CN102330431A

CN102330431A - Flexible support structure of pre-stress anchor rod for lattice type frame and construction method of flexible support structure

Info

Publication number: CN102330431A
Application number: CN201110164260A
Authority: CN
Inventors: 朱彦鹏; 周勇; 李忠; 董建华; 马天忠; 叶帅华; 毕东涛; 任永忠
Original assignee: Lanzhou University of Technology
Current assignee: Lanzhou University of Technology
Priority date: 2011-06-16
Filing date: 2011-06-16
Publication date: 2012-01-25

Abstract

Lattice frame prestressed anchor flexible support structure and construction method thereof, beams (1) and columns (2) constitute a lattice frame, prestressed anchors (3) pass through the beams (1) and columns (2) Wrap cement mortar around the anchor section (5) of the prestressed anchor rod (3), wrap cement mortar around the plastic sleeve (12), and the anchor head (4) connects the end of the prestressed anchor rod (3) Anchored at the intersection of the beam (1) and the column (2), anchored in the stable soil layer through the anchor section (5); the steps of the method are: (1) making and constructing the prestressed anchor rod (3); (2) pouring and pressing the crown beam (6), column (2) and beam (1); (3) prestressing the steel anchor rod (10); (4) following this step to construct the prestressed Stress anchor rods (3), beams (1), columns (2), and complete the tensioning and anchoring of prestressed anchor rods (3) in each layer.

Description

Lattice type portal frame prestressed anchor flexible support structure and job practices thereof

Technical field

The present invention relates to the slow loess slope supporting field of the gradient.

Background technology

In the past, to the loess area gradient the support technology of slow highway, railway and building slope adopt the gravity barricade more.The way of gravity barricade can adopt free stone masonry, also can adopt plain concrete to build and form, and this kind method mainly relies on deadweight and the rigidity of barricade to come the lateral pressure of the soil body after the resistance wall.

The shortcoming of this support technology is: 1) from great; 2) rigidity is big, poor seismic behavior; 3) resistance to overturning is poor, and resistance to capsizing is not enough.Therefore, the situation of overturning of retaining wall and slippage often occurs, influence the safety of engineering services,, strengthen its anti-seismic performance, adopt lattice type portal frame prestressed anchor flexible support method that side slope is carried out supporting in order to improve the stability of loess slope.

Summary of the invention

The objective of the invention is through a kind of lattice type portal frame prestressed anchor flexible support framework and job practices thereof are provided; Make the slow loess slope that potential sliding rupture trend is arranged of the original gradient be in stable state, prevent that loess slope from producing destruction under rainfall state or geological process.

The present invention is lattice type portal frame prestressed anchor flexible support structure and job practices thereof; Its supporting and protection structure middle cross beam 1, column 2 constitute lattice type portal frame; Prestressed anchor 3 passes the crossover sites of crossbeam 1 and column 2; Around the anchoring section 5 of prestressed anchor 3, wrap up cement mortar, on the free section 11 of prestressed anchor 3, be coated with one deck anti-corrosion material, suit plastic bushing 12 outside anti-corrosion material; Around plastic bushing 12, wrap up cement mortar; Anchor head 4 fixes on the crossover sites of crossbeam 1 and column 2 with the end anchor of prestressed anchor 3, and the suffered soil pressure of crossbeam 1, column 2 reaches the anchoring section 5 of prestressed anchor 3 through anchor head 4, and is anchored in the steady soil through anchoring section 5.

Job practices of the present invention the steps include:

(1) making and construction prestressed anchor 3: at first in soil layer, offer hole 8; To be welded on the reinforcing bar anchor tie 10 medium-height trestle 9; Reinforcing bar anchor tie 10 is positioned in the hole 8, injects cement mortar, on the free section 11 of reinforcing bar anchor tie 10, smear anti-corrosion material at anchoring section 5; Put plastic bushing 12 in free section 11 then, in the hole 8 of free section 11, inject cement mortar at last;

(2) pour into a mould bear down on one hat beam 6, column 2 and crossbeam 1: at the design attitude place formwork of first root post 2 and the first horizontal row beam 1, the cage of reinforcement and the concreting of colligation crossbeam 1, column 2 in the groove that formwork forms;

(3) concrete strength of treating crossbeam 1, column 2 reaches 85% and reinforcing bar anchor tie 10 is carried out prestressed stretch-draw when above; Form prestressed anchor 3; Will be locked with ground tackle 13 with the anchor head 4 that prestressed anchor 3 is fastenedly connected, do the concrete spray coating 14 that is used to protect anchor head 4 and ground tackle 13 then;

(4), and accomplish the stretch-draw and the anchoring of each layer prestressed anchor 3 according to this step the construct prestressed anchor 3 and crossbeam 1, column 2 of next work plane;

(5) according to the bottom of (2) step operation construction column 2 to column 2, construction crossbeam 1 is made all the other prestressed anchors 3 and is accomplished corresponding operation at design attitude place, the bottom of column 2;

(6) make foundation pile 7 in the corresponding position, bottom of column 2: put into reinforcing cage in the stake hole of offering, reinforcing bars in the bottom protruding bar of column 2 and the foundation pile 7 are welded to connect, pour into a mould foundation pile 7.

The invention has the beneficial effects as follows: adopt the lattice type portal frame prestressed anchor to carry out supporting through the loess slope that potential sliding rupture trend is arranged that the original gradient is delayed, and reinforced anchor bolt is applied prestressing force, thereby improved the stability of side slope; Lattice girder that on loess slope, applies and prestressed anchor can be controlled the slippage and the distortion of side slope effectively, improve its anti-seismic performance simultaneously; Overcome that traditional gravity barricade cost is high, engineering quantity is big, stability is low, to shortcomings such as environmental disruption are big; The safety that perturbation to side slope in work progress is little, the employing reverse construction has guaranteed work progress; Through grass planting in the sash that forms at lattice girder, can reduce the side slope soil erosion, reach the purpose of ecological revetment; Technology is simple, is convenient to use.

Description of drawings

Fig. 1 is the elevation of structure of the present invention, and Fig. 2 is the sectional side view among Fig. 1, and Fig. 3 is a prestressed anchor detail of construction of the present invention, also is construction reference figure, the reinforcing bar anchor tie 12 among the figure in construction and the name after applying prestressing force be called prestressed anchor 3.

The specific embodiment

The present invention is lattice type portal frame prestressed anchor flexible support structure and job practices thereof; Its supporting and protection structure middle cross beam 1, column 2 constitute lattice type portal frame; Prestressed anchor 3 passes the crossover sites of crossbeam 1 and column 2; Around the anchoring section 5 of prestressed anchor 3, wrap up cement mortar, on the free section 11 of prestressed anchor 3, be coated with one deck anti-corrosion material, suit PVC plastic bushing 12 outside anti-corrosion material; Around PVC plastic bushing 12, wrap up cement mortar; Anchor head 4 fixes on the crossover sites of crossbeam 1 and column 2 with the end anchor of prestressed anchor 3, and the suffered soil pressure of crossbeam 1, column 2 reaches the anchoring section 5 of prestressed anchor 3 through anchor head 4, and is anchored in the steady soil through anchoring section 5.

The anchor pole inclination angle that prestressed anchor 3 is become with horizontal plane is 5 °～15 °.

When implementing, adopt contrary sequence method, section construction, from top to bottom successively promptly, section construction, the step of its job practices is:

(1) making and construction prestressed anchor 3: at first in soil layer, offer hole 8; To be welded on the reinforcing bar anchor tie 10 medium-height trestle 9; Reinforcing bar anchor tie 10 is positioned in the hole 8, injects cement mortar, on the free section 11 of reinforcing bar anchor tie 10, smear anti-corrosion material at anchoring section 5; Put PVC plastic bushing 12 in free section 11 then, in the hole 8 of free section 11, inject cement mortar at last;

Claims

1. Lattice frame prestressed anchor flexible support structure, characterized in that the beam (1) and column (2) in the support structure form a lattice frame, and the prestressed anchor (3) passes through the beam (1) Wrap cement mortar around the anchoring section (5) of the prestressed anchor (3) at the intersection with the column (2), and coat a layer of anti-corrosion material on the free section (11) of the prestressed anchor (3), Set the plastic casing (12) outside the anticorrosion material, wrap the cement mortar around the plastic casing (12), and the anchor head (4) anchors the end of the prestressed anchor rod (3) on the beam (1) and the column (2), the earth pressure on the beam (1) and column (2) is transmitted to the anchor section (5) of the prestressed anchor rod (3) through the anchor head (4), and passes through the anchor section (5) Anchored in a stable soil layer.

2. The lattice frame prestressed anchor flexible support structure according to claim 1, characterized in that the inclination angle between the prestressed anchor (3) and the horizontal plane is 5° to 15°

3. The construction method of the lattice frame prestressed anchor flexible support structure, the steps are:

(1) Fabrication and construction of the prestressed anchor (3): firstly, a hole (8) is opened in the soil layer, the centering bracket (9) is welded on the steel anchor rod (10), and the steel anchor rod (10) is placed In the hole (8), inject cement mortar into the anchor section (5), apply anti-corrosion material on the free section (11) of the steel anchor rod (10), and then put a plastic sleeve (12) on the free section (11) , finally inject cement mortar in the hole (8) of the free section (11);

(2) Casting and pressing crown beam (6), column (2) and beam (1): set up the formwork at the design position of the first column (2) and the first row of beams (1), and form it in the formwork Bind the steel skeleton of the beam (1) and the column (2) in the groove and pour concrete;

(3) When the concrete strength of the crossbeam (1) and the column (2) reaches more than 85%, the steel anchor tie rod (10) is prestressed and stretched to form a prestressed anchor rod (3). The anchor head (4) tightly connected with the prestressed anchor rod (3) is locked, and then the concrete spraying layer (14) used to protect the anchor head (4) and the anchorage (13) is used;

(4) Construct the prestressed anchor rod (3) and beam (1) and column (2) of the next working face according to this step, and complete the tensioning and anchoring of the prestressed anchor rod (3) of each layer;

(5) Construct the column (2) to the bottom of the column (2) according to the step (2), construct the beam (1) at the design position of the bottom of the column (2), and make the remaining prestressed anchor rods (3) And complete the corresponding process;

(6) Make the foundation pile (7) at the corresponding position at the bottom of the column (2): put the reinforcement cage in the pile hole opened, and put the extended steel bar at the bottom of the column (2) into the foundation pile (7) Reinforcement welded connection, pouring foundation pile (7).