JPH0754296B2 - Simple method for diagnosing deterioration of asphalt waterproof layer - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a simple deterioration diagnosis method for an asphalt waterproof layer applied to an asphalt waterproof layer waterproofed on a rooftop of a building.

[0002]

2. Description of the Related Art Conventionally, an asphalt waterproof layer that has been constructed on the roof of a building is subject to physical deterioration such as heat deterioration due to direct sunlight, atmospheric action, weather effects such as wind and rain, expansion and contraction of the base, and alkaline components of concrete. Since it deteriorates over time due to chemical action, it is necessary to diagnose the degree of deterioration at an appropriate time and, if necessary, to carry out preventive maintenance, partial repair, and full repair. The results of the “Ministry of Construction Comprehensive Technology Development Project” have been reported as a conventional method for diagnosing deterioration of the asphalt waterproof layer. (April 30, 1987
Supervised by the Ministry of Construction Secretariat Technical Research Office published by Gihodo Publishing,
(Refer to National Land Development Technology Research Center, Building Durability Improvement Technology Promotion Committee, "Building Durability Improvement Technology Series, Building Finishing Part II, Building Waterproof Durability Improvement Technology"). According to this, the deterioration diagnosis guideline of the waterproof layer is performed up to the primary, secondary, and tertiary diagnosis according to the survey item / method, etc.The tertiary diagnosis is the appearance, unit mass, thickness, and tensile strength of the waterproof layer. Strength, base material composition, appearance, unit mass, thickness, tensile strength,
It consists of many diagnostic items such as asphalt penetration and softening point.

[0003]

According to the deterioration diagnosis method of the asphalt waterproof layer in the above-mentioned "Ministry of Construction Comprehensive Technology Development Project", up to the above-mentioned physical property test of the tertiary diagnosis is performed to judge whether partial repair or full repair is to be performed. Although it is said that such a detailed physical property test requires a lot of precise experimental equipment, a long test day, a great deal of labor, a considerable skill, and a great deal of cost, A relatively large amount of sample must be collected, and the degree of deterioration cannot be easily determined at the site. Especially, in the case of penetration measurement, it is necessary to return to the test room and perform measurement under severe conditions. In addition, the tensile test in the test items is not a standard for the deterioration of asphalt over time,
Also, as the report of the above-mentioned project shows, the softening point test results widely vary in the case of exposed waterproofing where the softening point is high, and in the case of hold down waterproofing, they vary more widely in the region where the softening point is low. It is said that the relationship is not necessarily seen to increase and harden after 10 years in both cases, and the softening point is difficult to grasp as a criterion for deterioration. At this point, the softening point is measured by measuring the asphalt waterproof layer. It is said that it is difficult to set a reference value for the degree of deterioration. From the above, in the report of the project, the criterion for judging the deterioration of the asphalt waterproof layer is shown as the "deterioration diagnostic standard by penetration" based on the whole survey of all the asphalt waterproof layers. This is shown in Table 1 below.

[0004]

[Table 1]

As described above, in this project, asphalt deterioration is diagnosed for all the asphalt waterproof layers, and it is determined that the waterproof layers are close to the service limit when the penetration of all the layers is less than 10. Because it is a thing
In making the diagnosis, it is necessary to collect samples over all layers of the asphalt waterproof layer, and it is necessary to perform a troublesome measurement of penetration for all of the layers, and repair to prevent water leakage from the sampled points. It is troublesome such as requiring.
The penetration test has long been used as a guideline for aging deterioration of asphalt, and the penetration measurement method is JIS
It is necessary to use the method specified in K2207. That is, the measuring method is as follows: the sample is melted and put in a specified container, and the sample is left to stand in a constant temperature water bath of 25 ° C ± 0.1 ° C for 1 to 1.5 hours, and the surface thereof has a specified shape of a metal needle. The tip of the needle is applied, a weight of 100 g is applied, the needle is penetrated into the sample for 5 seconds, and the depth at which the needle is inserted is read on a scale (in this case, 1 degree on the scale plate indicates a needle penetration depth of 0. It corresponds to 1 mm) method. In this way, the method of measuring penetration is always 25
Strict measurement conditions of ℃ ± 0.1 ℃ are required. Moreover, considerable skill is required to perform this measurement. Because, when measuring the penetration, adjust the tip of the needle so that it touches the surface of the sample in water correctly, or start the stopwatch before starting the measurement, and when the stopwatch points to any scale, This is because it is necessary to press the clasp to lower the needle, and after exactly 5 seconds, release the clasp to stop the needle from descending. As described above, the above-described conventional method for diagnosing deterioration of the asphalt waterproof layer has a wide variety of investigation items for the third diagnosis, and in order to determine the degree of deterioration of the asphalt, the asphalt waterproof layer to be diagnosed is used for diagnosis. Since it is a method in which a sample is taken deeply over all layers each time and the penetration is directly measured over all layers, it takes a considerable amount of time and labor to obtain the degree of deterioration of asphalt as described above. It requires skill, equipment, and cost, and it is desirable to solve such problems. Therefore, the present inventor has studied to eliminate the above-mentioned conventional inconveniences, and as a result of conducting a test study, the deterioration of the asphalt waterproof layer is a surface that is exposed to sunlight and is exposed to the atmosphere and rainwater and the surface thereof. Focusing on the fastest progress in the area close to, from this viewpoint, a small amount of sample was taken from the surface layer of the asphalt waterproof layer to be diagnosed, and even without directly measuring asphalt penetration, Needle penetration is obtained by a simple work that does not require, so that the deterioration degree of the asphalt waterproof layer can be quickly diagnosed, and the above-mentioned conventional problems are solved.
It is to provide a simple method for diagnosing deterioration of an asphalt waterproof layer that satisfies the demand.

[0006]

The present invention relates to a simple method for diagnosing deterioration of an asphalt waterproof layer, which achieves the above object,
While measuring the penetration degree of each asphalt sample having different deterioration degree, the penetration resistance value of the needle was measured by a force gauge at each predetermined different temperature for each sample, and the penetration degree of each sample was measured. And the vertical axis and the horizontal axis of the needle penetration resistance value at each measured temperature for each sample are the penetration axis and the other is the scatter diagram obtained from the needle penetration resistance value axis. Make a regression curve on the measured temperature on each graph or on a chart that combines these graphs, and actually use small pieces of asphalt as a sample from the surface of the asphalt waterproof layer to be diagnosed. Sampled at any temperature,
It is characterized in that the penetration resistance value of the needle of the sample is measured, and the penetration degree is obtained from the measured value based on the chart.

[0007]

As described above, the method for diagnosing deterioration of the asphalt waterproof layer of the present invention requires only a small amount of sample to be collected from the surface thereof, and repair of the sampled portion is almost unnecessary. Further, the deterioration diagnosis method does not need to directly measure the penetration degree, but the penetration resistance value of the needle of the sample is measured by a force gauge at an arbitrary temperature, and the corresponding needle is prepared from the chart prepared in advance. Since the penetration can be obtained, the deterioration diagnosis of the asphalt waterproof layer can be performed very easily.

[0008]

EXAMPLES Examples of the present invention will be described in detail below.

JIS K2207 (petroleum asphalt) is the asphalt for waterproof construction to be diagnosed by applying this method.
However, since most of the waterproofing area is performed with 3 types of asphalt for waterproofing work, it is possible to use it for the deterioration diagnosis of the asphalt waterproof layer waterproofed by the following. A suitable embodiment will be described in detail. The deterioration diagnosis method of the asphalt waterproof layer of the present invention,
As shown below, a chart is prepared in advance, which shows the relationship between the penetration values of asphalts having different degrees of deterioration and the penetration resistance values of the needles by the force gauge. An example of the creation will be described in detail below. First, many asphalt samples with different degrees of deterioration are prepared. As the sample, a sample obtained by artificially varying the degree of deterioration of three kinds of asphalt raw materials,
It may be a sample that is actually taken from the asphalt waterproof layer that has been waterproofed for different years, or a sample that is a combination of these samples. The deterioration process is, for example,
Prepare a large number of sheets of 3 types of asphalt for waterproofing work with a softening point of 100 ° C or higher and a penetration of 20 to 40, and place these in air circulation type thermostats at a temperature of 80 ° C for different predetermined times. Let stand to obtain samples with different degrees of deterioration. This deterioration processing time is, for example, one month, two months, ... 6
The samples are set at appropriate intervals such as months or 1000 hours, 2000 hours, etc., and samples having different degrees of deterioration are manufactured. The larger the number of samples, the more detailed data can be obtained, but in practice, about 10 is sufficient.

Next, with respect to the thus prepared samples having different degrees of deterioration, the respective penetrations are measured by the penetration testing method defined in JIS K2207.

On the other hand, with respect to these samples having different degrees of deterioration,
The penetration resistance value of the needle is obtained as follows. That is, for each of these samples with different degrees of deterioration, an inner diameter of about 55 m
m and a depth of about 10 mm made of metal or heat-resistant glass container, and according to JIS K 2207, from the softening point of the sample 9
A test piece having a thickness of about 8 mm is prepared at a temperature as low as possible, for example, 190 ° C. so that the temperature is not higher than 0 ° C., and is heated and melted with occasional stirring to prevent partial overheating. Each of the test specimens thus prepared was placed in a temperature-controlled room, kept at a certain temperature, for example, at 10 ° C. for 8 hours or longer, and then regulated at the tip of a force gauge incorporating a microprocessor in the temperature-controlled room. With a measuring instrument equipped with a needle, the compressive force (Kg
f) is calculated. The average value of the compressive force measured three times is divided by the penetration depth of the needle, and the value converted to 1 mm is taken as the penetration resistance value (Kgf) of the needle. The measurement of the above-mentioned compressive force is carried out by any method, either by holding the measuring instrument by hand and inserting the needle into the test body, or by using an electric test stand to insert the needle at a constant speed. Good, but the same test specimen is measured three times. The measurement point is 10 mm or more from the peripheral wall of the sample container,
In addition, after the second time, a point separated by 10 mm or more from each penetration position of the previous measurement is selected. The present inventors conducted various preliminary experiments for measuring the compressive force and found that the thickness of the test piece was 8 m.
If it is m or more, there is little variation in the measured value, and it increases in proportion to the penetration depth of the needle, but there is almost no difference if the average value of the measurement data is divided by the penetration depth of the needle and converted to 1 mm, Furthermore, it was confirmed that there was almost no difference between operating the measuring instrument by hand and using the electric test stand.

In this way, the penetration resistance values of the respective needles measured at a certain temperature determined in the temperature-controlled room, that is, 10 ° C. in the above-mentioned case, are also obtained for the samples having different degrees of deterioration. In addition, for example, the penetration resistance value of each needle is taken on the vertical axis, and the horizontal axis is taken on the basis of the penetration values of the samples with different deterioration degrees obtained by the penetration test method specified in JISK 2207. The penetration degree of each needle is taken, a scatter diagram is created from the penetration resistance value and the penetration degree of the corresponding needles, and a regression curve at a measurement temperature of 10 ° C. is obtained by a statistical method from the scatter diagram. Similarly, the penetration resistance values of the needles of the samples having different degrees of deterioration are measured while changing the temperature. That is, the temperature of the temperature-controlled room is set to a suitable temperature interval such as 5 ° C., 15 ° C., 20 ° C., 25 ° C., 30 ° C., 35 ° C. other than 10 ° C., and these predetermined constant temperatures are set. After holding and leaving it for 8 hours, the same measurement is performed, the needle penetration resistance value of each sample at each temperature is measured, and the needle penetration resistance value and the previous penetration degree at each temperature are similarly measured. Based on and, scatter plots corresponding to these are created, and a regression curve at each measured temperature is obtained by a statistical method. In this case, the lower limit and the upper limit of the measured temperature range are appropriately determined as needed.
5 ° C, 15 ° C, 20 ° C, 25 ° C, 30 thus obtained
As shown above, seven types of regression curves of ℃ and 35 ℃ are drawn on the respective graphs with the vertical axis as the needle penetration resistance value axis and the horizontal axis as the penetration axis, for each measured temperature. Or a graph in which all of these regression curves are put together on one common graph is created.

By using the chart created in this way, JIS
The deterioration diagnosis of the aged waterproof layer which has been waterproofed on a rooftop or the like using the asphalt for waterproofing specified by K 2207 (petroleum asphalt) is performed as follows. That is, a small piece of asphalt is taken from the surface layer of the asphalt waterproof layer to be diagnosed which is actually waterproofed, and this sample is subjected to the same procedure as above at the site or in a desired temperature-controlled room, that is, according to JIS K2207. A test body is prepared by using the force gauge, the compression force is measured three times using a force gauge in the same manner as described above, and the penetration resistance value of the needle is determined from the average value. The temperature at the time of this measurement is 1 of the regression curve drawn on the above chart.
If the temperature is the same, the value on the axis of penetration scale corresponding to the point at which the penetration resistance value of the needle intersects the regression curve is determined as the penetration degree of the sample asphalt. If the temperature at the time of measurement does not match any of the temperatures of the regression curves of the respective measured temperatures on the chart, the regression at the measured temperature between the two regression curves above and below the measured temperature closest to the measured temperature. A point at which the penetration resistance value of the needle on the curve intersects with the regression curve is assumed, and the penetration degree corresponding to the point can be obtained on the penetration degree scale axis.

The penetration resistance value of the needle of the sample may be measured at the ambient temperature of the site, or may be set and maintained at a desired constant temperature in a temperature-controlled room. If the measured temperature matches the temperature of one of the regression curves of the respective measured temperatures created in advance, for example, the penetration degree corresponding to this is determined based on the regression curve of the corresponding measured temperature. Good. In this case, it is needless to say that a chart having a regression curve matching the corresponding measured temperature selected from the charts prepared for the respective measured temperature curves prepared in advance as described above may be used.

Since the degree of deterioration of the asphalt waterproof layer can be known from the penetration value thus obtained, based on this,
It is possible to determine whether or not the preventive maintenance of the waterproof layer, the partial repair or the whole surface repair, the whole surface repair and the like are required. Table 2 below
Shows a judgment standard table that classifies the penetration level (that is, the classification of the deterioration degree) and the necessity or the degree of the treatment of the asphalt waterproof layer diagnosed according to the penetration level. The method of classifying is not limited.

[0016]

[Table 2]

Next, a more specific embodiment will be described. J
Softening point 100 ° C that conforms to 3 types of waterproofing asphalt specified in IS K 2207 (petroleum asphalt)
As described above, a large number of asphalts having a penetration of 30 were formed into a sheet having a thickness of about 1.2 mm and a size of about 300 mm by a hand-rolling machine, and 9 sheets of these sheets were heated at a temperature of 8
It is left standing in an air circulation type constant temperature bath at 0 ° C., and its deterioration treatment time (that is, accelerated deterioration time) is changed as shown in Table 3 below to perform deterioration treatment, and nine kinds of accelerated deterioration samples with different deterioration degrees are prepared. did. On the other hand, a total of 12 types of samples with different degrees of deterioration were prepared, including old asphalt deterioration samples that were waterproofed on the rooftops of buildings in different locations, and the penetration degree specified in JIS K2207 was prepared for each of them. Penetration was measured by the test method. Table 3 below shows the relationship between the degree of deterioration of each sample and the degree of penetration.

[0018]

[Table 3]

On the other hand, each of the above 12 kinds of samples was put into a petri dish having an inner diameter of about 55 mm and a depth of about 10 mm, and the sample was heated and melted at a relatively low temperature, for example, at 190 ° C. with stirring to obtain a thick film. Each test piece of about 8 mm is made,
These test bodies were placed in a temperature-controlled room, and the room temperature was 10 ° C.
After being left still at the temperature of 8 hours for 8 hours, a microprocessor force gauge MFG 50 manufactured by Shinko Denshi KK as a measuring instrument and JIS S 3008 as a penetrating needle are used.
Use the specified hand sewing needle No. 19 (measured diameter 1.04 mm),
The penetration depth of the needle was set to 3 mm, the measuring instrument was held by hand, the penetration force of the needle when the needle was penetrated and the depth of 3 mm was penetrated, that is, the maximum compression force was measured. Penetration of the needle was performed three times in the same test piece at different locations, and the compression force of each was measured. The measuring point of the compressive force was selected 10 mm or more from the peripheral wall of the petri dish, and 10 mm or more from each penetration position of the previous measurement after the second measurement. The average value of the three measurements was divided by the needle penetration depth of 3 mm and converted per 1 mm to obtain the needle penetration resistance value. In this way, the vertical axis represents the needle penetration resistance value based on the needle penetration resistance value of each of the 12 types of samples at the measurement temperature of 10 ° C., and the horizontal axis represents each penetration value. A scatter diagram of the penetration value of each needle and the penetration resistance value of each needle was created, and from this, a regression curve at 10 ° C. was obtained. Further, for each of these 12 types of test bodies, the needle penetration of each test body at each temperature was performed in the same manner as above except that the temperature of the temperature-controlled room was changed to 15 ° C, 20 ° C, 25 ° C, and 30 ° C, respectively. Resistance values were obtained, scatter plots were similarly prepared at each temperature, and regression curves were obtained from this.

Thus, as shown in FIG. 1, the five types of regression curves with different measured temperatures thus obtained have the vertical axis as the scale of the needle penetration resistance value and the horizontal axis as the penetration degree. A chart used for the simple method of diagnosing deterioration of the asphalt waterproof layer of the present invention was prepared by placing it on a common graph composed of a scale axis of values. In Table 1, a, b, c, d, and e show regression curves at measurement temperatures of 30 ° C, 25 ° C, 20 ° C, 15 ° C, and 10 ° C, respectively.

As the asphalt waterproof layer to be diagnosed, an exposed asphalt waterproof layer 14 years after waterproofing on the rooftop of a building in Konosu City, Saitama Prefecture was selected, and about 30 g was sampled from the surface, and a test sample was prepared in the same manner as above. Was prepared, and the penetration resistance value of the needle was determined by the same method. The measurement temperature was 22 ° C., and the needle penetration resistance value was 0.5 Kgf. Therefore, using the above-mentioned chart of the present invention, a regression curve corresponding to the measured temperature of 22 ° C. is placed on the line of the needle penetration resistance value of 0.5 between the regression curve c at 20 ° C. and the regression curve b at 25 ° C. Assuming the position of, the penetrating degree 11 can be obtained from the point where the downward line shown by the dotted line intersects with the penetrating degree scale axis. This penetration was judged to be the degree of deterioration of the asphalt waterproof layer, and it was diagnosed that preventive maintenance of the surface layer was necessary.

[0022]

As described above, according to the present invention, as described above, the penetration of asphalt samples having different degrees of deterioration is measured in advance, and these penetrations and the predetermined different temperatures of the respective samples are measured. In order to prepare a chart that shows the regression curve showing the relationship with the penetration resistance value of each needle by the force gauge in the above, after that, the deterioration degree of the asphalt waterproof layer for which the deterioration degree should be diagnosed When diagnosing
There is no need to directly measure the penetration degree each time, a small amount of sample is taken from the surface, and the penetration resistance value of the needle of the test body is obtained by a force gauge at an arbitrary temperature, and the value is Regression curves at the respective measured temperatures of the needle penetration and needle penetration resistance values that were created in advance on the graph separately,
Alternatively, based on the diagram collectively shown, simply by determining the penetration degree for this, easily brings about the effect of diagnosing the degree of deterioration of the asphalt waterproof layer, each time a deterioration diagnosis of the asphalt waterproof layer as in the past, Measuring the penetration from each sample directly according to JIS K 2207,
In other words, the degree of deterioration of the waterproof layer, which must be measured at a temperature of 25 ° C. ± 0.1 ° C., eliminates the inconvenience and troublesomeness of the measurement work that requires skill, and is extremely simple and quick to diagnose. Moreover, compared to testing all the items shown in the conventional tertiary diagnosis, the amount of sample taken is small, and the labor, time, and equipment cost required for the diagnosis are also required. And the like, the measuring instrument is extremely inexpensive, can be easily operated without requiring skill, and is highly efficient and economical.

[Brief description of drawings]

FIG. 1 is an example of a diagram of the present invention used for a simple method of diagnosing deterioration of an asphalt waterproof layer of the present invention.

[Explanation of symbols]

a, b, c, d, e 30 ° C, 25 ° C, 20 ° C, 15
Regression curve at 10 ℃

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hidehiro Horitake 1-6 Uchisaiwaicho, Chiyoda-ku, Tokyo Nihon Telegraph and Telephone Corporation (72) Inventor Katsuaki Sekihara 2-23 Senjuhigashi, Adachi-ku, Tokyo No. 4 within Nissin Kogyo Co., Ltd. (72) Inventor Junkichi Asai 2-23-4 Senjuhigashi, Adachi-ku, Tokyo Within Nisshin Kogyo Co., Ltd.

Claims (1)

[Claims] 1. The penetration of each of the asphalt samples having different degrees of deterioration is measured, and the penetration resistance value of the needle is measured by a force gauge at each of predetermined different temperatures. Scatter diagram with one of the vertical axis and the horizontal axis of the penetration resistance value of the needle at each measured temperature for each sample and the penetration axis of the needle and the other axis of the penetration resistance value of the needle The regression curve at each measured temperature obtained from the above is created on each graph or in a chart composed of these graphs, and the asphalt waterproof layer surface to be diagnosed Is taken as a sample, the penetration resistance value of the needle of the sample is measured at an arbitrary temperature, and the penetration is determined from the measured value based on the chart above. A simple method for diagnosing deterioration of waterproof layer.