scholarly journals A Method and Equipment for Continuously Testing the Permeability Coefficient of Rock and Soil Layers

2020 ◽  
Vol 2020 ◽  
pp. 1-6
Author(s):  
Wei Chen ◽  
Datian Cui ◽  
Meng Xu ◽  
Rongchao Xu

The water pressure test and steady-flow pumping test are still commonly used for measuring the permeability coefficient of rock and soil strata. Limited by the fact that the average value of the permeability coefficient could be obtained only by this testing method, the accuracy of the experimental results of the permeability coefficient for special rock and soil strata is not good. Therefore, a new on-site testing method and equipment for continuously measuring the permeability coefficient of rock and soil strata is studied in this paper. The method is suitable for water pressure testing in borehole and the steady-flow pumping test. The technical proposal is when the pumping test or water pressure test is carried out, the final water penetration will tend to be a stable value, and then, the high-precision current meter probe will be placed at the bottom of the pumping test hole or water pressure test hole. For the pumping test, the current meter will be lifted uniformly from the bottom of the borehole testing section to the stable water level. Meanwhile, the flow rate of a differential zone of the tested section is continuously detected. For the water pressure test, the current meter will be lifted uniformly from the bottom of the borehole test section to the top of the borehole test section, and the flow rate of the differential section will be continuously detected. Through data analysis and processing, not only the average permeability coefficient of the detected sections can be obtained but also the permeability coefficient of the differential section of the rock and soil stratum can be calculated, respectively. Furthermore, the corresponding relationship between the permeability coefficient and the detected location can be obtained. In view of the abovementioned reasons, the leaking point, the specific position, and the leakage quantity of the detected section could be found out accurately, which will improve the accuracy of the testing results obviously.

Author(s):  
Jun Zhou ◽  
Tao Deng ◽  
Guangchuan Liang ◽  
Jinghong Peng ◽  
Tian Meng ◽  
...  

Abstract Pigging techniques are widely used in the oil and gas industry. The unsteady motion of the PIG in an undulating pipe section during the pigging process after a water pressure test affects the stable operation of the pipeline and also causes a pipe rupture accident in serious cases. First, an experimental study was conducted to investigate the pigging process of air–water two phase pipe flows, and the PIG reverse movement and hydraulic pulse phenomenon were observed. Subsequently, a hydraulic transient model of the pigging process after a water pressure test was established in a dual-grid system. The model combined mass and motion equations of gas and liquid and PIG dynamic equations, considered three types of PIG motion states, namely positive movement, reverse movement and still, and used the method of characteristics to solve the equations. The model exhibits the ability for PIG tracing and hydraulic pulse prediction. It can be used to obtain the position and speed of the PIG. Finally, the field data and simulation results were compared, and the results indicated that they are essentially identical. This verified the accuracy of the model that is established in this study and the reliability of computed results and provided a reliable and effective theoretical basis for the development of field pigging plans.


2016 ◽  
Vol 722 ◽  
pp. 108-112 ◽  
Author(s):  
Jiří Pazderka ◽  
Eva Hájková

There have been many experimental measurements of the waterproofing ability and durability of concrete with a crystalline admixture but there are uncertainties about the speed of the waterproofing effect caused by the crystalline admixture. The paper describes water pressure test carried out in different time intervals during the initial phase of cement hydration. The test results have shown that the full waterproofing effect of concrete with a crystalline admixture was available approximately on the 12th day after the concrete creation.


2011 ◽  
Vol 67 (7) ◽  
pp. 1065-1077 ◽  
Author(s):  
Seong-Hui Lee ◽  
Sun-Hee Kim ◽  
Young-Ho Kim ◽  
Zhong Tao ◽  
Sung-Mo Choi

2020 ◽  
Author(s):  
Haifeng Lu ◽  
Yuan Zhang ◽  
Manman Zhang ◽  
Guifang zhang

Abstract Drainage for decreasing water pressure is one of the effective measures to prevent and control water disaster caused of coal mining above high pressure limestone aquifer. The deep limestone aquifer in Huaibei mining area generally has the characteristics of high water pressure, low permeability and uneven water abundance so it is generally difficult to meet the requirements for single-hole drainage. In order to achieve the best drainage effect and consider the requirements of engineering quantity and environmental protection, a multi-objective group hole drainage optimization model was established, which takes the minimum of single-hole flow rate and hole number as the objective function and the requirements of drainage borehole and water level control point drawdown as the constraint conditions. And the particle swarm optimization algorithm was used to solve the model. On this basis, the influence of permeability coefficient and water storage coefficient on the calculation results was discussed. The results show that the permeability coefficient and water storage coefficient have great influence on the optimization of single-hole flow rate and the number of holes. For the low permeability aquifer, measures such as using partially penetrated well, appropriately increasing the number of drainage boreholes and reducing the single-hole flow rate have good drainage effect. And the drilling work amount and total drainage amount are relatively small. These are all good layout schemes for drainage. According to the results of optimization, the drainage of a coal face in Huaibei was guided and achieved good results.


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