Underground water distribution detection and drainage scheme design method

Abstract

The invention discloses an underground water distribution detection and drainage scheme design method, which comprises the following steps: S1, carrying out a water lifting test, preliminarily judging the water inflow of underground water in a landslide area, and determining underground water distribution in the landslide area by utilizing a landslide section layout object detection line determined by drilling; s2, according to the landslide area underground water distribution condition determined by the water lifting test and the object detection line, a hydrological test drill hole is designed; s3, a hydrological test is carried out through the hydrological test drill hole, and the underground water type and hydrogeological parameters in the landslide area are quantitatively obtained; and S4, in combination with underground water distribution and hydrogeological parameters in the landslide area, designing a layout scheme of a water collecting well and a dewatering well in a drainage project. According to the groundwater distribution detection and drainage scheme design method, blind arrangement of drainage measures is avoided, the accuracy of groundwater evaluation and the pertinence of a treatment project are effectively improved, and an effective basis is provided for exploring groundwater distribution in a landslide area and subsequent treatment projects.

Description

Technical Field

[0001] The present invention relates to the technical field of groundwater detection and engineering treatment in landslide areas, and particularly to a method for detecting groundwater distribution and designing a drainage and dewatering plan. Background Art

[0002] With the rapid development of the economy and the transportation industry, corresponding engineering activities have become more frequent, and the construction scale has gradually increased. At the same time, mountain expressways have been continuously developed. Whether in the construction process or the operation process, there are potential sliding risks for natural slopes or artificially constructed slopes. The mechanism of landslide disasters is affected by factors such as slope structure, surface and groundwater, and artificial excavation. The change of groundwater level will cause diseases such as softening of rock and soil masses, increase in soil weight, and reduction in physical and mechanical strength, thus inducing landslide diseases.

[0003] In the prior art, the geological conditions of landslides are complex, and the distribution characteristics of groundwater are difficult to distinguish, resulting in difficulties in arranging representative hydrogeological test holes (pumping holes), and thus it is impossible to accurately obtain hydrogeological parameters, hydraulic connections between different strata, groundwater seepage paths, etc. in the landslide area, directly affecting the pertinence and effectiveness of the layout of drainage and dewatering engineering measures in the landslide area. Summary of the Invention

[0004] The purpose of the present invention is to provide a method for detecting groundwater distribution and designing a drainage and dewatering plan, which clarifies the groundwater distribution characteristics in the landslide area, accurately obtains the hydrogeological parameters of the landslide area, avoids blindly arranging drainage and dewatering measures, effectively improves the accuracy of groundwater assessment and the pertinence of the treatment project, and provides an effective basis for exploring the groundwater distribution in the landslide area and subsequent treatment projects.

[0005] To achieve the above purpose, the present invention provides a method for detecting groundwater distribution and designing a drainage and dewatering plan, including the following steps:

[0006] S1. Conduct a water-lifting test to preliminarily judge the water yield of groundwater in the landslide area, arrange geophysical prospecting lines using the landslide section determined by drilling, and then determine the groundwater distribution in the landslide area;

[0007] S2. Design hydrogeological test boreholes according to the groundwater distribution in the landslide area determined by the water-lifting test and the geophysical prospecting lines;

[0008] S3. Conduct hydrogeological tests through the hydrogeological test boreholes to quantitatively obtain the groundwater types and hydrogeological parameters in the landslide area;

[0009] S4. Combine the groundwater distribution and hydrogeological parameters in the landslide area to design the layout scheme of catch wells and precipitation wells in the drainage and dewatering project.

[0010] Preferably, in step S1, the determination data of the stable water level of the borehole is obtained through drilling, and combined with the landslide section, a hydraulic gradient distribution map is drawn.

[0011] Preferably, in step S2, a plurality of hydrogeological test boreholes are arranged at representative positions in the landslide area.

[0012] Preferably, in step S3, the types of groundwater include seepage paths and hydraulic connections between strata, and the hydrogeological parameters include permeability coefficient, water inflow, and influence radius.

[0013] Preferably, in step S3, the hydrogeological test is specifically as follows:

[0014] Two observation lines perpendicular to each other in the horizontal direction are set in each hydrogeological test borehole. A plurality of observation holes are set with the hydrogeological test borehole as the center. The distances between the observation holes on each observation line and the hydrogeological test borehole are set to five meters, ten meters, and twenty meters. A steady flow pumping test and an unsteady flow pumping test are carried out using the hydrogeological test borehole. Combining the water level changes of the observation holes during the test, the type of groundwater is judged, and the hydrogeological parameters of the landslide area are calculated.

[0015] Preferably, in step S4, the layout scheme of the sump and the dewatering well in the designed drainage project is specifically as follows:

[0016] A number of sumps are arranged in the areas where groundwater is rich or seepage recharge is rapid in the landslide area, and a number of dewatering wells are arranged in the areas between the sumps or near the sumps.

[0017] Preferably, the determination method for the areas where groundwater is rich or seepage recharge is rapid in the landslide area is as follows: According to the type of groundwater and hydrogeological parameters, select the positions that cut off the groundwater flow direction and have a large water inflow, or the positions with a large water inflow and in the groundwater flow direction.

[0018] Preferably, the number of the dewatering wells is greater than the number of the sumps.

[0019] Preferably, multiple layers of inclined drainage holes are arranged inside the sump.

[0020] Therefore, by adopting the above method for detecting groundwater distribution and designing a drainage scheme, the beneficial effects of the present invention are as follows:

[0021] (1) Based on the drilled boreholes, the present invention conducts a water lifting test to qualitatively judge the groundwater richness in different areas of the landslide. Furthermore, using the landslide section formed by the boreholes, geophysical exploration lines are arranged to further determine the groundwater distribution in the landslide area. Combining the stable water levels in the boreholes in the landslide area, the groundwater distribution characteristics in the landslide area are accurately determined, and a hydraulic gradient map is drawn.

[0022] (2) The present invention combines the characteristics of groundwater distribution with the hydraulic gradient map, selects representative locations to conduct hydrogeological tests, quantitatively obtains the permeability coefficient, influence radius, hydraulic connection between different strata, and seepage path of groundwater in different parts of the landslide area, and then determines the representative and targeted layout points of the sump well and precipitation well, and verifies the good application effect of the drainage project according to the regional groundwater level monitoring.

[0023] (3) The present invention clarifies the characteristics of groundwater distribution in the landslide area, accurately obtains the hydrogeological parameters of the landslide area, avoids blindly arranging drainage measures, effectively improves the accuracy of groundwater assessment and the pertinence of the treatment project, and provides an effective basis for exploring the groundwater distribution in the landslide area and subsequent treatment projects.

[0024] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Description of the Drawings

[0025] Figure 1 is a flowchart of an embodiment of a method for detecting groundwater distribution and designing a drainage and dewatering scheme of the present invention;

[0026] Figure 2 is a water inflow diagram of an embodiment of a method for detecting groundwater distribution and designing a drainage and dewatering scheme of the present invention;

[0027] Figure 3 is a hydraulic gradient distribution diagram of an embodiment of a method for detecting groundwater distribution and designing a drainage and dewatering scheme of the present invention;

[0028] Figure 4 is a hydrogeological test hole distribution diagram of an embodiment of a method for detecting groundwater distribution and designing a drainage and dewatering scheme of the present invention;

[0029] Figure 5 is an observation hole distribution diagram of an embodiment of a method for detecting groundwater distribution and designing a drainage and dewatering scheme of the present invention;

[0030] Figure 6 is an influence radius distribution diagram of an embodiment of a method for detecting groundwater distribution and designing a drainage and dewatering scheme of the present invention;

[0031] Figure 7 is a drainage and dewatering engineering measure distribution diagram of an embodiment of a method for detecting groundwater distribution and designing a drainage and dewatering scheme of the present invention.

[0032] Reference Signs

[0033] 1, pumping well; 2, observation well; 3, sump well; 4, precipitation well. Detailed Embodiments

[0034] The technical solution of the present invention will be further described below with reference to the accompanying drawings and embodiments.

[0035] Unless otherwise defined, the technical terms or scientific terms used in the present invention shall have the ordinary meanings understood by those of ordinary skill in the field to which the present invention pertains.

[0036] Example 1

[0037] As Figure 1 shown, a method for detecting groundwater distribution and designing a drainage scheme includes the following steps:

[0038] S1. Conduct a water-lifting test using the existing boreholes in the landslide area to preliminarily judge the water inflow of groundwater in the landslide area. Layout geophysical exploration lines based on the cross-sections determined by engineering geological drilling (referred to as drilling), and then determine the groundwater distribution in the landslide area, specifically as follows:

[0039] Preliminarily judge the water inflow at different positions in the landslide area through the water-lifting test, as Figure 2 shown. Layout geophysical exploration lines based on the landslide cross-section determined by drilling, and combine the measurement data at the stable water level of the boreholes obtained from drilling to further determine the groundwater distribution in the landslide area, and draw the hydraulic gradient distribution map of the landslide area, as Figure 3 shown. It can be seen from Figure 3 that the green and light green areas are the main distribution areas of groundwater in the landslide area.

[0040] S2. Design a hydrogeological test borehole (pumping hole 1) according to the groundwater distribution in the landslide area determined by the water-lifting test and the geophysical exploration lines, specifically as follows:

[0041] According to the determined groundwater distribution in the landslide area and the hydraulic gradient distribution map, select representative positions in the green or light green areas of the landslide area to layout multiple pumping holes 1. In this embodiment, a total of seven pumping holes 1 are laid out, as Figure 4 shown, and they are numbered CS-1, CS-2, CS-3, CS-4, CS-5, CS-6, and CS-7 respectively.

[0042] S3. Conduct a hydrogeological test through the hydrogeological test borehole to quantitatively obtain the groundwater types and hydrogeological parameters in the landslide area. The groundwater types include seepage paths and hydraulic connections between different strata, and the hydrogeological parameters include permeability coefficient, water inflow, and influence radius, specifically as follows:

[0043] In this embodiment, use the seven laid-out pumping holes 1 to expand the influence range of the pumping test and further explore the hydraulic connections between different strata, groundwater seepage paths, water volume distribution in the landslide area, and influence radius. As Figure 5As shown in the figure, two observation lines perpendicular to each other in the horizontal direction are set for each pumping well 1, namely the north-south observation line and the east-west observation line. With the pumping well 1 as the center, observation wells 2 are set. The distance between the observation well 2 and the pumping well 1 on each observation line is set to 5 meters, 10 meters, and 20 meters. According to the actual situation of the landslide area, the allowable error value of the distance setting is 2 meters.

[0044] According to the multiple water level data measured in the observation wells during the hydrogeological test, stable flow pumping tests and unsteady flow pumping tests are carried out using the hydrogeological test boreholes according to specific circumstances to judge the type of groundwater. After the test, the permeability coefficient, water inflow, and its influence radius of each pumping well 1 in the landslide area are calculated. The results of its permeability coefficient and water inflow are shown in Table 1, and its influence radius is as Figure 6 shown.

[0045] Table 1 Statistical table of permeability coefficient results

[0046]

[0047]

[0048] S4. Combining the groundwater distribution and hydrogeological parameters in the landslide area, accurately design the layout scheme of the catch wells 3 and precipitation wells 4 in the drainage project, as follows:

[0049] A number of catch wells 3 are arranged in the areas with rich groundwater or rapid seepage recharge in the landslide area, and a number of precipitation wells 4 are arranged in the areas between the catch wells 3 or near the catch wells 3. According to the type of groundwater and hydrogeological parameters, select the position that intercepts the groundwater flow direction and has a large water inflow, or the position with a large water inflow and is the groundwater flow direction. In this embodiment, as Figure 7 shown, seven groups of catch wells 3 with a diameter of 4000 mm are set in the landslide area, and multiple inclined drainage holes are arranged inside the catch wells 3. The catch wells 3 are used to reduce the sliding force of the landslide body and improve the slope stability. According to the results of Table 1 and Figure 6 it can be seen that the type of groundwater in the landslide area is that the groundwater mainly comes from the rear edge and seeps from the rear edge (south) to the front edge (north), and the groundwater storage in the northern area is rich. In order to effectively intercept the groundwater in the landslide area, the layout of the catch wells 3 and precipitation wells 4 intercepts the groundwater in two sections: five groups of catch wells 3 numbered JSJ-1, JSJ-2, JSJ-3, JSJ-6, and JSJ-7 are arranged near the rear edge position; combined with the hydraulic gradient distribution map and the water inflow in each area, additional catch wells 3 are added for the areas with rich groundwater storage (both the areas with large water inflow and the groundwater flow direction positions), so, two catch wells 3 numbered JSJ-4 and JSJ-5 are also arranged.

[0050] Due to the large size and long construction period of the catchment well 3, in order to give full play to the advantages of flexible layout and rapid rectification, fifty-eight dewatering wells 4 with a diameter of 219 mm are arranged in the areas with rich groundwater and rapid seepage recharge in the landslide. The number of dewatering wells 4 is much larger than that of the catchment well 3. By taking advantage of the more flexible dewatering wells 4 and faster construction speed, the dewatering wells 4 and the catchment well 3 jointly complete the drainage work of the groundwater in the landslide, avoiding the frequent accidents in the landslide area caused by too long construction period.

[0051] Therefore, the present invention adopts the above-mentioned method for designing a groundwater distribution detection and drainage scheme, clarifies the groundwater distribution characteristics in the landslide area, accurately obtains the hydrogeological parameters of the landslide area, avoids blindly arranging drainage measures, effectively improves the accuracy of groundwater assessment and the pertinence of the treatment project, and provides an effective basis for exploring the groundwater distribution in the landslide area and subsequent treatment projects.

[0052] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that they can still modify or equivalently replace the technical solutions of the present invention, and these modifications or equivalent replacements cannot make the modified technical solutions deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A method for groundwater distribution detection and drainage scheme design, characterized in that: The following steps are involved: S1. Carry out water extraction test to preliminarily determine the amount of groundwater in the landslide area, and lay out the detection line using the landslide section determined by drilling to determine the distribution of groundwater in the landslide area; S2. Design hydrological test boreholes based on the groundwater distribution in the landslide area determined by the water extraction test and geophysical detection lines; S3. Conduct hydrological tests through hydrological test boreholes to quantitatively obtain the groundwater type and hydrogeological parameters in the landslide area; S4. Based on the groundwater distribution and hydrogeological parameters in the landslide area, design the layout plan of the water collection wells and precipitation wells in the drainage project.

2. A method for groundwater distribution detection and drainage scheme design according to claim 1, characterized in that: In step S1, the borehole stable water level measurement data is obtained through drilling, and a hydraulic gradient distribution map is drawn in combination with the landslide section.

3. A method for groundwater distribution detection and drainage scheme design according to claim 1, characterized in that: In step S2, a plurality of hydrological test boreholes are arranged at representative locations in the landslide area.

4. A method for groundwater distribution detection and drainage scheme design according to claim 1, characterized in that: In step S3, the groundwater type includes the seepage path and the hydraulic connection between various strata, and the hydrogeological parameters include the permeability coefficient, the water yield and the influence radius.

5. The method for groundwater distribution detection and drainage scheme design according to claim 1, characterized in that: In step S3, the hydrological test is specifically: Two observation lines perpendicular to each other in the horizontal direction are set in each hydrological test borehole, and multiple observation holes are set with the hydrological test borehole as the center. The distance between the observation hole and the hydrological test borehole on each observation line is set to five meters, ten meters, and twenty meters. Steady flow pumping test and non-steady flow pumping test are carried out in the hydrological test borehole. Combined with the water level changes in the observation holes during the test, the groundwater type is judged and the hydrogeological parameters of the landslide area are calculated.

6. A method for groundwater distribution detection and drainage scheme design according to claim 1, characterized in that: In step S4, the layout scheme of the water collection well and the drainage well in the drainage project is designed, specifically: Several collection wells are arranged in areas with abundant groundwater or rapid seepage recharge within the landslide region, and several precipitation wells are arranged in areas between collection wells or near collection wells.

7. A method for groundwater distribution detection and drainage scheme design according to claim 6, characterized in that: The method for determining the area with abundant groundwater or rapid seepage recharge in the landslide area is: according to the groundwater type and hydrogeological parameters, select a location that cuts off the groundwater flow and has a large amount of water gushing out, or a location with a large amount of water gushing out and is the flow direction of groundwater.

8. A method for groundwater distribution detection and drainage scheme design according to claim 6, characterized in that: The number of the precipitation wells is greater than the number of the water collection wells.

9. A method for groundwater distribution detection and drainage scheme design according to claim 6, characterized in that: Multiple layers of upward-inclined drainage holes are arranged inside the water collection well.

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