CN111926866A - Obstacle encountering implementation method for reinforcing isolation pile in shield construction near high-speed railway - Google Patents

Abstract

The invention relates to the technical field of railway construction protection, in particular to an obstacle implementation method for reinforcement of isolation piles adjacent to high-speed railway shield construction. Depending on the positional relationship, different types of isolation piles are used for reinforcement. Aiming at the problem that the shield construction of the nearby high-speed railway passes through various complex obstacles, a targeted isolation pile reinforcement scheme is proposed, which is safe, economical, scientific and feasible. It can effectively control the deformation of the high-speed railway line caused by the shield construction and ensure the operation of the adjacent high-speed railway Safety and construction safety of new shield tunnels; not only can provide a useful reference for similar projects, but also have important significance for improving the construction level and technological innovation ability of adjacent high-speed railway construction, and leading my country's high-speed railway operation safety assurance technology.

Description

A kind of obstacle implementation method for reinforcement of isolation piles in shield construction near high-speed railway

technical field

The invention relates to the technical field of railway construction protection, in particular to an obstacle implementation method for reinforcement of isolation piles adjacent to shield construction of high-speed railways.

Background technique

With the rapid development of my country's economy and the rapid development of urbanization, it is inevitable to carry out adjacent engineering activities around the existing high-speed railway, and the adjacent engineering will inevitably have a certain impact on the operation of the existing high-speed railway. However, high-speed railways have extremely strict requirements on off-line engineering deformation. For ballastless high-speed railways, the deformation of high-speed railway lines caused by the construction of adjacent high-speed railways is only allowed to be 2mm. How to effectively control the impact of adjacent engineering construction on the structure and driving safety of the high-speed railway line has become a problem that must be faced in the construction of high-speed railways. In the shield construction of adjacent high-speed railways, portal isolation piles are often used for reinforcement, but during the layout process It is often impossible to implement existing structures (structures) such as roads, bridge pier foundations, pipelines, etc. Therefore, for shield construction near high-speed railways, it is urgent to propose an implementation method for isolation piles in case of obstacles to effectively control the impact of shield construction. The impact of the high-speed railway ensures the safety of the structure and traffic under the high-speed railway line.

SUMMARY OF THE INVENTION

The purpose of the present invention is to propose an implementation method for the reinforcement of isolation piles in shield construction near high-speed railways in case of obstacles. It can effectively reduce the impact of shield construction on nearby objects to be protected and ensure construction safety.

The object of the present invention can be realized through the following technical solutions:

A method for implementing obstacles in the reinforcement of isolation piles adjacent to shield construction of high-speed railways, comprising:

In the process of shield tunnel construction near the high-speed railway, different types of isolation piles are used for reinforcement according to the difference in the positional relationship between the protected object and the disconnected plane of the isolation pile.

Preferred include:

S1: First, determine the diameter, length, spacing of bored piles, and the size and spacing of transverse braces through numerical calculation;

S2: In the ordinary section of shield construction adjacent to the protected object, use portal isolation piles for reinforcement; when the object to be protected is located on the same side of the isolation pile disconnection, use L-shaped isolation piles for reinforcement; when the protected object is located in the isolation pile Double-row isolation piles are used for reinforcement when the pile is on the opposite side of the disconnection; when encountering complex obstacles that are continuously distributed, a combination of L-shaped isolation piles and double-row isolation piles is used for reinforcement.

More preferably, the portal isolation pile is obtained by the following method: constructing a row of bored cast-in-situ piles at intervals on both sides of the shield tunnel, the top of the bored cast-in-situ pile is provided with a crown beam, and the boreholes on both sides are provided with a crown beam. The cast-in-place piles are connected by transverse braces to form portal isolation piles.

More preferably, the L-shaped isolation pile is obtained by the following method:

A crown beam is set on the top of the bored cast-in-place pile, and horizontal diagonal braces are set between the non-disconnected portal isolation piles, and horizontal bracing is used to connect the horizontal diagonal braces to form an L-shaped isolation pile.

More preferably, the double-row isolation piles are obtained by the following methods:

First, two rows of front and rear bored cast-in-place piles are set, crown beams are set on the top of the bored cast-in-situ piles, tie beams are set between the front and rear bored cast-in-situ piles, and the rear row of piles are connected with the portal isolation piles to form double-row isolation piles .

Preferably, the protected objects include but are not limited to high-speed rail bridge pier foundations.

Preferably, a protective tube is provided at the bottom of the isolation pile.

In some preferred specific embodiments of the present invention, a method for implementing obstacles in the reinforcement of gate-type isolation piles adjacent to shield construction of high-speed railways includes the following working conditions:

(1) In the ordinary section of shield construction adjacent to the high-speed railway: construct bored piles on both sides of the shield section, set up crown beams on the top, and connect the rows of piles on both sides with transverse braces to form portal isolation piles.

(2) When the protected object is located on the same side of the disconnection point of the isolation pile: construct a bored cast-in-place pile to the protected object at the disconnection point to the opposite side, set a crown beam on the top, and isolate it from the door type at the non-disconnection point Horizontal diagonal bracing is arranged between the piles, and horizontal bracing is arranged between the diagonal bracing to improve the stability of the diagonal bracing to form an L-shaped isolated pile. If the L-shaped isolation pile does not meet the extension conditions, methods such as appropriately reducing the pile diameter and following up the steel casing to form a pile can be used to ensure that the extension of the isolation pile meets the conditions.

(3) When the protected object is located on the opposite side of the disconnection of the isolation pile: construct two rows of bored cast-in-place piles on the opposite side of the disconnection, set a crown beam on the top, set a tie beam between the front and rear rows of piles, and set the back row of piles with the common The segment gate type isolation piles are connected to form double row isolation piles. If the front row of double-row isolation piles is too close to the protected object, the installation of isolation piles can be ensured by using steel casings to follow up to form piles in difficult areas.

(4) When encountering complex obstacles with continuous distribution, the two methods in (2) and (3) can be used in combination.

The diameter, length, and spacing of the above-mentioned isolation piles can be comprehensively determined through numerical calculation under the conditions of meeting safety requirements, economic requirements, and construction feasibility.

The second aspect of the present invention discloses the application of the above method in the technical field of railway construction protection.

On the basis of conforming to common knowledge in the art, the above preferred conditions can be combined arbitrarily without departing from the concept and protection scope of the present invention.

Compared with the prior art, the present invention has the following significant advantages and effects:

Aiming at the problem that the shield construction of the nearby high-speed railway passes through various complex obstacles, a targeted isolation pile reinforcement scheme is proposed, which is safe, economical, scientific and feasible. It can effectively control the deformation of the high-speed railway line caused by the shield construction and ensure the operation of the adjacent high-speed railway Safety and construction safety of new shield tunnels; not only can provide a useful reference for similar projects, but also have important significance for improving the construction level and technological innovation ability of adjacent high-speed railway construction, and leading my country's high-speed railway operation safety assurance technology.

Description of drawings

Fig. 1 is the implementation schematic diagram of the isolation pile encountering obstacles of the present invention;

Fig. 2 is a schematic diagram of the implementation of portal isolation piles at the intersection of shield tunnels and existing roads;

Figure 3 is a schematic diagram of the implementation of gate isolation piles for shield construction of pier foundations adjacent to existing bridges at a super close distance;

In the figure, 1—shield tunnel, 2—bored pile, 3—crown beam, 4—cross brace, 5—object to be protected, 6—diagonal brace, 7—tie beam, 8—high-speed rail bridge pier foundation, 9 -L-shaped isolation pile, 10-road, 11-double row isolation pile, 12-existing bridge pier foundation.

Detailed ways

The technical solutions of the present invention will be described in detail below with reference to the accompanying drawings and embodiments, but the present invention is not limited to the scope of the described embodiments.

As shown in Figure 1, a method of implementing obstacles for reinforcement of isolation piles adjacent to shield construction of high-speed railways is specifically divided into:

Firstly, through numerical calculation, determine the diameter, length, spacing of bored piles, and the size and spacing of transverse braces.

In the ordinary section of shield construction near the high-speed railway, a row of bored cast-in-place piles 2 are constructed at certain intervals on both sides of the shield tunnel 1, and crown beams 3 are set on the top. piles, so as to reduce the impact of shield construction near the object to be protected 5 , and the object to be protected includes but is not limited to the high-speed rail bridge pier foundation 8 .

When the protected object is located on the same side of the disconnection of the isolation pile, as shown in Figure 2, at the intersection of shield tunnel 1 and existing road 10, the portal isolation pile cannot be continuously installed, so the L-shaped isolation pile 9 is used. The plan is to protect the high-speed railway pier 8, using bored piles 2 with a certain spacing to extend the "L" type protection pile to the opposite side of the pier 8 cap, and set the crown beam 3 on the top, and the non-disconnected portal isolation pile. Horizontal diagonal braces 6 are arranged between the diagonal braces, and horizontal braces are arranged between the diagonal braces to improve the stability of the diagonal braces. In order to reduce the impact of construction on the deformation of the Shanghai-Kunming high-speed railway bridge pier 8, all the protective bored piles within 6m from the Shanghai-Kunming high-speed railway bridge pile foundation shall be constructed by the method of full casing follow-up; All the protective bored piles within the scope are constructed by the method of partial follow-up of the casing. The follow-up range of the casing is from the surface to the bottom of the silty silty clay layer, so as to reduce the impact of the hole-forming process of the isolation pile on the Shanghai-Kunming high-speed railway bridge. influences.

When the protected object is located on the opposite side of the disconnection of the isolation pile, as shown in Figure 3, the shield tunnel 1 is relatively close to the existing bridge pier 12, and the isolation pile is unconditionally implemented there, so the high-speed railway bridge pier 8 is isolated near the foundation 8. The piles are double-row isolation piles 11, two rows of bored cast-in-place piles 2 are constructed on the opposite side of the disconnection, crown beams 3 are arranged on the top, tie beams 7 are arranged between the front and rear rows of piles, and the rear row of piles are in line with the common section portal isolation piles. The distance between the double-row isolation piles 11 and the tie beams 7 between the double-row isolation piles 11 can be determined by combining various factors through numerical calculation. In difficult areas, steel casings are used to follow up to form piles to ensure the installation of isolation piles.

When encountering complex obstacles that are continuously distributed, the L-shaped isolation piles 9 and the double-row isolation piles 11 can be used in combination.

The above description of the embodiments is for the convenience of those of ordinary skill in the art to understand and apply the present invention. It will be apparent to those skilled in the art that various modifications to these embodiments can be readily made, and the general principles described herein can be applied to other embodiments without inventive step. Therefore, the present invention is not limited to the embodiments herein, and improvements and modifications made by those skilled in the art according to the disclosure of the present invention without departing from the scope of the present invention should all fall within the protection scope of the present invention.

Claims (8)

1. A barrier encountering implementation method for reinforcing an isolation pile in shield construction close to a high-speed railway is characterized by comprising the following steps of:

in the shield construction process near the high-speed railway, different types of isolation piles are adopted for reinforcement according to different position relations between a protected object and the isolation pile disconnection plane.

2. The method of claim 1, comprising:

s1: firstly, determining the diameter, the length and the spacing of the bored pile and the size and the spacing of the cross braces through numerical calculation;

s2: reinforcing a shield construction common section close to a protected object by adopting a gate type isolation pile; when the object to be protected is positioned at the same side of the disconnected position of the isolation pile, the L-shaped isolation pile is adopted for reinforcement; when the protected object is positioned on the opposite side of the disconnected position of the isolation piles, reinforcing by adopting double rows of isolation piles; when complex obstacles which are continuously distributed are encountered, the L-shaped isolation piles and the double rows of isolation piles are combined for reinforcement.

3. The method of claim 2, wherein the door-type spacer pile is obtained by: and constructing a row of cast-in-situ bored piles at two sides of the shield tunnel at intervals respectively, wherein the top of each cast-in-situ bored pile is provided with a crown beam, and the cast-in-situ bored piles at two sides are connected by adopting cross braces to form a gate type isolation pile.

4. The method according to claim 2, wherein the L-shaped spacer pile is obtained by:

and arranging a crown beam at the top of the cast-in-situ bored pile, arranging horizontal inclined struts between the gate type isolation piles at the non-disconnected positions, and connecting the horizontal inclined struts by adopting cross struts to form the L-shaped isolation pile.

5. The method of claim 2, wherein the double row of spacer piles is obtained by:

the method comprises the following steps of firstly arranging front and rear rows of cast-in-situ bored piles, arranging a crown beam at the top of each cast-in-situ bored pile, arranging a tie beam between the front and rear cast-in-situ bored piles, and connecting the rear row of piles with a gate type isolation pile in a sequential manner to form double rows of isolation piles.

6. The method of claim 1, wherein the protected object is a high-speed railway pier footing.

7. The method of claim 1, wherein the bottom of the spacer pile is provided with a casing.

8. Use of the method according to any one of claims 1 to 7 in the technical field of railway construction protection.

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