Quantitative evaluation method and evaluation system for water stop effect of water stop curtain

Abstract

The invention relates to the technical field of building construction, in particular to a quantitative evaluation method and evaluation system for the water stop effect of a water stop curtain. The quantitative evaluation method for the water-stopping effect of the water-stopping curtain comprises the steps that drilling exploration and sampling are conducted on a water-stopping curtain body to be detected, a rock sample is tested, drilling data including compressive strength, permeability, the sampling rate and the consolidation condition are evaluated, a test hole is tested, hydrological parameters are evaluated, and the water-stopping effect of the water-stopping curtain is evaluated. Comprising the permeable rate, the permeability coefficient and the water level drop condition, summarizing the evaluation result, comparing the evaluation result with a waterproof curtain standard evaluation table, and determining the quantitative evaluation effect of the waterproof curtain body to be detected according to the judgment result. According to the method, existing single-factor evaluation of the waterproof curtain in the loess area is converted into multi-factor comprehensive evaluation, so that qualitative evaluation is converted into semi-quantitative evaluation, the seepage-proofing and water-stopping effects of the vertical waterproof curtain body are guaranteed, and a dry construction environment is created for foundation pit excavation and foundation construction.

Description

Technical Field

[0001] The invention relates to the technical field of building construction, and in particular to a quantitative evaluation method and system for the water-stopping effect of a water-stopping curtain. Background Art

[0002] As one of the auxiliary dewatering measures in foundation pit dewatering in the Loess Plateau, the water-stopping curtain has a direct impact on the construction quality and safety. However, the evaluation of the effect of the water-stopping curtain has always been a difficult problem, and qualitative evaluation methods such as core drilling and permeability coefficient method are commonly used. However, due to the complexity of engineering conditions, the existing qualitative evaluation methods have certain errors or even misjudgments, which can easily bring certain hidden dangers to engineering construction. Summary of the invention

[0003] The technical problem to be solved by the embodiments of the present invention is to provide a quantitative evaluation method and evaluation system for the water-stopping effect of a water-stopping curtain, so as to solve the problem that the effect evaluation of the water-stopping curtain in the prior art is prone to errors and misjudgments.

[0004] The invention discloses a method for quantitatively evaluating the water-stopping effect of a water-stopping curtain, comprising: Selecting a water-stop curtain body to be tested, drilling and exploring the water-stop curtain body to be tested and taking samples to obtain a test hole and rock samples at a corresponding hole position; Conducting tests on the rock samples and evaluating the drilling data of the rock samples, the drilling data including compressive strength, permeability, recovery rate and consolidation condition; Conducting tests on the test hole and evaluating the hydrological parameters of the test hole, wherein the hydrological parameters include water permeability, permeability coefficient and water level drop; Summarize the assessed drilling data and hydrological parameters, and make a one-to-one correspondence between the summarized assessment results and the standard evaluation table for water-stop curtains for qualification determination; According to the borehole data and the judgment of the qualification of each factor in the hydrological parameters, the quantitative evaluation effect of the water-stop curtain body to be tested is determined.

[0005] Optionally, the method of drilling and sampling the water-stop curtain body to be inspected is: Dividing the water-stop curtain body to be tested into a plurality of test sections; According to the divided test sections, drilling exploration is performed on each of the test sections, and each of the test sections includes at least three test holes; In the process of drilling exploration of each test section, taking out representative rock samples from each test hole; Each of the rock samples taken out is marked, and the hole position and hole depth of each test hole are recorded.

[0006] Optionally, the method further includes testing the rock sample to determine the compressive strength: Using rock mechanics testing equipment to sequentially perform compressive strength tests on the marked plurality of rock samples; The maximum pressure of each rock sample when it is destroyed is recorded to obtain the compressive strength of the rock sample.

[0007] Optionally, the method further includes testing the rock sample to determine the permeability: Using a permeability testing device to sequentially perform permeability tests on the marked plurality of rock samples; Under a preset water head pressure, the amount of water passing through the rock sample within a predetermined time is measured, and the permeability of the rock sample is calculated.

[0008] Optionally, the method further includes testing the rock sample to determine the recovery rate: sequentially obtaining the actual sizes of the marked plurality of rock samples; The actual size of the rock sample is compared and calculated with the preset theoretical sampling size to obtain the sampling rate of the rock sample.

[0009] Optionally, the method further includes testing the rock sample to evaluate the consolidation condition: Using a consolidation test device to sequentially perform consolidation tests on the marked plurality of rock samples; Under a preset constant load, recording the pore water pressure and volume change data of the rock sample at different time points; The consolidation coefficient and degree of consolidation of the rock sample are calculated based on the recorded pore water pressure and volume change data; The consolidation condition of the soil layer corresponding to the rock sample is evaluated according to the consolidation coefficient and the consolidation degree.

[0010] Optionally, the method further includes testing the test hole to determine the water permeability: Using a pumping device to sequentially conduct a pumping test on the plurality of test holes; During the pumping test, the pumping flow rate at different time points and the corresponding water level changes in the test hole are recorded; The water permeability of the test hole is calculated according to the pumping flow rate, the water level drop height and the cross-sectional area of ​​the test hole.

[0011] Optionally, the method further includes testing the test hole to determine the permeability coefficient: Using a water pressure device to sequentially perform a water pressure test on the plurality of test holes; During the water pressure test, record the injection flow rate and injection time at different pressures; The permeability coefficient corresponding to the test hole is calculated according to the injection flow rate, the injection time, the cross-sectional area of ​​the test hole, and the hole depth.

[0012] Optionally, the method further includes testing the test hole to assess the water level drop: Installing water level monitoring equipment in each of the test holes in turn, and recording the daily water level changes in the test holes within a preset period; The water level drop corresponding to the test hole is evaluated according to the water level change of the test hole.

[0013] The present invention also discloses an evaluation system, which is applied to the above-mentioned quantitative evaluation method of the water-stopping effect of the water-stopping curtain, comprising: A sampling module, used for drilling and sampling the water-stop curtain body to be inspected; A rock sample test module, used to test the rock sample and evaluate the drilling data of the rock sample; A test hole experimental module, used to test the test hole and evaluate the hydrological parameters of the test hole; A determination module, for summarizing the assessed drilling data and the hydrological parameters, and making a one-to-one correspondence between the summarized assessment results and the standard evaluation table for water-stop curtains; The evaluation module is used to determine the quantitative evaluation effect of the water-stop curtain body to be tested based on the judgment of the qualification of each factor in the drilling data and the hydrological parameters.

[0014] Compared with the prior art, the quantitative evaluation method and evaluation system for the water-stopping effect of the water-stopping curtain provided by the embodiment of the present invention have the following beneficial effects: The effect of the high-pressure jet grouting pile water-stop curtain is evaluated by adopting a comprehensive scoring method combining the drilling method and the hydrological parameter method. That is, the quality of the water-stop curtain is evaluated by using the drilling data including the extraction rate, compressive strength, permeability coefficient K and consolidation conditions, and the hydrological parameters including the water permeability, permeability coefficient and water level drop conditions, and the water-stop curtain in the loess region is transformed from the existing single-factor evaluation to a multi-factor comprehensive evaluation, so as to realize the transformation from qualitative evaluation to semi-quantitative evaluation, ensure the anti-seepage and water-stopping effect of the vertical water-stop curtain body, and thus create a dry construction environment for foundation pit excavation and foundation construction. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments, in which: Figure 1 A schematic block diagram of the steps of a method for quantitatively evaluating the water-stopping effect of a water-stopping curtain provided in an embodiment of the present invention; Figure 2A schematic block diagram of the various stages of the execution of a method for quantitatively evaluating the water-stopping effect of a water-stop curtain provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0016] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. Now, in conjunction with the accompanying drawings, the preferred embodiments of the present invention are described in detail.

[0017] The present invention discloses a method for quantitatively evaluating the water-stopping effect of a water-stopping curtain. Figure 1 and Figure 2 As shown, including: S1. Select a water-stop curtain body to be tested, conduct drilling exploration and sampling on the water-stop curtain body to be tested, and obtain a test hole and rock samples at the corresponding hole position; S2. Test the rock samples and evaluate the drilling data of the rock samples, including compressive strength, permeability, recovery rate and consolidation conditions; S3. Test the test hole and evaluate the hydrological parameters of the test hole, which include water permeability, permeability coefficient and water level drop; S4. Summarize the assessed drilling data and hydrological parameters, and make a one-to-one correspondence between the summarized assessment results and the standard evaluation table for water-stop curtains for qualified determination; S5. Determine the quantitative evaluation effect of the water-stop curtain body to be tested based on the borehole data and the qualification of each factor in the hydrological parameters.

[0018] Through the implementation of the quantitative evaluation method of the water-stopping effect of the water-stopping curtain mentioned above, the comprehensive scoring method combining the drilling method and the hydrological parameter method is used to evaluate the effect of the high-pressure rotary jet pile water-stopping curtain. That is, the drilling data including the collection rate, compressive strength, permeability coefficient and consolidation conditions, and the hydrological parameters including the permeability, permeability coefficient and water level drop are used to evaluate the quality of the water-stopping curtain, and the water-stopping curtain in the loess area is transformed from the existing single-factor evaluation to a multi-factor comprehensive evaluation, so as to realize the transformation from qualitative evaluation to semi-quantitative evaluation, ensure the anti-seepage and water-stopping effect of the vertical water-stopping curtain body, and thus create a dry construction environment for foundation pit excavation and foundation construction.

[0019] Further, the method of drilling and sampling the water-stop curtain body to be tested is as follows: Divide the water-stop curtain body to be tested into multiple test sections; According to the divided test sections, drilling exploration is carried out for each test section respectively, and each test section includes at least three test holes; During the drilling exploration of each test section, representative rock samples are taken from each test hole; Mark each rock sample taken out and record the hole position and depth of each test hole.

[0020] Through the implementation of the quantitative evaluation method of the water-stopping effect of the water-stopping curtain, the water-stopping curtain body can be divided into several independent test sections according to factors such as geological conditions, design requirements, construction methods and expected waterproofing effects, so as to realize the segmented evaluation of the water-stopping curtain body. By conducting drilling exploration in each test section, detailed information of the underground soil layers corresponding to different test sections can be obtained. At least three test holes are set in each test section, multiple test points are provided for each test section, representative rock samples are taken from each test hole, and the evaluation results of the multiple test holes included in each test section are combined to obtain the water-stopping effect of different test sections of the water-stopping curtain body, so as to more accurately evaluate the overall performance of the water-stopping curtain body, ensure that it can effectively prevent the infiltration of groundwater, and meet the safety and waterproofing requirements of the engineering design.

[0021] Furthermore, it also includes a method for testing and evaluating the compressive strength of rock samples: The rock mechanics testing equipment is used to carry out compressive strength tests on the marked multiple rock samples in sequence; The maximum pressure of each rock sample at failure was recorded to obtain the compressive strength of the rock sample.

[0022] Furthermore, the method of testing and evaluating the permeability of rock samples is also included: The permeability test equipment is used to sequentially conduct permeability tests on the marked multiple rock samples; Under the preset head pressure, the amount of water passing through the rock sample within a predetermined time is measured, and the permeability of the rock sample is calculated.

[0023] Furthermore, it also includes a method for testing and evaluating the recovery rate of rock samples: sequentially obtaining the actual sizes of the marked multiple rock samples; The actual size of the rock sample is compared with the preset theoretical sampling size to obtain the rock sample collection rate.

[0024] Furthermore, it also includes a method for testing and evaluating the consolidation condition of rock samples: The consolidation test equipment is used to carry out consolidation tests on the marked multiple rock samples in sequence; Under the preset constant load, record the pore water pressure and volume change data of the rock sample at different time points; The consolidation coefficient and degree of consolidation of the rock sample are calculated based on the recorded pore water pressure and volume change data; The consolidation condition of the soil layer corresponding to the rock sample is evaluated based on the consolidation coefficient and consolidation degree.

[0025] Through the implementation of the above-mentioned quantitative evaluation method of the water-stopping effect of the water-stopping curtain, the value of the consolidation coefficient can reflect the consolidation rate of the soil layer. Generally, a higher consolidation coefficient value indicates a faster consolidation rate, while a lower consolidation coefficient value indicates a slower consolidation rate. The consolidation coefficient is related to the permeability, particle size and structure of the soil layer. The degree of consolidation indicates the degree to which the pore water pressure of the soil is dissipated. Generally, when the degree of consolidation reaches more than 90%, it can be considered that the consolidation process of the soil layer is basically completed.

[0026] Furthermore, the method of testing the test hole to determine the water permeability is also included: Use pumping equipment to conduct pumping tests on multiple test holes in sequence; During the pumping test, record the pumping flow rate at different time points and the corresponding water level changes in the test hole; The water permeability of the test hole is calculated based on the pumping flow rate, water level drop height and cross-sectional area of ​​the test hole.

[0027] By implementing the quantitative evaluation method of the water-stopping effect of the water-stopping curtain, preferably, a pumping device, such as a pumping well and a pump, can be installed in the test hole. Start the pumping device, continuously pump water from the borehole, and observe the water level drop, so as to facilitate recording the pumping flow and corresponding water level changes at different time points. Among them, the water permeability calculation formula is:

[0028] In the formula, is the water permeability of the test hole, is the pumping flow rate, is the cross-sectional area of ​​the test hole, The height of water level drop.

[0029] Furthermore, the method of evaluating the permeability coefficient by testing the test hole is also included: Use water pressure equipment to carry out water pressure tests on multiple test holes in sequence; During the water pressure test, record the injection flow rate and injection time at different pressures; The permeability coefficient corresponding to the test hole is calculated based on the injection flow rate, injection time, cross-sectional area of ​​the test hole and hole depth.

[0030] By implementing the quantitative evaluation method of the water-stopping effect of the water-stopping curtain, preferably, similar to the pumping test, a water pressure device is prepared. The water pressure device injects pressurized water into the formation through the test hole, and observes the pressure change during the water pressure process, so as to record the injection flow rate and injection time under different pressures. Among them, the permeability coefficient calculation formula is:

[0031] In the formula, is the permeability coefficient of the test hole, To inject flow, is the injection time, is the cross-sectional area of ​​the test hole, is the hole depth.

[0032] Furthermore, the method includes testing the test hole to evaluate the water level drop: Install water level monitoring equipment in each test hole in turn, and record the daily water level changes in the test hole within a preset period; The water level drop of the test hole is evaluated according to the water level change of the test hole.

[0033] In order to further verify the rationality of the quantitative evaluation method of the water-stopping effect of the water-stopping curtain, the present invention here takes the quantitative evaluation of the water-stopping curtain effect of a foundation pit support project as an example: The present invention divides the water-stop curtain body to be tested into six test sections. According to the water pressure test results, the water permeability of five groups is less than 10Lu, and the water permeability of one group is greater than 10Lu, specifically 12.8Lu. The permeability coefficients of the six test sections in the pumping test are all less than K≤10-5, which meets the requirements. The qualified requirements are met. The following table is an evaluation and judgment table of the water-stop curtain for a foundation pit support project of a certain project: Waterstop curtain evaluation and judgment table

[0034] It can be seen from the above table that the evaluation result obtained by the quantitative evaluation method for the water-stopping effect of the water-stop curtain of the present invention is close to the actual situation and has high accuracy, and can well guide the construction of similar projects.

[0035] The present invention also discloses an evaluation system, which is applied to the above-mentioned quantitative evaluation method of the water-stopping effect of the water-stopping curtain, comprising: Sampling module, used for drilling and sampling the water-stop curtain body to be inspected; The rock sample test module is used to test the rock samples and evaluate the drilling data of the rock samples; The test hole experimental module is used to test the test hole and evaluate the hydrological parameters of the test hole; The judgment module is used to summarize the assessed drilling data and hydrological parameters, and make a one-to-one correspondence between the summarized assessment results and the standard evaluation table for water-stop curtains; The evaluation module is used to determine the quantitative evaluation effect of the water-stop curtain body to be tested based on the judgment of the qualification of each factor in the drilling data and hydrological parameters.

[0036] It should be understood that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. For those skilled in the art, the technical solutions described in the above embodiments can be modified, or some of the technical features therein can be replaced by equivalents; and all these modifications and replacements should fall within the scope of protection of the claims attached to the present invention.

Claims

1. A quantitative evaluation method for the water-stopping effect of a water-stopping curtain, characterized in that: The quantitative evaluation method for the water-stopping effect of the water-stopping curtain includes: Selecting a water-stop curtain body to be tested, drilling and exploring the water-stop curtain body to be tested and taking samples to obtain a test hole and rock samples at a corresponding hole position; Conducting tests on the rock samples and evaluating the drilling data of the rock samples, the drilling data including compressive strength, permeability, recovery rate and consolidation condition; Conducting tests on the test hole and evaluating the hydrological parameters of the test hole, wherein the hydrological parameters include water permeability, permeability coefficient and water level drop; Summarize the assessed drilling data and hydrological parameters, and make a one-to-one correspondence between the summarized assessment results and the standard evaluation table for water-stop curtains for qualification determination; According to the borehole data and the judgment of the qualification of each factor in the hydrological parameters, the quantitative evaluation effect of the water-stop curtain body to be tested is determined.

2. The method for quantitatively evaluating the water-stopping effect of a water-stopping curtain according to claim 1 is characterized in that: The method for drilling and sampling the water-stop curtain body to be tested: Dividing the water-stop curtain body to be tested into a plurality of test sections; According to the divided test sections, drilling exploration is performed on each of the test sections, and each of the test sections includes at least three test holes; In the process of drilling exploration of each test section, taking out representative rock samples from each test hole; Each of the rock samples taken out is marked, and the hole position and hole depth of each test hole are recorded.

3. The method for quantitatively evaluating the water-stopping effect of a water-stopping curtain according to claim 2 is characterized in that: Also included is a method for testing the rock sample to determine the compressive strength: Using rock mechanics testing equipment to sequentially perform compressive strength tests on the marked plurality of rock samples; The maximum pressure of each rock sample when it is destroyed is recorded to obtain the compressive strength of the rock sample.

4. The method for quantitatively evaluating the water-stopping effect of a water-stopping curtain according to claim 2 is characterized in that: Also included is a method for testing the rock sample to determine the permeability: Using a permeability testing device to sequentially perform permeability tests on the marked plurality of rock samples; Under a preset water head pressure, the amount of water passing through the rock sample within a predetermined time is measured, and the permeability of the rock sample is calculated.

5. The method for quantitatively evaluating the water-stopping effect of a water-stopping curtain according to claim 2 is characterized in that: The method also includes testing the rock sample to determine the recovery rate: sequentially obtaining the actual sizes of the marked plurality of rock samples; The actual size of the rock sample is compared and calculated with the preset theoretical sampling size to obtain the sampling rate of the rock sample.

6. The method for quantitatively evaluating the water-stopping effect of a water-stopping curtain according to claim 2 is characterized in that: Also included is a method for testing the rock sample to assess the consolidation condition: Using a consolidation test device to sequentially perform consolidation tests on the marked plurality of rock samples; Under a preset constant load, recording the pore water pressure and volume change data of the rock sample at different time points; The consolidation coefficient and degree of consolidation of the rock sample are calculated based on the recorded pore water pressure and volume change data; The consolidation condition of the soil layer corresponding to the rock sample is evaluated according to the consolidation coefficient and the consolidation degree.

7. The method for quantitatively evaluating the water-stopping effect of a water-stopping curtain according to claim 2 is characterized in that: Also included is a method for testing the test hole to determine the water permeability: Using a pumping device to sequentially conduct a pumping test on the plurality of test holes; During the pumping test, the pumping flow rate at different time points and the corresponding water level changes in the test hole are recorded; The water permeability of the test hole is calculated according to the pumping flow rate, the water level drop height and the cross-sectional area of ​​the test hole.

8. The method for quantitatively evaluating the water-stopping effect of a water-stopping curtain according to claim 2 is characterized in that: Also included is a method for testing the test hole to determine the permeability coefficient: Using a water pressure device to sequentially perform a water pressure test on the plurality of test holes; During the water pressure test, record the injection flow rate and injection time at different pressures; The permeability coefficient corresponding to the test hole is calculated according to the injection flow rate, the injection time, the cross-sectional area of ​​the test hole, and the hole depth.

9. The method for quantitatively evaluating the water-stopping effect of a water-stopping curtain according to claim 2 is characterized in that: Also included is a method for testing the test hole to assess the water level drop: Installing water level monitoring equipment in each of the test holes in turn, and recording the daily water level changes in the test holes within a preset period; The water level drop corresponding to the test hole is evaluated according to the water level change of the test hole.

10. An evaluation system, applied to the quantitative evaluation method for water-stopping effect of water-stopping curtain according to any one of claims 1 to 9, characterized in that: The evaluation system includes: A sampling module, used for drilling and sampling the water-stop curtain body to be inspected; A rock sample test module, used to test the rock sample and evaluate the drilling data of the rock sample; A test hole experimental module, used to test the test hole and evaluate the hydrological parameters of the test hole; A determination module, for summarizing the assessed drilling data and the hydrological parameters, and making a one-to-one correspondence between the summarized assessment results and the standard evaluation table for water-stop curtains; The evaluation module is used to determine the quantitative evaluation effect of the water-stop curtain body to be tested based on the judgment of the qualification of each factor in the drilling data and the hydrological parameters.

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