JP3710218B2 - Construction method of impermeable revetment at seaside plant - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a water-impervious revetment for shielding and partitioning a dumped sea area in order to dump a managed industrial waste produced by a coastal plant into the sea.
[0002]
[Prior art]
When final disposal of powdered controlled industrial waste, such as coal ash, sewage sludge incineration ash, or slag, generated at a seaside plant such as a power plant, sewage treatment facility, or smelter, is the industrial waste In order to prevent toxic substances from leaching into the surrounding seawater, it is necessary to partition the final disposal site, that is, the sea area to be dumped, by impermeable revetment. As such a water-impervious structure that forms a water-impervious revetment, the structure shown in FIG.
[0003]
In FIG. 5, the water-impervious structure 100 includes a steel sheet pile 101 functioning as a water-impervious plate and a breakwater 102 in which a plurality of concrete blocks 102a are piled up.
The steel sheet pile 101 is driven up to an opaque layer on the seabed, and can thereby shield the seawater in the final disposal site from the surrounding sea area.
The breakwater 102 is installed at least on the open ocean side of the steel sheet pile 101 to buffer the impact of waves from the open ocean on the steel sheet pile 101.
The impermeable revetment is completed by continuously extending the impermeable structure having such a structure so as to surround the final disposal site. The managed industrial waste generated from the coastal plant is dumped into the impermeable revetment for final disposal.
[0004]
[Problems to be solved by the invention]
As mentioned above, in order to prevent the toxic substances of managed industrial waste dumped in the sea from leaching into the seawater, the impermeable revetment needs to be established before the operation of the plant where the waste is generated. For example, in the case of a thermal power plant, it is necessary to construct a water-impounded revetment at the final disposal site that allows dumping of management-type industrial waste for about 10 years according to the agreement of the Power Development Coordination Council.
Therefore, there was a problem that a large amount of revetment construction costs were needed at one time before profits from the plant operation could not be obtained, and if the loan from financial institutions etc. was received to compensate for this, the burden of interest would be large. . In addition, the size of the final disposal site must be determined in anticipation of the amount of managed industrial waste generated from the plant. However, sometimes it was too wide and the revetment was wasted.
[0005]
Therefore, the object of the present invention is to minimize the cost required for the construction of the impermeable revetment before the operation of the coastal plant, and according to the amount of managed industrial waste generated from the coastal plant. The purpose is to provide a method for constructing a water-impounded revetment for a coastal plant that can form a final disposal site of an optimal size.
[0006]
[Means for Solving the Problems]
According to the present invention, a water-impervious structure comprising a water-impervious plate standing upright from the sea floor and at least a revetment block stacked facing the open ocean side of the water-impervious plate is disposed around the coastal plant. In the construction method of a seawater revetment of a coastal plant formed by extending over a predetermined sea area, (i) a step of generating a revetment block containing managed industrial waste generated by the operation of the coastal plant; ii) a step of stacking the revetment block at a construction location of the water-blocking revetment, (iii) a step of standing the water-shielding plate inside a location where the revetment block is stacked, and (iv) the step There is provided a method for constructing a seawater revetment in a coastal plant, comprising the steps of: (i) to (iii) being repeated to continuously construct a watertight structure and forming a water revetment.
[0007]
According to the construction method of the present invention, when constructing the impermeable revetment, it is not necessary to dump the waste into the sea in order to use the managed industrial waste generated from the coastal plant in the revetment block that forms the revetment, In parallel with the operation of the seaside plant, it is possible to construct a water-impervious revetment and to effectively use the waste.
Therefore, it is not necessary to establish a water-impervious revetment before the coastal plant is in operation, and the profits obtained from the operation of the coastal plant can be used as construction costs for the water-impervious revetment, requiring a large amount of water-impervious revetment construction cost before the operation. And not. In addition, it is possible to change the construction of the final disposal site according to the operating status.
[0008]
In the present invention, as a method of generating the revetment block, since it is necessary to prevent the toxic substances of managed industrial waste from being eluted into the sea, for example, the method described in Japanese Patent Application No. 7-160906 is adopted. It is preferable to do.
As the management-type industrial waste mixed in the revetment block, the above-described coal ash, sewage sludge incineration ash, or slag, etc. can be applied. Moreover, it is preferable that the said bank protection block has the unevenness | corrugation fitted mutually from the point of the convenience of the said loading, and the strength improvement. In particular, in a sea area with severe wave conditions, it is preferable to use ordinary concrete, heavy concrete, or natural stone as a block to directly receive the outermost waves. In the step (ii), the standing of the water shielding plate may not necessarily be after the stacking of the revetment block is completed, and may be performed in parallel with the stacking. A steel sheet pile, a steel pipe sheet pile, or the like can be used as the water shielding plate.
Moreover, according to this invention, the said revetment block may be piled up on both sides of the spacer temporarily installed previously, the said spacer may be removed after that, and a water shielding board may be stood | installed there. If such a construction method is employed, the work process can be simplified. A steel frame or the like can be used as the spacer.
[0009]
Furthermore, according to the present invention, the revetment block can be stacked and positioned by GPS (Global Positioning System). GPS is a surveying technology that uses an artificial satellite. A receiver is installed at a fixed point on land, and the distance from the receiver to the measuring object is measured by measuring the measuring object from the artificial satellite and the distance of the receiver. Is to measure.
[0010]
In the present invention, an antenna is installed in a device for positioning the revetment block, and the distance between the antenna and the receiver is measured by using the GPS. Positioning can be performed.
[0011]
According to such a method, it is possible to perform accurate loading as compared with a conventional diving operation, and to prevent personal injury and the like.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described with reference to the accompanying drawings.
FIG. 1 is a schematic diagram of a coastal plant showing a thermal power plant 1, a water-impervious revetment 2, and a final disposal site 2a divided into the revetment 2a. FIG. 2 is a cross-sectional view taken along line AA in FIG. 1 showing the water-impervious structure 3 that forms the impermeable revetment 2. The water-impervious structure 3 includes a block dam 4 in which a plurality of blocks 4a are stacked, and a steel It consists of a sheet pile 5.
The block 4a is kneaded with coal ash generated by the operation of the thermal power plant 1, cement, and seawater, and then placed in a mold having a predetermined shape, so that the electrical resistance value of the kneaded material such as coal ash decreases. (The details are described in Japanese Patent Application No. 7-160906). According to this manufacturing method, the toxic substances contained in the coal ash are not eluted from the block 4a into the sea after curing.
[0013]
Next, FIG. 3 is an external view of the block 4a. Both surfaces of the block 2a are provided with convex portions at the four corners and a cross-shaped concave portion at the center. The width of the concave portion is about twice the width of the convex portion, and when the blocks 2a are stacked, the plurality of blocks 4a can be alternately fitted and stacked. Thus, the block bank 4 can be structurally stabilized by stacking the blocks 4a by fitting alternately. When sea conditions are severe, it is preferable to stabilize the revetment structure by separately laying a heavy concrete block (not shown) on the surface of the block bank 4.
[0014]
The construction procedure of the water-impervious structure 3 having such a configuration will be described with reference to FIG. 4 which is a side view of the block lantern 4 in the middle of construction.
The power plant 1 is operated, and the block 4a is generated by the method described above using the generated coal ash. That is, during construction of the impermeable revetment 2, the coal ash does not need to be dumped into the sea and can be used for the block 4a.
Next, the spacer 8 is temporarily installed in the sea, and the work of carrying and stacking the blocks 4a on both sides by the crane 6 is performed. In order to make the positioning accurate and easy, GPS (Global Positioning System) is adopted. The GPS is composed of an artificial satellite 5, an antenna 6a installed on a boom of a crane 6 having an automatic control device, and a receiver 7 installed at a fixed point in the vicinity. In such GPS, the positions of the antenna 6 a and the receiver 7 can be measured from the artificial satellite 5. From each position, the distance between the antenna 6a and the receiver 7 is determined, and based on this distance, the automatic control device of the crane 6 corrects the loading position of the block 4a, and performs accurate loading.
[0015]
The crane 6 sequentially moves on the block slab 4 for which construction has been completed, and extends the block dam 4. Then, at the location where the block 4a has been stacked, the temporarily installed spacer 8 is extracted, and at the same time, the steel sheet pile 5 that functions as a water shielding plate is driven to the opaque layer on the seabed of the location, Part of revetment 2 is completed.
Hereinafter, this operation is repeated according to the amount of coal ash produced by the power plant 1 to complete the impermeable bank 2. After the impermeable revetment is completed, the coal ash can be dumped into the sea inside the impermeable revetment 2 for final disposal.
[0016]
【The invention's effect】
As described above, according to the present invention, when constructing the impermeable revetment, it is not necessary to dump the waste into the sea in order to use the managed industrial waste generated from the seaside plant in the revetment block that forms the revetment. Therefore, a water-impervious revetment can be constructed in parallel with the operation of the coastal plant, and the waste can be effectively used.
Therefore, there is no need to establish a water-impervious revetment before the coastal plant is in operation, and the profits gained from the operation of the coastal plant can be used as construction costs for the water-impervious revetment. And not. It is also possible to change the size of the final disposal site according to the operating status.
[Brief description of the drawings]
FIG. 1 is a schematic diagram of a coastal plant.
FIG. 2 is a cross-sectional view of a water shielding structure 3. FIG.
FIG. 3 is an external view of a block 2a.
FIG. 4 is a side view of the block bank 4 during construction.
5 is a cross-sectional view of a conventional water shielding structure 100. FIG.
[Explanation of symbols]
1. Thermal power plant 2. Impermeable revetment 3. Impermeable structure 4. Block dike 4a. block

Claims (3)

A water-impervious structure consisting of a water-impervious plate standing upright from the bottom of the sea and a revetment block stacked at least on the open-sea side of the water-impervious plate extends over a predetermined area around the coastal plant. In the construction method of the impermeable revetment of the seaside plant
(I) generating a revetment block containing managed industrial waste generated by the operation of the seaside plant;
(Ii) a step of stacking the revetment block at a construction site of the impermeable revetment;
(Iii) a step of erecting the water shielding plate inside the place where the revetment block is stacked;
(Iv) Construction method of impermeable revetment for coastal plant, comprising the steps of constructing a impermeable structure continuously by repeating the steps (i) to (iii) and forming the impermeable revetment . Steps (ii) and (iii)
(Ii) 'placement of spacers at the construction site of the impermeable revetment, and stacking the revetment blocks on both sides thereof;
(Iii) 'The method for constructing a seawater revetment in a seaside plant according to claim 1, comprising the step of removing the spacer and standing a water shielding plate there. 3. The method for constructing a seawater revetment in a seaside plant, wherein in step (ii) or (ii) 'in claim 1 or 2, the revetment block is stacked and positioned by GPS.

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