A repair and reinforcement structure of a crack-damaged anti-slide pile and a construction method thereof

Abstract

The application discloses a kind of repair and reinforcement structure of crack damage anti-slide pile, including respectively with the center line symmetry of anti-slide pile tensile side arrangement I-shaped steel reinforcement structure and prestressed anchor reinforcement structure, I-shaped steel reinforcement structure includes the reinforcement hole and I-shaped steel in the anti-slide pile body and close to the reinforcing bar of anti-slide pile tensile side, I-shaped steel is implanted into reinforcement hole and its bottom end and top end respectively exceed pile body bottom crack and top crack, the long side direction of web of I-shaped steel is along the direction of anti-slide pile shearing direction and is laid, reinforcement hole is injected with cement slurry, prestressed anchor reinforcement structure includes the anchoring hole and anchor cable in the anti-slide pile body and close to the reinforcing bar of anti-slide pile tensile side, anchoring hole includes the free section anchor cable hole in upper and the anchoring section anchor cable hole in lower, free section anchor cable hole lower end exceeds pile body bottom crack, anchor cable is anchored in anchoring hole by anchoring grouting, anchor cable is sealed in anti-slide pile top after prestress is applied;The application also discloses a kind of repair and reinforcement structure construction method of crack damage anti-slide pile.

Description

TECHNICAL FIELD

[0001] The present application relates to anti-slide pile repair and reinforcement technology, in particular to a repair and reinforcement structure of a crack-damaged anti-slide pile and a construction method thereof, and further relates to a construction method of the repair and reinforcement structure of the crack-damaged anti-slide pile. BACKGROUND

[0002] An anti-slide pile is a kind of structure that is buried in a stable stratum, and transmits the sliding force of a landslide to the stable stratum by the mutual clamping action of the pile and the surrounding rock-soil body, so as to stabilize the landslide by the anchoring action and passive resistance of the stable stratum. In recent years, the anti-slide pile has been rapidly popularized and applied in China due to its strong anti-slide capacity, small construction disturbance, flexible pile arrangement, timely formation or enhancement of the anti-slide force of the landslide, and the use of the pile hole as a survey verification hole of the landslide, and the like. Common forms of the anti-slide pile include rectangular and circular anti-slide piles, as well as various structural forms derived from the anti-slide pile, such as the row frame type anti-slide pile, the chair type anti-slide pile, and the anti-slide key.

[0003] In actual application sites, affected by the construction environment, the quality of the pile body, and the change of the rock-soil stress field of the landslide, especially under the deterioration of external conditions such as earthquakes, underground water, or continuous heavy rainfall, when the sliding force of the landslide increases, some anti-slide piles may be damaged, such as cracking or even breaking of the pile body, which affects the stability of the landslide. In severe cases, the insufficient resistance to load may cause the landslide to destroy the support and reinforcement structure and lose stability, resulting in damage to the engineering structure and loss of life and property of the people. The reasons for the shear failure of the anti-slide pile include: ① The actual sliding force of the landslide in the landslide area is greater than the designed sliding force, so that the pile body bears a sliding force greater than its anti-slide bearing capacity, thereby causing shear failure, breakage, or collapse; ② During construction, due to segregation of concrete, non-continuous pouring, or temperature difference shrinkage, the pile body may have quality defects such as loose structure, cavities, or wrapped soil, which are prone to cracks and shear failure; ③ The anti-slide pile has a small cross-sectional size or insufficient stirrup configuration, which may result in insufficient shear strength of the anti-slide pile and shear failure, and insufficient tensile reinforcement on the tensile side, which may result in insufficient bending capacity of the anti-slide pile and breakage of the pile body.

[0004] The reinforcement methods for the damaged structure of concrete in the construction engineering include the section reinforcement method, the outer steel reinforcement method, the prestress reinforcement method, the method of changing the force transmission path of the structure, the external steel reinforcement method, etc. The anti-slide pile balances the landslide thrust by using the anchoring effect and passive resistance of the stable stratum, and the pile body is basically buried in the rock-soil body. The damage types are mainly shear and breakage. Obviously, the reinforcement methods in the construction engineering are not suitable for the repair of the anti-slide pile. At present, the repair and reinforcement methods for the anti-slide pile mainly include the prestressed anchor cable oblique reinforcement technology and the grouting reinforcement technology: (1) the prestressed anchor cable oblique reinforcement anti-slide pile technology. In the case that there is no large displacement at the pile head and the pile bottom, the anchor head is fixedly arranged in front of the pile, the prestressed anchor cable anchoring segment is obliquely punched into the bedrock, and then the overall stress capacity of the anti-slide pile and the rock-soil body behind the pile is enhanced. This method is more suitable for the reinforcement of the anti-slide pile with insufficient anti-slide capacity and overall tilting. For the sheared or broken pile body, the oblique inboard anchoring will cause the tensile load in the compression zone, and the excessive prestress may cause the secondary breakage of the cracked anti-slide pile; (2) the grouting reinforcement and reinforcement anti-slide pile technology. The hole is drilled to the crack position at the pile top, the high-pressure grouting is filled, the crack is closed after the grouting cementation and solidification, the steel corrosion is prevented, and the purpose of repairing the pile quality is achieved. However, the grouting penetration is greatly affected by the crack distribution and width, and the effect of the grouting adhesion reinforcement on the shear and compression capacity of the pile is very small. SUMMARY

[0005] Therefore, one of the purposes of the present application is to provide a repair and reinforcement structure of the cracked damage anti-slide pile, which can improve the integrity and shear and bending resistance of the cracked damage anti-slide pile. The second purpose of the present application is to provide a construction method of the repair and reinforcement structure of the cracked damage anti-slide pile, which has simple construction process.

[0006] One of the purposes of the present application is realized by the following technical scheme:

[0007] The application discloses a reinforcing structure for repairing a crack-damaged anti-slide pile, which comprises an I-shaped steel reinforcing structure and a prestressed anchor cable reinforcing structure.

[0008] Further, the I-shaped steel is vertically fixed with end bearing plates at both ends, and grouting holes are arranged on the corresponding end bearing plates at both sides of the web of the I-shaped steel.

[0009] Further, the anti-slide pile is provided with a reinforced concrete beam at the top of the anti-slide pile, and the anchor cable is anchored on the beam.

[0010] Further, the anchor cable hole is coaxially connected by a large hole and a small hole in sequence, and the diameter of the small hole is consistent with the diameter of the free section anchor cable hole.

[0011] Further, the bottom end and the top end of the I-shaped steel respectively extend 1-2 m beyond the bottom crack and the top crack of the pile body, and the lower end of the free section anchor cable hole extends 1-2 m beyond the bottom crack of the pile body.

[0012] Further, the I-shaped steel reinforcing structure is two pieces, the prestressed anchor cable reinforcing structure is one piece, and the prestressed anchor cable reinforcing structure is located between the two I-shaped steel reinforcing structures.

[0013] The second object of the application is achieved by the following technical scheme.

[0014] The application discloses a reinforcing structure for repairing a crack-damaged anti-slide pile, which comprises an I-shaped steel reinforcing structure and a prestressed anchor cable reinforcing structure.

[0015] (1) determining the sliding force E of the anti-slide pile, the distance H0 of the sliding force acting point relative to the bottom crack of the pile body, and the maximum shear force V in each cross section of the anti-slide pile;

[0016] (2) selecting an I-shaped steel type and determining the number n of the I-shaped steel to be used according to formula 1.

[0017]

[0018] In the formula, A0 is the cross-sectional area of the I-beam to be used; V cs is the designed shear bearing capacity of the original anti-slide pile; f is the tensile strength of the I-beam;

[0019] (3) The anchor cable tension F s is determined according to Formula 2.

[0020]

[0021] In the formula, M is the designed bending moment of the original anti-slide pile; h1 is the distance from the center of the anchoring hole to the edge of the compression side of the anti-slide pile; x0 is the height of the compression zone of the anti-slide pile after the tension is applied to the anchor cable, which is determined by Formula 3:

[0022]

[0023] In the formula, a1 is a coefficient, which is 1.0; f c is the designed axial compressive strength of the concrete of the anti-slide pile; b is the width of the tension side of the anti-slide pile; f y is the standard tensile strength of the main reinforcement in the tension zone; A s is the total area of the main reinforcement in the tension zone of the anti-slide pile.

[0024] Through iteration of Formula 2 and Formula 3, the anchor cable tension F s is ultimately determined.

[0025] (4) According to the type of the I-beam selected in step (2), the diameter of the reinforcing hole is determined, the position of the reinforcing hole is marked, and the reinforcing hole is drilled.

[0026] (5) The reinforcing hole is drilled more than 1m-2m above the bottom crack of the pile body, and after the reinforcing hole is flushed with clean water, the water in the reinforcing hole is drained.

[0027] (6) The I-beam is hoisted into the reinforcing hole.

[0028] (7) Cement slurry is injected.

[0029] (8) According to the type of the anchor cable selected in step (3), the diameter of the anchoring hole is determined, the position of the anchoring hole is marked, the free section anchor cable hole is drilled more than 1m-2m above the bottom crack of the pile body, and then the anchoring section anchor cable hole is drilled.

[0030] (9) The anchor cable is hoisted into the anchoring hole, with the anchoring section of the anchor cable located in the anchoring section anchor cable hole and the free section of the anchor cable located in the free section anchor cable hole, and then the anchoring grouting is performed until the anchoring hole is filled.

[0031] (10) After the anchoring grouting reaches the designed strength, the anchor cable is tensioned F s , and the anchor is sealed.

[0032] Further, the step (4) drills the reinforcing hole and takes the anti-slide pile core sample at the same time, and checks the crack position H1 at the bottom of the pile body.

[0033] Further, in the step (6), when the I-beam is provided with end bearing plates at both ends, the grouting pipe is first passed through the grouting holes of the two end bearing plates before the I-beam is hoisted into the reinforcing hole; and the step (7) is a backward high-pressure one-time grouting process.

[0034] Further, a cross beam formwork is erected on the top of the anti-slide pile between the steps (9) and (10), the cross beam reinforcement is bound, the anchor cable is passed through the reserved hole, and then the cross beam is poured, and the anchor cable is subjected to the tension F s before the cross beam reaches the design strength.

[0035] The present application has the following beneficial effects:

[0036] The present application has the following beneficial effects:

[0037] 1. The present application implants the I-beam for grouting reinforcement for the anti-slide pile with crack damage, uses high-pressure grouting to block the crack of the pile body, and repairs, reinforces and strengthens the anti-slide pile through the strong diagonal section shear capacity of the I-beam for the crack damage section, compared with the conventional anti-slide pile repair measures, can effectively solve the problems of disturbance to the unstable slope, unclear reinforcement effect and low construction efficiency, and effectively ensures the stability of the slope during the repair of the anti-slide pile.

[0038] 2. The present application is suitable for crack reinforcement of fully-buried or cantilever anti-slide piles, anchors the high-strength prestressed anchor cable to the pile body, uses the self-anchoring capacity to reinforce the main reinforcement in the tension area, has wide application range, is simple to operate, can quickly improve the integrity of the anti-slide pile, improve the bending bearing capacity of the anti-slide pile, does not excavate and disturb the rock-soil body around the pile, the construction platform only needs the range of the top of the anti-slide pile, has high construction safety, and can effectively meet the requirements of high efficiency, less disturbance and quick effect in the construction of geological disaster treatment and emergency rescue sites.

[0039] 3. In the construction method for repairing and reinforcing the crack of the anti-slide pile, the grouting holes are arranged on both sides of the end bearing plate of the I-beam, one-time grouting reinforcement is carried out on two regions with different depths in a backward manner, the grouting process is simple and fast, the anchor cable hole of the anchoring section is drilled by using the concentric reaming process, the anchor cable hole of the anchoring section is arranged in the form of large holes and small holes staggered in sequence, the anchoring force of the prestressed anchor cable can be better provided through the comprehensive action of the hole wall bonding strength and mechanical engagement, the length of the anchor cable anchoring section is greatly shortened, the prestress loss of the anchor cable is reduced, and the long-term stability of the anchor cable for reinforcing the anti-slide pile is effectively ensured.

[0040] Additional advantages, objects, and features of the application will be apparent to those skilled in the art upon examination of the following specification. It is intended that the application not be limited by the disclosed BRIEF DESCRIPTION OF DRAWINGS

[0041] In order to make the objectives, technical solutions and advantages of the present application clearer, the following will further describe the present application in detail with reference to the accompanying drawings, in which:

[0042] Figure 1 is a front view of a repair and reinforcement structure of a crack-damaged anti-slide pile according to the present application.

[0043] Figure 2 is a left view of a repair and reinforcement structure of a crack-damaged anti-slide pile according to the present application.

[0044] Figure 3 is a cross-sectional view of the repair and reinforcement structure of the crack-damaged anti-slide pile according to the present application. Figure 1

[0045] Figure 4 is a cross-sectional view of the repair and reinforcement structure of the crack-damaged anti-slide pile according to the present application. Figure 1

[0046] Figure 5 is a top view of the I-shaped steel according to the present application. Figure 1

[0047] Figure 6 is a perspective view of the I-shaped steel according to the present application. Figure 1

[0048] Figure 7 is a perspective view of the prestressed anchor reinforcement structure according to the present application. Figure 1

[0049] is a perspective view of a repair and reinforcement structure of a crack-damaged anti-slide pile according to the present application in use. Figure 8

[0050] is a left view of a stress analysis of a repair and reinforcement structure of a crack-damaged anti-slide pile according to the present application. Figure 9

[0051] is a schematic view of a reinforcement of a crack-damaged anti-slide pile by a repair and reinforcement structure of a crack-damaged anti-slide pile according to the present application. Figure 10

[0052] In the figure: anti-slide pile 1; I-shaped steel 2; reinforcement hole 3; anchor cable 41; anchor grouting 42; free section anchor cable hole 43; anchor section anchor cable hole 44; anchor sealing 45; cross beam 5; end bearing plate 6; cement grout 7; grouting hole 8; reserved hole 9; cross beam reinforcement 10. ​​​​​Detailed Implementation

[0053] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be understood that the preferred embodiments are for illustrative purposes only and are not intended to limit the scope of protection of the present invention.

[0054] The principle of this invention is as follows:

[0055] After the anti-slide pile 1 bears the sliding thrust E of the soil and rock behind the pile, due to reasons such as the sliding thrust exceeding the pile's anti-slide bearing capacity, weak shear resistance due to local defects in the pile, or insufficient main reinforcement in the tension zone, the anti-slide pile 1 will experience insufficient shear or bending resistance, resulting in shear failure or fracture failure. When cracks appear in the pile body, the internal steel reinforcement is susceptible to water and air erosion and corrosion, which will greatly weaken the integrity of the pile body and its shear and bending bearing capacity, thus hindering the stability of the supported slope.

[0056] By inserting an I-beam 2 into the cracked section of the pile body, the high tensile strength of the I-beam 2 provides oblique shear resistance; a high-strength prestressed anchor cable 41 is set inside the main reinforcement in the tension zone, and by actively applying prestress and anchoring it in a stable stratum or an intact pile body, a vertically downward active tensile force is added to the main reinforcement in the tension zone, thereby strengthening the stress on the main reinforcement and the bending resistance of the anti-slide pile.

[0057] As attached Figure 9 As shown, the sliding thrust E of the soil and rock mass acts on the pile body after the anti-slide pile 1, at a distance H0 from the lowest edge of the pile body crack, and the original shear force design value V of the anti-slide pile. cs The shear force is mainly provided by the pile body section and the configured stirrups, with the direction opposite to the landslide thrust E. After the I-beam 2 is set in the cracked area of ​​the pile body, the I-beam 2 is subjected to shear tension, and provides shear force fA0 through its tensile strength, with the direction opposite to the landslide thrust E. According to the horizontal force balance:

[0058] EV cs -nfA0=0 (4)

[0059] In the formula, A0 is the required cross-sectional area of ​​the I-beam; V cs f is the design shear bearing capacity of the original anti-slide pile 1; f is the tensile strength of the I-beam 2; n is the number of I-beams 2.

[0060] The required number of I-beams can be obtained from the following formula 5.

[0061]

[0062] Anti-slide pile 1 is generally a rectangular cross-section, but can also be a circular cross-section (the calculation of circular cross-section anti-slide piles generally needs to be converted to rectangular cross-section anti-slide piles). Designed as a bending member, the reinforcement is considered as a singly reinforced rectangular cross-section. The original anti-slide pile's bending capacity is M, provided by the main reinforcement in the tension zone.

[0063]

[0064] To avoid over-reinforcement failure, the height x of the concrete compression zone must satisfy Equation 7:

[0065] αf c bx = f y A s (7)

[0066] Prestress F is applied to the tension zone on the mountainside of anti-slide pile 1. s The concrete compression zone will increase from its original height x to x0. Taking the pile body as rotating around the centerline of the compression zone at the crack in the pile body, the torque balance can be obtained as follows:

[0067]

[0068] The actively applied prestress value F s From Equation 9, we can obtain:

[0069]

[0070] After applying prestressed anchor cable 41, the height of the compression zone of anti-slide pile 1 will become x0. In order to ensure that the applied prestress F s Appropriate reinforcement is necessary to avoid over-reinforcement failure of anti-slide pile 1. The height x0 of the compression zone can be calculated using Equation 10, and the applied prestress value F is finally determined by iterating through Equations 9 and 10. s .

[0071]

[0072] The pile body is made of concrete. Anchor holes are drilled inside the pile body. The prestressed anchor cable 41 is anchored by the friction between the cement grout and the hole wall. Since the hole wall of the mechanically drilled hole is relatively smooth, the bond strength between the hole wall and the grout is insufficient to provide high prestress. Therefore, the concentric reaming drilling process is adopted. The anchor section holes are arranged in a staggered pattern of large holes and small holes. The anchoring force is provided for the prestressing tensioning of the anchor cable by utilizing the friction of the hole wall and the mechanical interlocking effect.

[0073] Specifically, such as Figures 1-10As shown, a kind of crack damage anti-slide pile repair and reinforcement structure, including I-steel reinforcement structure and prestressed anchor reinforcement structure, I-steel reinforcement structure includes the reinforcement hole 3 being vertically located in the pile body of anti-slide pile 1 and being close to the tension side reinforcement of anti-slide pile 1 and I-steel 2, I-steel 2 is implanted in reinforcement hole 3 and its bottom end and top end respectively exceed the bottom crack and top crack of pile body, the long side direction of the web of I-steel 2 is along the shear direction of anti-slide pile 1, and cement slurry 7 is injected in reinforcement hole 3, prestressed anchor reinforcement structure includes anchoring hole and anchor cable 41 being vertically located in the pile body of anti-slide pile 1 or in the pile body of anti-slide pile 1 and stable stratum and being close to the tension side reinforcement of anti-slide pile 1, anchoring hole includes upper free section anchor cable hole 43 and lower anchoring section anchor cable hole 44, the lower end of free section anchor cable hole 43 exceeds the bottom crack of pile body, and the anchoring section and free section of anchor cable 41 are anchored in anchoring section anchor cable hole 44 and free section anchor cable hole 43 respectively through anchoring grouting 42, and anchor cable 41 is sealed in the top of anti-slide pile 1 after prestress is applied, and I-steel reinforcement structure and prestressed anchor reinforcement structure are respectively arranged in the center line symmetry of tension side of anti-slide pile 1.

[0074] Specifically, I-steel reinforcement structure is multiple and even, and multiple I-steel reinforcement structures are arranged in the inside of tension side reinforcement of anti-slide pile 1, and prestressed anchor reinforcement structure is one, and prestressed anchor reinforcement structure is located in the middle of all I-steel reinforcement structures.

[0075] The reinforcement structure of the present application is simple, and the construction process is simple, the crack is blocked by multiple reinforcement holes, the I-steel improves the shear capacity of the cracked section of the pile body, the prestressed anchor cable is used to reinforce the main reinforcement in the tension area of the anti-slide pile, the reinforcement purpose is clear, the pile body structure and reinforcement are not damaged, the original anti-slide pile supporting environment is not disturbed, the integrity and anti-slide bearing capacity of the crack anti-slide pile can be greatly improved, and the stability of the supported slope body is ensured.

[0076] Preferably, I-steel reinforcement structure is two, and prestressed anchor reinforcement structure is one, and prestressed anchor reinforcement structure is located between the two I-steel reinforcement structures.

[0077] I-steel 2 is vertically fixed at both ends and is provided with end bearing plate 6, grouting hole 8 is arranged on the corresponding two end bearing plates 6 on both sides of the web of I-steel 2, and the engagement force between I-steel 2 and the hole wall of reinforcement hole 3 is increased after pouring cement slurry 7 by arranging end bearing plate 6.

[0078] Anti-slide pile 1 has reinforced concrete cross beam 5 passing through anchoring hole in the top, anchor cable 41 is sealed on cross beam 5, and the anchoring strength of anchor cable 41 is enhanced through reinforced concrete cross beam 5.

[0079] Anchoring section anchor cable hole 44 is coaxially connected by large hole and small hole in turn, the hole diameter of small hole is consistent with the hole diameter of free section anchor cable hole 43, and the friction force between anchor cable and hole wall is increased.

[0080] Preferably, the I-beam 2 bottom end and top end respectively exceed the pile body bottom crack and top crack 1-2m, and the free section anchor cable hole 43 lower end exceeds the pile body bottom crack 1-2m.

[0081] The prestressed anchor cable anchoring section adopts full-bonding steel strand, and the free section adopts unbonding steel strand, and a sleeve is provided for protection.

[0082] A repair and reinforcement structure construction method of a crack damage anti-slide pile, comprising the following steps:

[0083] (1) Determine the landslide sliding thrust E on the anti-slide pile 1, the distance H0 of the landslide sliding thrust action point relative to the pile body bottom crack of the anti-slide pile 1, and the maximum shear V in each cross section of the anti-slide pile 1. The specific determination method is the prior art;

[0084] (2) Select the I-beam 2 model, and determine the number n of the I-beam 2 to be used according to formula 1:

[0085]

[0086] In the formula, A0 is the cross-sectional area of the I-beam 2 to be used; V cs is the original anti-slide pile 1 design shear capacity; f is the tensile strength of the I-beam 2;

[0087] (3) Determine the anchor cable 41 tensile force F s according to formula 2:

[0088]

[0089] In the formula, M is the original anti-slide pile 1 bending moment design value; h1 is the distance from the anchoring hole center to the compression side edge of the anti-slide pile 1; x0 is the compression zone height of the anti-slide pile 1 after the tensile force is applied to the anchor cable 41, which is calculated and determined by formula 3:

[0090]

[0091] In the formula, α1 is a coefficient, which is 1.0; f c is the anti-slide pile 1 concrete axial compressive strength design value; b is the width of the tensile side of the anti-slide pile 1; f y is the tensile strength standard value of the tensile zone main reinforcement; A s is the area of all main reinforcements in the tensile zone of the anti-slide pile 1;

[0092] Iterate through formula 2 and formula 3 to finally determine the anchor cable 41 tensile force F s ;

[0093] (4) According to the type of I-beam 2 selected in step (2), the hole diameter of the reinforcing hole 3 is determined, the position of the reinforcing hole 3 is marked, the drilling machine is fixed on the top platform of the anti-slide pile, and the reinforcing hole 3 is drilled hole by hole, while the core sample of the anti-slide pile is taken, and the position H1 of the bottom crack of the pile body is reviewed;

[0094] (5) The reinforcing hole 3 is drilled more than 1m-2m beyond the bottom crack of the pile body, and after the reinforcing hole 3 is washed with clean water, the water in the reinforcing hole 3 is drained;

[0095] (6) The end bearing plate 6 is welded to both ends of the I-beam 2, the grouting pipe passes through the grouting holes on both sides of the end bearing plate 6, and the whole is hoisted and placed into the reinforcing hole 3;

[0096] (7) The reinforcing hole 3 is grouted by using the backward high-pressure one-time grouting process, and as the cement slurry 7 is pumped in, the grouting pipe is gradually pulled out until the hole is opened, and steps (4)-(7) are repeated to complete all the I-beam reinforcing structures;

[0097] (8) According to the type of anchor cable 41 selected in step (3), the hole diameter of the anchoring hole is determined according to the selected type of anchor cable 41, the position of the anchoring hole is marked, the free section anchor cable hole 43 is drilled, and the anchoring section anchor cable hole 44 is drilled by using the concentric reaming drilling process, which is in the form of large and small holes staggered in turn;

[0098] (9) The anchor cable 41 is hoisted and placed into the anchoring hole, and the anchoring section of the anchor cable is located in the anchoring section anchor cable hole 44, and the free section of the anchor cable is located in the free section anchor cable hole 43, and then the anchoring grouting 42 is performed until the anchoring hole is opened;

[0099] (10) A cross beam formwork is erected at the top end of the anti-slide pile, the cross beam reinforcement 10 is bound, the anchor cable passes through the reserved hole 9, and then the pile top cross beam 5 is poured, and after the anchoring grouting 42 and the pile top cross beam 5 reach the design strength, the anchor cable 41 is subjected to a tension force F s The anchor is sealed, and the reinforcement measures are completed.

[0100] The process and results of repairing and reinforcing the anti-slide pile with crack damage in a landslide site by using the method of the present application are shown below.

[0101] As shown in Figure 10 , in this embodiment, the cross-sectional size of the original supporting anti-slide pile 1 of the landslide is 3m x 2m, the pile length is 22m, the cantilever end is 10m, the center distance of the anti-slide pile 1 is 6m, the horizontal displacement of the anti-slide pile 1 at 11m is shown by the data of the deep displacement monitoring hole behind the pile, and combined with acoustic detection, it is found that the anti-slide pile 1 has cracked, the original anti-slide pile 1 has a designed shear bearing capacity V cs = 8669.43kN, and a designed bending bearing capacity M = 41150kN.

[0102] According to the above parameters and geological exploration data, the slide force E of the slide acting on the anti-slide pile 1 is 6600 kN, the acting position H0 is 6.4 m, the maximum bending moment of the section is 42240 kN·m, and the maximum shear force V of the section of the anti-slide pile 1 is 9185.03 kN.

[0103] The 10# I-beam 2 is used to reinforce the anti-slide pile, and the standard tensile strength f of the 10# I-beam 2 is 215 N / mm 2 The number n of I-beams 2 required by the anti-slide pile is calculated by the formula in step 2.

[0104] The number n is rounded to 2.

[0105] Therefore, it is determined to use two 10# I-beams 2 to reinforce the anti-slide pile, and the hole diameter of the reinforcing hole 3 is 130 mm.

[0106] The tension force F of the prestressed anchor cable 41 is determined by the formula in step 3. s And x0, where h1=1.8 m, b=2 m, α1=1.0, f c =14.3 N / mm 2 , f y =435 N / mm 2 , A s =36191.1 mm 2 , and the formula is calculated.

[0107]

[0108]

[0109] Through iteration:

[0110]

[0111] Finally, the calculation results are:

[0112] F s =893 KN

[0113] Therefore, it is determined to use 8 anchor cables 41, with a single tension of 115 kN, a total tension anchoring force of 920 kN, and a hole diameter of 130 mm.

[0114] As shown in Figure 7 , after the I-beam 2 reinforcement is completed according to steps 4-7, the 130 mm diameter free section anchor hole 43 is made according to step 8, with a length of 12 m, and after passing through the pile body crack about 1 m, the anchor hole 44 is made by using a concentric reaming drill, with a reaming hole diameter of 150 mm, and the anchor hole 44 has a length of 6 m, and the total length of the anchor cable is 18 m.

[0115] The anchor cable 41 is installed according to step (9), and after installation, the anchoring grouting 42 is performed until the orifice, and the anchoring grouting 42 uses M30 pure cement grout;

[0116] According to step (10), the cross beam template is erected at the top end of the anti-slide pile, the cross beam 5 has a section size of 50cm*50cm and a length of 2m, the cross beam reinforcement 10 is bound, the anchor cable 41 is pre-buried into the reserved hole 9 of the cross beam 5 after being passed through the PVC pipe, and then the cross beam 5 at the top of the pile is poured.

[0117] After the anchoring grouting 42 and the concrete of the cross beam 5 at the top of the pile reach the design strength, the anchor cable 41 is prestressed and then sealed, and the reinforcement is completed.

[0118] The cement grout 7 adopted in the application has a strength not less than the concrete strength grade of the anti-slide pile 1.

[0119] The crack anti-slide pile 1 is repaired by using the reinforcement method of the application, the repair of the anti-slide pile can be completed without disturbing the unstable slope body, the anti-slide pile 1 is drilled and anchored gradually through the theoretical calculation of the I-shaped steel 2 and the prestressed anchor cable 41, the steps are clear, the operation is simple, the integrity of the anti-slide pile can be quickly improved, the shear and bending bearing capacity of the anti-slide pile is improved, and the requirements of construction safety, high efficiency, less disturbance and fast effect in the geological disaster treatment and emergency rescue work site are effectively met.

[0120] Finally, it should be noted that the above examples are only used to illustrate the technical solutions of the application and are not limited. Although the application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the application can be modified or replaced equivalently without departing from the purpose and scope of the technical solutions, and they should be covered in the scope of the claims of the application.

Claims

1. A repair and reinforcement structure for crack-damaged anti-slide piles, characterized in that: The I-shaped steel reinforcing structure comprises reinforcing holes (3) and I-shaped steels (2) vertically arranged in the pile body of the anti-slide pile (1) and close to the reinforcing steel bars on the tension side of the anti-slide pile (1), the I-shaped steels (2) are implanted into the reinforcing holes (3) and the bottom end and the top end of the I-shaped steels (2) respectively exceed the bottom crack and the top crack of the pile body, the long side direction of the web of the I-shaped steel (2) is arranged along the shearing direction of the anti-slide pile (1), and the reinforcing holes (3) are filled with cement slurry (7); the prestressed anchor cable reinforcing structure comprises anchor holes and anchor cables (41) vertically arranged in the pile body of the anti-slide pile (1) or in the pile body of the anti-slide pile (1) and the stable stratum and close to the reinforcing steel bars on the tension side of the anti-slide pile (1), the anchor holes comprise upper free section anchor cable holes (43) and lower anchor section anchor cable holes (44), the lower end of the free section anchor cable hole (43) exceeds the bottom crack of the pile body, and the anchor section and the free section of the anchor cable (41) are respectively anchored in the anchor section anchor cable hole (44) and the free section anchor cable hole (43) through anchor grouting (42); the anchor cable (41) is anchored on the top of the anti-slide pile (1) after prestress is applied, and the I-shaped steel reinforcing structure and the prestressed anchor cable reinforcing structure are respectively arranged in the center line of the tension side of the anti-slide pile (1) in a symmetrical manner. End bearing plates (6) are vertically and fixedly arranged at the two ends of the I-shaped steel (2), and grouting holes (8) are respectively arranged on the two end bearing plates (6) corresponding to the two sides of the web of the I-shaped steel (2). The anchor section anchor cable hole (44) is coaxially connected by large holes and small holes in sequence, and the hole diameter of the small hole is consistent with the hole diameter of the free section anchor cable hole (43).

2. The structure for repairing and reinforcing the anti-slide pile with crack damage according to claim 1, characterized in that: The anti-slide pile (1) is provided with a reinforced concrete cross beam (5) passing through the anchor hole on the top of the anti-slide pile (1), and the anchor cable (41) is anchored on the cross beam (5).

3. The structure for repairing and reinforcing a crack-damaged anti-slide pile according to claim 1, wherein: The bottom end and the top end of the I-shaped steel (2) respectively exceed the bottom crack and the top crack of the pile body by 1-2 m, and the lower end of the free section anchor cable hole (43) exceeds the bottom crack of the pile body by 1-2 m.

4. The structure for repairing and reinforcing the anti-slide pile with crack damage according to any one of claims 1-3, characterized in that: The I-shaped steel reinforcing structure is two pieces, the prestressed anchor cable reinforcing structure is one piece, and the prestressed anchor cable reinforcing structure is located between the two I-shaped steel reinforcing structures.

5. The construction method of the repair and reinforcement structure of the anti-slide pile with crack damage according to any one of claims 1-4, characterized in that: The method comprises the following steps: (1) determining the landslide downward thrust force on the anti-slide pile (1) the distance of the landslide downward thrust force action point from the bottom crack of the pile body of the anti-slide pile (1) 、 the maximum shear force on each cross section of the anti-slide pile (1) ; (2) Selecting the type of I-beam (2) and determining the number of I-beams (2) to be used according to equation (1) : （1） In the formula, is the cross-sectional area of the I-beam (2) to be used; is the designed shear bearing capacity of the original anti-slide pile (1); is the tensile strength of the I-beam (2). (3) Determine the tension of the anchor cable (41) to be used according to formula (2) : （2） In the formula, is the bending moment design value of the original anti-slide pile (1); is the distance from the center of the anchoring hole to the edge of the compression side of the anti-slide pile (1), is the height of the compression zone of the anti-slide pile (1) after the tensioning force is applied to the anchor cable (41), which is determined by formula (3): （3） In the formula, is a coefficient, taken as 1.0; is the design value of the axial compressive strength of the concrete of the anti-slide pile (1); is the width of the tensile side of the anti-slide pile (1); is the standard value of the tensile strength of the main reinforcement in the tensile zone; is the area of all main reinforcements in the tensile zone of the anti-slide pile (1); Through iteration of formula (2) and formula (3), the anchor cable (41) tension to be adopted is finally determined ; (4) according to the type of the I-shaped steel (2) selected in step (2), the hole diameter of the reinforcing hole (3) is determined, the position of the reinforcing hole (3) is marked, and the reinforcing hole (3) is drilled; (5) the reinforcing hole (3) is drilled to exceed the bottom crack of the pile body by 1-2 m, the reinforcing hole (3) is washed with clean water and then the water in the reinforcing hole (3) is drained; (6) the I-shaped steel (2) is hoisted and placed into the reinforcing hole (3); (7) cement slurry (7) is injected; (8) according to the type of the anchor cable (41) selected in step (3), the hole diameter of the anchor hole is determined according to the type of the anchor cable (41) selected, the position of the anchor hole is marked, the free section anchor cable hole (43) is drilled and exceeds the bottom crack of the pile body by 1-2 m, and then the anchor section anchor cable hole (44) is drilled; (9) the anchor cable (41) is hoisted and placed into the anchor hole and the anchor section of the anchor cable is located in the anchor section anchor cable hole (44) and the free section of the anchor cable is located in the free section anchor cable hole (43), and then the anchor grouting (42) is performed until the hole of the anchor hole is reached; (10) After the anchoring grouting (42) reaches the design strength, the tension of the anchor cable (41) is applied Post-anchoring.

6. The construction method of a repair and reinforcement structure of a crack-damaged anti-slide pile according to claim 5, characterized in that: The step (4) drills the reinforcing hole (3) and takes the anti-slide pile core sample to check the crack position of the bottom of the pile body .

7. The construction method of a repair and reinforcement structure of a crack-damaged anti-slide pile according to claim 5, characterized in that: When the end bearing plates (6) are arranged at both ends of the I-beams (2) in the step (6), the grouting pipes are first passed through the grouting holes (8) of the end bearing plates (6) before the I-beams (2) are hoisted into the reinforcing holes (3), and then the I-beams (2) are hoisted into the reinforcing holes (3) as a whole; and the cement grouting process in the step (7) is a backward high-pressure one-time grouting process.

8. The construction method of a repair and reinforcement structure of a crack-damaged anti-slide pile according to claim 5, characterized in that: Between step (9) and step (10), the beam formwork is erected on the top of the anti-slide pile (1), the beam reinforcement (10) is bound, the anchor cable (41) is passed through the reserved hole (9), and then the beam (5) is poured The beam (5) needs to reach the design strength.

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