Method for testing compressive static load of single pile of poured bearing platform and bottom plate

Abstract

The invention discloses a method for testing compressive static load of a single pile of a cast bearing platform and a cast bottom plate, which comprises the following steps of: 1) chiseling a circle of concrete, close to the bearing platform, of the bottom plate, and cutting off longitudinal reinforcing steel bars and transverse reinforcing steel bars anchored with the bearing platform in a reinforcing mesh of the bottom plate; (2) a static load test device is arranged, and a compression resistance static load test is carried out; (3) a plurality of outer ring grooves and inner ring grooves are dug in the side face of the circle of bottom plate and the side face of the bearing platform, and an annular water swelling strip is fixed to each ring groove; a plurality of grouting anchor sleeves with grouting holes are adopted to be connected with all longitudinal steel bars and transverse steel bars in the bottom plate steel bar mesh cut off in the first step in a one-to-one correspondence mode; (4) a circle of inner ring grouting annular pipe is pre-buried at the bottom of the side face of the bearing platform; a circle of outer ring grouting annular pipe is pre-buried at the bottom of the side face of the bottom plate; and (5) concrete, close to the bearing platform, of the bottom plate is poured again. According to the method, the workload is greatly reduced, and the structural strength and good waterproof performance can be ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of pile foundation compressive static load tests, and specifically relates to a test method for the single-pile compressive static load of a cast-in-place bearing platform and floor slab. Background Art

[0002] The conventional idea of a static load test is that after the pile foundation construction is completed, the pile head is connected to the natural ground elevation and the pile head is exposed. Strip-shaped piers are placed on both sides in the front-back direction, multiple left-right beam supports are placed on the strip-shaped piers, a counter-acting load is placed above the beam supports, a main beam in the front-back direction is provided below the beam supports, both ends of the main beam are placed on two front-back cushions, a steel backing plate is placed on the top of the pile head, and a jack is provided between the steel backing plate and the main beam. Within the specified test time, the jack is driven to measure the curve relationship between the applied load and the settlement value, and the inflection point of the curve bearing capacity is observed, so as to obtain the vertical compressive bearing capacity data of the single-pile pile body.

[0003] When the construction unit undertakes a project of a unfinished building, a new situation is encountered. Since the foundation floor structure of the undertaken project has been completed, that is, the bearing platform and floor slab have been cast above the single-pile pile body, but out of responsibility for the construction quality of the previous construction unit and the safety of the project structure, the undertaking construction unit has to conduct a secondary test on the bearing capacity of each single-pile pile body to judge whether the vertical compressive bearing capacity data of each single-pile pile body is consistent with what the previous contractor claimed.

[0004] However, difficulties are encountered in the specific operation process. The bearing platform and floor slab have been cast above the pile body, and the jack of the existing technology cannot contact the pile head, so the static load test device cannot be arranged. Therefore, it is only possible to completely break up the cast-in-place bearing platform and the concrete of the surrounding floor slab, and remove the steel cage of the bearing platform and the steel mesh of the surrounding floor slab to form a dug-out basin-shaped space to expose the pile head, and then install the static load test device. After the test is completed, it is also necessary to re-tie the steel bars and pour the concrete of the bearing platform and floor slab. Therefore, the workload is huge, the cost is high, and the material consumption is wasted; at the same time, the chiseled area of the bearing platform and floor slab is large, and the structural strength may be adversely affected after damage; moreover, it is very difficult to properly solve the problem of water leakage at the construction joint between the post-poured part and the pre-poured part. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a test method for the single-pile compressive static load of a cast-in-place bearing platform and floor slab, which can greatly reduce the workload and ensure good structural strength and waterproof performance.

[0006] The technical solution of the present invention is to provide a test method for the single-pile compressive static load of a cast-in-place bearing platform and floor slab, including the following construction steps:

[0007] 1), Chisel off the concrete around the bottom slab near the bearing platform, and cut off both the longitudinal and transverse steel bars in the bottom slab steel mesh that are anchored to the bearing platform;

[0008] 2), Install the static load test device and conduct the compressive static load test. The load applied by the jack in the static load test device, plus the self-weight of the bearing platform, minus the bottom resistance value of the bearing platform and the side friction resistance value of the bearing platform is the actual load applied by the jack on a single pile;

[0009] 3), Cut two outer ring grooves on the side of the bottom slab in a circle, and fix a ring-shaped water-swelling waterstop strip on each outer ring groove; Cut two inner ring grooves on the side of the bearing platform, and fix a ring-shaped water-swelling waterstop strip on each inner ring groove; Use a plurality of grouting anchor sleeves with grouting holes to connect one by one all the longitudinal and transverse steel bars in the bottom slab steel mesh cut off in step 1);

[0010] 4), Embed a circle of inner ring grouting annular pipes at the bottom of the side of the bearing platform; Embed a circle of outer ring grouting annular pipes at the bottom of the side of the bottom slab. There are a plurality of grout outlet holes on both the inner ring grouting annular pipes and the outer ring grouting annular pipes, and there is one or more vertical grout delivery pipes on both the inner ring grouting annular pipes and the outer ring grouting annular pipes;

[0011] 5), Re-pour the concrete around the bottom slab near the bearing platform.

[0012] After adopting the above construction steps, the test method for the single-pile compressive static load of the cast bearing platform and bottom slab of the present invention has the following advantages:

[0013] The only thing that an ordinary technician without creative ability can think of is to break the bearing platform, while the present invention creatively proposes not to break the bearing platform, thus greatly simplifying the operation process. Without damaging the bearing platform, only chisel off the concrete of the floor slab around the bearing platform in a circle and cut off the main steel bars in the bottom slab steel mesh that are anchored to the bearing platform, which can ensure accurate measurement, and the repair process is also simple. There is no need to re-bind the steel cage of the bearing platform and the steel mesh of the floor slab in a circle. Only need to quickly sleeve all the longitudinal and transverse steel bars cut off in step 1) with grouting anchor sleeves. One grouting anchor sleeve sleeves the two ends of the cut-off part of one steel bar, and then re-pour the chiseled-off circular concrete. Moreover, the grouting anchor sleeve can be grouted through at least one grouting hole to anchor the two ends of the cut-off part of the steel bar after solidification. Therefore, the labor cost and the labor intensity of workers are significantly reduced, and the re-pouring of the bearing platform concrete and the binding of the bearing platform steel cage and the bottom slab steel mesh are avoided, greatly reducing the material consumption and the project cost.

[0014] Through the above reasonable and relatively simple means, the construction joint at the chiseled-off part of the bottom slab during the static load test is effectively restored, and the connection between the bearing platform and the bottom slab is well repaired, ensuring that the single pile, bearing platform and bottom slab after the test have sufficient strength and good integrity.

[0015] Due to the simultaneous installation of water-swelling waterstops fixed on multiple channels such as two outer ring grooves, water-swelling waterstops fixed on multiple channels such as two inner ring grooves, and two inner and outer grouting annular pipes or supplementary grouting pipes embedded, the double waterproof facilities achieve a double insurance for water stoppage, improve the waterproof guarantee, and ensure good waterproof performance.

[0016] Furthermore, the cut-off lengths of adjacent longitudinal steel bars and adjacent transverse steel bars are different. After adopting the above construction steps, the cut-off positions of adjacent steel bars are staggered, ensuring the strength of the steel bar connection after the test and further ensuring that the single pile, pile cap, and base plate after the test have sufficient strength and good integrity.

[0017] Furthermore, the test method for the single-pile compressive static load of the already cast pile cap and base plate of the present invention further includes the following construction steps: Before re-casting the concrete around the pile cap of the base plate, first dig a groove with a larger upper part and a smaller lower part in a circle around the pile cap on the surface to be cast. Then, chisel an inner ring groove on the side surface of the pile cap in the groove, fix a ring-shaped water-swelling waterstop on this inner ring groove, and set multiple anchor bars on the four side surfaces of the pile cap in the groove. Then, pour the groove concrete and the concrete around the pile cap of the re-cast base plate at one time. In the prior art for undertaking unfinished building projects, even if the pile cap is demolished, the waterproof problem of the concrete at the new-old joint cannot be well solved. After adopting the above construction steps, the present invention digs a groove with a larger upper part and a smaller lower part at the bottom elevation of the re-cast concrete, that is, on the surface to be cast, which is convenient for excavation. Digging out the groove exposes more area on the side of the pile cap, facilitating the setting of anchor bars, tying the reinforced concrete in the groove, and integrating it with the re-cast concrete. And a water-swelling waterstop is added on the wall of the pile cap in the groove, that is, there are three water-swelling waterstops on the side surface of the pile cap in total, further enhancing the water-stopping effect at the joint between the pile cap and the re-cast concrete or post-cast concrete; and the post-cast concrete and the concrete in the dug groove are poured synchronously, forming a ring of reinforced concrete with a cross-section of a larger upper part and a smaller lower part at the joint and below the pile cap and the post-cast concrete, specifically strengthening the originally weak inner side of the post-cast concrete and the joint with the pile cap, further ensuring that the single pile, pile cap, and base plate after the test have sufficient strength and good integrity, and better solving the waterproof problem of the concrete at the new-old joint, with better waterproof effect.

[0018] Furthermore, the cross-section of the groove is a wedge shape or a trapezoid with a larger upper part and a smaller lower part. After adopting the above specific shape for the cross-section of the groove, the excavation is more convenient, and the strength of the solidified concrete is better.

[0019] Furthermore, the concrete grade of the re-poured bottom slab near the bearing platform and the concrete in the casting trench is higher than that of the original concrete in the bearing platform and the bottom slab, and it is micro-expansion concrete. After adopting the above construction steps, by pouring high-grade and micro-expansion concrete, such as the concrete grade of the post-cast concrete being one grade higher than that of the original concrete in the bearing platform and the bottom slab, the bonding strength and impermeability between the new and old concretes are greatly improved, and further ensure that the single pile, bearing platform and bottom slab after the test have sufficient strength and good integrity. Description of the Drawings

[0020] Figure 1 It is a schematic structural diagram of the cast bearing platform, bottom slab and the soil body covering the single pile to be tested in the preferred embodiment of the method of the present invention.

[0021] Figure 2 is Figure 1 The structural schematic diagram after chiseling the original concrete in

[0022] Figure 3 is Figure 2 The structural schematic diagram after arranging the static load test device in Figure 1 .

[0023] Figure 4 is Figure 2 The structural schematic diagram after arranging the static load test device in Figure 2 .

[0024] Figure 5 is along Figure 2 The vertical section shows the structural schematic diagram after excavating the trench and arranging waterproof devices such as waterstop strips and grouting pipes and arranging steel bars after the test.

[0025] Figure 6 is Figure 5 The enlarged structural schematic diagram of A in

[0026] Figure 7 is Figure 5 The structural schematic diagram after pouring the concrete in the trench and the post-cast concrete (still a vertical sectional view).

[0027] As shown in the figure:

[0028] 1. Static load test device, 11. Single pile, 12. Strip-shaped pier, 13. Bracket beam, 14. Loading material, 15. Main beam, 16. Steel backing plate, 17. Jack;

[0029] 2. Bottom slab, 21. Steel mesh, 211. Longitudinal steel bar, 212. Transverse steel bar, 213. Rectangular hole, 22. Knife edge, 23. Outer ring groove, 24. Bottom plane, 25. Original concrete;

[0030] 3. Bearing platform, 31. Inner ring groove, 32. Rebar implantation, 33. Steel reinforcement cage;

[0031] 4. Annular water-swellable waterstop strip;

[0032] 5. Grout anchor sleeve, 51. Grouting hole;

[0033] 61. Inner ring grouting annular pipe, 62. Inner vertical grout delivery pipe, 621. First plug, 63. Outer ring grouting annular pipe, 64. Outer vertical grout delivery pipe, 641. Second plug;

[0034] 71. Post-cast concrete, 72. Groove concrete;

[0035] 8. Groove;

[0036] 9. Soil mass. Detailed implementation manners

[0037] The following further describes the detailed implementation manners of the present invention with reference to the accompanying drawings. It should be noted here that the description of these detailed implementation manners is used to help understand the present invention, but does not constitute a limitation to the present invention. In addition, the technical features involved in the following detailed implementation manners of the present invention can be combined with each other as long as they do not conflict with each other.

[0038] As shown in Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 and Figure 7 .

[0039] It is not difficult to understand that for the static load test device 1 and the specific test process of single-pile compressive static load using this test device, except for the bearing platform 3 and the bottom plate 2 involved in the present invention, the rest are prior arts. For example, the static load test device 1 can be that on the ground surface on both sides of the bearing platform 3 at the top of the single pile 11, which is the bottom plate 2 in the present invention, strip-shaped piers 12 are placed in the front-back direction. Multiple cross beams 13 are placed on the strip-shaped piers 12. A reaction force load 14 is placed above the cross beams 13. A main beam 15 is provided below the cross beams 13, and both ends of the main beam 15 are placed on two front-back cushions (the cushions are not shown in the figure). It is not difficult to understand that the strip-shaped piers 12, cross beams 13, main beam 15 and cushions are all made of steel, such as section steel. The load 14 is a precast concrete block or an iron ingot, etc. On the top of the pile head, which is the top of the bearing platform 3 in the present invention, a steel backing plate 16 is placed, and a jack 17 is provided between the steel backing plate 16 and the main beam 15. The specific test process of single-pile compressive static load can be that within the specified test time, the jack 17 is driven to measure the curve relationship between the applied load and the settlement value, and the inflection point of the curve bearing capacity is observed, so as to obtain the vertical compressive bearing capacity data of the single pile 11 pile body.

[0040] Preferred embodiments of the test method for the single-pile compressive static load of a cast-in-place bearing platform and a floor slab include the following construction steps:

[0041] 1) Chisel off the concrete around the floor slab 2 adjacent to the bearing platform 3, and cut off both the longitudinal reinforcement bars 211 and transverse reinforcement bars 212 in the floor slab steel mesh 21 that are anchored to the bearing platform 3. This ring of concrete can be referred to as the original concrete 25.

[0042] 2) Arrange the static load test device 1 and conduct the compressive static load test. The load applied by the jack 17 in the static load test device, plus the self-weight of the bearing platform 3, minus the bottom resistance value of the bearing platform 3 and the side friction resistance value of the bearing platform is the actual load applied by the jack 17 on the single pile 11. The self-weight of the bearing platform 3 can also be expressed as the self-weight value of the bearing platform 3.

[0043] 3) Cut multiple, such as two, outer ring grooves 23 on the side of the floor slab 2 in a circle, and fix a ring-shaped water-swelling waterstop strip 4 on each outer ring groove 23. Cut multiple, such as two, inner ring grooves 31 on the side of the bearing platform 3, and fix a ring-shaped water-swelling waterstop strip 4 on each inner ring groove 31. Use a plurality of grouting anchor sleeves 5 provided with grouting holes 51 to connect all the longitudinal reinforcement bars 211 and transverse reinforcement bars 212 in the floor slab steel mesh 21 cut off in step 1) in a one-to-one correspondence. The plurality of grouting holes 51, such as each grouting anchor sleeve 5 is provided with two grouting holes 51. Here, the plurality in the plurality of grouting anchor sleeves 5 can be dozens or several.

[0044] 4) Embed a ring of inner ring grouting annular pipes 61 at the bottom of the side of the bearing platform 3. Embed a ring of outer ring grouting annular pipes 63 at the bottom of the side of the floor slab 2. Both the inner ring grouting annular pipes 61 and the outer ring grouting annular pipes 63 have a plurality of grouting holes (not shown in the figure). Both the inner ring grouting annular pipes 61 and the outer ring grouting annular pipes 63 have one or more vertical grouting pipes. For example, a ring of inner ring grouting annular pipes 61 is connected to an inner vertical grouting pipe 62, and the top can be sealed with a first plug 621 when not in use; a ring of outer ring grouting annular pipes 63 is connected to an outer vertical grouting pipe 64, and the top can be sealed with a second plug 641 when not in use. It is not difficult to understand that the top of the vertical grouting pipe can be connected to the grout source on the ground surface, and the bottom end is connected to the grouting annular pipe. The plurality in the plurality of grouting holes can be understood as dozens or several, one hundred and dozens or several, etc., or can be referred to as several, a plurality or several grouting holes, and are all distributed along the length of a ring and the circumference of each annular pipe.

[0045] 5) Re-pour the concrete around the floor slab 2 adjacent to the bearing platform 3, which can be referred to as the post-cast concrete 71.

[0046] The cut-off lengths of adjacent longitudinal steel bars 211 and adjacent transverse steel bars 212 may be different. Expanding on this, it means that the cut-off lengths of adjacent longitudinal steel bars 211 are different, and the cut-off lengths of adjacent transverse steel bars 212 are also different. The different cut-off lengths of adjacent longitudinal steel bars 211 and adjacent transverse steel bars 212 mean staggered cutting, which can also be understood as the cutting edges 22 of the cut-off adjacent longitudinal steel bars 211 not being on the same straight line, and the cutting edges 22 of the cut-off adjacent transverse steel bars 212 not being on the same straight line either.

[0047] In a preferred embodiment of the test method for the single-pile compressive static load of the already cast pile cap and base plate of the present invention, the following construction steps are further included: Before re-casting the concrete around the pile cap 3 in the base plate 2, that is, before casting the post-cast concrete 71, first dig a grooved channel 8 with a larger upper part and a smaller lower part in a circle around the pile cap 3 on the top surface of the bottom plane 24 to be cast, which can be called the bottom plane 24 of the pit or the top surface of the soil body 9. Then, chisel an inner ring groove 31 on the side surface of the pile cap 3 in the grooved channel 8, that is, there are three inner ring grooves 31 on the side surface of the pile cap 3 in total. Fix a ring-shaped water-swelling waterstop strip 4 on this inner ring groove 31, and set a plurality of anchor bars 32 on the four side surfaces of the pile cap 2 in the grooved channel 8. Then, cast the grooved channel concrete 72 and the concrete around the pile cap 3 in the re-cast base plate 2, that is, the post-cast concrete 71 at one time. The bottom plane 24 can also be called the casting bottom surface.

[0048] The cross-section of the grooved channel 72 can be a wedge shape or a trapezoid with a larger upper part and a smaller lower part.

[0049] The grades of the concrete around the pile cap 3 in the re-cast base plate 2, that is, the post-cast concrete 71, and the concrete for casting the grooved channel, that is, the grooved channel concrete 72, can be higher than the grade of the originally cast concrete of the pile cap 3 and the base plate 2, and can be slightly expanding concrete. For example, the grades of the grooved channel concrete 72 and the post-cast concrete 71 are one concrete grade higher than the original concrete 25 of the pile cap 3 and the base plate 2: the grade of the original concrete 25 of the pile cap 3 and the base plate 2 is C35P8, and the concrete grades of the grooved channel concrete 72 and the post-cast concrete 71 are slightly expanding C40P8.

[0050] It is not difficult to understand that the specific operations of each step of the above construction method are all convenient and practical. For example, according to the existing construction drawings, the boundary between the already cast pile cap 3 and the base plate 2 can be determined. Also, the self-weight value of the pile cap to be added, the pile cap bottom resistance value to be subtracted, and the pile cap side friction resistance value can be obtained by the following calculation methods: The volume of the pile cap multiplied by the unit weight of reinforced concrete is the self-weight value of the pile cap; the bottom area of the pile cap multiplied by the characteristic value of the bearing capacity of the foundation soil is the pile cap bottom resistance value; the side area of the pile cap multiplied by the side friction resistance coefficient of the soil body is the pile cap side friction resistance value; the side friction resistance coefficient and the characteristic value of the bearing capacity of the foundation soil are obtained from on-site investigation by the surveying unit. The steel bars can be cut using a hand-held electric saw, and its cutting operation is very convenient. Although Figure 2 、 Figure 3 、 Figure 5 andFigure 6 It is shown that the longitudinal reinforcement 211 and the transverse reinforcement 212 are still in a cross-web state after being cut and are located above the circle of concrete to be removed, i.e., the original concrete 25, and the trench 4 to be dug. However, in the actual construction process, the rectangular hole 213 formed by the intersection of the longitudinal reinforcement 211 and the transverse reinforcement 212 is large enough for workers to use small or micro electric tools and hand tools for construction. For example, an electric drill, a shovel, a digging spoon and a blower can be used to easily remove the circle of concrete of the bottom plate 2 near the pedestal 3, i.e., the original concrete 25, and clean it up. The trench 8 can be further dug downwards to clean the soil in the trench 8. It is also possible to dig multiple channels, such as two outer ring grooves 23, on the side of the bottom plate 2 and multiple channels, such as three inner ring grooves 31, on the side of the pedestal 3. For another example, glue can be used to bond and fix multiple, such as four, water-expandable waterstop strips in a circle to the corresponding ring grooves. The joints of two adjacent and mutually perpendicular water-expandable waterstop strips are glued and sealed to form each circle of annular water-expandable waterstop strips 4. For another example, the inner ring grouting annular pipe 61 and the outer ring grouting annular pipe 63 can both be made of plastic pipes with a certain elasticity. Each grouting annular pipe can be connected by two 匚-shaped plastic pipes, or by four straight plastic pipes. The connection can be connected by large and small sleeves. The sleeve connection can be sealed with glue, or it can be unsealed because if grouting is required, the interface can play the same role as a plurality of slurry outlet holes. The construction of the planting reinforcement 32 is also simple. After drilling multiple horizontal holes with an electric drill, a steel bar, i.e., the planting reinforcement 32, is inserted into each hole with an interference fit. After the groove concrete 72 is poured and solidified, the planting reinforcement 32 has a good overall pulling and reinforcing effect on the groove concrete 72 and the post-cast concrete 71. The operation of the slurry anchor sleeve 5 corresponding to the connection or butt connection of the steel bars at the cutoff point, i.e., the blade 22, is also very convenient. For example, one of the steel bars is slightly bent upwards, the slurry anchor sleeve 5 is completely inserted into the steel bar, and then the steel bar is laid flat and the other steel bar at the cutoff point is inserted. During the pouring of the post-cast concrete 71, slurry enters the slurry anchor sleeve 5 through the grouting hole 51, and has a good fixing effect after solidification.

[0051] It is easy to understand that "taking over" is also called "taking over" or "taking over". The single pile 11 is also called "pile body" or "single pile body". The original steel cage 33 of the foundation 3 is still intact. The piled load 14 is also called "heavy weight body" or "balance weight block". Casting is also called "casting". The static load test is also called "static load test" or "static load test". The test is also called "experiment" or "inspection". The base plate 2 is also called "floor slab" or "floor". The grouting sleeve 5 is also called "grouting sleeve" or "grouting sleeve". The upper ring groove is also called "inside the ring groove".

[0052] Parts, structures, quantities, etc. not marked above are not shown in the drawings, and some parts are not marked in the drawings. The drawings are for illustration only. If there is any inconsistency between the drawings and the text description or between the drawings, the text description shall prevail.

[0053] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A test method for the single-pile compressive static load of a cast-in-place bearing platform and a floor slab, characterized in that: It includes the following construction steps: 1) Chisel off the concrete around the bottom slab close to the bearing platform, and cut off both the longitudinal and transverse steel bars in the bottom slab steel mesh that are anchored to the bearing platform; 2) Install the static load test device and conduct the compressive static load test. The load applied by the jack in the static load test device, plus the self-weight of the bearing platform, minus the bottom resistance value of the bearing platform and the side friction resistance value of the bearing platform is the actual load applied by the jack on a single pile; 3) Cut multiple outer ring grooves on the side of the bottom slab in a circle, and fix a ring-shaped water-swelling waterstop strip on each outer ring groove; cut multiple inner ring grooves on the side of the bearing platform, and fix a ring-shaped water-swelling waterstop strip on each inner ring groove; use multiple grouting anchor sleeves with grouting holes to connect one by one all the longitudinal and transverse steel bars in the bottom slab steel mesh cut off in step 1); 4) Embed a circle of inner ring grouting ring pipes at the bottom of the side of the bearing platform; embed a circle of outer ring grouting ring pipes at the bottom of the side of the bottom slab. There are multiple slurry outlet holes on both the inner ring grouting ring pipes and the outer ring grouting ring pipes, and there is one or more vertical slurry conveying pipes on both the inner ring grouting ring pipes and the outer ring grouting ring pipes; 5) Re-pour the concrete around the bottom slab close to the bearing platform.

2. The test method for the single-pile compressive static load of the already cast pile cap and floor slab according to claim 1, characterized in that: The cut-off lengths of adjacent longitudinal steel bars and adjacent transverse steel bars are different.

3. The test method for the single-pile compressive static load of the already cast pile cap and floor slab according to claim 1, characterized in that: It also includes the following construction steps: Before re-pouring the concrete around the bottom slab close to the bearing platform, first dig a groove with a larger upper part and a smaller lower part in a circle around the bearing platform on the bottom surface to be poured. Cut another inner ring groove on the side of the bearing platform in the groove, and fix a ring-shaped water-swelling waterstop strip on this inner ring groove. Set multiple anchor bars on the four side surfaces of the bearing platform in the groove, and then pour the groove concrete and the re-poured concrete around the bottom slab close to the bearing platform at one time.

4. The test method for the single-pile compressive static load of the already cast bearing platform and bottom plate according to claim 3, characterized in that: The cross-section of the groove is a wedge or trapezoid with a larger upper part and a smaller lower part.

5. The test method for the single-pile compressive static load of the already cast pile cap and floor slab according to claim 3, characterized in that: The grade of the re-poured concrete around the bottom slab close to the bearing platform and the concrete for pouring the groove is higher than the grade of the original poured concrete of the bearing platform and the bottom slab, and it is micro-expansion concrete.

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