電極切替器８５で選択された１本の線状電極１２_Cが電力増幅回路８２の出力側の一方に接続され、残りの線状電極１２_A，１２_B，１２_D〜１２_Hは全て電力増幅回路８２の出力側の他方に直接接続される。
【０００８】
次に、上側線状電極１１₁〜１１₈においては、第１の電極切替器８４出力側の他方に、第１の電極切替器８４で選択された１本の線状電極１１₃が電流検出回路８３を介して接続され、残りの線状電極１１₁，１１₂，１１₄〜１１₈は全て電力増幅回路８２の出力側の他方に直接接続される。
【０００９】
その結果、下側線状電極１２_Cから上側線状電極１１₃及び残りの全ての線状電極との間に電流が流れるが、電流検出回路８３では上側線状電極１１₃と下側線状電極１２_Cとの間に流れる電流が検出される。位相検波回路８６は、電力増幅回路８２から出力される印加電圧に同期した位相で電流検出回路８３の位相検波を行う。そして、検出された電流値は、例えばＡ／Ｄコンバータでディジタル信号に変換され、パソコンのようなコンピュータ（何れも図示せず）に与えられ、ＣＲＴ画面等に画像表示される。
【００１０】
このような構成において、遮水膜２に破損がない場合、遮水膜２が電気的絶縁体であるため電流値は検出されない。一方、遮水膜２に破損が生じると、破損個所は電流が流れやすいことから、遮水膜２の上側及び下側線状電極１１₃，１２_Cとの間で電流値が検出される。このことから、上下の線状電極のそれぞれの交点について電流を測定することにより遮水膜２の破損個所を検知することが可能になる。
【００１１】
【発明が解決しようとする課題】
ところで、欧米においては、遮水膜の紫外線劣化や熱劣化を防止するために、土質材料やコンクリートからなる保護層が遮水膜全体に設けられる例が増えている。この保護層は、電気的絶縁体ではないので、遮水膜の上下に線状電極を設置すると、遮水膜上下の線状電極が保護層を経由して遮水膜上下を連絡する短絡回路を形成してしまう。
【００１２】
そして、保護層の電気抵抗値が漏水の電気抵抗値より小さい場合は、保護層を経由して流れる電流が、漏水を経由して流れる電流よりも大きくなる。例えば、上下の線状電極のそれぞれの交点について測定した電流値をＣＲＴ画面等に立体画像で表示すると、図８に示すように、保護層を経由して流れる電流が、漏水を経由して流れる電流よりも大きくなり、また印加電圧と波長及び位相が同じ電流成分であるため、測定した電流値が保護層経由の短絡回路のものか漏水経由のものかの区別がつきにくくなる。なお、図８において、ｘ軸は下側線状電極１２_A〜１２_Hの配置を示し、ｙ軸は上側線状電極１１₁〜１１₈の配置を示し、ｚ軸は電流値を示す。このように、保護層を遮水膜２に設置すると、測定した電流値が保護層経由の短絡回路のものか漏水経由のものかの区別がつきにくく、漏水発生位置を検出する精度を向上させる上での障害となっていた。
【００１３】
以上から本発明は、前記問題点に鑑みてなされたものであり、保護層を経由して流れる電流の特性を把握することにより、漏水に流れる電流のみ抽出する補正を行い、漏水発生位置を検出する精度を向上させる補正機能を有する漏水発生位置検知装置及びその方法を提供することを技術的課題とする。
【００１４】
【課題を解決するための手段】
前記課題を達成するために、本発明の補正機能を有する漏水発生位置検知装置及びその方法は、以下に示す手段を採用した。すなわち、請求項１の補正機能を有する漏水発生位置検知装置は、地盤に形成した窪みに電気的絶縁体の遮水膜を敷設すると共に電気を通す保護層を前記遮水膜上に全面的に層状に設けた遮水膜構造物と、前記遮水膜の上側に平行かつ所定の間隔に並べた複数の上側線状電極と、前記遮水膜を挟んで前記遮水膜の下側に平行かつ前記上側線状電極に交差して所定の間隔に並べた複数の下側線状電極と、前記上側線状電極と前記下側線状電極の１組を選択し、この選択された１組の一方の線状電極を二相交流電源の印加側端子に接続し、選択された１組の他方の線状電極をその二相交流電源の印加側でない他方の端子に接続する選択接続手段と、前記保護層が前記地盤と接触する部分の近傍に配置され、前記二相交流電源の印加側でない他方の端子に接続される環状の補正用電極と、前記選択された１組の線状電極間を流れる第１の電流値を検出する第１電流検出回路と、前記二相交流電源の印加側端子に接続した線状電極と前記環状の補正用電極との間を流れる第２の電流値を検出する第２電流検出回路と、前記選択接続手段が前記上側線状電極と前記下側線状電極の組を順次切り替えることにより前記第１電流検出回路で検出される各第１の電流値、及び、前記第２電流検出回路で検出される各第２の電流値をそれぞれ用いて、各第１の電流値から前記保護層を経由して流れる電流成分がそれぞれ補正された各補正電流値をそれぞれ取得する補正手段と、を備え、前記補正手段により得られた各補正電流値の比較結果と、前記上側線状電極と前記下側線状電極との交差位置と、の関係から前記遮水膜構造物の漏水位置を検知することを特徴とする。
【００１５】
請求項１の発明によれば、選択接続手段により二相交流電源の印加側端子に接続された１本の線状電極（印加電極）と、この印加電極を除く遮水膜上下のすべての線状電極と、環状の補正用電極との間に、(1) 印加電極→地盤→印加電極を除く遮水膜下側のすべての線状電極→印加側でない他方の端子。(2) 印加電極→保護層→補正用電極→第２電流検出回路→印加側でない他方の端子。(3) 印加電極→漏水位置→選択された１本の線状電極→第１電流検出回路→印加側でない他方の端子。(4) 印加電極→保護層→選択された１本の線状電極→第１電流検出回路→印加側でない他方の端子。(5) 印加電極→保護層→選択された１本の線状電極を除く遮水膜上側のすべての線状電極→印加側でない他方の端子、の回路が形成される。そして、回路(3),(4)から検出される第１の電流値は、漏水を経由して流れる電流（回路(3)）と保護層を経由して流れる電流（回路(4)）とが含まれている。一方、回路(2) から検出される第２の電流値は、保護層及び補正用電極を介して流れる電流値であるが、補正用電極が遮水膜構造物周辺の保護層や地盤と接触している部分近くに配置されており、補正用電極が遮水膜上下を短絡する経路を横断する位置にあるため、第２の電流値の傾向は、保護層を経由して流れる電流の傾向とほぼ同一であると考えられる。そこで、保護層を経由して流れる電流の特性を第２電流検出回路により得て、保護層を経由して流れる電流が混入した第１の電流値から、保護層を経由して流れる電流成分を除去し、漏水に関する電流成分のみを抽出するための補正が可能となる。
【００１６】
なお、遮水膜は電気的絶縁性を有する材質である合成樹脂や合成ゴムが例示できる。また、管理型廃棄物最終処分場等に用いられる保護層は、ポリエステルやポリプロピレンの不織布（遮光マット）を敷設する場合や、土質材料やコンクリートを敷設する場合が例示できる。そして、ポリエステルなど合成繊維と比較すると土質材料やコンクリートの方が遮水膜の紫外線劣化や熱劣化防止に好適であり、耐久性において非常に優れた素材であることが知られている。
【００１７】
また、請求項２の補正機能を有する漏水発生位置検知装置は、請求項１の発明の構成において、前記選択接続手段が、前記遮水膜の上下どちらかに設けられた線状電極うちの１本を選んで前記二相交流電源の印加側端子に接続するとともに、前記印加側端子に接続した線状電極以外の前記遮水膜上下に設けられた線状電極及び前記環状の補正用電極を印加側でない他方の端子に接続し、前記遮水膜を挟んで前記印加側端子に接続した線状電極の反対側に設置されている１本の線状電極を選択して前記選択した１組の線状電極とする選択接続機能を有することを特徴とする。
【００１８】
この請求項２の発明によれば、請求項１の発明の作用に加えて、選択接続手段により印加電極を除く全ての線状電極及び環状の補正用電極（すなわち、遮水膜の上下の電場）が、印加側でない他方の端子に接続されることで同電位に制御される。また、遮水膜を挟んで印加電極が反対側に設置された線状電極と環状の補正用電極が印加電極と反対の極性を持ち、また、環状の補正用電極が短絡経路となる保護層内に設けられていること、及び環状の補正用電極が印加電極に近いことから、第１電流検出回路に接続される線状電極群に流れる電流を低減させることができ、結果として保護層の短絡経路を経由して流れる電流を低減させるよう作用する。
【００１９】
更に、請求項３の補正機能を有する漏水発生位置検知装置は、請求項１または請求項２の発明の構成において、前記第１電流検出回路及び／または第２電流検出回路が、前記電源の印加電圧と同波長および同位相の電流成分を抽出する位相検波回路を有することを特徴とする。
【００２０】
請求項３の発明によれば、第１電流検出回路及び／または第２電流検出回路が検出する測定電流値から電源の印加電圧と同波長および同位相の電流成分のみを抽出することで、前記測定電流値から自然電流や高調波ノイズを除去することができる。このことにより、前記測定電流値の精度が向上し、漏水発生位置を検出する精度が向上する。
【００２１】
更にまた、請求項４の補正機能を有する漏水発生位置検知方法は、地盤に形成した窪みに電気的絶縁体の遮水膜を敷設し、電気を通す保護層を前記遮水膜上に全面的に層状に設けて遮水膜構造物を構築し、前記遮水膜の上下に複数の線状電極を並べ、前記保護層が地盤と接触する部分の近傍に環状の補正用電極を配置し、前記遮水膜上下の線状電極の１組を選択して前記選択した１組の線状電極を二相交流電源のいずれかの端子に接続し、前記選択した１組の線状電極間を流れる第１の電流値を検出し、前記二相交流電源の印加側端子に接続した線状電極と前記環状の補正用電極との間を流れる第２の電流値を検出し、前記第２の電流値を用いて前記第１の電流値から前記保護層を経由して流れる電流成分を補正し、前記補正した第１の電流値と前記選択した１組の線状電極の交差位置から前記遮水膜構造物の漏水位置を検知することを特徴とする。
【００２２】
請求項４の発明によれば、保護層を経由して流れる電流の特性を把握することにより、漏水に流れる電流のみ抽出する補正を行い、漏水発生位置を検出する精度を向上させることが可能となる。
【００２３】
以上の発明の構成要件である二相交流電源は、交替直流電源であってもよい。
【００２４】
【発明の実施の形態】
以下、本発明の実施の形態に係る補正機能を有する漏水発生位置検知装置を図１〜図６に基づいて詳細に説明する。なお、実施の形態に係る補正機能を有する漏水発生位置検知装置４は、遮水膜構造物１に設置されている。また、遮水膜構造物１は管理型廃棄物最終処分場の場合として説明する。
【００２５】
遮水膜構造物１は、図１に示すように、窪み１ａに遮水膜２を敷設し、遮水膜２の斜面部に保護層３を積層したものである。そして、遮水膜２は電気的絶縁性を有する合成樹脂で形成されている。また、保護層３は電気的絶縁体でない材料で形成されている。なお、管理型廃棄物最終処分場に用いられる保護層３は、ポリエステルやポリプロピレンの不織布（遮光マット）を敷設する場合や、土質材料やコンクリートを敷設する場合があるが、ポリエステルなど合成繊維と比較すると土質材料やコンクリートの方が遮水膜の紫外線劣化や熱劣化防止に好適であり、耐久性において非常に優れた素材であることが知られている。そこで、この実施の形態では土質材料を敷設したものとして説明する。
【００２６】
また、保護層３は遮水膜構造物１の周囲にわたって積層されており、遮水膜構造物１に敷設した遮水膜２の上面側と下面側とが保護層３を経由して電気的短絡回路が形成可能な状態になっている。
【００２７】
漏水発生位置検知装置４は、図２のブロック回路に示すように、上側線状電極１１₁〜１１₈と下側線状電極１２_A〜１２_Hと環状の補正用電極１３とを有し、上側線状電極１１₁〜１１₈が遮水膜２の上側に複数配置され、下側線状電極１２_A〜１２_Hが遮水膜２の下側に複数配置され、環状の補正用電極１３が上側線状電極１１₁〜１１₈の周囲を取り巻くように遮水膜２の上側に配置されている。そして、上側線状電極１１₁〜１１₈の各々の一端は電極切替器８４に接続され、下側線状電極１２_A〜１２_Hの各々の一端は電極切替器８５に接続されている。
【００２８】
また、漏水発生位置検知装置４は、電力増幅回路１４と発振回路８１を有し、電力増幅回路１４が発振回路８１に接続している。そして、発振回路８１は信号波形を出力し、電力増幅回路１４は発振回路８１で作り出された信号波形を電力増幅する。
【００２９】
電極切替器８４は上側線状電極１１₁〜１１₈のうち１本（図２では上側線状電極１１₃ ）を選択すると残りの線状電極はすべて共通に接続する機能を持つ。すなわち、上側線状電極１１₁〜１１₈においては、電極切替器８４で選択された１本の上側線状電極１１₃ が第１電流検出回路１５を経由して電力増幅回路１４の出力側の他方１４ｂに接続され、残りの上側線状電極１１₁，１１₂，１１₄〜１１₈はすべて共通に電力増幅回路１４の出力側の他方１４ｂに直接接続される。
【００３０】
また、電極切替器８５も下側線状電極１２_A〜１２_Hのうち１本（図２では下側線状電極１２_C ）を選択すると残りの線状電極はすべて共通に接続する機能を持つ。すなわち、下側線状電極１２_A〜１２_Hにおいては、電極切替器８５で選択された１本の下側線状電極１２_C が電力増幅回路１４の出力側の一方１４ａに接続され、残りの下側線状電極１２_A，１２_B，１２_D〜１２_Hはすべて共通に電力増幅回路１４の出力側の他方１４ｂに直接接続される。
【００３１】
また、環状の補正用電極１３は遮水膜２の上側にあって保護層３内に配置されている。そして、環状の補正用電極１３は第２電流検出回路１６を経由して電力増幅回路１４の出力側の他方１４ｂに接続されている。
【００３２】
そして、電力増幅回路１４は、上側及び下側の線状電極１１₁〜１１₈，１２_A〜１２_Hおよび環状の補正用電極１３との間において、電極切替器８４，８５の選択接続により形成される回路に電圧を印加する。
【００３３】
その結果、次のような回路が形成される。なお、遮水膜２には、漏水がＬ１，Ｌ２，Ｌ３（図２参照）の位置で発生しているものとする。
すなわち、(1) 電極切替器８５→下側線状電極１２_C→地盤→下側線状電極１２_A，１２_B，１２_D〜１２_H→電力増幅回路１４の他方１４ｂ。
(2) 電極切替器８５→下側線状電極１２_C→保護層３→補正用電極１３→第２電流検出回路１６→電力増幅回路１４の他方１４ｂ。
(3) 電極切替器８５→下側線状電極１２_C→漏水L1,L2,L3→上側線状電極１２₃→第１電流検出回路１５→電力増幅回路１４の他方１４ｂ。
(4) 電極切替器８５→下側線状電極１２_C→保護層３→上側線状電極１２₃→第１電流検出回路１５→電力増幅回路１４の他方１４ｂ。
(5) 電極切替器８５→下側線状電極１２_C→保護層３→上側線状電極１１₁，１１₂，１１₄〜１１₈→電力増幅回路１４の他方１４ｂ、の回路が形成される。
【００３４】
そして、回路(1)〜(5)によれば、電極切替器８５により選択された１本の下側線状電極（例えば、下側線状電極１２_C）と、下側線状電極１２_Cを除く遮水膜２上下のすべての線状電極と、環状の補正用電極１３との間に電力増幅回路１４の電圧が印加されているので、下側線状電極（印加電極）１２_Cを除く全ての線状電極及び環状の補正用電極１３が、印加側でない他方１４ｂに接続されることで同電位に制御される。従って、漏水発生位置検知装置４は、回路(1)〜(5)が形成されるように構成したことにより、遮水膜２の上下の電場が同電位となるように制御されている。
【００３５】
また、回路(1)〜(5)によれば、遮水膜２を挟んで印加電極１２_Cが反対側に設置された線状電極と環状の補正用電極１３が印加電極１２_Cと反対の極性を持ち、また、環状の補正用電極１３が短絡経路となる保護層３内に設けられていること、及び環状の補正用電極１３が印加電極１２_Cに近いことから、第１電流検出回路１５に接続される線状電極群に流れる電流を低減させることができ、結果として保護層３の短絡経路を経由して流れる電流を低減させるよう作用する。
【００３６】
以上から、回路(1)〜(5)を用い、保護層３を経由して流れる電流の特性を把握することにより、漏水L1,L2,L3に流れる電流成分のみ抽出する補正が可能となる。
【００３７】
ところで、回路(1)〜(5)のうち、電流が検出される回路は(2)〜(4)である。すなわち、回路(2)を経由して流れる電流は第２電流検出回路１６で検出され、回路(3),(4)を経由して流れる電流は第１電流検出回路１５で検出される。
【００３８】
そして、第１電流検出回路１５及び第２電流検出回路１６はそれぞれの位相検波回路１７ａ，１７ｂ及びＡ／Ｄコンバータ１８を介してコンピュータ１９に接続する。位相検波回路１７ａ，１７ｂは、検出した電流値から電力増幅回路１４の印加電圧と同波長及び同位相の電流分を抽出する。言い換えれば、位相検波回路１７ａ，１７ｂは、検出した電流値から電力増幅回路１４の印加電圧と位相の異なる成分（例えば、遮水膜２を介して流れる電流成分）を除去する。従って、この位相検波出力は、電力増幅回路１４の印加電圧と同波長及び同位相の電流分のみがＡ／Ｄコンバータ１８によりデジタル信号に変換され、コンピュータ１９に与えられる。
【００３９】
コンピュータ１９は、双方向バスによって相互に接続されたＲＯＭ（リードオンリメモリ）、ＲＡＭ（ランダムアクセスメモリ）、ＣＰＵ（中央処理装置）、入力ポート、出力ポートを具備する。コンピュータ１９の入力ポートは、Ａ／Ｄコンバータ１８及び位相検波回路１７ａ，１７ｂを介して第１電流検出回路１５及び第２電流検出回路１６と接続し、それぞれの出力信号（測定電流値）が入力される。また、コンピュータ１９の出力ポートは、電極切替器８４，８５と結線し（図示せず）、線状電極の切替の指令を電極切替器８４，８５に対し出力する。なお、線状電極の切替の指令は、後述する選択接続手順に基づき実行される（選択接続手段）。更に、コンピュータ１９の出力ポートは、例えば、ＣＲＴ装置（図示せず）と結線し、ＣＲＴ装置に対し、表示指令（画像データ）を出力する。
【００４０】
ＲＯＭには、漏水発生位置検知処置のプログラムや選択接続手順のプログラムが記憶されており、ＣＰＵはこれらプログラムを読み出して処理を行う。なお、選択接続手順は、電極切替器８４において、第１電流検出回路１５側に接続する端子に上側線状電極１１₁〜１１₈を１個ずつ接続する８種類の手順と、電極切替器８５において、交流電源１４側に接続する端子に下側線状電極１２_A〜１２_Hを１個ずつ接続する８種類の手順とを組み合わせた６４種類を順次切り替える手順である。そして、ＣＰＵは１番目（ｉ＝１；例えば上側線状電極１１₁と下側線状電極１２_Aとの組み合わせ）から６４番目（ｉ＝６４；例えば上側線状電極１１₈と下側線状電極１２_Hとの組み合わせ）をＲＯＭから読み出して電極切替器８４，８５を切り替える指令を出力する。すると、指令順番毎に、上側線状電極と下側線状電極との任意の１組に交流電圧が印加され、これら上下の電極が交差する位置が選択されたことになる。
【００４１】
次に、コンピュータ１９による本発明の漏水発生位置検知処理を図３の流れ図に基づき説明する。
コンピュータ１９は、「ｉ＝１」とし（ステップ１０１）、ＲＯＭに記憶された選択接続手順に従って電極切替器８４，８５の切替を行い、交差位置を選択する（ステップ１０２）。即ち、「ｉ」が１番目の組み合わせ（ｉ＝１；上側線状電極１１₁と下側線状電極１２_Aとの組み合わせ）となるように、電極切替器８４で第１電流検出回路１５と上側線状電極１１₁を接続させ、その他の上側線状電極１１₂〜１１₈を電力増幅回路１４の他方端子１４ｂに接続し、電極切替器８５で電力増幅回路１４の一方端子１４ａと下側線状電極１２_Aを接続させ、その他の下側線状電極１２_B〜１２_Hを電力増幅回路１４の他方端子１４ｂに接続し、電力増幅回路１４の一方端子１４ａと他方端子１４ｂとの間に交流電圧を印加し、これら上下の線状電極が交差する位置を選択する。
【００４２】
この時、漏水発生位置検知装置４には、(1) 電極切替器８５→下側線状電極１２_A→地盤→下側線状電極１２_B〜１２_H→電力増幅回路１４の他方１４ｂ。
(2) 電極切替器８５→下側線状電極１２_A→保護層３→補正用電極１３→第２電流検出回路１６→電力増幅回路１４の他方１４ｂ。
(3) 電極切替器８５→下側線状電極１２_A→漏水L1,L2,L3→上側線状電極１２₁→第１電流検出回路１５→電力増幅回路１４の他方１４ｂ。
(4) 電極切替器８５→下側線状電極１２_A→保護層３→上側線状電極１２₁→第１電流検出回路１５→電力増幅回路１４の他方１４ｂ。
(5) 電極切替器８５→下側線状電極１２_A→保護層３→上側線状電極１１₂〜１１₈→電力増幅回路１４の他方１４ｂ、の回路が形成されている。
【００４３】
そして、第１電流検出回路１５は上記回路(3),(4)の電流値（第１の電流値；Ｉ_1A）を測定し、位相検波回路１７ａ及びＡ／Ｄコンバータ１８を介してコンピュータ１９に出力する。すると、コンピュータ１９は第１の電流値Ｉ_1Aを「ｉ＝１」と共にＲＡＭに記憶する（ステップ１０３）。なお、位相検波回路１７ａは、電力増幅回路１４の印加電圧に同期した位相で検波を行い、電力増幅回路１４の印加電圧と同波長及び同位相の電流分を抽出し、第１の電流値から自然電流や高調波ノイズを除去する。
【００４４】
次に、第２電流検出回路１６は上記回路(2)の電流値（第２の電流値；Ｊ_1A）を測定し、位相検波回路１７ｂ及びＡ／Ｄコンバータ１８を介してコンピュータ１９に出力する。すると、コンピュータ１９は第２の電流値Ｊ_1Aを「ｉ＝１」と共にＲＡＭに記憶する（ステップ１０４）。なお、位相検波回路１７ｂは、位相検波回路１７ａと同様に、電力増幅回路１４の印加電圧に同期した位相で検波を行い、電力増幅回路１４の印加電圧と同波長及び同位相の電流分を抽出し、第２の電流値から自然電流や高調波ノイズを除去する。
【００４５】
次に、コンピュータ１９は、選択切替手順が６４番目（ｉ＝６４；上側線状電極１１₈と下側線状電極１２_Hとの組み合わせ）まで終了したかどうか判断し（ステップ１０５）、ｉ＝６４であれば（ステップ１０５：ＹＥＳ）、ステップ１０７以降の処理を行い。一方、ｉ＝６４でなければ（ステップ１０５：ＮＯ）、ステップ１０６の処理を行う。
【００４６】
ステップ１０６において、コンピュータ１９は、ｉ番目を１だけインクリメントし（ｉ＝ｉ＋１）、ステップ１０２以降の処理を繰り返す。すなわち、コンピュータ１９は、「ｉ＝１」から「ｉ＝６４」までの処理で検出された第１の電流値及び第２の電流値をそれぞれ記憶する。
【００４７】
ステップ１０７において、コンピュータ１９は、ＲＡＭ内に記憶された第１の電流値及び第２の電流値に基づき保護層３を経由して流れる電流の補正処理を行う（補正手段）。次に、この補正処理を説明する。なお、説明の都合上、第１の電流値をＩxy、第２の電流値をＪxyと表現し、第１の電流値の全測定値の最大値をＩmax、第２の電流値の全測定値の最大値をＪmaxと表現する。また、Ｉ，Ｊの添え字「x」は、図２における「₁」〜「₈」を示し、添え字「y」は、「_A」〜「_H」を示す。
【００４８】
［補正処理の説明］
第１の電流値Ｉxyは、漏水を経由して流れる電流（回路(3)）と保護層３を経由して流れる電流（回路(4)）とが含まれている。例えば、漏水発生位置検知処理のステップ１０３において測定した第１の電流値Ｉxyの測定結果を１番目から６４番目まで立体図で表示すると、図４に示す測定結果となる。なお、図４に示すｘ軸は下側線状電極１２_A〜１２_Hの配置を示し、ｙ軸は上側線状電極１１₁〜１１₈の配置を示し、ｚ軸は電流値を示す。図４から第１の電流値Ｉxyの測定結果は、漏水を経由して流れる電流値と保護層３を経由して流れる電流値とが含まれていることを示している。また、この実施の形態において環状の補正用電極１３を設けたことにより、遮水膜２の上下の電場が同電位となるように制御されるため、従来の図８に示す立体図に比して図４に示す立体図のものは、保護層３を経由して流れる電流が低減することがわかる。しかし、これだけでは保護層３を経由して流れる電流の影響を除去できない。
【００４９】
一方、第２の電流値Ｊxyは、保護層３を経由して流れる電流（回路(4)）である。例えば、漏水発生位置検知処理のステップ１０４において測定した第２の電流値Ｊxyの測定結果を１番目から６４番目まで第２の電流値単独で立体図で表示すると、図５に示す測定結果となる。なお、図５に示すｘ軸、ｙ軸、ｚ軸は図４の場合と同様である。図５から第２の電流値Ｊxyの測定結果は、電流検出回路１５で測定された第１の電流値Ｉxyの測定結果（図４参照）の傾向と非常に似ており、電流は保護層３に流れる電流が大きいことを示している。なお、第２の電流値Ｊxyは、補正用電極１３を介して測定されるもの（回路(2)）であるが、補正用電極１３が遮水膜構造物１周辺の保護層３や地盤と接触している部分近くに配置されているため、第２の電流値Ｊxyの傾向は、保護層３を経由して流れる電流の傾向とほぼ同一であると考えられる。
【００５０】
そこで、コンピュータ１９は、数式１に示すように、ＲＡＭに記憶された第１電流値Ｉxy及び第２電流値Ｊxyと、６４回測定したそれぞれの最大値Ｉmax，Ｊmaxを求めて、第１電流値及び第２電流値を正規化し、それぞれを差し引くことにより補正後の測定値Ｋxyを求める。
Ｋxy＝Ｉxy／Ｉmax−Ｊxy／Ｊmax …数式１
【００５１】
そして、コンピュータ１９は、補正後の測定値Ｋxyを「ｉ＝１」から「ｉ＝６４」まで交差位置「ｉ」毎に求め、ＲＡＭに記憶する。ところで、数式１は、無次元数で表示されるが、下記に示す数式２を用いれば電流のオーダーを持つ補正結果Ｌxyが得られる。
Ｌxy＝Ｉmax＊［Ｉxy／Ｉmax−Ｊxy／Ｊmax］ …数式２
【００５２】
次に、コンピュータ１９は、補正後の測定値Ｋxy（あるいは補正結果Ｌxy）をＣＲＴ画面に表示する指令をＣＲＴ装置へ出力する（ステップ１０８）。すると、ＣＲＴ装置はＣＲＴ画面の交差位置に「ｉ＝１」から「ｉ＝６４」までの測定値Ｋxyを表示する。
【００５３】
そこで、環状の補正用電極１３の電流測定結果を用いて、第１電流値Ｉxyを補正し、補正後の測定値Ｋxyに基づき表示すると、図６に示す立体図となる。なお、図６に示すｘ軸、ｙ軸、ｚ軸は図４の場合と同様である。このようにステップ１０７の補正処理により、保護層３を経由して流れる電流の影響が完全に除去でき、漏水箇所が明瞭となる立体図となることが分かる。
【００５４】
すなわち、遮水膜２の上側及び下側線状電極（１１₃と１１_C、１１₇と１１_C、１１₇と１１_H）の交点Ｌ１，Ｌ２，Ｌ３（図２参照）に漏水が発生している場合、補正した第１の電流値を表示すれば、図６の立体図に示すように、遮水膜２の破損個所Ｌ１，Ｌ２，Ｌ３に近い電極の組み合わせ交点が大きい値を示し、遮水膜２の破損個所Ｌ１，Ｌ２，Ｌ３から電極の組み合わせ交点が離れるに従って第１の電流値が小さくなる傾向が表示されることになり、漏水発生位置Ｌ１，Ｌ２，Ｌ３を知ることが可能となる。
【００５５】
そして、コンピュータ１９は、ＣＲＴ画面に測定値Ｋxyが表示されれば、漏水発生位置検知処理を終了する。
【００５６】
上述の電流値補正例のように、この実施の形態によれば、保護層３を経由して流れる電流の特性を環状の補正用電極１３を用いて把握することにより、漏水を経由して流れる電流（回路(3)）のみ抽出する補正を行い、漏水発生位置を検知するように構成した。従って、遮水膜２が破損して位置Ｌ１，Ｌ２，Ｌ３で漏水が発生した場合、漏水を経由して流れる電流のみ抽出できるので、漏水発生位置Ｌ１，Ｌ２，Ｌ３に近い線状電極の組み合わせ（１１₃と１１_C、１１₇と１１_C、１１₇と１１_H）の間を流れる電流値が他の電極間の電流値よりも上昇することが明瞭に検知でき、漏水発生位置Ｌ１，Ｌ２，Ｌ３の検出精度が向上する。
【００５７】
なお、この実施の形態では、漏水発生位置を検知する測定対象を電流値として説明したが、この発明の測定対象は電流値以外に、測定電流値と印加電圧から求まる電気抵抗値であってもよい。
【００５８】
また、この実施の形態では電源を発振回路８１の信号波形を電力増幅回路１４で増幅する二相交流電源として説明したが、電源は交替直流の電源でもよい。また、電源の一端を図２では、遮水膜の地盤側に設置した場合で説明したが、原理的に処分場内の電極であってもよい。
【００５９】
【発明の効果】
本発明によれば、第２電流検出回路で測定された補正用電極に流れる第２の電流値と第１電流検出回路で測定された第１の電流値を、それぞれの測定値の最大値で正規化し、それぞれの差をとることにより、保護層を経由して流れる電流の影響を除去できる。
【００６０】
また、本発明によれば、補正用電極を用いて遮水膜の電位を基本的に同一にするように構成したので、漏水に流れる電流を他の漏水や保護層に流れる電流の影響を受けずに明確に捉えることができる。
【００６１】
更に、本発明によれば、土質材料を用いた保護層が遮水膜全面に設けられた条件でも、補正用電極によって保護層を経由して流れる電流の影響を低減することができる。
【００６２】
従って、本発明は保護層を経由して流れる電流の特性を把握することにより、漏水に流れる電流のみ抽出する補正を行い、漏水発生位置を検出する精度を向上させる補正機能を有する漏水発生位置検知装置及びその方法を提供することができる。
【図面の簡単な説明】
【図１】遮水膜構造物の側断面図であり、保護層を経由して電流が流れる状態を示している。
【図２】本発明の漏水発生位置検知装置のブロック回路図である。
【図３】本発明の漏水発生位置検出処理の流れ図である。
【図４】第１の電流値の測定結果を表示した立体図である。
【図５】第２の電流値の測定結果を表示した立体図である。
【図６】補正用電極を用いて、図４の測定結果を補正した場合の立体図である。
【図７】従来の漏水発生位置検知装置のブロック回路図である。
【図８】補正用電極を作動させなかった場合における測定結果の立体図である。
【符号の説明】
１…遮水膜構造物
１ａ…窪み
２…遮水膜
３…保護層
１１₁〜１１₈…上側線状電極
１２_A〜１２_H…下側線状電極
１３…環状の補正用電極
１４…電力増幅回路（二相交流電源）
１５…第１電流検出回路
１６…第２電流検出回路
１７ａ，１７ｂ…位相検波回路
１８…Ａ／Ｄコンバータ
１９…コンピュータ（補正手段）
８１…発振回路
８４，８５…電極切替器（選択接続手段）[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a reservoir, waterway, or managed municipal waste final disposal site and managed industrial that is artificially constructed by laying a water shielding film made of an electrically insulating material such as synthetic resin or synthetic rubber. The present invention relates to a water leakage occurrence position detection apparatus and a method for detecting a leakage occurrence position of a water leakage generated in a water shielding film of a water shielding film structure, for a water shielding film structure such as a waste final disposal site.
[0002]
[Prior art]
Water-blocking membrane structures such as reservoirs, watercourses, managed municipal waste final disposal sites, and managed industrial waste final disposal sites are made of electrically insulating materials such as synthetic resins and synthetic rubber. Is artificially constructed.
[0003]
Such a water-blocking film structure leaks water from the damaged portion when a breakage such as a crack occurs in the water-blocking film. For example, tube In the case of a physical waste disposal site, if the water shielding film is left in a damaged state, the contaminated liquid leaks and contaminates the neighborhood, or contaminates the groundwater and causes pollution problems. Therefore, it is necessary to repair the damaged part by detecting the occurrence and location of water leakage (or breakage of the water shielding film) at an early stage in the water shielding film structure using the water shielding film.
[0004]
In order to detect the water leakage occurrence position of such a water shielding film structure, the following detection method is employed. In this detection method, a plurality of linear electrodes are laid in parallel at a predetermined interval on the lower side of the water shielding film, and a plurality of linear electrodes are arranged on the upper side of the water shielding film at a predetermined interval in a direction intersecting the lower electrode. An electrode arrangement configuration in which electrodes are laid in parallel is used. In such an electrode arrangement configuration, one of the upper and lower linear electrodes is selected via the electrode selector, an AC voltage is applied between the upper and lower linear electrodes, and the current flowing between the upper and lower linear electrodes. , And phase detection is performed using a signal synchronized with the phase of the applied voltage. And a water leak generation | occurrence | production position is detected from the comparison of the detection electric current in each intersection of an upper and lower linear electrode.
[0005]
Below, an example of this water leak generation | occurrence | production position detection system is demonstrated with reference to FIG.
In this example, the linear electrode 11 is disposed on the upper side of the water shielding film 2. ₁ ~ 11 ₈ Is disposed, and the linear electrode 12 is provided below the water-shielding film 2. _A ~ 12 _H Are arranged respectively. The first electrode switch 84 includes an upper linear electrode 11. ₁ ~ 11 ₈ 1 (in FIG. 7, the upper linear electrode 11) _Three ) Is used, an electrode selector having a function of connecting all the remaining linear electrodes in common is used. The same applies to the second electrode switch 85.
[0006]
The oscillation circuit 81 that outputs a signal waveform is connected to a power amplification circuit 82, and the signal waveform generated by the oscillation circuit 81 is power amplified by the power amplification circuit 82. The power amplification circuit 82 is connected to the upper and lower linear electrodes 11 by the first and second electrode switchers 84 and 85. ₁ ~ 11 ₈ , 12 _A ~ 12 _H Are connected as follows.
[0007]
First, the lower linear electrode 12 _A ~ 12 _H , One linear electrode 12 selected by the second electrode switch 85 is used. _C Is connected to one of the output sides of the power amplifier circuit 82 and the remaining linear electrodes 12 are connected. _A , 12 _B , 12 _D ~ 12 _H Are all directly connected to the other output side of the power amplifier circuit 82.
[0008]
Next, the upper linear electrode 11 ₁ ~ 11 ₈ , The other linear electrode 11 selected by the first electrode switch 84 is provided on the other output side of the first electrode switch 84. _Three Are connected via the current detection circuit 83 and the remaining linear electrodes 11 are connected. ₁ , 11 ₂ , 11 _Four ~ 11 ₈ Are all directly connected to the other output side of the power amplifier circuit 82.
[0009]
As a result, the lower linear electrode 12 _C To upper linear electrode 11 _Three Current flows between all of the remaining linear electrodes and the upper linear electrode 11 in the current detection circuit 83. _Three And lower linear electrode 12 _C Is detected. The phase detection circuit 86 performs phase detection of the current detection circuit 83 with a phase synchronized with the applied voltage output from the power amplification circuit 82. The detected current value is converted into a digital signal by an A / D converter, for example, and is supplied to a computer (not shown) such as a personal computer, and an image is displayed on a CRT screen or the like.
[0010]
In such a configuration, when the water shielding film 2 is not damaged, the current value is not detected because the water shielding film 2 is an electrical insulator. On the other hand, when breakage occurs in the water-shielding film 2, current flows easily through the broken portions, and therefore the upper and lower linear electrodes 11 of the water-shielding film 2. _Three , 12 _C A current value is detected between and. From this, it becomes possible to detect the damaged portion of the water-shielding film 2 by measuring the current at each intersection of the upper and lower linear electrodes.
[0011]
[Problems to be solved by the invention]
By the way, in Europe and the United States, in order to prevent ultraviolet ray deterioration and heat deterioration of a water shielding film, an example in which a protective layer made of a soil material or concrete is provided on the entire water shielding film is increasing. Since this protective layer is not an electrical insulator, when linear electrodes are installed above and below the water barrier film, the linear electrodes above and below the water barrier film connect the upper and lower surfaces of the water barrier film via the protective layer. Will be formed.
[0012]
And when the electrical resistance value of a protective layer is smaller than the electrical resistance value of water leakage, the electric current which flows through a protective layer becomes larger than the electric current which flows through water leakage. For example, when the current values measured at the intersections of the upper and lower linear electrodes are displayed as a stereoscopic image on a CRT screen or the like, the current flowing through the protective layer flows through the water leakage as shown in FIG. Since the applied voltage, wavelength, and phase are the same current component, it becomes difficult to distinguish whether the measured current value is from a short circuit via a protective layer or from water leakage. In FIG. 8, the x-axis is the lower linear electrode 12. _A ~ 12 _H Where the y-axis is the upper linear electrode 11 ₁ ~ 11 ₈ The z-axis indicates the current value. As described above, when the protective layer is installed on the water shielding film 2, it is difficult to distinguish whether the measured current value is that of the short circuit via the protective layer or that of the water leak, and the accuracy of detecting the position of the water leak is improved. It was an obstacle in the above.
[0013]
From the above, the present invention has been made in view of the above problems, and by grasping the characteristics of the current flowing through the protective layer, it corrects to extract only the current flowing in the water leak, and detects the position where the water leak has occurred. It is an object of the present invention to provide a water leakage occurrence position detection device having a correction function for improving accuracy and a method thereof.
[0014]
[Means for Solving the Problems]
In order to achieve the above object, the water leak occurrence position detecting device having the correction function of the present invention and the method thereof employ the following means. In other words, the water leak occurrence position detecting device having the correction function according to claim 1 lays a water shielding film of an electrical insulator in a depression formed in the ground and a protective layer for conducting electricity entirely on the water shielding film. A layer of a water shielding film structure, a plurality of upper linear electrodes arranged in parallel and at a predetermined interval above the water shielding film, and parallel to the lower side of the water shielding film with the water shielding film interposed therebetween And a plurality of lower linear electrodes that intersect the upper linear electrodes and are arranged at a predetermined interval; ,in front Select one set of the upper linear electrode and the lower linear electrode, This selected A set of One The linear electrode is connected to the two-phase AC power supply. Connect to the application side terminal and connect the other set of the other linear electrodes to the other side that is not the application side of the two-phase AC power supply Selective connection means for connecting to the terminals of An annular correction electrode connected to the other terminal that is not on the application side of the two-phase AC power source, the protective layer being disposed in the vicinity of the portion in contact with the ground; The selection Is A first current detection circuit for detecting a first current value flowing between the pair of linear electrodes, and between the linear electrode connected to the application side terminal of the two-phase AC power source and the annular correction electrode A second current detection circuit for detecting a second current value flowing through The first connection value detected by the first current detection circuit and the second current detection circuit are detected by the selective connection means by sequentially switching the pair of the upper and lower linear electrodes. Each of the second current values to be used, and each first current value Current component flowing through the protective layer from Acquire each corrected current value corrected by Correction means, Comparison result of each correction current value obtained by the correction means, and the upper linear electrode and the lower linear electrode Intersection position And the relationship The water leakage position of the water shielding film structure is detected.
[0015]
According to the first aspect of the present invention, one linear electrode (applied electrode) connected to the application side terminal of the two-phase AC power supply by the selective connection means, and all lines above and below the water shielding film excluding the applied electrode (1) Applied electrode → Ground → All linear electrodes under the water shielding film except the applied electrode → the other terminal that is not the applied side. (2) Application electrode → Protection layer → Correction electrode → Second current detection circuit → The other terminal not on the application side. (3) Application electrode → water leakage position → one selected linear electrode → first current detection circuit → the other terminal not on the application side. (4) Applied electrode → Protective layer → Selected one linear electrode → First current detection circuit → The other terminal not on the applied side. (5) A circuit is formed of the application electrode → the protective layer → all the linear electrodes on the upper side of the water shielding film except for one selected linear electrode → the other terminal not on the application side. The first current value detected from the circuits (3) and (4) is the current flowing through the water leak (circuit (3)) and the current flowing through the protective layer (circuit (4)). It is included. On the other hand, the second current value detected from the circuit (2) is a current value flowing through the protective layer and the correction electrode, but the correction electrode is in contact with the protective layer and the ground around the water shielding film structure. Since the correction electrode is located at a position that crosses the path that short-circuits the upper and lower surfaces of the water shielding film, the second current value tends to tend to flow through the protective layer. Is considered to be almost the same. Therefore, the characteristics of the current flowing through the protective layer are obtained by the second current detection circuit, and the current component flowing through the protective layer is obtained from the first current value in which the current flowing through the protective layer is mixed. Correction for removing and extracting only the current component related to water leakage is possible.
[0016]
The water shielding film can be exemplified by a synthetic resin or a synthetic rubber which is a material having electrical insulation. Moreover, the protective layer used for the management-type waste final disposal site etc. can illustrate the case where the nonwoven fabric (light-shielding mat) of polyester or a polypropylene is laid, or the case where a soil material or concrete is laid. And, compared with synthetic fibers such as polyester, soil materials and concrete are known to be more suitable for preventing UV deterioration and thermal deterioration of the water shielding film, and are extremely excellent in durability.
[0017]
According to a second aspect of the present invention, there is provided the water leakage occurrence position detecting device according to the first aspect of the invention, wherein the selective connecting means is one of the linear electrodes provided on either the upper or lower side of the water shielding film. A book is selected and connected to the application side terminal of the two-phase AC power supply, and the linear electrodes provided above and below the water shielding film other than the linear electrode connected to the application side terminal and the annular correction electrode are provided. Connected to the other terminal that is not the application side, and selects the one set of linear electrodes that are installed on the opposite side of the linear electrode that is connected to the application side terminal with the water shielding film interposed therebetween. It has a selective connection function as a linear electrode.
[0018]
According to the second aspect of the invention, in addition to the action of the first aspect of the invention, all the linear electrodes and the annular correction electrodes except the applied electrode by the selective connection means (that is, the electric fields above and below the water shielding film). ) Is connected to the other terminal which is not the application side, and is controlled to the same potential. In addition, a linear electrode in which the application electrode is placed on the opposite side across the water-shielding film and the annular correction electrode have a polarity opposite to that of the application electrode, and the annular correction electrode serves as a short circuit path Since the annular correction electrode is close to the application electrode, the current flowing through the linear electrode group connected to the first current detection circuit can be reduced, and as a result, the protective layer It acts to reduce the current flowing through the short circuit path.
[0019]
Furthermore, the water leakage occurrence position detecting device having the correction function according to claim 3 is the configuration of the invention according to claim 1 or claim 2, wherein the first current detection circuit and / or the second current detection circuit is configured to apply the power supply. It has a phase detection circuit that extracts a current component having the same wavelength and the same phase as the voltage.
[0020]
According to the invention of claim 3, by extracting only the current component having the same wavelength and the same phase as the applied voltage of the power source from the measured current value detected by the first current detection circuit and / or the second current detection circuit, Natural current and harmonic noise can be removed from the measured current value. Thereby, the accuracy of the measured current value is improved, and the accuracy of detecting the water leakage occurrence position is improved.
[0021]
Furthermore, in the water leak occurrence position detecting method having a correction function according to claim 4, a water shielding film of an electrical insulator is laid in a recess formed in the ground, and a protective layer for conducting electricity is entirely formed on the water shielding film. Providing a layer of a water shielding film structure, arranging a plurality of linear electrodes above and below the water shielding film, and arranging an annular correction electrode in the vicinity of the portion where the protective layer contacts the ground, Select one set of linear electrodes above and below the water shielding film, connect the selected set of linear electrodes to any terminal of a two-phase AC power source, and connect the selected set of linear electrodes between the selected linear electrodes A first current value that flows is detected, a second current value that flows between the linear electrode connected to the application side terminal of the two-phase AC power supply and the annular correction electrode is detected, and the second current value is detected. Using the current value, the current component flowing through the protective layer is corrected from the first current value, and the corrected first current is corrected. And detecting a water leakage position of the Saegimizumaku structure from the intersection of the selected pair of linear electrodes and.
[0022]
According to the invention of claim 4, by grasping the characteristics of the current flowing through the protective layer, it is possible to perform correction for extracting only the current flowing through the water leakage, and to improve the accuracy of detecting the water leakage occurrence position. Become.
[0023]
The two-phase AC power supply that is a constituent element of the above invention may be an alternating DC power supply.
[0024]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a water leakage occurrence position detection device having a correction function according to an embodiment of the present invention will be described in detail with reference to FIGS. In addition, the water leak generation | occurrence | production position detection apparatus 4 which has the correction function which concerns on embodiment is installed in the water-blocking film structure 1. FIG. Further, the water shielding film structure 1 will be described as a case of a managed waste final disposal site.
[0025]
As shown in FIG. 1, the water-blocking film structure 1 is formed by laying a water-blocking film 2 in a recess 1 a and laminating a protective layer 3 on a slope portion of the water-blocking film 2. The water shielding film 2 is formed of a synthetic resin having electrical insulation. The protective layer 3 is made of a material that is not an electrical insulator. The protective layer 3 used in the final disposal site for managed waste may be laid with polyester or polypropylene non-woven fabric (light-shielding mat), or with soil materials or concrete, but compared with synthetic fibers such as polyester. Then, it is known that soil materials and concrete are more suitable for preventing UV degradation and thermal degradation of the water shielding film, and are extremely excellent in durability. Therefore, in this embodiment, description will be made assuming that a soil material is laid.
[0026]
Further, the protective layer 3 is laminated around the periphery of the water shielding film structure 1, and the upper surface side and the lower surface side of the water shielding film 2 laid on the water shielding film structure 1 are electrically connected via the protective layer 3. A short circuit can be formed.
[0027]
As shown in the block circuit of FIG. ₁ ~ 11 ₈ And lower linear electrode 12 _A ~ 12 _H And an annular correction electrode 13, and the upper linear electrode 11. ₁ ~ 11 ₈ Are arranged on the upper side of the water shielding film 2, and the lower linear electrode 12 _A ~ 12 _H Are arranged below the water-impervious film 2, and the annular correction electrode 13 is the upper linear electrode 11. ₁ ~ 11 ₈ It is arrange | positioned above the water-impervious film 2 so that the circumference | surroundings may be surrounded. And the upper side linear electrode 11 ₁ ~ 11 ₈ One end of each is connected to the electrode switch 84 and the lower linear electrode 12 is connected. _A ~ 12 _H One end of each is connected to the electrode switch 85.
[0028]
The water leakage occurrence position detection device 4 includes a power amplification circuit 14 and an oscillation circuit 81, and the power amplification circuit 14 is connected to the oscillation circuit 81. The oscillation circuit 81 outputs a signal waveform, and the power amplification circuit 14 amplifies the signal waveform produced by the oscillation circuit 81.
[0029]
The electrode switch 84 is connected to the upper linear electrode 11. ₁ ~ 11 ₈ 1 (in FIG. 2, the upper linear electrode 11) _Three ) Has the function of connecting all the remaining linear electrodes in common. That is, the upper linear electrode 11 ₁ ~ 11 ₈ , One upper linear electrode 11 selected by the electrode switch 84 is used. _Three Is connected to the other output side 14b of the power amplifier circuit 14 via the first current detection circuit 15, and the remaining upper linear electrode 11 is connected. ₁ , 11 ₂ , 11 _Four ~ 11 ₈ Are connected directly to the other output 14b of the power amplifier circuit 14 in common.
[0030]
The electrode switch 85 also has the lower linear electrode 12. _A ~ 12 _H 1 (in FIG. 2, the lower linear electrode 12) _C ) Has the function of connecting all the remaining linear electrodes in common. That is, the lower linear electrode 12 _A ~ 12 _H , One lower linear electrode 12 selected by the electrode switch 85 is used. _C Is connected to the output side 14a of the power amplifier circuit 14, and the remaining lower linear electrode 12 is _A , 12 _B , 12 _D ~ 12 _H Are connected directly to the other output 14b of the power amplifier circuit 14 in common.
[0031]
In addition, the annular correction electrode 13 is disposed on the upper side of the water shielding film 2 and in the protective layer 3. The annular correction electrode 13 is connected to the other output side 14 b of the power amplifier circuit 14 via the second current detection circuit 16.
[0032]
The power amplification circuit 14 includes the upper and lower linear electrodes 11. ₁ ~ 11 ₈ , 12 _A ~ 12 _H A voltage is applied to the circuit formed by the selective connection of the electrode switches 84 and 85 between the annular correction electrode 13.
[0033]
As a result, the following circuit is formed. It is assumed that water leakage occurs in the water shielding film 2 at positions L1, L2, and L3 (see FIG. 2).
(1) Electrode switch 85 → lower linear electrode 12 _C → Ground → Lower linear electrode 12 _A , 12 _B , 12 _D ~ 12 _H → The other 14 b of the power amplifier circuit 14.
(2) Electrode switch 85 → lower linear electrode 12 _C → Protective layer 3 → correction electrode 13 → second current detection circuit 16 → the other 14 b of the power amplification circuit 14.
(3) Electrode switch 85 → lower linear electrode 12 _C → Leakage L1, L2, L3 → Upper linear electrode 12 _Three → the first current detection circuit 15 → the other 14 b of the power amplification circuit 14.
(4) Electrode switch 85 → lower linear electrode 12 _C → protective layer 3 → upper linear electrode 12 _Three → the first current detection circuit 15 → the other 14 b of the power amplification circuit 14.
(5) Electrode switch 85 → lower linear electrode 12 _C → protective layer 3 → upper linear electrode 11 ₁ , 11 ₂ , 11 _Four ~ 11 ₈ → A circuit of the other 14b of the power amplifier circuit 14 is formed.
[0034]
According to the circuits (1) to (5), one lower linear electrode selected by the electrode switch 85 (for example, the lower linear electrode 12). _C ) And the lower linear electrode 12 _C Since the voltage of the power amplifying circuit 14 is applied between all the linear electrodes above and below the water shielding film 2 except for and the annular correction electrode 13, the lower linear electrode (application electrode) 12 _C All the linear electrodes except for and the annular correction electrode 13 are controlled to the same potential by being connected to the other 14b which is not the application side. Therefore, the water leak occurrence position detection device 4 is controlled so that the electric fields above and below the water shielding film 2 have the same potential by configuring the circuits (1) to (5).
[0035]
Further, according to the circuits (1) to (5), the application electrode 12 with the water shielding film 2 interposed therebetween. _C Are arranged on the opposite side, and a linear correction electrode 13 and an application electrode 12 _C The annular correction electrode 13 is provided in the protective layer 3 serving as a short circuit path, and the annular correction electrode 13 is applied to the application electrode 12. _C Therefore, the current flowing through the linear electrode group connected to the first current detection circuit 15 can be reduced, and as a result, the current flowing through the short-circuit path of the protective layer 3 is reduced.
[0036]
From the above, by using the circuits (1) to (5) and grasping the characteristics of the current flowing through the protective layer 3, it is possible to perform correction for extracting only the current components flowing in the water leaks L1, L2, and L3.
[0037]
By the way, among the circuits (1) to (5), the circuits from which current is detected are (2) to (4). That is, the current flowing through the circuit (2) is detected by the second current detection circuit 16, and the current flowing through the circuits (3) and (4) is detected by the first current detection circuit 15.
[0038]
The first current detection circuit 15 and the second current detection circuit 16 are connected to the computer 19 via the phase detection circuits 17a and 17b and the A / D converter 18, respectively. The phase detection circuits 17a and 17b extract a current component having the same wavelength and the same phase as the applied voltage of the power amplifier circuit 14 from the detected current value. In other words, the phase detection circuits 17a and 17b remove components having different phases from the applied voltage of the power amplifier circuit 14 (for example, current components flowing through the water shielding film 2) from the detected current value. Therefore, only the current having the same wavelength and the same phase as the applied voltage of the power amplifier circuit 14 is converted into a digital signal from the phase detection output by the A / D converter 18 and supplied to the computer 19.
[0039]
The computer 19 includes a ROM (Read Only Memory), a RAM (Random Access Memory), a CPU (Central Processing Unit), an input port, and an output port that are connected to each other via a bidirectional bus. The input port of the computer 19 is connected to the first current detection circuit 15 and the second current detection circuit 16 via the A / D converter 18 and the phase detection circuits 17a and 17b, and the respective output signals (measured current values) are input. Is done. Further, the output port of the computer 19 is connected to the electrode switchers 84 and 85 (not shown) and outputs a command for switching the linear electrodes to the electrode switchers 84 and 85. The command for switching the linear electrodes is executed based on a selection connection procedure described later (selection connection means). Further, the output port of the computer 19 is connected to, for example, a CRT device (not shown) and outputs a display command (image data) to the CRT device.
[0040]
The ROM stores a program for detecting a leakage occurrence position and a program for a selective connection procedure, and the CPU reads these programs and performs processing. Note that the selective connection procedure is such that, in the electrode switch 84, the upper linear electrode 11 is connected to the terminal connected to the first current detection circuit 15 side. ₁ ~ 11 ₈ In the electrode switching device 85, the lower linear electrode 12 is connected to the terminal connected to the AC power supply 14 side. _A ~ 12 _H This is a procedure for sequentially switching 64 types, which is a combination of 8 types of procedures for connecting one by one. The CPU is first (i = 1; for example, the upper linear electrode 11 ₁ And lower linear electrode 12 _A 64) (i = 64; for example, upper linear electrode 11) ₈ And lower linear electrode 12 _H Is read from the ROM, and a command to switch the electrode switches 84 and 85 is output. Then, for each command order, an AC voltage is applied to an arbitrary set of the upper linear electrode and the lower linear electrode, and a position where these upper and lower electrodes intersect is selected.
[0041]
Next, the leak detection position detection process of the present invention by the computer 19 will be described based on the flowchart of FIG.
The computer 19 sets “i = 1” (step 101), switches the electrode switches 84 and 85 according to the selection connection procedure stored in the ROM, and selects the crossing position (step 102). That is, “i” is the first combination (i = 1; upper linear electrode 11 ₁ And lower linear electrode 12 _A The first current detection circuit 15 and the upper linear electrode 11 by the electrode switch 84. ₁ Other upper linear electrodes 11 ₂ ~ 11 ₈ Is connected to the other terminal 14b of the power amplifier circuit 14, and one electrode 14a of the power amplifier circuit 14 and the lower linear electrode 12 are connected by the electrode switch 85. _A And the other lower linear electrode 12 _B ~ 12 _H Is connected to the other terminal 14b of the power amplifier circuit 14, an AC voltage is applied between the one terminal 14a and the other terminal 14b of the power amplifier circuit 14, and the position where the upper and lower linear electrodes intersect is selected.
[0042]
At this time, the leak detection position detection device 4 includes (1) electrode switch 85 → lower linear electrode 12. _A → Ground → Lower linear electrode 12 _B ~ 12 _H → The other 14 b of the power amplifier circuit 14.
(2) Electrode switch 85 → lower linear electrode 12 _A → Protective layer 3 → correction electrode 13 → second current detection circuit 16 → the other 14 b of the power amplification circuit 14.
(3) Electrode switch 85 → lower linear electrode 12 _A → Leakage L1, L2, L3 → Upper linear electrode 12 ₁ → the first current detection circuit 15 → the other 14 b of the power amplification circuit 14.
(4) Electrode switch 85 → lower linear electrode 12 _A → protective layer 3 → upper linear electrode 12 ₁ → the first current detection circuit 15 → the other 14 b of the power amplification circuit 14.
(5) Electrode switch 85 → lower linear electrode 12 _A → protective layer 3 → upper linear electrode 11 ₂ ~ 11 ₈ → A circuit of the other 14b of the power amplifier circuit 14 is formed.
[0043]
Then, the first current detection circuit 15 has the current values (first current values; I) of the circuits (3) and (4). _1A ) And is output to the computer 19 via the phase detection circuit 17a and the A / D converter 18. Then, the computer 19 uses the first current value I. _1A Is stored in the RAM together with “i = 1” (step 103). The phase detection circuit 17a performs detection with a phase synchronized with the applied voltage of the power amplifier circuit 14, extracts a current component having the same wavelength and the same phase as the applied voltage of the power amplifier circuit 14, and extracts the current from the first current value. Removes natural current and harmonic noise.
[0044]
Next, the second current detection circuit 16 calculates the current value (second current value; J) of the circuit (2). _1A ) And is output to the computer 19 via the phase detection circuit 17b and the A / D converter 18. Then, the computer 19 calculates the second current value J _1A Is stored in the RAM together with “i = 1” (step 104). Similarly to the phase detection circuit 17a, the phase detection circuit 17b performs detection with a phase synchronized with the applied voltage of the power amplifier circuit 14, and extracts a current component having the same wavelength and the same phase as the applied voltage of the power amplifier circuit 14. Then, natural current and harmonic noise are removed from the second current value.
[0045]
Next, the computer 19 has a 64th selection switching procedure (i = 64; upper linear electrode 11). ₈ And lower linear electrode 12 _H (Step 105). If i = 64 (step 105: YES), the processing after step 107 is performed. On the other hand, if i = 64 is not satisfied (step 105: NO), the process of step 106 is performed.
[0046]
In step 106, the computer 19 increments the i-th by 1 (i = i + 1), and repeats the processing after step 102. That is, the computer 19 stores the first current value and the second current value detected by the processing from “i = 1” to “i = 64”, respectively.
[0047]
In step 107, the computer 19 corrects the current flowing through the protective layer 3 based on the first current value and the second current value stored in the RAM (correction means). Next, this correction process will be described. For convenience of explanation, the first current value is expressed as Ixy, the second current value is expressed as Jxy, the maximum value of all the measured values of the first current value is Imax, and all the measured values of the second current value are Is expressed as Jmax. Also, the subscript “x” of I and J is “ ₁ "~" ₈ ”And the subscript“ y ” _A "~" _H Is shown.
[0048]
[Description of correction processing]
The first current value Ixy includes a current flowing through the water leak (circuit (3)) and a current flowing through the protective layer 3 (circuit (4)). For example, when the measurement result of the first current value Ixy measured in step 103 of the water leakage occurrence position detection process is displayed in a three-dimensional view from the first to the 64th, the measurement result shown in FIG. 4 is obtained. The x axis shown in FIG. 4 is the lower linear electrode 12. _A ~ 12 _H Where the y-axis is the upper linear electrode 11 ₁ ~ 11 ₈ The z-axis indicates the current value. The measurement result of the first current value Ixy from FIG. 4 indicates that the current value flowing through the water leak and the current value flowing through the protective layer 3 are included. Further, since the annular correction electrode 13 is provided in this embodiment, the upper and lower electric fields of the water shielding film 2 are controlled to have the same potential, and therefore, compared with the conventional three-dimensional view shown in FIG. In the three-dimensional view shown in FIG. 4, it can be seen that the current flowing through the protective layer 3 is reduced. However, this alone cannot eliminate the influence of the current flowing through the protective layer 3.
[0049]
On the other hand, the second current value Jxy is a current (circuit (4)) flowing through the protective layer 3. For example, when the measurement result of the second current value Jxy measured in step 104 of the water leakage occurrence position detection process is displayed as a three-dimensional diagram with the second current value alone from the first to the 64th, the measurement result shown in FIG. 5 is obtained. . The x-axis, y-axis, and z-axis shown in FIG. 5 are the same as those in FIG. From FIG. 5, the measurement result of the second current value Jxy is very similar to the tendency of the measurement result of the first current value Ixy measured by the current detection circuit 15 (see FIG. 4). It shows that the current that flows through is large. The second current value Jxy is measured through the correction electrode 13 (circuit (2)), but the correction electrode 13 is connected to the protective layer 3 and the ground around the water shielding film structure 1. It is considered that the tendency of the second current value Jxy is almost the same as the tendency of the current flowing through the protective layer 3 because it is arranged near the contacted portion.
[0050]
Therefore, the computer 19 obtains the first current value Ixy and the second current value Jxy stored in the RAM and the maximum values Imax and Jmax measured 64 times, respectively, as shown in Equation 1, and obtains the first current value. Then, the corrected current value Kxy is obtained by normalizing the second current value and subtracting them.
Kxy = Ixy / Imax−Jxy / Jmax Equation 1
[0051]
Then, the computer 19 obtains the corrected measurement value Kxy for each intersection position “i” from “i = 1” to “i = 64”, and stores it in the RAM. By the way, Equation 1 is displayed as a dimensionless number, but if Equation 2 shown below is used, a correction result Lxy having an order of current can be obtained.
Lxy = Imax * [Ixy / Imax−Jxy / Jmax]
[0052]
Next, the computer 19 outputs a command to display the corrected measurement value Kxy (or correction result Lxy) on the CRT screen to the CRT device (step 108). Then, the CRT device displays measured values Kxy from “i = 1” to “i = 64” at the intersection position of the CRT screen.
[0053]
Therefore, when the current measurement result of the annular correction electrode 13 is used to correct the first current value Ixy and display based on the corrected measurement value Kxy, a three-dimensional view shown in FIG. 6 is obtained. The x-axis, y-axis, and z-axis shown in FIG. 6 are the same as those in FIG. As described above, it can be seen that the correction process in step 107 can completely remove the influence of the current flowing through the protective layer 3 and provide a three-dimensional view in which the water leakage location is clear.
[0054]
That is, the upper and lower linear electrodes (11 _Three And 11 _C , 11 ₇ And 11 _C , 11 ₇ And 11 _H ), When water leakage occurs at intersections L1, L2, and L3 (see FIG. 2), if the corrected first current value is displayed, as shown in the three-dimensional view of FIG. The electrode combination intersections near the locations L1, L2, and L3 show a large value, and the first current value tends to decrease as the electrode combination intersections move away from the damaged portions L1, L2, and L3 of the water shielding film 2. Therefore, it becomes possible to know the leak occurrence positions L1, L2, and L3.
[0055]
Then, when the measured value Kxy is displayed on the CRT screen, the computer 19 ends the water leak occurrence position detection process.
[0056]
As in the above-described current value correction example, according to this embodiment, the characteristics of the current flowing through the protective layer 3 are grasped using the annular correction electrode 13, thereby flowing through the water leak. A correction was made to extract only the current (circuit (3)), and the leak occurrence position was detected. Therefore, when the water shielding film 2 breaks and water leakage occurs at the positions L1, L2, and L3, only the current flowing through the water leakage can be extracted, so the combination of linear electrodes close to the water leakage occurrence positions L1, L2, and L3 (11 _Three And 11 _C , 11 ₇ And 11 _C , 11 ₇ And 11 _H ) Is clearly detected to be higher than the current value between the other electrodes, and the detection accuracy of the water leakage occurrence positions L1, L2, and L3 is improved.
[0057]
In this embodiment, the measurement target for detecting the water leakage occurrence position has been described as a current value. However, the measurement target of the present invention may be an electrical resistance value obtained from the measurement current value and the applied voltage in addition to the current value. Good.
[0058]
In this embodiment, the power source is described as a two-phase AC power source that amplifies the signal waveform of the oscillation circuit 81 by the power amplifier circuit 14, but the power source may be an alternating DC power source. Further, although one end of the power source has been described in the case of being installed on the ground side of the water shielding film in FIG. 2, an electrode in a disposal site may be used in principle.
[0059]
【The invention's effect】
According to the present invention, the second current value flowing through the correction electrode measured by the second current detection circuit and the first current value measured by the first current detection circuit are expressed by the maximum value of the respective measurement values. By normalizing and taking each difference, the influence of the current flowing through the protective layer can be removed.
[0060]
In addition, according to the present invention, the correction electrode is used so that the potential of the water shielding film is basically the same, so that the current flowing through the water leak is affected by the current flowing through other water leaks and the protective layer. It can be clearly understood without.
[0061]
Furthermore, according to the present invention, the influence of the current flowing through the protective layer by the correction electrode can be reduced even under the condition that the protective layer using the soil material is provided on the entire surface of the water shielding film.
[0062]
Therefore, according to the present invention, by detecting the characteristics of the current flowing through the protective layer, the correction for extracting only the current flowing in the leakage is performed, and the leakage occurrence position detection having a correction function for improving the accuracy of detecting the leakage occurrence position. An apparatus and method thereof can be provided.
[Brief description of the drawings]
FIG. 1 is a side sectional view of a water shielding film structure, showing a state in which a current flows through a protective layer.
FIG. 2 is a block circuit diagram of a water leakage occurrence position detection device of the present invention.
FIG. 3 is a flowchart of a water leak occurrence position detection process of the present invention.
FIG. 4 is a three-dimensional view showing a measurement result of a first current value.
FIG. 5 is a three-dimensional view showing a measurement result of a second current value.
FIG. 6 is a three-dimensional view when the measurement result of FIG. 4 is corrected using a correction electrode.
FIG. 7 is a block circuit diagram of a conventional water leak occurrence position detecting device.
FIG. 8 is a three-dimensional view of a measurement result when the correction electrode is not operated.
[Explanation of symbols]
1 ... Water shielding film structure
1a ... hollow
2 ... Water shielding film
3 ... Protective layer
11 ₁ ~ 11 ₈ ... Upper linear electrode
12 _A ~ 12 _H ... Lower linear electrode
13 ... Annular correction electrode
14 ... Power amplification circuit (two-phase AC power supply)
15: First current detection circuit
16 ... Second current detection circuit
17a, 17b ... Phase detection circuit
18 ... A / D converter
19: Computer (correction means)
81. Oscillator circuit
84, 85 ... Electrode switcher (selective connection means)

Claims

A water-shielding film structure in which a water-shielding film of an electrical insulator is laid in a depression formed in the ground and a protective layer that conducts electricity is provided on the water-shielding film in a layered manner, and
A plurality of upper linear electrodes arranged in parallel and at predetermined intervals on the upper side of the water shielding film;
A plurality of lower linear electrodes arranged parallel to the lower side of the water shielding film across the water shielding film and arranged at a predetermined interval across the upper linear electrode;
The upper linear electrodes to select a set of the lower side wire-shaped electrode, and connecting the selected set of one linear electrode to the application terminal of the two-phase AC power source, a set of other selected Selective connection means for connecting the linear electrode to the other terminal that is not the application side of the two-phase AC power supply ;
An annular correction electrode connected to the other terminal that is not on the application side of the two-phase AC power source, the protective layer being disposed in the vicinity of the portion in contact with the ground;
A first current detection circuit for detecting a first current value flowing between a pair of linear electrodes the selected,
A second current detection circuit for detecting a second current value flowing between the linear electrode connected to the application side terminal of the two-phase AC power supply and the annular correction electrode;
The first connection value detected by the first current detection circuit and the second current detection circuit are detected by the selective connection means by sequentially switching the pair of the upper and lower linear electrodes. and correction means for using each of the second current value, the current component flowing through the protective layer from the first current value is respectively acquired corrected each correction current value respectively to be,
With
Detecting the water leakage position of the water shielding film structure from the relationship between the comparison result of each correction current value obtained by the correction means and the intersection position of the upper linear electrode and the lower linear electrode. A water leakage occurrence position detection device having a correction function as a feature.

The selective connection means selects one of the linear electrodes provided on either of the upper and lower sides of the water-shielding film and connects it to the application-side terminal of the two-phase AC power supply, and also connects the connection-side terminal to the application-side terminal. The linear electrode provided above and below the water shielding film other than the electrode and the annular correction electrode are connected to the other terminal that is not the application side, and the linear shape is connected to the application side terminal across the water shielding film 2. A leak detection position detecting device having a correction function according to claim 1, wherein the device has a selection connection function of selecting one linear electrode installed on the opposite side of the electrode and making the selected one set of linear electrodes. .

3. The correction function according to claim 1, wherein the first current detection circuit and / or the second current detection circuit includes a phase detection circuit that extracts a current component having the same wavelength and the same phase as the voltage applied to the power source. Water leakage occurrence position detection device.

Install a water-insulating film of electrical insulation in the depression formed in the ground,
A protective layer for conducting electricity is provided on the entire surface of the water barrier film in a layered manner to construct a water barrier film structure,
A plurality of linear electrodes are arranged above and below the water shielding film,
An annular correction electrode is disposed in the vicinity of the portion where the protective layer contacts the ground,
Said selecting a set of water-impervious film and below the linear electrode connected to the selected set of one linear electrodes of the application-side terminals of the two-phase AC power source, a set of other line selected Connect the electrode to the other terminal that is not the application side of the two-phase AC power supply ,
Connecting the annular correction electrode to the other terminal not on the application side of the two-phase AC power supply;
Detecting a first current value flowing between a pair of linear electrodes the selected,
Detecting a second current value flowing between the linear electrode connected to the application side terminal of the two-phase AC power source and the annular correction electrode;
The first current value detected by sequentially switching the set of the upper linear electrode and the lower linear electrode, and the second current value, respectively, from the first current value, respectively, Each corrected current value obtained by correcting the current component flowing through the protective layer is obtained ,
The leakage position of the water shielding film structure is detected from the relationship between the comparison result of the acquired correction current values and the intersection position of the upper linear electrode and the lower linear electrode. A method for detecting a water leakage occurrence position having a correction function.