阅读说明：本技术 一种现役建筑浅基础后置组合桩加固结构及其施工方法 (Active-service building shallow-foundation postposition composite pile reinforcing structure and construction method thereof ) 是由 韩尚宇 杨辉 李连国 于 2021-08-26 设计创作，主要内容包括：本申请涉及一种现役建筑浅基础后置组合桩加固结构及其施工方法,它包括在浅基础外侧先挖设灌注桩桩孔,再钻设钢管桩桩孔,并在钢管桩桩孔内插设钢管桩；灌注桩与钢管桩的上部设置基础承台,并在钢管桩的上部设置桩芯钢筋笼、反压撑板和连接帽板；混凝土灌注施工时,先进行灌注桩混凝土灌注施工,并通过稳固锚定板及灌注桩混凝土自重控制钢管桩的位置；在浅基础附近框架梁的下表面设置应变计、结构柱的外侧设置反光标；在框架梁与建筑地面板之间设置补强撑柱,在开挖作业槽的外侧设置劲性支护体和坑外固化体。本发明可提升浅基础的承载能力,降低基础加固施工对现役建筑的影响,减小施工难度。(The application relates to a post-combined pile reinforcing structure of an active building shallow foundation and a construction method thereof, which comprises the steps of firstly digging a cast-in-place pile hole on the outer side of the shallow foundation, then drilling a steel pipe pile hole, and inserting a steel pipe pile in the steel pipe pile hole; arranging a foundation bearing platform on the upper parts of the cast-in-place pile and the steel pipe pile, and arranging a pile core reinforcement cage, a back pressure supporting plate and a connecting cap plate on the upper part of the steel pipe pile; during concrete pouring construction, firstly performing concrete pouring construction of a pouring pile, and controlling the position of the steel pipe pile through the self weight of the stable anchoring plate and the concrete of the pouring pile; the lower surface of a frame beam near a shallow foundation is provided with a strain gauge, and the outer side of a structural column is provided with a reflecting mark; and a reinforcing support column is arranged between the frame beam and the building floor slab, and a rigid support body and a pit outer curing body are arranged outside the excavation operation groove. The invention can improve the bearing capacity of the shallow foundation, reduce the influence of foundation reinforcement construction on the existing building and reduce the construction difficulty.)

1. A construction method of a post-combination pile reinforced structure of a shallow foundation of an active building is characterized by comprising the following steps:

step S1: construction preparation is carried out, sundries around a foundation reinforcement area are removed, and surveying is carried out around a shallow foundation of the building to be reinforced; determining the plane position of the steel pipe pile, and preparing materials and devices required by construction;

step S2: laying an active building safety monitoring system, sticking a reflective mark on the side wall of a structural column above a shallow foundation, sticking a strain gauge on the lower surface of a frame beam, arranging a reinforcing support column between a ground plate near the shallow foundation and the frame beam, welding a support column end plate at the joint of the reinforcing support column and the frame beam as well as the ground plate, and arranging a column top beam at the top end of the structural column;

step S3: excavating a foundation soil body retaining wall, firstly carrying out in-situ solidification on the foundation soil body outside the shallow foundation to form a solidified body outside the pit, and then inserting a stiff supporting body in the vertical direction along the side, facing the shallow foundation, of the solidified body outside the pit; excavating foundation soil between the shallow foundation and the stiff supporting body above the elevation of the top surface of the shallow foundation to form a construction pit slot, wherein the width of the construction pit slot is 1-3 m; a pit bottom pressing plate is arranged on the upper surface of the construction pit slot, and a pressing plate control body with adjustable length is arranged between the pit bottom pressing plate and the stiff support body;

step S4: processing the free surface of the shallow foundation, firstly adopting an air pick or an impact drill to carry out interface roughening on the upper surface of the shallow foundation, and then implanting interface connecting ribs into holes on the outer surface of the shallow foundation;

step S5: constructing a hole-digging cast-in-place pile, respectively digging cast-in-place pile holes with the depth of 2-4 m at two sides of a shallow foundation, and arranging cast-in-place pile retaining walls on the inner side walls of the cast-in-place pile holes along the direction of the cast-in-place pile to form the cast-in-place pile; the length of the cast-in-place pile retaining wall is consistent with that of the cast-in-place pile;

step S6: inserting a steel pipe pile guide hole, arranging a column side connecting rib at the bottom of the structural column, and arranging a supporting lug plate with an L-shaped cross section on the outer side wall of the column side connecting rib; arranging a construction platform plate on the upper surfaces of the supporting lug plates and the ground plate or the foundation soil body, arranging a hole guiding drilling machine on the construction platform plate, and drilling a tubular pile drilling hole by adopting a hole guiding drill bit of the hole guiding drilling machine; sleeving a support disc sleeve on the outer walls of the tubular pile insertion pipe and the rear grouting pipe, connecting the tubular pile insertion pipe and the rear grouting pipe into a whole by adopting a support disc connecting rib in advance, synchronously inserting the tubular pile insertion pipe and the rear grouting pipe into a pipe cavity of a cast-in-place pile retaining wall, and firmly connecting the rear grouting pipe and the cast-in-place pile retaining wall through a support disc control body and a retaining wall pressing plate;

step S7: grouting the pile hole combination, arranging a back pressure supporting plate at the top of the steel pipe pile, and arranging a stable anchor rib on the back pressure supporting plate, so that a stable anchoring plate at the bottom end of the stable anchor rib is positioned at the bottom of the construction pit slot; arranging a pile core reinforcement cage at the top of the steel pipe pile, and binding the pile core reinforcement cage and the bearing platform reinforcement cage into a whole; firstly, carrying out concrete pouring construction on a poured pile through concrete pouring equipment outside the steel pipe pile, and then grouting into a pipe cavity of the steel pipe pile through a rear grouting pipe to form a pile core reinforcement;

step S8: pouring a foundation bearing platform, removing a construction platform plate, and welding a cap plate at the top end of the pile core steel reinforcement cage; and pouring concrete on the peripheries of the cast-in-place piles and the steel pipe piles to form a foundation bearing platform.

2. The construction method of the active building shallow foundation post-combination pile reinforced structure according to claim 1, wherein the pit bottom pressing plate in the step S3 is formed by rolling a steel plate and is connected with the pressing plate position control body by welding; the pressing plate position control body comprises a bolt and screws, and the fastening directions of the screws on two sides of the bolt are opposite.

3. The construction method of the active building shallow foundation post-composite pile reinforced structure according to claim 1, wherein the interface connection bar in the step S4 is made of a twisted steel bar or a stainless steel pipe, and is bonded with the shallow foundation by concrete pouring.

4. A post-combined pile reinforcing structure of an active building shallow foundation is characterized by comprising a shallow foundation, an interface connecting rib, a structural column, a reflecting mark, a frame beam, a column top beam, a strain gauge, a reinforcing support column, a ground panel, a counter-force support assembly and an anchoring assembly; the shallow foundation part is embedded into a foundation soil body, the side surface of the shallow foundation is provided with an interface connecting rib, and the surface of the foundation soil body is provided with a ground panel; one end of the structural column is connected with the shallow foundation, the other end of the structural column is connected with the column top cross beam, and a reflective mark is arranged on the structural column; the frame beam is arranged on the column top beam, the frame beam is provided with a strain gauge, one end of the reinforcing support column is connected with the frame beam, and the other end of the reinforcing support column is connected with the ground panel; the counter-force supporting assembly is arranged at one end of the structural column connected with the shallow foundation, one end of the anchoring assembly is connected with the counter-force supporting assembly, and the other end of the anchoring assembly is connected with the foundation soil body;

the counter-force supporting assembly comprises an outer pit solidifying body, a column side connecting rib, a supporting lug plate, a bearing platform reinforcement cage and a foundation bearing platform, wherein the outer pit solidifying body is arranged around the periphery of the shallow foundation; one end of the structural column connected with the shallow foundation is provided with a column side connecting rib; the outer side wall of the column side connecting rib is provided with a supporting lug plate with an L-shaped cross section; a foundation bearing platform is arranged between the pit outer solidifying body and the shallow foundation, and a bearing platform steel reinforcement cage is arranged in the foundation bearing platform;

the anchoring assembly comprises a steel pipe pile, a back pressure supporting plate, a cast-in-place pile, a stable anchor rib, a stable anchoring plate, a pile core reinforcement cage and a connecting cap plate; one end of the cast-in-place pile is connected with the foundation bearing platform, and the other end of the cast-in-place pile is connected with the foundation soil body; the cast-in-place pile comprises a cast-in-place pile hole and a cast-in-place pile retaining wall, wherein a tubular pile inserting pipe, a rear grouting pipe, a retaining wall pressing plate, a supporting disc sleeve pipe, a supporting disc connecting rib and a supporting disc control body are arranged in the cast-in-place pile hole;

the steel pipe pile is arranged in the pipe pile insertion pipe and penetrates through the pipe pile insertion pipe; one end of the steel pipe pile is inserted into the foundation bearing platform, and the other end of the steel pipe pile is inserted into the foundation soil body; the steel-pipe pile with the one end that basic cushion cap is connected is provided with back pressure fagging and stake core steel reinforcement cage, be provided with firm anchor bar on the back pressure fagging, firm anchor bar bottom is provided with firm anchor plate, stake core steel reinforcement cage with the cushion cap steel reinforcement cage is connected, be provided with the connection cap board on the stake core steel reinforcement cage.

5. The active building shallow foundation post-composite pile reinforcing structure as claimed in claim 4, wherein the steel pipe pile is provided with a slurry seepage hole, and a pile core reinforcement is arranged inside the steel pipe pile.

6. The active building shallow foundation post-composite pile reinforcing structure as claimed in claim 4, wherein the strain gauge adopts a concrete surface strain gauge or a steel plate gauge; the reflective cursors are cross reflective cursors and are arranged along the structural column at even vertical intervals, and the number of the reflective cursors is 2-3.

7. The active building shallow foundation post-composite pile reinforcement structure as claimed in claim 4, wherein the cured body outside the pit is cement paste, hydrated lime or microorganism slurry.

8. The active building shallow foundation post-combination pile reinforcing structure as claimed in claim 4, wherein the internal diameter of the supporting disk sleeve is 1.1-1.3 times of the external diameter of a post-grouting pipe or a pipe pile inserting pipe, and the supporting disk sleeve is welded with the supporting disk connecting rib; the supporting disc position control body comprises a bolt and screws, the fastening directions of the screws on the two sides of the bolt are opposite, and the screws on the two sides of the bolt are respectively connected with the supporting disc sleeve and the retaining wall pressing plate in a welding mode; the retaining wall pressing plate is formed by rolling a steel plate, the cross section of the retaining wall pressing plate is arc-shaped, and the outer diameter of the retaining wall pressing plate is the same as the inner diameter of the retaining wall of the cast-in-place pile.

9. The active building shallow foundation post-composite pile reinforcing structure as claimed in claim 4, wherein the connecting cap plate is welded into a grid shape by steel plate strips or steel bars, and the cross section is in a circular basin shape.

10. The active building shallow foundation post-composite pile reinforcing structure as claimed in claim 4, wherein one end of the reinforcing brace connected with the ground panel is provided with a brace end plate.

Technical Field

The application relates to the technical field of shallow foundation reinforcement, in particular to a post-combined pile reinforced structure of an existing-service building shallow foundation and a construction method thereof.

Background

In order to improve the bearing capacity of the shallow foundation of the existing building and improve the function and safety of the existing building, the building foundation is often reinforced. The foundation is used as a building foundation structure form which is relatively common in application, and the improvement of the bearing capacity of the foundation is always important content of building reinforcement. When the shallow foundation of building is consolidated, often need to solve bearing capacity promotion, existing building protection scheduling technical problem.

The prior art has a shallow foundation building reinforcing structure, which comprises a pile cap, an anchor rod static pressure pile, a pile sealing plate and a filling layer, wherein the pile cap is an original building shallow foundation after deviation correction of a building or an additional foundation part is additionally arranged on the original building shallow foundation, a pile pressing hole is formed in the upper surface of the pile cap, the static pressure pile is positioned in the pile pressing hole, the pile top of the static pressure pile is positioned in the pile pressing hole, the pile pressing hole is positioned in the hole section of the original building shallow foundation or the pile cap, concrete is poured in the pile pressing hole, the pile top of the anchor rod static pressure pile is provided with an anchor bar, and the anchor bar is anchored in the concrete in the pile pressing hole; the pile-pressing anchor rod penetrates into the pile-pressing anchor rod from the upper surface of the bearing platform and is positioned around the periphery of the pile-pressing hole, the upper end of the pile-pressing anchor rod is exposed out of the upper surface of the pile bearing platform, and the pile-pressing anchor rod is sealed in the pile-pressing hole through pouring concrete to form a pile sealing plate. Although the construction method can realize pile foundation reinforcement of shallow foundation, the structure can not realize combined reinforcement of the steel pipe pile and the cast-in-place pile, the existing building is difficult to be protected synchronously, and the improvement and the integral reinforcement of the foundation bearing performance are limited.

Disclosure of Invention

The invention aims to provide a post-combination pile reinforcing structure of an active building shallow foundation and a construction method thereof, which effectively reduce the field construction difficulty of the post-combination pile reinforcing structure of the active building shallow foundation, improve the bearing capacity of the shallow foundation and reduce the influence of foundation reinforcing construction on the active building.

The invention adopts a technical scheme that: a construction method of a post-combination pile reinforced structure of an active building shallow foundation comprises the following steps:

step S1: and (5) carrying out construction preparation, removing sundries around the foundation reinforcement area, and surveying around the shallow foundation of the building to be reinforced. Determining the plane position of the steel pipe pile, and preparing materials and devices required by construction;

step S2: laying an active building safety monitoring system, sticking a reflective mark on the side wall of a structural column above a shallow foundation, sticking a strain gauge on the lower surface of a frame beam, arranging a reinforcing support column between a ground plate near the shallow foundation and the frame beam, welding a support column end plate at the joint of the reinforcing support column and the frame beam as well as the ground plate, and arranging a column top beam at the top end of the structural column;

step S3: excavating a foundation soil body retaining wall, firstly carrying out in-situ solidification on the foundation soil body outside the shallow foundation to form a solidified body outside the pit, and then inserting a stiff supporting body in the vertical direction along the side, facing the shallow foundation, of the solidified body outside the pit; excavating foundation soil between the shallow foundation and the stiff supporting body above the elevation of the top surface of the shallow foundation to form a construction pit slot, wherein the width of the construction pit slot is 1-3 m; a pit bottom pressing plate is arranged on the upper surface of the construction pit slot, and a pressing plate control body with adjustable length is arranged between the pit bottom pressing plate and the stiff support body;

step S4: processing the free surface of the shallow foundation, firstly adopting an air pick or an impact drill to carry out interface roughening on the upper surface of the shallow foundation, and then implanting interface connecting ribs into holes on the outer surface of the shallow foundation;

step S5: constructing a hole-digging cast-in-place pile, respectively digging cast-in-place pile holes with the depth of 2-4 m at two sides of a shallow foundation, and arranging cast-in-place pile retaining walls on the inner side walls of the cast-in-place pile holes along the direction of the cast-in-place pile to form the cast-in-place pile; the length of the cast-in-place pile retaining wall is consistent with that of the cast-in-place pile;

step S6: inserting a steel pipe pile guide hole, arranging a column side connecting rib at the bottom of the structural column, and arranging a supporting lug plate with an L-shaped cross section on the outer side wall of the column side connecting rib; arranging a construction platform plate on the upper surfaces of the supporting lug plates and the ground plate or the foundation soil body, arranging a hole guiding drilling machine on the construction platform plate, and drilling a tubular pile drilling hole by adopting a hole guiding drill bit of the hole guiding drilling machine; sleeving a support disc sleeve on the outer walls of the tubular pile insertion pipe and the rear grouting pipe, connecting the tubular pile insertion pipe and the rear grouting pipe into a whole by adopting a support disc connecting rib in advance, synchronously inserting the tubular pile insertion pipe and the rear grouting pipe into a pipe cavity of a cast-in-place pile retaining wall, and firmly connecting the rear grouting pipe and the cast-in-place pile retaining wall through a support disc control body and a retaining wall pressing plate;

step S7: grouting the pile hole combination, arranging a back pressure supporting plate at the top of the steel pipe pile, and arranging a stable anchor rib on the back pressure supporting plate, so that a stable anchoring plate at the bottom end of the stable anchor rib is positioned at the bottom of the construction pit slot; arranging a pile core reinforcement cage at the top of the steel pipe pile, and binding the pile core reinforcement cage and the bearing platform reinforcement cage into a whole; firstly, carrying out concrete pouring construction on a poured pile through concrete pouring equipment outside the steel pipe pile, and then grouting into a pipe cavity of the steel pipe pile through a rear grouting pipe to form a pile core reinforcement;

step S8: pouring a foundation bearing platform, removing a construction platform plate, and welding a cap plate at the top end of the pile core steel reinforcement cage; and pouring concrete on the peripheries of the cast-in-place piles and the steel pipe piles to form a foundation bearing platform.

Further, the pit bottom pressing plate in the step S3 is formed by rolling a steel plate and is connected with the pressing plate position control body in a welding manner; the pressing plate position control body comprises a bolt and screws, and the fastening directions of the screws on two sides of the bolt are opposite.

Further, the interface connection rib in the step S4 is made of a thread steel bar or a stainless steel pipe, and is bonded with the shallow foundation through concrete glue injection.

The other technical scheme adopted by the invention is as follows: a post-combined pile reinforcing structure for a shallow foundation of an active building comprises the shallow foundation, an interface connecting rib, a structural column, a reflecting mark, a frame beam, a column top beam, a strain gauge, a reinforcing support column, a ground panel, a reflecting support assembly and an anchoring assembly; the shallow foundation part is embedded into a foundation soil body, the side surface of the shallow foundation is provided with an interface connecting rib, and the surface of the foundation soil body is provided with a ground panel; one end of the structural column is connected with the shallow foundation, the other end of the structural column is connected with the column top cross beam, and a reflective mark is arranged on the structural column; the frame beam is arranged on the column top beam, the frame beam is provided with a strain gauge, one end of the reinforcing support column is connected with the frame beam, and the other end of the reinforcing support column is connected with the ground panel; the counter-force supporting assembly is arranged at one end of the structural column connected with the shallow foundation, one end of the anchoring assembly is connected with the counter-force supporting assembly, and the other end of the anchoring assembly is connected with the foundation soil body;

the counter-force supporting assembly comprises an outer pit solidifying body, a column side connecting rib, a supporting lug plate, a bearing platform reinforcement cage and a foundation bearing platform, wherein the outer pit solidifying body is arranged around the periphery of the shallow foundation; one end of the structural column connected with the shallow foundation is provided with a column side connecting rib; the outer side wall of the column side connecting rib is provided with a supporting lug plate with an L-shaped cross section; a foundation bearing platform is arranged between the pit outer solidifying body and the shallow foundation, and a bearing platform steel reinforcement cage is arranged in the foundation bearing platform;

the anchoring assembly comprises a steel pipe pile, a back pressure supporting plate, a cast-in-place pile, a stable anchor rib, a stable anchoring plate, a pile core reinforcement cage and a connecting cap plate; one end of the cast-in-place pile is connected with the foundation bearing platform, and the other end of the cast-in-place pile is connected with the foundation soil body; the cast-in-place pile comprises a cast-in-place pile hole and a cast-in-place pile retaining wall, wherein a tubular pile inserting pipe, a rear grouting pipe, a retaining wall pressing plate, a supporting disc sleeve pipe, a supporting disc connecting rib and a supporting disc control body are arranged in the cast-in-place pile hole;

the steel pipe pile is arranged in the pipe pile insertion pipe and penetrates through the pipe pile insertion pipe; one end of the steel pipe pile is inserted into the foundation bearing platform, and the other end of the steel pipe pile is inserted into the foundation soil body; the steel-pipe pile with the one end that basic cushion cap is connected is provided with back pressure fagging and stake core steel reinforcement cage, be provided with firm anchor bar on the back pressure fagging, firm anchor bar bottom is provided with firm anchor plate, stake core steel reinforcement cage with the cushion cap steel reinforcement cage is connected, be provided with the connection cap board on the stake core steel reinforcement cage.

Furthermore, the steel pipe pile is provided with a slurry seepage hole, and a pile core reinforcement body is arranged inside the steel pipe pile.

Further, the strain gauge adopts a concrete surface strain gauge or a steel plate meter; the reflective cursors are cross reflective cursors and are arranged along the structural column at even vertical intervals, and the number of the reflective cursors is 2-3.

Further, the solidified body outside the pit is cement paste, hydrated lime or microorganism slurry.

Furthermore, the inner diameter of the supporting disk sleeve is 1.1-1.3 times of the outer diameter of a rear grouting pipe or a pipe pile inserting pipe, and the supporting disk sleeve is welded with the supporting disk connecting rib; the supporting disc position control body comprises a bolt and screws, the fastening directions of the screws on the two sides of the bolt are opposite, and the screws on the two sides of the bolt are respectively connected with the supporting disc sleeve and the retaining wall pressing plate in a welding mode; the retaining wall pressing plate is formed by rolling a steel plate, the cross section of the retaining wall pressing plate is arc-shaped, and the outer diameter of the retaining wall pressing plate is the same as the inner diameter of the retaining wall of the cast-in-place pile.

Furthermore, the connecting cap plate is welded into a grid shape by adopting steel plate strips or steel bars, and the cross section of the connecting cap plate is in a circular basin shape.

Furthermore, one end of the reinforcing support column connected with the ground panel is provided with a support column end plate.

The invention has the beneficial effects that:

(1) firstly digging a cast-in-place pile hole on the outer side of a shallow foundation, then drilling a steel pipe pile hole, and inserting a steel pipe pile into the steel pipe pile hole; the upper parts of the cast-in-place pile and the steel pipe pile are provided with a foundation bearing platform, and the top of the steel pipe pile is provided with a pile core reinforcement cage, a back pressure supporting plate and a connecting cap plate, so that the integrity of the steel pipe pile, the foundation bearing platform and the cast-in-place pile can be further enhanced.

(2) When the invention is used for concrete pouring construction, the pouring construction of the pouring pile concrete is firstly carried out, and the position of the steel pipe pile is controlled by the self weight of the stable anchoring plate and the pouring pile concrete, thereby solving the problem that the steel pipe pile floats upwards in the concrete pouring process.

(3) The strain gauge is arranged on the lower surface of the frame beam near the shallow foundation, and the reflective mark is arranged on the outer side of the structural column, so that the stress and deformation of a component can be synchronously monitored in the shallow foundation reinforcement construction process; meanwhile, the reinforcing support columns are arranged between the frame beams and the building floor plate, so that the influence of site construction on the existing building components can be effectively reduced; the stiffness supporting body and the pit outer solidifying body are arranged on the outer side of the excavation operation groove, so that the stability of a foundation soil body in the construction process is improved.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art that other drawings can be obtained according to these drawings without creative efforts.

FIG. 1 is a flow chart of a construction method according to an embodiment of the present invention;

FIG. 2 is a schematic diagram of a construction state at step S2 according to the embodiment of the present invention;

FIG. 3 is a schematic diagram of the construction status at step S4 according to the embodiment of the present invention;

FIG. 4 is a schematic view illustrating a construction state at step S6 according to the embodiment of the present invention;

FIG. 5 is a schematic diagram b illustrating the construction status at step S6 according to the embodiment of the present invention;

FIG. 6 is a schematic structural view of the completed construction of the embodiment of the present invention;

FIG. 7 is a schematic structural diagram of a steel pipe pile according to an embodiment of the present invention;

FIG. 8 is a side cross-sectional view of a cast-in-place pile according to an embodiment of the invention;

FIG. 9 is a cross-sectional view of a cast-in-place pile according to an embodiment of the present invention;

FIG. 10 is an enlarged view of a portion A of FIG. 4;

FIG. 11 is a partial enlarged view of portion B of FIG. 5;

fig. 12 is a partially enlarged view of a portion C in fig. 6.

The reference signs explain: 1-shallow foundation, 2-steel pipe pile, 3-structural column, 4-frame beam, 5-reflecting mark, 6-strain gauge, 7-reinforcing support column, 8-ground plate, 9-support column end plate, 10-column top beam, 11-foundation soil body, 12-pit external solidified body, 13-stiff supporting body, 14-construction pit groove, 15-pit bottom pressing plate, 16-pressing plate control body, 17-interface connecting rib, 18-filling pile hole, 19-filling pile protection wall, 20-column side connecting rib, 21-supporting lug plate, 22-construction platform plate, 23-lead hole drilling machine, 24-lead hole drill bit, 27-pipe pile inserting pipe, 28-post-filling pipe, 29-protection wall pressing plate, 30-slurry seepage hole, 31-supporting disk sleeve, 32-supporting disk connecting ribs, 33-supporting disk control bodies, 34-counter pressure supporting plates, 35-stabilizing anchor ribs, 36-stabilizing anchor plates, 37-pile core reinforcement cages, 38-bearing platform reinforcement cages, 39-cast-in-place piles, 40-pile core reinforcements, 42-connecting cap plates and 43-foundation bearing platforms.

Detailed Description

In order that the above objects, features and advantages of the present invention can be more clearly understood, a more particular description of the invention will be rendered by reference to the appended drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, however, the present invention may be practiced in other ways than those specifically described herein, and thus the present invention is not limited to the specific embodiments disclosed below.

Unless defined otherwise, technical or scientific terms used herein shall have the ordinary meaning as understood by one of ordinary skill in the art to which this application belongs. The use of "first," "second," and similar terms in the description and claims of this patent application do not denote any order, quantity, or importance, but rather the terms are used to distinguish one element from another. Also, the use of the terms "a" or "an" and the like do not denote a limitation of quantity, but rather denote the presence of at least one. The terms "connected" or "coupled" and the like are not restricted to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "upper", "lower", "left", "right", and the like are used merely to indicate relative positional relationships, and when the absolute position of the object being described is changed, the relative positional relationships are changed accordingly.

As shown in fig. 1, the embodiment of the invention adopts a construction method of a post-composite pile reinforced structure of an active building shallow foundation 1, which comprises the following steps:

step S1: and (5) carrying out construction preparation, removing sundries around the foundation reinforcement area, and surveying around the shallow foundation 1 of the building to be reinforced. And determining the plane position of the steel pipe pile 2, and preparing materials and devices required by construction.

Step S2: laying an active building safety monitoring system, pasting a reflective mark 5 on the side wall of a structural column 3 above a shallow foundation 1, pasting a strain gauge 6 on the lower surface of a frame beam 4, arranging a reinforcing brace 7 between a ground plate 8 near the shallow foundation 1 and the frame beam 4, welding a brace end plate 9 at the joint of the reinforcing brace 7, the frame beam 4 and the ground plate 8, and arranging a column top beam 10 at the top end of the structural column 3.

Step S3: excavating a foundation soil body 11 retaining block, firstly carrying out in-situ solidification on the foundation soil body 11 outside the shallow foundation 1 to form an outside-pit solidified body 12, and then inserting a stiff supporting body 13 in the vertical direction on the side, facing the shallow foundation 1, of the outside-pit solidified body 12; excavating foundation soil between the shallow foundation 1 and the stiff supporting body 13 above the top surface elevation of the shallow foundation 1 to form a construction pit slot 14, wherein the width of the construction pit slot 14 is 1-3 m; a pit bottom pressing plate 15 is arranged on the upper surface of the construction pit slot 14, and a pressing plate control body 16 with adjustable length is arranged between the pit bottom pressing plate 15 and the stiff support body 13; the pit bottom pressing plate 15 is formed by rolling a steel plate and is connected with the pressing plate control body 16 in a welding mode; the pressing plate control body 16 comprises a bolt and a screw rod, and the fastening directions of the screw rods on the two sides of the bolt are opposite.

Step S4: processing the free surface of the shallow foundation 1, firstly adopting an air pick or an impact drill to perform interface roughening on the upper surface of the shallow foundation 1, and then introducing holes in the outer surface of the shallow foundation 1 and implanting interface connecting ribs 17; the interface connecting rib 17 is made of a threaded steel bar or a stainless steel pipe and is bonded with the shallow foundation 1 through concrete glue injection.

Step S5: constructing a hole-digging cast-in-place pile 39, digging cast-in-place pile holes 18 with the depth of 2-4 m on two sides of the shallow foundation 1 respectively, and arranging cast-in-place pile retaining walls 19 on the inner side walls of the cast-in-place pile holes 18 along the direction of the cast-in-place pile 39 to form the cast-in-place pile 39; the length of the cast-in-place pile retaining wall 19 corresponds to the length of the cast-in-place pile 39.

Step S6: inserting a guide hole of the steel pipe pile 2, arranging a column side connecting rib 20 at the bottom of the structural column 3, and arranging a supporting lug plate 21 with an L-shaped cross section on the outer side wall of the column side connecting rib 20; arranging a construction platform plate 22 on the upper surfaces of the supporting ear plates 21 and the ground plate 8 or the foundation soil body 11, arranging a hole guiding drilling machine 23 on the construction platform plate 22, and drilling a tubular pile drilling hole by adopting a hole guiding drill bit 24 of the hole guiding drilling machine 23; the supporting disc sleeve 31 is sleeved on the outer walls of the tubular pile inserting pipe 27 and the rear grouting pipe 28, the tubular pile inserting pipe 27 and the rear grouting pipe 28 are connected into a whole in advance by the supporting disc connecting rib 32, the tubular pile inserting pipe 27 and the rear grouting pipe 28 are synchronously inserted into the pipe cavity of the cast-in-place pile protecting wall 19, and the rear grouting pipe 28 and the cast-in-place pile protecting wall 19 are firmly connected through the supporting disc control body 33 and the protecting wall pressing plate 29.

Step S7: grouting the pile hole combination, arranging a back pressure support plate 34 at the top of the steel pipe pile 2, and arranging a stable anchor bar 35 on the back pressure support plate 34, so that a stable anchor plate 36 at the bottom end of the stable anchor bar 35 is positioned at the bottom of the construction pit 14; arranging a pile core reinforcement cage 37 at the top of the steel pipe pile 2, and binding the pile core reinforcement cage 37 and a bearing platform reinforcement cage 38 into a whole; the concrete pouring construction of the cast-in-place pile 39 is performed through concrete pouring equipment outside the steel pipe pile 2, and then the pile core reinforcement 40 is formed by grouting the pipe cavity of the steel pipe pile 2 through the rear grouting pipe 28.

Step S8: pouring a foundation bearing platform 43, removing the construction platform plate 22, and welding a connecting cap plate 42 at the top end of the pile core reinforcement cage 37; concrete is poured around the cast-in-place pile 39 and the steel pipe pile 2 to form a foundation bed 43.

In the embodiment of the invention, the shallow foundation 1 is a strip foundation with the burial depth of 1m and the bottom width of 1m, and the concrete strength grade is C30. The steel pipe pile 2 is formed by rolling a steel pipe with the diameter of 220mm, and slurry seepage holes 30 are preset in the outer side wall of the steel pipe pile 2; the slurry seepage hole 30 is 30mm in length and 10mm in width. The structural column 3 is a reinforced concrete column with the cross section size of 300mm multiplied by 300mm, and the concrete strength grade is C35. The frame beam 4 and the column top beam 10 are both reinforced concrete beams with the cross section dimension of 250mm multiplied by 400mm, and the concrete strength grade is C35. The reflective marker 5 adopts a cross reflective marker 5, 2 reflective markers are vertically arranged along the structural column 3 at intervals of 2 m. And the strain gauge 6 is a vibrating wire type concrete surface strain gauge 6. The reinforcing support column 7 is formed by rolling a steel pipe with the diameter of 100 mm. The floor board 8 is a concrete floor, the concrete strength grade is C30, and the thickness is 100 mm. The support column end plate 9 is formed by rolling a steel plate with the thickness of 10 mm. The foundation soil 11 is cohesive soil in a plastic state. The pit outer solidified body 12 is solidified by cement paste, and the cement is 32.5 ordinary portland cement. The stiff supporting body 13 is a wire-drawing steel sheet pile with the length of 1.5 m. The width of the construction pit 14 is 1.5m, and the depth is 0.8 m. The pit bottom pressing plate 15 is formed by rolling a steel plate with the thickness of 10mm and is connected with the pressing plate control body 16 in a welding mode; the pressing plate control body 16 comprises a screw rod and a bolt with the diameter of 60mm, and the fastening directions of the screw rods on the two sides of the bolt are opposite. The interface connection rib 17 is a threaded steel bar with the diameter of 25mm, and is bonded with the shallow foundation 1 through concrete injection.

Digging bored concrete pile holes 18 with the depth of 3m at two sides of the shallow foundation 1 respectively, and arranging bored concrete pile retaining walls 19 on the inner side walls of the bored concrete pile holes 18 along the direction of a bored concrete pile 39 to form bored concrete piles 39; the cast-in-place pile retaining wall 19 is prefabricated by adopting reinforced concrete materials, the outer diameter is 1000mm, and the concrete strength grade of the cast-in-place pile 39 is C30. The length of the cast-in-place pile retaining wall 19 corresponds to the length of the cast-in-place pile 39. The column side connecting rib 20 is formed by rolling a steel plate with the thickness of 10mm, the inner section is formed to be the same as that of the structural column 3, and the column side connecting rib 20 and the structural column 3 are firmly connected through a stud. The supporting ear plate 21 is formed by cutting a steel plate with the thickness of 10mm, the cross section of the supporting ear plate is L-shaped, and the supporting ear plate is connected with the column side connecting rib 20 in a welding mode. The construction platform plate 22 is formed by rolling a steel plate with the thickness of 6 mm. The hole guiding drilling machine 23 is a small spiral drilling machine, the diameter of a guide hole is 250mm, the hole guiding drilling bit 24 is an alloy drilling bit, and the hole diameter of a hole drilled by the tubular pile is 250 mm.

The supporting disk sleeve 31 is formed by rolling a steel pipe and has two specifications of 90mm inner diameter and 250mm inner diameter, a rear grouting pipe 28 is arranged in the supporting disk sleeve 31 with the inner diameter of 90mm, and a pipe pile inserting pipe 27 is arranged in the supporting disk sleeve 31 with the inner diameter of 250 mm; the inner diameter of the tubular pile inserting pipe 27 is 230mm, and the diameter of the rear grouting pipe 28 is 50 mm; the branch disk connecting rib 32 is formed by rolling a steel plate with the thickness of 10 mm. The retaining wall pressing plate 29 is formed by rolling a steel plate with the thickness of 3mm, the cross section of the retaining wall pressing plate is arc-shaped, and the outer diameter of the retaining wall pressing plate is the same as the inner diameter of the retaining wall 19 of the cast-in-place pile. The branch disc control body 33 comprises a bolt and a screw rod with the diameter of 30mm, and the fastening directions of the screw rods on the two sides of the bolt are opposite. The back pressure supporting plate 34 is formed by rolling a steel plate with the thickness of 10mm, and holes for the stable anchor bars 35 to penetrate through are preset in the back pressure supporting plate 34. The stable anchor bars 35 are screws with the diameter of 30 mm. The stable anchor plate 36 is formed by rolling a steel plate with the diameter of 10mm and is vertically welded and connected with the stable anchor bar 35. The pile core reinforcement cage 37 and the bearing platform reinforcement cage 38 are formed by binding threaded reinforcements with the diameters of 25mm and 10 mm. The pile core reinforcement 40 is made of fine-grained concrete with the strength grade of C35. The connecting cap plate 42 is formed by rolling a steel plate with the thickness of 10mm, the width of the connecting cap plate is 20cm, the vertical face of the connecting cap plate is in a round basin shape, and the diameter of the connecting cap plate is 1200 mm. The foundation cap 43 is formed by pouring concrete with the strength grade of C35, and the height is 900 mm.

In the embodiment of the invention, a cast-in-place pile hole 18 is firstly dug at the outer side of a shallow foundation 1, then a pile hole 2 of the steel pipe pile is drilled, and the steel pipe pile 2 is inserted in the pile hole 2 of the steel pipe pile; the cast-in-place pile 39 and the upper part of the steel pipe pile 2 are provided with a foundation bearing platform 43, and the top of the steel pipe pile 2 is provided with a pile core reinforcement cage 37, a back pressure supporting plate 34 and a connecting cap plate 42, so that the integrity of the steel pipe pile 2, the foundation bearing platform 43 and the cast-in-place pile 39 can be further enhanced. During concrete pouring construction, pouring construction of concrete of the pouring pile 39 is firstly carried out, the position of the steel pipe pile 2 is controlled through the self weight of the stable anchoring plate 36 and the concrete of the pouring pile 39, and the problem that the steel pipe pile 2 floats upwards in the concrete pouring process is solved. In the embodiment of the invention, the strain gauge 6 is arranged on the lower surface of the frame beam 4 near the shallow foundation 1, and the reflective mark 5 is arranged on the outer side of the structural column 3, so that the stress and deformation of a component can be synchronously monitored in the reinforcing construction process of the shallow foundation 1; meanwhile, the reinforcing support columns 7 are arranged between the frame beams 4 and the building floor plate 8, so that the influence of field construction on the existing building components can be effectively reduced; the stiffness supporting body 13 and the pit outer solidifying body 12 are arranged on the outer side of the excavation operation groove, so that the stability of the foundation soil body 11 in the construction process is improved.

As shown in fig. 2 to 12, the active building shallow foundation post-fabricated composite pile reinforcing structure can be obtained according to the steps, and comprises a shallow foundation 1, an interface connecting rib 17, a structural column 3, a reflective mark 5, a frame beam 4, a column top beam 10, a strain gauge 6, a reinforcing support column 7, a ground panel 8, a reactive force support component and an anchoring component; the shallow foundation 1 is partially embedded into a foundation soil body 11, an interface connecting rib 17 is arranged on the side surface of the shallow foundation 1, and a ground panel 8 is arranged on the surface of the foundation soil body 11; one end of the structural column 3 is connected with the shallow foundation 1, the other end of the structural column is connected with the column top beam 10, and a reflective mark 5 is arranged on the structural column 3; the frame beam 4 is arranged on the column top beam 10, and the frame beam 4 is provided with a strain gauge 6; the reflecting rod 5 and the strain gauge 6 can synchronously monitor the stress and deformation of the component during the reinforcing construction process of the shallow foundation 1. The strain gauge 6 can adopt a concrete surface strain gauge 6 or a steel plate gauge; the reflective marks 5 are cross reflective marks 5 and are arranged along the structural column 3 at even vertical intervals, and the number of the reflective marks 5 is 2-3. One end of the reinforcing support column 7 is connected with the frame beam 4, and the other end of the reinforcing support column is connected with the floor panel 8; one end of the reinforcing support column 7 connected with the ground panel 8 is also provided with a support column end plate 9 for improving the connection strength; the reinforcing support column 7 can effectively reduce the influence of site operation on the existing building components. The counter-force supporting component is arranged at one end of the structural column 3 connected with the shallow foundation 1, one end of the anchoring component is connected with the counter-force supporting component, and the other end of the anchoring component is connected with the foundation soil body 11.

The counter force support assembly comprises an outer pit solidified body 12, a column side connecting rib 20, a support lug plate 21, a bearing platform reinforcement cage 38 and a foundation bearing platform 43, wherein the outer pit solidified body 12 is arranged around the periphery of the shallow foundation 1; a column side connecting rib 20 is arranged at one end of the structural column 3 connected with the shallow foundation 1; the outer side wall of the column side connecting rib 20 is provided with a supporting lug plate 21 with an L-shaped cross section; a foundation bearing platform 43 is arranged between the pit outer solidified body 12 and the shallow foundation 1, and a bearing platform steel reinforcement cage 38 is arranged in the foundation bearing platform 43; the pit outer solidified body 12 is cement paste, hydrated lime or microorganism slurry, and can effectively improve the stability of the foundation soil body 11 in the construction process.

The anchoring assembly comprises a steel pipe pile 2, a back pressure supporting plate 34, a cast-in-place pile 39, a stabilizing anchor bar 35, a stabilizing anchor plate 36, a pile core reinforcement cage 37 and a connecting cap plate 42; one end of the cast-in-place pile 39 is connected with the foundation bearing platform 43, and the other end is connected with the foundation soil body 11; the cast-in-place pile 39 comprises a cast-in-place pile hole 18 and a cast-in-place pile protection wall 19, a tubular pile inserting pipe 27, a rear grouting pipe 28, a protection wall pressing plate 29, a supporting disc sleeve pipe 31, a supporting disc connecting rib 32 and a supporting disc control body 33 are arranged in the cast-in-place pile hole 18, the tubular pile inserting pipe 27 is arranged in the center of the cast-in-place pile hole 18, the rear grouting pipe 28 surrounds the tubular pile inserting pipe 27, the supporting disc sleeve pipe 31 is arranged on the outer wall of the tubular pile inserting pipe 27 and the outer wall of the rear grouting pipe 28, the inner diameter of the supporting disc sleeve pipe 31 is 1.1-1.3 times of the outer diameter of the rear grouting pipe 28 or the tubular pile inserting pipe 27, the supporting disc sleeve pipe 31 on the outer wall of the tubular pile inserting pipe 27 and the outer wall of the rear grouting pipe 28 is connected through the supporting disc connecting rib 32, and the supporting disc sleeve pipe 31 is connected with the supporting disc connecting rib 32 in a welding manner; the cast-in-place pile protecting wall 19 is provided with a protecting wall pressing plate 29, the protecting wall pressing plate 29 is formed by rolling a steel plate, the cross section of the protecting wall pressing plate is in a circular arc shape, and the outer diameter of the protecting wall pressing plate is the same as the inner diameter of the cast-in-place pile protecting wall 19; a supporting disk control body 33 is arranged between the wall protection pressing plate 29 and the supporting disk sleeve 31 on the outer wall of the rear grouting pipe 28; the supporting disc control body 33 comprises a bolt and screws, the fastening directions of the screws on the two sides of the bolt are opposite, and the screws on the two sides of the bolt are respectively connected with the supporting disc sleeve 31 and the retaining wall pressing plate 29 in a welding mode. The rear grouting pipe 28 and the retaining wall pressing plate 29 can be stably connected through the branch disc control body 33.

The steel pipe pile 2 is arranged in the pipe pile inserting pipe 27 and penetrates through the pipe pile inserting pipe 27, a slurry seepage hole 30 is formed in the steel pipe pile 2, a pile core reinforcement body 40 is arranged inside the steel pipe pile 2, and the pile core reinforcement body 40 can reinforce the compressive strength of the steel pipe pile 2; one end of the steel pipe pile 2 is inserted into the foundation bearing platform 43, and the other end of the steel pipe pile is inserted into the foundation soil body 11; a back pressure support plate 34 and a pile core reinforcement cage 37 are arranged at one end of the steel pipe pile 2 connected with the foundation bearing platform 43, a stable anchor bar 35 is arranged on the back pressure support plate 34, a stable anchor plate 36 is arranged at the bottom end of the stable anchor bar 35, the pile core reinforcement cage 37 is connected with the bearing platform reinforcement cage 38, and a connecting cap plate 42 is arranged on the pile core reinforcement cage 37; the connecting cap plate 42 is welded into a grid shape by adopting steel plate strips or steel bars, and the cross section is in a circular basin shape. The cast-in-place pile 39 and a foundation bearing platform 43 arranged at the upper part of the steel pipe pile 2, a pile core reinforcement cage 37 arranged at the top of the steel pipe pile 2, a back pressure supporting plate 34 and a connecting cap plate 42 can further enhance the integrity of the steel pipe pile 2, the foundation bearing platform 43 and the cast-in-place pile 39.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.