Row pile and concrete wall combined support and construction method thereof

Abstract

The invention discloses a row pile and concrete wall combined support and a construction method thereof, a row pile structure, a pre-stressed anchor rod structure and a cast-in-place concrete wall structure are combined to form a combined support body, after construction of the row pile structure is completed, the cast-in-place concrete wall structure is poured on the side, close to a foundation pit, of a row pile, and the cast-in-place concrete wall structure and the row pile structure are connected through embedded steel bars; pre-stressed anchor rod through-wall steel sleeves are pre-buried in a cast-in-place concrete wall structure, after earth is excavated to the elevation of the pre-stressed anchor rods, the pre-stressed anchor rods are constructed through the steel sleeves, and after the strength of anchor rod grouting bodies meets the requirement, bearing plates are installed at orifices for direct tensioning. According to the method, traditional inter-pile sprayed concrete simple retaining walls are replaced, a steel waist beam is omitted, inter-pile soil is supported through the reinforced concrete wall, the bearing plate is directly pressed on the concrete wall, the double requirements of inter-pile supporting in row and underground water interception are met, foundation pit dewatering or a waterproof curtain does not need to be adopted, the construction efficiency is high, pollution to the surrounding environment is small, and the construction cost is low. Meanwhile, construction period is saved and cost is reduced.

Description

Technical Field

[0001] The invention belongs to the field of foundation pit support, in particular to a combined support of a pile row and a concrete wall and a construction method thereof. Background Art

[0002] In foundation pit support engineering, the combined support technology of pile row and prestressed anchor is a widely used support technology. The supporting structure of this technology adopts pile row, and the anchor pull structure adopts prestressed anchor. The anchors are connected by steel waist beams to act on the pile row and tension. The pile wall treatment measures between the pile rows usually adopt simple support of shotcrete. After the pile row is constructed, the excavation is carried out in steps. With each step of the earthwork excavation, the piles are cleaned, and the wall reinforcement is installed after the cleaning is completed, and then the concrete between the piles is sprayed. In order to reduce the lateral pressure of the pile side soil on the pile wall, the soil between the piles is usually excavated to the 1 / 2 midpoint of the pile body, and the soil between the piles is eliminated as much as possible. Then, the reinforcement is planted on the side of the pile body, and the surface steel mesh is installed to form the wall reinforcement. Then concrete is sprayed, and the spraying thickness is usually 50mm. Then the prestressed anchor is constructed according to the anchor elevation. After the anchor grouting is completed, the steel waist beam is installed. After the anchor grouting body strength meets the requirements, the anchor is tensioned. After the anchor tensioning is completed, the next earthwork excavation is carried out.

[0003] Traditional technology is suitable for situations where the soil quality is good and there is no groundwater level within the excavation depth of the foundation pit. When there is groundwater within the excavation depth of the foundation pit and the groundwater level is shallow, for deep foundation pits using pile row prestressed anchor support technology, because the shotcrete retaining wall needs to be excavated first and then shotcrete support, the recommended shotcrete retaining wall thickness, rigidity, and strength are all small, and it cannot be used as an independent water retaining structure. Without pit dewatering or water-stop curtains, the foundation pit will be affected by groundwater and cannot be safely excavated in the next step. If pit dewatering or water-stop curtains are used to pump down or block groundwater to prevent groundwater from affecting foundation pit excavation, there are the following problems: pit dewatering is easy to affect the surrounding environment, cause ground subsidence and waste water resources, and the use of water-stop curtains will increase construction period and cost.

[0004] Therefore, the shortcomings of the prior art are summarized as follows: 1. When excavating the soil between piles, if a sand and gravel layer is encountered, the flatness of the excavation surface will be poor, which will make the flatness of the shotcrete surface layer also poor, affecting the forming of the shotcrete and further affecting the strength of the shotcrete.

[0005] Second, the prestressed anchor rods must act on the piles through steel waist beams. The steel waist beams are easily deformed by collisions with excavators during foundation pit excavation, which affects the overall force of the combined support of the piles and prestressed anchor rods.

[0006] 3. When the shotcrete retaining wall between piles encounters groundwater, it is not easy to solidify, the strength is easily affected, leakage points are easily formed, and it is easy to fall, affecting construction safety; the recommended retaining wall thickness, rigidity and strength of shotcrete are all small, and it cannot be used as an independent water retaining structure. Affected by groundwater, the sprayed anchor retaining wall between piles has the defect of not being able to achieve support and water stopping at the same time.

[0007] 4. If there is groundwater within the excavation depth of the foundation pit, it is necessary to install a water-stop curtain or take measures to dewater the foundation pit, which increases costs and construction period. In addition, dewatering not only causes waste of water resources but also easily causes ground subsidence, affecting the surrounding environment. Summary of the invention

[0008] The purpose of the present invention is to provide a combined support of a pile row and a concrete wall and a construction method thereof, in order to solve the technical problem that the flatness of the soil, sand and gravel layer between the piles is poor during excavation, which makes the flatness of the shotcrete surface layer poor and affects the forming of the shotcrete, and also to solve the technical problem that the prestressed anchor rod must act on the pile row through the steel waist beam, the steel waist beam is easy to deform, and affects the overall stress of the support, and also to solve the technical problem that when the retaining wall between the shotcrete piles encounters groundwater, the strength is easily affected, leakage points are easily formed, the retaining wall cannot be used as an independent water retaining structure, and support and water stopping cannot be achieved at the same time, and also to solve the technical problem that when there is groundwater within the excavation depth range of the foundation pit, a water-stop curtain needs to be set up or foundation pit dewatering needs to be adopted, which increases the cost and construction period and affects the surrounding environment.

[0009] To achieve the above object, the present invention adopts the following technical solution: A combined support of a row of piles and a concrete wall comprises a support body, wherein the support body comprises a row of piles structure, a cast-in-place concrete wall structure and a prestressed anchor rod structure, wherein the side close to the foundation pit is the outer side, and the side close to the row of piles structure is the inner side, the row of piles structure is arranged close to the soil outside the foundation pit, and a row of piles cap beam is arranged on the top surface of the row of piles structure. The cast-in-place concrete wall structure is set close to the outer surface of the pile structure. The top surface of the cast-in-place concrete wall structure is at the same height as the pile structure. The pile crown beam is also set on the top surface of the cast-in-place concrete wall structure and widened to be flush with the outer surface of the cast-in-place concrete wall structure. The cast-in-place concrete wall structure is connected to the pile structure through the tie bars between the wall piles. The cast-in-place concrete wall structure includes wall reinforcement and wall concrete. The inner half of the tie bars between the wall piles is embedded in the pile structure, and the outer half of the tie bars between the wall piles is embedded in the wall concrete. The outer end surface of the tie bars between the wall piles is flush with the outer surface of the wall concrete. There is soil between the piles, and the cast-in-place concrete wall structure and the soil between the piles are connected by a set of prestressed anchor rod structures. The prestressed anchor rod structure includes a steel strand anchor rod, which includes, from the inside to the outside, a soil solidification section between the piles, a free section inside the wall, and an anchor head section outside the wall. The prestressed anchor structure also includes three parts of the force transmission structure formed by the steel strand anchor passing through the soil between piles and the cast-in-place concrete wall structure from the inside to the outside, namely the consolidation part in the soil between piles, the embedded part in the wall and the anchor part outside the wall. The external anchoring part of the wall includes a wedge-shaped pressure plate and an anchor. The wedge-shaped pressure plate is provided with a through-plate hole. The corresponding outer wall anchor head section is the portion of the steel strand anchor rod extending out of the outer surface of the wall concrete. The outer wall anchor head section passes through the through-plate hole and is anchored to the wedge-shaped pressure plate through an anchor.

[0010] The embedded part in the wall includes a through-wall steel sleeve, horizontal structural reinforcement ribs and a steel plate. The through-wall steel sleeve is embedded in the wall concrete obliquely upward and horizontally. The outer end of the through-wall steel sleeve is the front end, and the inner end of the through-wall steel sleeve is the rear end. The front end is higher than the rear end. The horizontal structural reinforcement ribs are fixedly connected to the upper and lower sides of the front end of the through-wall steel sleeve respectively. The through-wall steel sleeve and the horizontal structural reinforcement ribs are fixedly connected to the wall steel bars in the cast-in-place concrete wall structure. The steel plate is vertically fixedly connected to the end face of the front end of the through-wall steel sleeve. The outer surface of the steel plate is flush with the outer surface of the wall concrete. A rod hole is opened in the center of the steel plate. The corresponding free section through the wall is located in the cast-in-place concrete wall structure, where the steel strand anchor rod is placed in the through-wall steel sleeve, and the outer end of the free section through the wall passes through the through-rod hole. The consolidation part in the soil between piles includes anchor holes formed in the soil between piles along the rear end position and angle of the wall-penetrating steel sleeve. The corresponding soil solidification section between piles is the part where the steel strand anchor is placed in the anchor hole. The soil solidification section between piles and the grouting in the anchor hole form a grouting consolidation body.

[0011] The wall reinforcement includes vertical force bars arranged in pairs and horizontal ladder bars connected between each pair of vertical force bars. The wall reinforcement forms a wall reinforcement cage. Each pair of vertical force bars is arranged correspondingly on the inner and outer sides along the thickness direction of the cast-in-place concrete wall structure, including the outer wall bars and the inner wall bars. The horizontal ladder bars are arranged at intervals up and down along the height direction of the vertical force bars. The horizontal ladder bars are fixedly connected between the outer wall bars and the inner wall bars. The tie bars between the wall piles are horizontally fixedly connected to the outer and inner wall bars. The front and rear ends of the wall-penetrating steel sleeve are fixedly connected to the outer and inner wall reinforcements respectively. The two ends of the horizontal structural reinforcement are fixedly connected to the outer sides of the outer wall reinforcements on the left and right sides of the through-wall steel sleeve.

[0012] The cast-in-place concrete wall structure is set up in sections along the height direction of the support body according to the construction excavation surface, including the completed wall of the upper section and the construction wall of this layer. The bottom connecting end of the upper steel bar connecting sleeve extends downward from the corresponding vertical force-bearing reinforcement position on the bottom surface of the upper completed wall. The bottom surface of the construction wall of this layer is flush with the earth excavation surface of this layer. The steel bar connecting sleeve of this layer is pre-embedded on the earth excavation surface of this layer and at the corresponding vertical force-bearing reinforcement position, and the top connecting end of the steel bar connecting sleeve of this layer is exposed from the earth excavation surface of this layer. The upper steel bar connecting sleeve corresponds to the steel bar connecting sleeve of this layer up and down. Both ends of the vertical force-bearing reinforcement of the construction wall of this layer are threaded and are respectively threadedly connected with the top connecting end of the steel bar connecting sleeve of this layer and the bottom connecting end of the upper steel bar connecting sleeve.

[0013] The tie bars between the wall piles are arranged at intervals along the height direction of the pile row structure, and the tie bars between the wall piles on each pile row are arranged in groups along the length direction of the cast-in-place concrete wall structure. There are two rows of tie bars between the wall piles in the construction wall of this layer, namely the upper row of tie bars located at the top of the construction wall of this layer and the lower row of tie bars located at the bottom of the construction wall of this layer. The horizontal ladder reinforcement is located between the upper row of tie bars and the lower row of tie bars. A double layer of horizontal ladder reinforcement facing each other is arranged in the construction wall of this layer, namely the upper ladder reinforcement and the lower ladder reinforcement. The prestressed anchor rod structure is located between the double layers of horizontal ladder reinforcement.

[0014] When the combined support of piles and concrete walls is located below the groundwater level, a circular water-stop flange of the vertical cylinder is fixedly connected to the middle of the through-wall steel sleeve.

[0015] A construction method for combined support of pile rows and concrete walls, the construction steps are as follows: Step 1: Position the pile structure outside the foundation pit according to the design drawing requirements, and then construct the pile structure; Step 2: excavate trench sections in steps close to the side wall of the pile row, and place the wall reinforcement cage below the excavation width greater than the thickness of the cast-in-place concrete wall structure; Step 3: After the upper wall is completed, the earthwork within the scope of the current construction wall is excavated downwards, the bottom of the upper wall is chiseled to expose the bottom connection end of the upper steel bar connection sleeve, and then excavation is carried out to the bottom excavation surface of the current construction wall, that is, the earthwork excavation surface of the current layer; Step 4: Design and drill reinforcement holes on the pile body of the row pile structure for embedding tie bars between the wall piles. The reinforcement holes are located at the top and bottom of the construction wall of this layer; The anchor holes are divided into top anchor holes and bottom anchor holes. The top anchor holes are two in a row and are located 0.1m below the top elevation of the wall on this layer. The bottom anchor holes are two in a row and are located 0.1m above the bottom elevation of the wall on this layer. Step 5: bury and install the current layer of steel bar connection sleeves at the position corresponding to the upper section of steel bar connection sleeves on the current layer of earth excavation surface, and expose the top connection end thereof; Step 6: embed tie bars between the wall piles in the embedding holes, and the extension length of the tie bars between the wall piles is equal to the thickness of the cast-in-place concrete wall structure; Step 7: According to whether there is a prestressed anchor structure within the excavated soil in step 2 and the relationship with the groundwater level, the wall reinforcement cage is installed according to the situation. The upper and lower ends of the vertical force reinforcement of the wall reinforcement cage are threaded before installation, and then the lower end of the vertical force reinforcement is first threadedly connected to the current layer of reinforcement connection sleeve, and then the upper end of the vertical force reinforcement is threadedly connected to the upper section reinforcement connection sleeve; Step 8: hoist the current layer of formwork from the outside of the slot section. After the current layer of formwork is hoisted in, first install the top form reinforcement in the wall to fix the formwork, and then backfill the slag on the outside of the current layer of formwork; Step 9: After the template of this layer is installed and fixed, plug the pouring hose to the bottom of the slot section, and then pour the wall concrete. After the age and strength of the wall concrete meet the requirements, remove the template of this layer, and the construction wall of this layer becomes the completed wall of the upper section; Step 10, excavate the next section of earthwork, repeat steps 3 to 9 until the earthwork is excavated to the base elevation, until all sections are completed and the overall cast-in-place concrete wall structure is formed.

[0016] When the excavation trench section is above the groundwater level and no prestressed anchor structure is designed, In step 2, the excavation dimensions of the trench sections are as follows: Excavation length: The excavation length of each section of earthwork shall not exceed 20m; Excavation depth: shall not exceed 2m.

[0017] In step 7, the wall reinforcement cage is lowered as a whole, and the outer wall reinforcement 511 and the inner wall reinforcement 512 are respectively installed between the top connection end of the corresponding current layer reinforcement connection sleeve 10 and the bottom connection end of the upper section reinforcement connection sleeve 8; When the excavation trench section is above the groundwater level and is designed with a prestressed anchor structure, In step 2, the excavation dimensions of the trench sections are as follows: Excavation length: The excavation length of each section of earthwork shall not exceed 20m; Excavation depth: Excavate to 0.7m below the anchor elevation. In step 7, the wall reinforcement cage is lowered as a whole, and the outer wall reinforcement 511 and the inner wall reinforcement 512 are respectively installed between the top connection end of the corresponding current layer reinforcement connection sleeve 10 and the bottom connection end of the upper section reinforcement connection sleeve 8. After step 7 and before step 8, add the construction steps of prestressed anchor structure, as follows: Step a, erecting the through-wall steel sleeve in the wall steel cage in the steel plane frame according to the design elevation and the horizontal spacing requirements, controlling the inclination angle of the through-wall steel sleeve during erection, and the front end of the through-wall steel sleeve extends out of the outer wall reinforcement; Step b, welding a steel backing plate on the front end surface of the wall-penetrating steel sleeve; Step c, fixing and connecting the horizontal structural reinforcement ribs to the upper and lower sides of the through-wall steel sleeve behind the steel pad and the outer sides of the wall outer ribs on the left and right sides of the through-wall steel sleeve; Continue construction until step nine is completed. Step d, after the template is removed, the prestressed anchor structure is constructed. First, the hole of the through-wall steel sleeve is cleaned, and the prestressed anchor structure is drilled into the soil between the piles through the through-wall steel sleeve. After the drilling is completed, the steel strand anchor is placed and grouting is performed for anchoring; Step e, after the age and strength of the grouting consolidation body meet the requirements, a wedge-shaped pressure plate is installed, the steel strand anchor rod is passed through the wedge-shaped pressure plate, and then an anchor is installed to tension the steel strand anchor rod; Then in step nine, the cast-in-place concrete wall structure is first cast to 0.7m below the elevation of the prestressed anchor structure. After the construction of the prestressed anchor structure is completed, the next section of earthwork is excavated and step ten is continued.

[0018] When the excavation trench section is below the groundwater level and no prestressed anchor structure is designed, In step 2, the excavation dimensions of the trench sections are as follows: First, excavate to 0.5m above the groundwater, then use a telescopic arm grab to excavate in sections. Excavation length: each section excavation length is no more than 6m; excavation depth: no more than 2m; increase the dewatering step and dig a drainage well inside the foundation pit near the cast-in-place concrete wall structure; The construction steps for installing the wall reinforcement cage in step seven are as follows: Step f, firstly, installing the inner wall reinforcement between the top connection end of the current layer steel bar connection sleeve and the bottom connection end of the upper layer steel bar connection sleeve; Step g, then fix and connect the outer wall reinforcement and the double-layer horizontal ladder reinforcement into a whole; Step h, lower the double-layer horizontal ladder reinforcement and the outer wall reinforcement as a whole, and install the outer reinforcement between the top connecting end of the current layer's steel bar connecting sleeve and the bottom connecting end of the upper section's steel bar connecting sleeve.

[0019] When the excavation trench section is below the groundwater level and a prestressed anchor structure is designed, In step 2, the excavation dimensions of the trench sections are as follows: First, excavate to 0.5m above the groundwater, then use a telescopic arm grab to excavate in sections. Excavation length: each section excavation length is no more than 6m; excavation depth: no more than 2m; increase the dewatering step and dig a drainage well inside the foundation pit near the cast-in-place concrete wall structure; The construction steps for installing the wall reinforcement cage in step seven are as follows: Step i, firstly, the inner wall reinforcement is installed between the top connection end of the current layer steel bar connection sleeve and the bottom connection end of the upper layer steel bar connection sleeve; Step j, then fix and connect the outer wall reinforcement and the double-layer horizontal ladder reinforcement into a whole; Step k, the middle part of the barrel of the through-the-wall steel sleeve is fixedly connected to the double-layer horizontal ladder reinforcement by setting two vertical connectors, so that the through-the-wall steel sleeve is fixedly connected to the outer wall reinforcement and the double-layer horizontal ladder reinforcement into a whole; Step 1, welding a steel backing plate on the front end surface of the wall-penetrating steel sleeve; Step m, fixing and connecting the horizontal structural reinforcement ribs to the upper and lower sides of the front end of the through-wall steel sleeve behind the steel pad and the outer sides of the wall outer ribs on the left and right sides of the through-wall steel sleeve; Step n, lower the wall-penetrating steel sleeve, the outer wall reinforcement and the double-layer horizontal ladder reinforcement into the slot section as a whole, close to the inner wall reinforcement during lowering, and after lowering to the design elevation, fix the inner wall reinforcement and the upper ladder reinforcement; Continue construction until step nine is completed. Step p, after the template is removed, the prestressed anchor structure is constructed. First, the hole of the through-wall steel sleeve is cleaned, and the prestressed anchor structure is drilled into the soil between the piles through the through-wall steel sleeve. After the drilling is completed, the steel strand anchor is placed and grouting is performed for anchoring; Step q, after the age and strength of the grouting consolidation body meet the requirements, a wedge-shaped pressure plate is installed, the steel strand anchor rod is passed through the wedge-shaped pressure plate, and then an anchor is installed to tension the steel strand anchor rod; Then in step nine, the cast-in-place concrete wall structure is first cast to 0.7m below the elevation of the prestressed anchor structure. After the construction of the prestressed anchor structure is completed, the next section of earthwork is excavated and step ten is continued.

[0020] Compared with the prior art, the present invention has the following characteristics and beneficial effects: The present invention relates to a combined support technology of a pile row structure, a prestressed anchor rod structure and a pile side concrete wall.

[0021] The present invention does not need to excavate the soil between piles, nor does it need to excavate to the 1 / 2 position of the pile body. The excavation is directly carried out close to the front of the pile body, and the reinforced concrete wall on the pile side is poured after excavation, and the reinforced concrete wall on the pile side is used to replace the sprayed concrete between piles.

[0022] The prestressed anchor tensioning structure of the present invention does not need to be provided with a steel waist beam, and the steel waist beam method of the traditional pile prestressed anchor support is eliminated. A steel sleeve is pre-buried in the wall, and the prestressed anchor can be bored through the steel sleeve. A steel pad can be installed at the hole of the steel sleeve to directly tension the anchor, and it can be directly pressed on the concrete surface layer of the concrete wall through the pressure plate, that is, it is directly anchored on the outside of the reinforced concrete wall.

[0023] The present invention solves the technical problems that the simple shotcrete pile retaining wall in the traditional row of piles and prestressed anchor rod combined support technology is not water-stopping and is easy to fall off when groundwater exists within the excavation depth of the foundation pit, and the disadvantage that a water-stop curtain needs to be added or pit dewatering needs to be adopted when groundwater exists within the excavation depth of the foundation pit. The present invention overcomes the problems of the influence of pit dewatering on the surrounding environment of the foundation pit or the additional construction period and cost required when the water-stop curtain is adopted in the traditional technology. By arranging a pile side reinforced concrete wall on the pit side of the pile row, the concrete wall is directly used as a retaining member between the piles to achieve soil support between the piles, and the anti-seepage effect of the concrete wall can also be used to achieve the groundwater interception requirement, without the need to adopt pit dewatering or water-stop curtain on the outside, thus achieving a water-stopping effect.

[0024] The present invention is applicable to the situation where there is groundwater within the excavation depth of the foundation pit. By combining pile rows, prestressed anchor rods, and reinforced concrete walls on the pile sides into an integral support structure, the pile rows and concrete walls are used to provide lateral retaining pressure on the soil. By effectively improving the overall stiffness, overall impermeability, and support strength between piles of the retaining structure, and utilizing the stiffness, strength, and impermeability of the reinforced concrete walls themselves, the deformation of the foundation pit slope can be more effectively controlled, groundwater infiltration can be prevented, and the stability of the foundation pit can be improved. Compared with conventional technologies, the pollution to the surrounding environment is less, the safety of the foundation pit can be effectively guaranteed, and a water-stopping effect can be achieved. The construction efficiency is high, the construction period is saved, and the construction cost is reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The present invention will be further described in detail below in conjunction with the accompanying drawings.

[0026] Figure 1 It is a schematic diagram of the side view structure of the prior art.

[0027] Figure 2 It is a schematic diagram of the prior art structure viewed from above.

[0028] Figure 3 It is a side structural schematic diagram of the present invention.

[0029] Figure 4 yes Figure 3 Schematic diagram of the cross-sectional structure.

[0030] Figure 5 yes Figure 3 The longitudinal section structure schematic diagram of the position of the prestressed anchor structure is shown in FIG.

[0031] Figure 6 yes Figure 3 Schematic diagram of the longitudinal section structure where there is no prestressed anchor structure.

[0032] Figure 7 It is a structural diagram of horizontal ladder reinforcement.

[0033] Figure 8It is a structural diagram of the wall-penetrating steel sleeve and steel pad.

[0034] Fig. 9 yes Figure 8 Schematic diagram of the front view structure.

[0035] Fig.10 It is a structural schematic diagram of a wedge-shaped pressure plate.

[0036] Fig.11 yes Fig.10 Schematic diagram of the front view structure.

[0037] Fig.12 It is a schematic diagram of the structure completed in the basic construction step three of the construction method of the present invention.

[0038] Fig.13 It is a schematic diagram of the structure completed in the six basic construction steps of the construction method of the present invention.

[0039] Fig.14 It is a schematic diagram of the construction process of step seven of the first working condition of the construction method of the present invention.

[0040] Fig.15 yes Fig.14 Schematic diagram of the completed structure.

[0041] Fig.16 This is a schematic diagram of the completed structure of step nine of the first working condition of the construction method of the present invention.

[0042] Fig.17 It is a schematic diagram of the construction process of step ten of the first working condition of the construction method of the present invention.

[0043] Fig.18 It is a structural schematic diagram of the completion of construction of step c of the second working condition of the construction method of the present invention.

[0044] Fig.19 It is a structural schematic diagram of the completion of construction of step nine of the second working condition of the construction method of the present invention.

[0045] Fig. 20 This is a structural schematic diagram of the completion of construction of step e of the second working condition of the construction method of the present invention.

[0046] Fig.21 It is a schematic diagram of the construction process of step ten of the second working condition of the construction method of the present invention.

[0047] Fig. 22 It is a structural schematic diagram of the completion of step f of the third working condition of the construction method of the present invention.

[0048] Fig.23 It is a schematic diagram of the construction process of step h of the third working condition of the construction method of the present invention.

[0049] Fig.24 It is a structural schematic diagram of the completion of construction of step h of the third working condition of the construction method of the present invention.

[0050] Fig.25 It is a schematic diagram of the construction process of step n of the fourth working condition of the construction method of the present invention.

[0051] Fig.26 It is a structural schematic diagram of the completion of construction of step n of the fourth working condition of the construction method of the present invention.

[0052] Fig. 27 It is a structural schematic diagram of the completion of construction of step nine of the fourth working condition of the construction method of the present invention.

[0053] Reference numerals: 1-pile row structure, 11-pile row cap beam; 2-cast-in-place concrete wall structure, 21-completed wall of the upper section, 22-construction wall of this floor; 3-prestressed anchor rod structure, 31-through-wall steel sleeve, 311-round water-stop flange, 32-horizontal structural reinforcement, 33-steel pad, 331-through-rod hole, 34-wedge-shaped pressure plate, 341-through-plate hole, 35-anchor, 36-steel strand anchor rod, 361-soil solidification section between piles, 362-free section through the wall, 363-anchor head section outside the wall, 364-anchor rod hole; 4-tie bars between wall piles, 41-upper row tie bars, 42-lower row tie bars; 5-wall reinforcement, 51-vertical force reinforcement, 511-outer wall reinforcement, 512-inner wall reinforcement, 52-horizontal ladder reinforcement, 521-upper ladder reinforcement, 522-lower ladder reinforcement; 6-wall concrete, 7-soil between piles, 8-connecting sleeve of upper steel bar, 9-excavation surface of current earthwork, 10-connecting sleeve of current steel bar; 12-piles wall protection, 13-steel waist beam. DETAILED DESCRIPTION

[0054] For existing combined support of pile rows and prestressed anchor rods, see Figure 1-2 As shown, a pile crown beam 11 is arranged on the top of the pile row structure 1, the pile retaining wall 12 on the pile soil 7 is made of shotcrete, and the anchor structure is made of a prestressed anchor rod structure 2. The prestressed anchor rod structure 2 is driven into the pile soil 7 from the pile retaining wall 12 and is connected to the pile row structure 1 through a steel waist beam 13.

[0055] See Example Figure 3-6As shown, a combined support of a pile row and a concrete wall includes a support body, wherein the support body includes a pile row structure 1, a cast-in-place concrete wall structure 2 and a prestressed anchor rod structure 3. The side close to the foundation pit is the outer side, and the side close to the pile row structure 1 is the inner side. The pile row structure 1 is arranged close to the soil outside the foundation pit, and a pile row cap beam 11 is arranged on the top surface of the pile row structure 1.

[0056] The cast-in-place concrete wall structure 2 is arranged close to the outer surface of the pile structure 1, and the top surface of the cast-in-place concrete wall structure 2 is at the same height as the pile structure 1. The pile crown beam 11 is also arranged on the top surface of the cast-in-place concrete wall structure 2 and widened to be flush with the outer surface of the cast-in-place concrete wall structure 2. The cast-in-place concrete wall structure 2 is connected to the pile structure 1 through the tie bars 4 between the wall piles. The cast-in-place concrete wall structure 2 includes wall steel bars 5 and wall concrete 6. The inner half of the tie bars 4 between the wall piles are embedded in the pile structure 1, and the outer half of the tie bars 4 between the wall piles are buried in the wall concrete 6. The outer end faces of the tie bars 4 between the wall piles are flush with the outer surface of the wall concrete 6.

[0057] The cast-in-place concrete wall structure 2 is arranged in sections along the height direction of the support body according to the construction excavation surface, including an upper completed wall 21 and a current construction wall 22. The thickness of the cast-in-place concrete wall structure 2 is 300mm-400mm.

[0058] See also Fig.13 and Fig.17 As shown, the bottom connection end of the upper steel bar connection sleeve 8 extends downward from the bottom surface of the upper completed wall 21 at the position corresponding to the vertical force reinforcement 51, the bottom surface of the current construction wall 22 is flush with the current earth excavation surface 9, the current steel bar connection sleeve 10 is pre-buried on the current earth excavation surface 9 at the position corresponding to the vertical force reinforcement 51, and the top connection end of the current steel bar connection sleeve 10 is exposed from the current earth excavation surface 9, and the upper steel bar connection sleeve 8 corresponds to the current steel bar connection sleeve 10 up and down. In this embodiment, the upper steel bar connection sleeve 8 and the current steel bar connection sleeve 10 are both straight threaded sleeves.

[0059] See also Figure 5-6 As shown, the tie bars 4 between the wall piles are arranged at intervals along the height direction of the pile row structure 1, and the tie bars 4 between the wall piles on each row of piles are arranged in groups along the length direction of the cast-in-place concrete wall structure 2. Two rows of tie bars 4 between the wall piles are arranged in the current layer of construction wall 22, namely, an upper row of tie bars 41 located at the top of the current layer of construction wall 22 and a lower row of tie bars 42 located at the bottom of the current layer of construction wall 22. The tie bars 4 between each row of wall piles are symmetrically arranged on the left and right sides of each row of piles.

[0060] See also Figure 5-7As shown, the wall reinforcement 5 includes vertical force-bearing bars 51 arranged in pairs and horizontal ladder bars 52 connected between each pair of vertical force-bearing bars 51. The wall reinforcement 5 forms a wall reinforcement cage. Each pair of vertical force-bearing bars 51 is arranged correspondingly on the inner and outer sides along the thickness direction of the cast-in-place concrete wall structure 2, including outer wall reinforcements 511 and inner wall reinforcements 512.

[0061] The tie bars 4 between the wall piles are horizontally fixedly connected to the outer wall bars 511 and the inner wall bars 512 .

[0062] Both ends of the vertical force-bearing bars 51 of the construction wall 22 of this layer are threaded and are respectively threadedly connected to the top connecting end of the reinforcement connecting sleeve 10 of this layer and the bottom connecting end of the upper reinforcement connecting sleeve 8.

[0063] See also Figure 5-7 As shown in 15-16, the horizontal ladder bars 52 are arranged at intervals in the vertical direction of the height of the vertical force-bearing bars 51, and the horizontal ladder bars 52 are fixedly connected between the outer wall bars 511 and the inner wall bars 512. The horizontal ladder bars 52 are located between the upper row of tie bars 41 and the lower row of tie bars 42. The construction wall 22 of this layer is provided with double layers of horizontal ladder bars 52 facing each other from top to bottom, which are the upper ladder bars 521 and the lower ladder bars 522. The horizontal ladder bars 52 are a horizontal frame in the wall, in the shape of a ladder, including two longitudinal ladder main bars on both sides and a group of ladder tie bars arranged horizontally between the ladder main bars. The vertical spacing between the upper ladder bars 521 and the lower ladder bars 522 can be set to 1m.

[0064] See also Figure 5 As shown, there is inter-pile soil 7 between the pile row structures 1, and the cast-in-place concrete wall structure 2 and the inter-pile soil 7 are connected by a group of prestressed anchor rod structures 3. The prestressed anchor rod structure 3 is located between the double-layer horizontal ladder bars 52. The prestressed anchor rod structure 3 includes a steel strand anchor rod 36, which includes, from the inside to the outside, an inter-pile soil solidification section 361, a free section 362 passing through the wall, and an anchor head section 363 outside the wall.

[0065] The prestressed anchor rod structure 3 also includes a three-part force transmission structure formed by the steel strand anchor rod 36 passing through the inter-pile soil 7 and the cast-in-place concrete wall structure 2 from the inside to the outside, namely, a consolidation part in the inter-pile soil, a pre-embedded part in the wall, and an anchoring part outside the wall.

[0066] See also Figure 5-11 As shown in Figure 20, the external wall anchoring portion includes a wedge-shaped pressure plate 34 and an anchor 35, and the wedge-shaped pressure plate 34 is provided with a through-plate hole 341.

[0067] The corresponding external wall anchor head section 363 is the portion of the steel strand anchor rod 36 extending out of the outer surface of the wall concrete 6 . The external wall anchor head section 363 passes through the plate-penetrating hole 341 and is anchored to the wedge-shaped pressure plate 34 through the anchor 35 .

[0068] The embedded part in the wall includes a through-wall steel sleeve 31, a horizontal structural reinforcement rib 32 and a steel pad 33. The through-wall steel sleeve 31 is embedded in the wall concrete 6 obliquely upward and horizontally, and the inclination angle α is 15 degrees. The outer end of the through-wall steel sleeve 31 is the front end, and the inner end of the through-wall steel sleeve 31 is the rear end. The front end is higher than the rear end. The horizontal structural reinforcement rib 32 is fixedly connected to the upper and lower sides of the front end of the through-wall steel sleeve 31, and the end face of the rear end of the through-wall steel sleeve 31 is spaced from the soil 7 between the piles. The through-wall steel sleeve 31 is located in the cast-in-place concrete wall structure 2 as a whole. The through-wall steel sleeve 31 and the horizontal structural reinforcement rib 32 are both fixedly connected to the wall reinforcement 5 in the cast-in-place concrete wall structure 2. Specifically, the front end and the rear end of the through-wall steel sleeve 31 are fixedly connected to the outer wall reinforcement 511 and the inner wall reinforcement 512, respectively. The horizontal structural reinforcement ribs 32 can be arranged horizontally throughout the entire length or connected to adjacent through-wall steel sleeves 31 in sections. The two ends of the horizontal structural reinforcement ribs 32 are fixedly connected to the outer sides of the wall outer reinforcement 511 on the left and right sides of the through-wall steel sleeves 31. The steel pad 33 is vertically fixedly connected to the end surface of the front end of the through-wall steel sleeve 31. The steel pad 33 and the wall reinforcement 5 can also be fixedly connected through the horizontal structural reinforcement ribs 32, that is, the inner surface of the steel pad 33 is also fixedly connected to the horizontal structural reinforcement ribs 32. The outer surface of the steel pad 33 is flush with the outer surface of the wall concrete 6, and a through-rod hole 331 is opened in the center of the steel pad 33.

[0069] The thickness D of the steel plate 33 is 10 mm, the outer diameter H of the through-wall steel sleeve 31 is 180 mm, the through-wall steel sleeve 31 and the steel plate 33 are fully welded, the weld height is greater than 8 mm, the size of the steel plate 33 is a×a=300 mm×300 mm, and the aperture of the through-rod hole 331 is adapted to the inner diameter of the through-wall steel sleeve 31. The wall external anchoring portion includes a wedge-shaped pressure plate 34 and an anchor 35, and a through-plate hole 341 is opened on the wedge-shaped pressure plate 34. In this embodiment, the size of the wedge-shaped pressure plate 34 parallel to the side of the cast-in-place concrete wall structure 2 is b×b=300 mm×300 mm, and the size of the wedge-shaped pressure plate 34 perpendicular to the side of the cast-in-place concrete wall structure 2 is an isosceles trapezoid, and the slope β of the trapezoid is the same as the oblique angle of the through-wall steel sleeve 31, both of which are 15 degrees. The minimum thickness dimension of the top of the wedge-shaped pressure plate 34 is c=10 mm, and the side cross-section through-plate hole 341 of the wedge-shaped pressure plate 34 is located at the center of the wedge-shaped pressure plate 34, and the opening diameter m is 70 mm.

[0070] The corresponding free section 362 passing through the wall is located in the cast-in-place concrete wall structure 2 and the portion where the steel strand anchor rod 36 is inserted into the wall-penetrating steel sleeve 31 . The outer end of the free section 362 passing through the wall passes through the rod-penetrating hole 331 .

[0071] The consolidation part in the soil between piles includes an anchor hole 364 formed on the soil between piles 7 along the rear end position and angle of the wall-penetrating steel sleeve 31. The corresponding soil solidification section 361 between piles is the part where the steel strand anchor 36 is inserted into the anchor hole 364. The soil solidification section 361 between piles and the grouting in the anchor hole 364 form a grouting consolidation body.

[0072] When the combined support of the pile row and the concrete wall is located below the groundwater level, a circular water-stop flange 311 of the vertical cylinder is fixedly connected to the middle of the through-wall steel sleeve 31 .

[0073] The basic construction steps of this construction method of combined pile support and concrete wall support are as follows: Step 1: Position the pile structure 1 outside the foundation pit according to the design drawing requirements, and then construct the pile structure 1; Step 2: Use an excavator to dig trench sections in steps close to the side wall of the pile row, and place the wall reinforcement cage below the excavation width greater than the thickness of the cast-in-place concrete wall structure 2; Step 3: After the upper wall 21 is completed, the earthwork within the scope of the current construction wall 22 is excavated downwards. The bottom of the upper wall 21 is chiseled to expose the bottom connection end of the upper steel bar connection sleeve 8, and then the excavation is carried out to the bottom excavation surface of the current construction wall 22, that is, the current earthwork excavation surface 9, see Fig.12 As shown; Step 4: Design and drill reinforcement holes on the pile body of the row pile structure 1 for implanting the tie bars 4 between the wall piles. The reinforcement holes are located at the top and bottom of the construction wall 22 of this layer; The anchor holes are divided into top anchor holes and bottom anchor holes. The top anchor holes are arranged in a row of two horizontally spaced apart and are located at a height E=0.1m below the top elevation of the construction wall 22 of the current layer. The bottom anchor holes are arranged in a row of two and are located at a height F=0.1m above the bottom elevation of the construction wall 22 of the current layer. That is, the two anchor holes in each row are arranged at the same height on the corresponding row of piles and are arranged symmetrically on both sides. Step 5: bury and install the current layer steel bar connection sleeve 10 at the position corresponding to the upper section steel bar connection sleeve 8 on the current layer earthwork excavation surface 9, and expose its top connection end; Step 6: implant the wall pile tie bars 4 in the reinforcement holes. The extension length of the wall pile tie bars 4 is equal to the thickness of the cast-in-place concrete wall structure 2. Fig.13 As shown; Step 7: According to whether the excavated soil in step 2 has a prestressed anchor structure 3 and its relationship with the groundwater level, the wall reinforcement cage is installed according to the situation. The upper and lower ends of the vertical force reinforcement of the wall reinforcement cage are threaded before installation, and then the lower end of the vertical force reinforcement is firstly threadedly connected with the current layer reinforcement connection sleeve 10, and then the upper end of the vertical force reinforcement is threadedly connected with the upper section reinforcement connection sleeve 8; Step 8: hoist the current layer of formwork into the outer side of the groove section. After the current layer of formwork is hoisted in, first install the top form reinforcement in the wall to fix the formwork, and then backfill the slag outside the current layer of formwork to prevent the formwork from shifting during concrete pouring; Step 9: After the current layer of formwork is installed and fixed, plug the pouring hose to the bottom of the slot section, and then pour the wall concrete 6. After the wall concrete 6 age and strength meet the requirements, remove the current layer of formwork, see Fig.16 As shown; Step 10: The current construction wall 22 now becomes the upper completed wall 21, and the next section of earthwork is excavated. Steps 3 to 9 are repeated until the earthwork is excavated to the base elevation, until all sections are completed, and the whole cast-in-place concrete wall structure 2 is formed, see Fig.17 shown.

[0074] According to whether the prestressed anchor structure 3 is included in step 7 and the relationship with the groundwater level, the specific wall section step-by-step construction steps are also divided into four working conditions: The first working condition: when the excavation trench section is above the groundwater level and there is no prestressed anchor structure 3 in the design, In step 2, the excavation dimensions of the trench sections are as follows: Excavation length: The excavation length of each section of earthwork shall not exceed 20m; Excavation depth: not more than 2m, In step 7, the wall reinforcement cage is lowered as a whole, and the outer wall reinforcement 511 and the inner wall reinforcement 512 are respectively installed between the top connection end of the current layer reinforcement connection sleeve 10 and the bottom connection end of the corresponding upper section reinforcement connection sleeve 8, see Figure 14-15 As shown; The second working condition: when the excavation trench section is above the groundwater level and a prestressed anchor structure 3 is designed, In step 2, the excavation dimensions of the trench sections are as follows: Excavation length: The excavation length of each section of earthwork shall not exceed 20m; Excavation depth: Excavate to 0.7m below the anchor elevation. In step 7, the wall reinforcement cage is lowered as a whole, and the outer wall reinforcement 511 and the inner wall reinforcement 512 are respectively installed between the top connection end of the current layer reinforcement connection sleeve 10 and the bottom connection end of the corresponding upper section reinforcement connection sleeve 8. After step 7 and before step 8, the construction steps of the prestressed anchor structure 3 are added, which are as follows: Step a, erecting the through-wall steel sleeve 31 in the wall steel cage in the steel plane frame according to the design elevation and the horizontal spacing requirements, controlling the inclination angle of the through-wall steel sleeve 31 during erection, and the front end of the through-wall steel sleeve 31 extends out of the outer wall reinforcement 511; Step b, welding a steel backing plate 33 on the front end surface of the wall-penetrating steel sleeve 31; Step c, the horizontal structural reinforcement ribs 32 are fixedly connected to the upper and lower sides of the through-wall steel sleeve 31 behind the steel pad 33 and the outer sides of the wall outer ribs 511 on the left and right sides of the through-wall steel sleeve 31; in order to prevent the concrete from flowing into the through-wall steel sleeve 31 during concrete pouring, after the through-wall steel sleeve 31 is installed, the two ends of the through-wall steel sleeve 31 should be filled with foam, see Fig.18 As shown; Continue with the basic construction step nine, pour the wall concrete 6 and refer to Fig.19 As shown; After completing step nine, Step d, after the template is removed, the prestressed anchor structure 3 is constructed. First, the hole of the through-wall steel sleeve 31 is cleaned, and the prestressed anchor structure 3 is drilled into the soil 7 between the piles through the through-wall steel sleeve 31. After the drilling is completed, the steel strand anchor is placed and grouting is performed for anchoring; Step e: After the age and strength of the grouting consolidation body meet the requirements, the wedge-shaped pressure plate 34 is installed, the steel strand anchor rod is passed through the wedge-shaped pressure plate 34, and then the anchor 35 is installed to tension the steel strand anchor rod 36, see Fig. 20 As shown; Then in step nine, the cast-in-place concrete wall structure 2 is first cast to 0.7m below the elevation of the prestressed anchor structure 3. After the prestressed anchor structure 3 is completed, the next section of earthwork is excavated and the process continues to step ten. Fig.21 shown.

[0075] The third working condition: when the excavation trench section is below the groundwater level and no prestressed anchor structure 3 is designed, In step 2, the excavation dimensions of the trench sections are as follows: First excavate to 0.5m above the groundwater level, then use a telescopic arm grab to excavate in sections. Excavation length: each section is no more than 6m long; excavation depth: no more than 2m; add a precipitation step, and drill a drainage well inside the foundation pit near the cast-in-place concrete wall structure 2; the drainage well is to facilitate the construction of the next concrete wall to reduce the amount of groundwater gushing out from the outside during excavation.

[0076] The construction steps for installing the wall reinforcement cage in step seven are as follows: Step f, first install the inner wall reinforcement 512 between the top connection end of the current layer steel bar connection sleeve 10 and the bottom connection end of the upper section steel bar connection sleeve 8, see Fig. 22 As shown; Step g, then the outer wall reinforcement 511 and the double-layer horizontal ladder reinforcement 52 are fixedly connected into a whole, see Fig.23 shown.

[0077] Step h, lower the double-layer horizontal ladder reinforcement 52 and the outer wall reinforcement 511 as a whole, and install the outer reinforcement between the top connection end of the current layer steel bar connection sleeve 10 and the bottom connection end of the upper section steel bar connection sleeve 8, see Fig.24 shown.

[0078] The fourth working condition: when the excavation trench section is below the groundwater level and a prestressed anchor structure 3 is designed, In step 2, the excavation dimensions of the trench sections are as follows: First excavate to 0.5m above the groundwater level, then use a telescopic arm grab to excavate in sections. Excavation length: each section is no more than 6m long; excavation depth: no more than 2m; add a precipitation step, and drill a drainage well inside the foundation pit near the cast-in-place concrete wall structure 2; the drainage well is to facilitate the construction of the next concrete wall to reduce the amount of groundwater gushing out from the outside during excavation.

[0079] The construction steps for installing the wall reinforcement cage in step seven are as follows: Step i, first install the inner wall reinforcement 512 between the top connection end of the current layer steel bar connection sleeve 10 and the bottom connection end of the upper section steel bar connection sleeve 8; Step j, then fix the outer wall reinforcement 511 and the double-layer horizontal ladder reinforcement 52 into a whole; Step k, the middle part of the barrel of the wall-penetrating steel sleeve 31 is fixedly connected to the double-layer horizontal ladder reinforcement by setting two vertical connectors, and the wall-penetrating steel sleeve 31 is fixedly connected to the outer wall reinforcement 511 and the double-layer horizontal ladder reinforcement 52 into a whole; Step 1: weld a steel backing plate 33 on the front end surface of the wall-penetrating steel sleeve 31, the size of which is 300mm×300mm×10mm. The steel sleeve adopts a DN180 welded steel pipe with a wall thickness of 3mm-5mm. A circular water-stop flange 311 can be welded on the steel sleeve; Step m, the horizontal structural reinforcement ribs 32 are fixedly connected to the upper and lower sides of the front end of the through-wall steel sleeve 31 behind the steel backing plate 33 and the outer sides of the wall outer ribs 511 on the left and right sides of the through-wall steel sleeve 31; Step n, lower the wall-penetrating steel sleeve 31, the outer wall reinforcement 511 and the double-layer horizontal ladder reinforcement 52 into the slot section as a whole, close to the inner wall reinforcement 512 when lowering, and fix the inner wall reinforcement 512 with the upper ladder reinforcement 521 after lowering to the design elevation; in order to prevent the concrete from flowing into the interior of the wall-penetrating steel sleeve 31 during concrete pouring, after the wall-penetrating steel sleeve 31 is installed, foam should be filled inside the two ends of the wall-penetrating steel sleeve 31; see Figure 25-26 shown.

[0080] Continue construction until step nine is completed. Step p, after the template is removed, the prestressed anchor structure 3 is constructed. First, the hole of the through-wall steel sleeve 31 is cleaned, and the prestressed anchor structure 3 is drilled into the soil 7 between the piles through the through-wall steel sleeve 31. After the drilling is completed, the steel strand anchor is placed and grouting is performed for anchoring; Step q, after the age and strength of the grouting consolidation body meet the requirements, install the wedge-shaped pressure plate 34, pass the steel strand anchor rod through the wedge-shaped pressure plate 34, and then install the anchor 35 to tension the steel strand anchor rod 36; Continue with the basic construction step nine, pour the wall concrete 6 and refer to Fig. 27 As shown; Then in step nine, the cast-in-place concrete wall structure 2 is first cast to 0.7 m below the elevation of the prestressed anchor structure 3, and after the construction of the prestressed anchor structure 3 is completed, the next section of earthwork is excavated and step ten is continued.

[0081] When the present invention is applied, different construction methods are selected according to the working conditions of different slot sections until the construction of all supporting bodies is completed.

Claims

1. A combined support of a pile row and a concrete wall, comprising a support body, characterized in that: The support body comprises a pile row structure (1), a cast-in-place concrete wall structure (2) and a prestressed anchor rod structure (3), wherein the side close to the foundation pit is the outer side, and the side close to the pile row structure (1) is the inner side. The pile row structure (1) is arranged close to the soil outside the foundation pit, and a pile row cap beam (11) is arranged on the top surface of the pile row structure (1). The cast-in-place concrete wall structure (2) is arranged close to the outer surface of the pile row structure (1), the top surface of the cast-in-place concrete wall structure (2) is at the same height as the pile row structure (1), and the pile row cap beam (11) is also arranged on the top surface of the cast-in-place concrete wall structure (2) and widened to be flush with the outer surface of the cast-in-place concrete wall structure (2). The cast-in-place concrete wall structure (2) is connected to the row pile structure (1) via the wall pile tie bars (4). The cast-in-place concrete wall structure (2) comprises wall reinforcement bars (5) and wall concrete (6). The inner half of the wall pile tie bars (4) are embedded in the row pile structure (1), and the outer half of the wall pile tie bars (4) are embedded in the wall concrete (6). The outer end surface of the wall pile tie bars (4) is flush with the outer surface of the wall concrete (6). Between the pile row structures (1) is inter-pile soil (7), and the cast-in-place concrete wall structure (2) and the inter-pile soil (7) are connected by a group of prestressed anchor rod structures (3), the prestressed anchor rod structure (3) includes a steel strand anchor rod (36), which includes, from the inside to the outside, an inter-pile soil solidification section (361), a free section (362) penetrating the wall, and an anchor head section (363) outside the wall. The prestressed anchor rod structure (3) further comprises a three-part force transmission structure formed by the steel strand anchor rod (36) passing through the soil between piles (7) and the cast-in-place concrete wall structure (2) from the inside to the outside, namely, a consolidation part in the soil between piles, a pre-embedded part in the wall, and an anchoring part outside the wall. The external wall anchoring portion comprises a wedge-shaped pressure-bearing plate (34) and an anchor (35). The wedge-shaped pressure-bearing plate (34) is provided with a through-plate hole (341). The corresponding external wall anchor head section (363) is the portion of the steel strand anchor rod (36) extending out of the outer surface of the wall concrete (6). The external wall anchor head section (363) passes through the plate penetration hole (341) and is anchored to the wedge-shaped pressure plate (34) through the anchor (35). The embedded part in the wall comprises a through-wall steel sleeve (31), a horizontal structural reinforcement rib (32) and a steel pad (33). The through-wall steel sleeve (31) is embedded in the wall concrete (6) obliquely upward and horizontally in the front and back directions. The outer end of the through-wall steel sleeve (31) is the front end, and the inner end of the through-wall steel sleeve (31) is the rear end. The front end is higher than the rear end. The horizontal structural reinforcement rib (32) is fixedly connected to the upper and lower sides of the front end of the through-wall steel sleeve (31). The through-wall steel sleeve (31) and the horizontal structural reinforcement rib (32) are fixedly connected to the wall steel bars (5) in the cast-in-place concrete wall structure (2). The steel pad (33) is vertically fixedly connected to the end surface of the front end of the through-wall steel sleeve (31). The outer surface of the steel pad (33) is flush with the outer surface of the wall concrete (6). A rod hole (331) is opened in the center of the steel pad (33). The corresponding wall-penetrating free section (362) is a portion located in the cast-in-place concrete wall structure (2) where the steel strand anchor rod (36) is inserted into the wall-penetrating steel sleeve (31). The outer end of the wall-penetrating free section (362) passes through the rod-penetrating hole (331). The consolidation portion in the soil between piles comprises an anchor hole (364) formed on the soil between piles (7) along the position and angle of the rear end of the through-wall steel sleeve (31); the corresponding soil solidification section (361) between piles is the portion of the steel strand anchor (36) inserted into the anchor hole (364); the soil solidification section (361) between piles and the grouting in the anchor hole (364) form a grouting consolidation body.

2. The combined support of pile rows and concrete walls according to claim 1 is characterized by: The wall reinforcement (5) comprises vertical force-bearing bars (51) arranged in pairs and horizontal ladder bars (52) connected between each pair of vertical force-bearing bars (51). The wall reinforcement (5) forms a wall reinforcement cage. Each pair of vertical force-bearing bars (51) is arranged correspondingly along the inner and outer sides of the cast-in-place concrete wall structure (2) in the thickness direction, and comprises outer wall bars (511) and inner wall bars (512). The horizontal ladder bars (52) are arranged at intervals in the upper and lower directions along the height direction of the vertical force-bearing bars (51). The horizontal ladder bars (52) are fixedly connected between the outer wall bars (511) and the inner wall bars (512). The tie bars (4) between the wall piles are horizontally fixedly connected to the outer wall bars (511) and the inner wall bars (512). The front end and the rear end of the wall-penetrating steel sleeve (31) are fixedly connected to the outer wall reinforcement (511) and the inner wall reinforcement (512) respectively. The two ends of the horizontal structural reinforcement rib (32) are fixedly connected to the outer sides of the wall outer ribs (511) on the left and right sides of the wall-penetrating steel sleeve (31).

3. The combined support of pile rows and concrete walls according to claim 2 is characterized by: The cast-in-place concrete wall structure (2) is arranged in sections along the height direction of the support body according to the construction excavation surface, including the upper section completed wall (21) and the current construction wall (22). The bottom connection end of the upper steel bar connection sleeve (8) extends downward from the bottom surface of the upper completed wall (21) at a position corresponding to the vertical force reinforcement (51); the bottom surface of the current construction wall (22) is flush with the current earth excavation surface (9); a current steel bar connection sleeve (10) is pre-buried at a position corresponding to the vertical force reinforcement (51) on the current earth excavation surface (9); the top connection end of the current steel bar connection sleeve (10) is exposed from the current earth excavation surface (9); the upper steel bar connection sleeve (8) corresponds to the current steel bar connection sleeve (10) in upper and lower positions; both ends of the vertical force reinforcement (51) of the current construction wall (22) are threaded and respectively threadedly connected to the top connection end of the current steel bar connection sleeve (10) and the bottom connection end of the upper steel bar connection sleeve (8).

4. The combined support of pile rows and concrete walls according to claim 3 is characterized by: The tie bars (4) between the wall piles are arranged at intervals along the height direction of the pile row structure (1), and the tie bars (4) between the wall piles on each pile row are arranged in groups along the length direction of the cast-in-place concrete wall structure (2). Two rows of tie bars (4) between wall piles are arranged in the construction wall (22) of the current layer, namely an upper row of tie bars (41) located at the top of the construction wall (22) of the current layer and a lower row of tie bars (42) located at the bottom of the construction wall (22) of the current layer. The horizontal ladder reinforcement (52) is located between the upper row of tie reinforcements (41) and the lower row of tie reinforcements (42). The construction wall (22) of this layer is provided with two layers of horizontal ladder reinforcements (52) facing each other, namely, the upper layer of ladder reinforcements (521) and the lower layer of ladder reinforcements (522). The prestressed anchor rod structure (3) is located between the two layers of horizontal ladder reinforcements (52).

5. The combined support of pile rows and concrete walls according to claim 4 is characterized in that: When the combined support of the pile row and concrete wall is located below the groundwater level, a circular water-stop flange (311) of the vertical cylinder is fixedly connected to the middle of the through-wall steel sleeve (31).

6. A construction method for combined support of pile rows and concrete walls according to any one of claims 1 to 5, characterized in that , the construction steps are as follows: Step 1: Position the pile row structure (1) outside the foundation pit according to the design drawing requirements, and then construct the pile row structure (1); Step 2: excavating trench sections in steps close to the side wall of the pile row, with the excavation width being greater than the thickness of the cast-in-place concrete wall structure (2) and placing the wall reinforcement cage below; Step 3: After the construction of the upper completed wall (21) is completed, the earthwork within the range of the current construction wall (22) is excavated downwards, the bottom of the upper completed wall (21) is chiseled to expose the bottom connection end of the upper steel bar connection sleeve (8), and then excavation is carried out to the bottom excavation surface of the current construction wall (22), that is, the current earthwork excavation surface (9); Step 4: Design and drill reinforcement holes on the pile bodies of the row pile structure (1) for implanting tie bars (4) between the wall piles, and the reinforcement holes are located at the top and bottom of the construction wall (22) of this layer; The reinforcing bar holes are divided into top reinforcing bar holes and bottom reinforcing bar holes. The top reinforcing bar holes are two in a row and are located 0.1 m below the top elevation of the wall (22) of the current layer. The bottom reinforcing bar holes are two in a row and are located 0.1 m above the bottom elevation of the wall (22) of the current layer. Step 5: bury and install the current layer steel bar connection sleeve (10) at a position corresponding to the upper section steel bar connection sleeve (8) on the current layer earthwork excavation surface (9), and expose its top connection end; Step 6: implant the wall pile tie bars (4) in the reinforcement holes, wherein the protruding length of the wall pile tie bars (4) is equal to the thickness of the cast-in-place concrete wall structure (2); Step 7: According to whether the excavated soil in step 2 has a prestressed anchor structure (3) and its relationship with the groundwater level, the wall reinforcement cage is installed according to the situation. The upper and lower ends of the vertical force reinforcement of the wall reinforcement cage are threaded before installation. Then, the lower end of the vertical force reinforcement is firstly threadedly connected to the current layer reinforcement connection sleeve (10), and then the upper end of the vertical force reinforcement is threadedly connected to the upper section reinforcement connection sleeve (8); Step 8: hoist the current layer of formwork from the outside of the slot section. After the current layer of formwork is hoisted in, first install the top form reinforcement in the wall to fix the formwork, and then backfill the slag on the outside of the current layer of formwork; Step nine, after the current layer of formwork is installed and fixed, the pouring hose is plugged to the bottom of the groove section, and then the wall concrete (6) is poured. After the age and strength of the wall concrete (6) meet the requirements, the current layer of formwork is removed, and the current layer of construction wall (22) now becomes the upper section of the completed wall (21); Step 10, excavate the next section of earthwork, repeat steps 3 to 9 until the earthwork is excavated to the base elevation, until all sections are constructed and the whole cast-in-place concrete wall structure (2) is formed.

7. The construction method of combined support of pile rows and concrete walls according to claim 6 is characterized by: When the excavation trench section is above the groundwater level and no prestressed anchor structure (3) is designed, In step 2, the excavation dimensions of the trench sections are as follows: Excavation length: The excavation length of each section of earthwork shall not exceed 20m; Excavation depth: not more than 2m, In step seven, the wall reinforcement cage is lowered as a whole, and the outer wall reinforcement 511 and the inner wall reinforcement 512 are respectively installed between the top connecting end of the corresponding current layer reinforcement connection sleeve 10 and the bottom connecting end of the upper section reinforcement connection sleeve 8.

8. The construction method of combined support of pile rows and concrete walls according to claim 6 is characterized by: When the excavation trench section is above the groundwater level and is designed with a prestressed anchor structure (3), In step 2, the excavation dimensions of the trench sections are as follows: Excavation length: The excavation length of each section of earthwork shall not exceed 20m; Excavation depth: Excavate to 0.7m below the anchor elevation. In step 7, the wall reinforcement cage is lowered as a whole, and the outer wall reinforcement 511 and the inner wall reinforcement 512 are respectively installed between the top connection end of the corresponding current layer reinforcement connection sleeve 10 and the bottom connection end of the upper section reinforcement connection sleeve 8. After step 7 and before step 8, the construction steps of the prestressed anchor structure (3) are added, which are as follows: Step a, erecting the through-wall steel sleeve (31) in the wall steel cage in the steel plane frame according to the design elevation and the horizontal spacing requirements, and controlling the inclination angle of the through-wall steel sleeve (31) during the erection, so that the front end of the through-wall steel sleeve (31) extends out of the outer wall reinforcement (511); Step b, welding a steel backing plate (33) on the front end surface of the wall-penetrating steel sleeve (31); Step c, fixing the horizontal structural reinforcement ribs (32) to the upper and lower sides of the through-wall steel sleeve (31) behind the steel pad (33) and the outer sides of the wall outer ribs (511) on the left and right sides of the through-wall steel sleeve (31); Continue construction until step nine is completed. Step d, after the formwork is removed, the prestressed anchor structure (3) is constructed. First, the hole of the through-wall steel sleeve (31) is cleaned, and the prestressed anchor structure (3) is drilled into the soil between the piles (7) through the through-wall steel sleeve (31). After the drilling is completed, the steel strand anchor (36) is inserted and grouting is performed to anchor it; Step e, after the age and strength of the grouting consolidation body meet the requirements, a wedge-shaped pressure plate (34) is installed, the steel strand anchor rod (36) is passed through the wedge-shaped pressure plate (34), and then an anchor (35) is installed to tension the steel strand anchor rod (36); Then in step nine, the cast-in-place concrete wall structure (2) is first cast to 0.7 m below the elevation of the prestressed anchor structure (3). After the construction of the prestressed anchor structure (3) is completed, the next section of earthwork is excavated and the process continues to step ten.

9. The construction method of combined support of pile rows and concrete walls according to claim 6 is characterized by: When the excavation trench is below the groundwater level and no prestressed anchor structure (3) is designed, In step 2, the excavation dimensions of the trench sections are as follows: First, excavate to 0.5m above the groundwater level, then use a telescopic arm grab bucket to excavate in sections. The excavation length is no more than 6m for each section. The excavation depth is no more than 2m. Add a dewatering step and dig a drainage well inside the foundation pit near the cast-in-place concrete wall structure (2). The construction steps for installing the wall reinforcement cage in step seven are as follows: Step f, firstly threading the inner wall reinforcement (512) to the top connection end of the current layer reinforcement connection sleeve (10), and then threading to the bottom connection end of the upper layer reinforcement connection sleeve (8); Step g, then fixing and connecting the outer wall reinforcement (511) and the double-layer horizontal ladder reinforcement (52) into a whole; Step h, lowering the double-layer horizontal ladder reinforcement (52) and the outer wall reinforcement (511) as a whole, and installing the outer reinforcement between the top connection end of the reinforcement connection sleeve (10) of the current layer and the bottom connection end of the reinforcement connection sleeve (8) at the upper stage.

10. The construction method of combined support of pile rows and concrete walls according to claim 6, characterized in that: When the excavation trench is below the groundwater level and a prestressed anchor structure (3) is designed, In step 2, the excavation dimensions of the trench sections are as follows: First, excavate to 0.5m above the groundwater level, then use a telescopic arm grab bucket to excavate in sections. The excavation length is no more than 6m for each section. The excavation depth is no more than 2m. Add a dewatering step and dig a drainage well inside the foundation pit near the cast-in-place concrete wall structure (2). The construction steps for installing the wall reinforcement cage in step seven are as follows: Step i, firstly, installing the inner wall reinforcement (512) between the top connection end of the current layer reinforcement connection sleeve (10) and the bottom connection end of the upper layer reinforcement connection sleeve (8); Step j, then the outer wall reinforcement (511) and the double-layer horizontal ladder reinforcement (52) are fixedly connected into a whole; Step k, the middle part of the barrel of the wall-penetrating steel sleeve (31) is fixedly connected to the double-layer horizontal ladder reinforcement by arranging two vertical connecting pieces, so that the wall-penetrating steel sleeve (31) is fixedly connected to the outer wall reinforcement (511) and the double-layer horizontal ladder reinforcement (52) into a whole; Step 1, welding a steel backing plate (33) on the front end surface of the wall-penetrating steel sleeve (31); Step m, fixing and connecting the horizontal structural reinforcement ribs (32) to the upper and lower sides of the front end of the through-wall steel sleeve (31) behind the steel pad (33) and the outer sides of the wall outer ribs (511) on the left and right sides of the through-wall steel sleeve (31); Step n, lowering the wall-penetrating steel sleeve (31), the outer wall reinforcement (511) and the double-layer horizontal ladder reinforcement (52) into the slot section as a whole, close to the inner wall reinforcement (512) during lowering, and after lowering to the designed elevation, fixing and connecting the inner wall reinforcement (512) and the upper ladder reinforcement (521); Continue construction until step nine is completed. Step p, after the formwork is removed, the prestressed anchor structure (3) is constructed. First, the hole of the through-wall steel sleeve (31) is cleaned, and the prestressed anchor structure (3) is drilled into the soil between the piles (7) through the through-wall steel sleeve (31). After the drilling is completed, the steel strand anchor (36) is inserted and grouting is performed to anchor it; Step q, after the age and strength of the grouting consolidation body meet the requirements, a wedge-shaped pressure plate (34) is installed, the steel strand anchor rod (36) is passed through the wedge-shaped pressure plate (34), and then an anchor (35) is installed to tension the steel strand anchor rod (36); Then in step nine, the cast-in-place concrete wall structure (2) is first cast to 0.7 m below the elevation of the prestressed anchor structure (3). After the construction of the prestressed anchor structure (3) is completed, the next section of earthwork is excavated and the process continues to step ten.

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