A Hole Arrangement Method for Minimally Invasive Grouting of the Base Course

Abstract

The present invention belongs to the field of asphalt pavement maintenance, and particularly relates to a hole layout method for micro-invasive grouting of the base layer. The technical key points are as follows: obtaining pavement structure information; determining the starting point, ending point, trend and length of the transverse crack; determining the hole layout parameters of the micro-invasive grouting construction section according to the pavement structure information; drilling and cleaning the holes; embedding grouting plugs; wherein, the pavement structure information includes the thickness of the pavement surface layer: d 面层 , the thickness of the pavement base layer: d 基层 , the thickness of the pavement sub-base layer: d 路面底基层 ; the hole layout parameters of the micro-invasive grouting construction section include the depth of the deep hole: d 深孔 , the depth of the shallow hole: d 浅孔 , the embedding depth of the deep hole plug: d 深孔堵头埋深 , the embedding depth of the shallow hole plug: d 浅孔堵头埋深 , the hole spacing between the deep hole and the shallow hole: d 孔距 , the diameters of the deep hole and the shallow hole: d 孔径 , 1 cm ≤ d 孔径 ≤ 3 cm.

Description

Technical Field

[0001] The present invention relates to the field of asphalt pavement maintenance, and specifically relates to a hole layout method for micro-invasive grouting of the base course. Background Art

[0002] With the further improvement of China's highway network, the engineering diseases that need to be treated during the operation and maintenance of highways are gradually increasing. In terms of asphalt pavement maintenance, due to the flexibility and convenience of the grouting reinforcement and repair technology, which can be applied to various complex geological conditions, it is often used for the prevention and treatment of diseases in highway subgrades, pavements, slopes, and tunnels.

[0003] The grouting process uses grouting equipment to inject the mixed grout into the pavement base course to achieve the purpose of bonding and strengthening the base course. In actual applications, due to factors such as the drilling position and depth, the grouting slurry cannot be injected in place, and the slurry may flow to other places, failing to bond the surface layer and the base course, affecting the construction effect of micro-invasive grouting, and being unfavorable for treating highway base course diseases.

[0004] In view of the defects of the above-mentioned existing technologies, the present invention develops a hole layout method for micro-invasive grouting of the base course. Summary of the Invention

[0005] The purpose of the present invention is to develop a hole layout method for micro-invasive grouting of the base course. According to the thickness of the pavement surface layer, base course, and sub-base course; according to a preset formula, determine the deep hole depth, shallow hole depth, deep hole plug burial depth, shallow hole plug burial depth, and hole distance between the deep hole and the shallow hole for the section of the road that needs to be constructed with micro-invasive grouting; according to the hole layout method, determine the micro-invasive grouting construction plan; according to the micro-invasive grouting plan, carry out micro-invasive grouting construction on the section of the road that needs to be maintained, effectively inject the slurry into the base course, achieve the treatment effect of bonding the surface layer and the base course, improve the construction effect of micro-invasive grouting, and achieve the purpose of improving the highway maintenance effect.

[0006] The above technical purpose of the present invention is achieved through the following technical solutions:

[0007] A hole layout method for micro-invasive grouting of the base course provided by the present invention includes the following operation steps: obtaining pavement structure information; determining the starting point, ending point, trend, and length of the transverse crack; determining the hole layout parameters for the section of the road that needs to be constructed with micro-invasive grouting according to the pavement structure information; drilling and cleaning the holes; embedding grouting plugs.

[0008] Among them, the pavement structure information includes the pavement surface layer thickness: d 面层 , the pavement base course thickness: d 基层 , the pavement sub-base course thickness: d 路面底基层 ;

[0009] The hole layout parameters for the section of the road that needs to be constructed with micro-invasive grouting include the deep hole depth: d 深孔, Shallow hole depth: d 浅孔 , Embedded depth of deep hole plug: d 深孔堵头埋深 , Embedded depth of shallow hole plug: d 浅孔堵头埋深 , Hole spacing between deep holes and shallow holes: d 孔距 , Bore diameters of deep holes and shallow holes: d 孔径 , 1 cm ≤ d 孔径 ≤ 3 cm.

[0010] In the present invention, the hole layout method is determined according to the road surface structure information, and a targeted hole layout scheme can be proposed for highways with different road surface structures, effectively improving the grouting effect.

[0011] Further, the depth of the deep hole is determined by the following formula: d 深孔 = d 面层 + d 基层 + d 路面底基层 / γ, and the unit names are all cm, where γ is a constant determined according to the linear regression equation between the grouting pressure and the depth of the deep hole in the road surface base course. In the present invention, the size of the grouting pressure is used to limit the depth of the deep hole. The reason is that if the depth of the deep hole is too large, a higher grouting pressure will be required to inject it into the hole, and too high a grouting pressure will damage the performance of the grouting liquid and the grouting effect; at the same time, too high a grouting pressure will also impose a burden on the grouting equipment and affect the service life of the grouting equipment; if the depth of the deep hole is too small, it cannot ensure that the grouting liquid reaches the disease location of the ground base course, also affecting the grouting effect.

[0012] Further, the linear regression equation is γ = -10a + 14, where a is the value of the grouting pressure, and its value range is 0.3 to 0.5; it should be noted that the grouting pressure in the present invention is calculated in the form of MPa. The present invention limits the position of the deep hole in the ground base course by using the grouting pressure through the linear regression equation, can determine the position of the deep hole in the ground base course for different road surface structures, and propose a targeted hole layout scheme for the grouting holes, ensuring the grouting effect.

[0013] Further, the depth of the shallow hole is determined by the following formula: d 浅孔 = d 面层 + d 基层 / β, and the unit names are all cm, where β is a constant determined according to the grouting pressure and the depth of the shallow hole in the road surface base course.

[0014] Further, the linear regression equation is: β = -3.3a + 2.95; where a is the value of the grouting pressure, and its value range is 0.3 to 0.5; it should be noted that the grouting pressure in the present invention is calculated in the form of MPa. The present invention limits the position of the shallow hole in the road base by using the grouting pressure through the linear regression equation, can determine the position of the shallow hole in the road base for different road structures, and proposes a hole layout plan for the grouting holes targeted, ensuring the grouting effect.

[0015] Further, the hole spacing is determined by the following formula: d 孔距 = d 面层 + d 基层 + 1.5d 孔径 , and the unit names are all cm.

[0016] Further, the buried depth of the deep hole plug is determined by the following formula: d 深孔堵头埋深 = d 面层+ 2d 孔径 , and the unit names are all cm.

[0017] Further, the buried depth of the shallow hole plug is determined by the following formula: d 浅孔堵头埋深 = d 面层 - 2d 孔径 , and the unit names are all cm.

[0018] Further, for the hole layout method provided by the present invention, holes are arranged from the starting point to the ending point of the transverse crack along the trend.

[0019] Further, after the hole layout parameters are determined, use a measuring ruler to measure the positions of the deep hole and the shallow hole according to the hole spacing between the deep hole and the shallow hole, mark the positions of the deep hole and the shallow hole, and mark the impact drill bit according to the depth of the deep hole, the depth of the shallow hole, the buried depth of the deep hole plug, and the buried depth of the shallow hole plug.

[0020] Further, for the drilling method provided by the present invention, mark the drill bit according to the depth of the deep hole, the depth of the shallow hole, the buried depth of the deep hole plug, and the buried depth of the shallow hole plug.

[0021] Further, the starting point, ending point, trend, and length of the transverse crack are determined by radar identification.

[0022] Further, the specific method for determining the starting point, ending point, and trend of the transverse crack by radar identification is: keep the road surface free of debris, after determining that there is no interference signal in the determined section, slowly push the hand-held ground penetrating radar to obtain the radar image inside the road surface, determine the trend and length of the transverse crack according to the image, and spray the transverse crack with paint.

[0023] Further, the drilling method provided by the present invention is to use the marked impact drill to drill the marked positions of the deep hole and the shallow hole, and stop drilling when reaching the marked position of the impact drill bit.

[0024] Furthermore, the hole arrangement method adopts an "I" shape, with deep holes and shallow holes arranged alternately.

[0025] In summary, the present invention has the following beneficial effects:

[0026] The present invention provides a method for arranging holes for minimally invasive grouting of the base layer, and determines the deep hole depth, shallow hole depth, deep hole plug burial depth, shallow hole plug burial depth, and the distance between deep holes and shallow holes of the road section that needs to be constructed by minimally invasive grouting according to the thickness of the highway surface layer, base layer, and subbase layer; and determines the minimally invasive grouting construction plan according to the hole arrangement method, and then carries out minimally invasive grouting construction. It can propose a reasonable and accurate hole arrangement method for different road surface structures, effectively inject slurry into the base layer, play a treatment effect of bonding the surface layer and the base layer, improve the construction effect of minimally invasive grouting, and achieve the purpose of improving the highway maintenance effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a flow chart of the hole arrangement method in the minimally invasive grouting process;

[0028] Figure 2 Schematic diagram of hole layout in minimally invasive grouting technology.

[0029] Reference numerals

[0030] 1 deep hole plug; 2 deep hole; 3 shallow hole plug; 4 shallow hole; 5 base layer; 6 surface layer; 7 bottom base layer. DETAILED DESCRIPTION

[0031] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined purpose of the invention, a method for arranging holes for minimally invasive grouting of a base layer proposed by the present invention, its specific implementation method, characteristics and effects are described in detail as follows.

[0032] Example 1

[0033] like Figure 1 and 2 As shown, this embodiment is for the minimally invasive grouting construction of the base layer of a certain highway transverse crack, and the hole arrangement method is to use a "one"-shaped hole arrangement from the starting point to the end point along the direction of the transverse crack. This embodiment provides a method for arranging holes for minimally invasive grouting of the base layer, which specifically includes the following steps:

[0034] S1. Determine the location of transverse cracks on the highway. Specifically, first clean the road section where minimally invasive grouting is required to keep the road surface free of debris. Next, after confirming that there is no interference signal on the road section, slowly push the handheld ground penetrating radar to obtain the internal radar image of the road surface, determine the direction and length of the transverse cracks based on the image, and spray the transverse cracks with white spray paint;

[0035] S2. Determine the hole layout positions and depths based on the thicknesses of the road surface course 6, base course 5, and sub-base course 7. Specifically, according to the "Construction Design Drawings of This Highway", it is determined that the surface course of this section is 5 cm thick SBS modified AC-16 + 7 cm thick SBS modified AC-20, the base course is 20 cm thick cement stabilized graded crushed stone, and the sub-base course is 30 cm thick cement stabilized layer (sand + crushed stone). Calculate the hole spacing between deep holes and shallow holes, the depth of deep holes, the depth of shallow holes, the embedding depth of deep hole plugs, and the embedding depth of shallow hole plugs according to the following formulas:

[0036] d 深孔 = d 面层 + d 基层 + d 路面底基层 / γ;

[0037] d 浅孔 = d 面层 + d 基层 / β;

[0038] d 浅孔堵头埋深 = d 面层 - 2d 孔径 ;

[0039] d 深孔堵头埋深 = d 面层 + 2d 孔径 ;

[0040] d 孔距 = d 面层 + d 基层 + 1.5d 孔径 ;

[0041] S3. Starting from the origin of the transverse crack, adopt an alternating layout method of "one"-shaped deep holes 2 and shallow holes 4. According to the hole spacing between deep holes 2 and shallow holes 4 calculated by the formula, use a measuring ruler to measure the spacing, and mark the layout positions of deep holes and shallow holes on the transverse crack with red spray paint;

[0042] S4. According to the depth of deep holes, the depth of shallow holes, the embedding depth of deep hole plugs, and the embedding depth of shallow hole plugs calculated by the formula, measure the lengths of the hole depth and the embedding depth from the bottom up on the impact drill bit, and wind the impact drill bit with yellow tape at the lengths of the hole depth and the embedding depth for marking;

[0043] S5. Use the impact drill wound with yellow tape to drill holes at the positions of deep holes and shallow holes marked with red spray paint, ensure that the hole diameters of deep holes and shallow holes are 2 cm, stop drilling when reaching the yellow tape winding mark on the impact drill bit. After all the positions of deep holes and shallow holes marked with red spray paint on this transverse crack are drilled, use an air gun to remove debris such as crushed stones in the holes;

[0044] S6. After the hole cleaning is completed, use yellow tape to wrap the marked drill bit and bury the grouting plugs into the deep hole and the shallow hole respectively, and stop when buried to the position marked by the yellow tape winding.

[0045] From the above technical solutions, it can be seen that the hole layout method for micro-invasive grouting of the base layer provided by the present invention includes: the depth of the deep hole, the depth of the shallow hole, the embedding depth of the deep hole plug, the embedding depth of the shallow hole plug, the hole distance between the deep hole 2 and the shallow hole 4, and the hole diameter of the deep hole 2 and the shallow hole 4. Among them, the above data can be calculated according to the formulas in the present invention, and according to the calculated hole layout method, determine the micro-invasive grouting plan for the base layer of the highway, and carry out micro-invasive grouting construction at the transverse cracks of the highway base layer.

[0046] Among them, the linear regression equations are respectively γ = -10a + 14; β = -2.35a + 2.95; where a is the value of the grouting pressure. The grouting pressure in this embodiment is 0.4 Mpa and the hole diameter is 2 cm. Substituting the above linear equations, we can get: γ = 10; β = 2.

[0047] Then: d 深孔 = d 面层 + d 基层 + d 路面底基层 / γ = 35 cm;

[0048] d 浅孔 = d 面层 + d 基层 / β = 22 cm;

[0049] d 浅孔堵头埋深 = d 面层 - 2d 孔径 = 8 cm;

[0050] d 深孔堵头埋深 = d 面层 + 2d 孔径 = 16 cm;

[0051] d 孔距 = d 面层 + d 基层 + 1.5d 孔径 = 35 cm.

[0052] Comparative Example 1

[0053] In this embodiment, conventional static pressure grouting construction is carried out for the same highway transverse crack as in Example 1. According to "The Construction Design Drawings of This Highway", it is determined that the surface layer of this section is 5 cm thick SBS modified AC-16 + 7 cm thick SBS modified AC-20, the base layer is 20 cm thick cement stabilized graded gravel, and the sub-base layer is 30 cm thick cement stabilized layer (sand + gravel).

[0054] The hole arrangement method is to adopt a "one"-shaped hole arrangement from the starting point to the ending point along the transverse crack direction, and the specific operation steps are as follows:

[0055] S1. Determine the location of the highway transverse crack disease. Specifically, first clean the section that needs to be constructed by micro-injection grouting of the base layer to keep the road surface free of debris. Next, after determining that there is no interference signal in the section, slowly push the handheld ground penetrating radar to obtain the radar image inside the road surface, determine the direction and length of the transverse crack according to the image, and spray the transverse crack with white paint;

[0056] S2. The distribution of the holes is as follows: d 孔深 = 30 cm, d 堵头埋深 = 12 cm, d 孔距 = 35 cm.

[0057] S3. Adopt a "one"-shaped hole arrangement method from the starting point of the transverse crack. According to the hole spacing, use a measuring ruler to measure the spacing, and mark the hole positions on the transverse crack with red paint;

[0058] S4. Measure the hole depth and the buried depth length from the bottom up on the impact drill bit, and wind the impact drill bit with yellow tape at the hole depth and buried depth length;

[0059] S5. Use the impact drill wound with yellow tape to drill the holes marked with red paint, ensure that the hole diameter is 2 cm, and stop drilling when reaching the yellow tape winding mark on the impact drill bit. After all the hole positions marked with red paint on this transverse crack are drilled, use an air gun to remove the gravel and other debris in the holes.

[0060] S6. After the hole cleaning is completed, use the drill bit wound with yellow tape to bury the grouting plugs into the holes respectively, and stop when burying to the yellow tape winding mark.

[0061] Performance test

[0062] Core samples are taken from the roads after grouting and curing in Example 1 and Comparative Example 1 in the same way. The sizes of the core samples are the same (diameter 10 cm, height 20 cm). According to the "JTG-E51-2009 - Test Procedures for Inorganic Bound Material Stabilized Materials in Highway Engineering", the unconfined compressive average strength and the average strength recovery rate of the grouted core samples are tested. The results are as follows:

[0063] Grouting method Average unconfined compressive strength MPa Average strength recovery rate of grouting core samples % Example 1 8.7 90.3 Comparative Example 1 5.53 82.6

[0064] It can be seen from the above data results that by adopting the hole arrangement method provided by the present application, the recovery rate of the average strength of the core samples can be improved.

[0065] The above are only the preferred embodiments of the present invention, and do not impose any form of limitation on the present invention. Although the present invention has been shown above in the preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some changes or modifications to equivalent embodiments by using the disclosed technical content within the scope of the technical solution of the present invention. However, as long as it does not depart from the content of the technical solution of the present invention, any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A hole layout method for minimally invasive grouting of the base layer, characterized in that, It includes the following operation steps: obtaining pavement structure information; determining the starting point, ending point, trend and length of transverse cracks; determining the hole layout parameters of the minimally invasive grouting construction section according to the pavement structure information; drilling and cleaning the holes; embedding grouting plugs. Among them, the road surface structure information includes the thickness of the road surface surface layer: , the thickness of the road surface base layer: , the thickness of the road surface sub-base layer: ; The hole layout parameters of the minimally invasive grouting construction section include the depth of deep holes: , the depth of shallow holes: , the buried depth of deep hole plugs: , the buried depth of shallow hole plugs: , the hole spacing between deep holes and shallow holes: , the diameters of deep holes and shallow holes: , 1 cm ≤ ≤ 3 cm; The depth of the deep hole is determined by the following formula: , the depth of the shallow hole is determined by the following formula: , the hole spacing is determined by the following formula: , the buried depth of the deep hole plug is determined by the following formula: , the buried depth of the shallow hole plug is determined by the following formula: , the unit name is cm in all cases. Among them, γ and β are constants. γ is determined according to the linear regression equation between the grouting pressure and the depth of the deep hole in the road base course; β is determined according to the linear regression equation between the grouting pressure and the depth of the shallow hole in the road base course; , ; where a is the value of the grouting pressure, and its value range is 0.3 to 0.5; for the hole layout method, the "one"-shaped layout is adopted, with deep holes and shallow holes arranged alternately.

2. The hole layout method for minimally invasive grouting of the base layer according to claim 1, characterized in that, For the described hole layout method, holes are arranged from the starting point of the transverse crack along the trend towards the ending point.

3. The hole layout method for minimally invasive grouting of the base layer according to claim 1, characterized in that, For the described drilling, marks are made on the drill bit according to the deep hole depth, shallow hole depth, deep hole plug embedding depth and shallow hole plug embedding depth.

4. The hole layout method for minimally invasive grouting of the base layer according to claim 1, characterized in that, The starting point, ending point, trend and length of the described transverse cracks are determined by radar identification.

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