CN116556204A - A construction method of V-shaped pier prestressed rods - Google Patents

Abstract

The invention relates to a construction method of a V-shaped pier prestress pull rod, wherein 3 layers of pull rods are penetrated between templates at two sides of a pier body, a first layer of pull rods are arranged below 1/3 of the height of the V-shaped pier, a second layer of pull rods are arranged above 1/3 of the height of the V-shaped pier and below 2/3 of the height, and a third layer of pull rods are arranged above 2/3 of the height of the V-shaped pier and below the top height; pouring pier body concrete in 3 layers, and stretching a pull rod corresponding to each layer before pouring; and 4 layers of blocks 0 on the pier top are poured, 3 layers of pull rods are stretched from bottom to top before each layer of blocks are poured, and finally, after the prestress construction of the blocks 0 is finished, the pull rods are removed. According to the invention, the horizontal component force of the pier body can be balanced by arranging the prestress pull rod and applying different prestress at different construction stages of the V-shaped pier, and the root of the V-shaped pier can be effectively prevented from generating cracks.

Description

A construction method of prestressed tie rods for V-shaped piers

technical field

The invention belongs to the technical field of bridge construction, and relates to a V-shaped pier prestressed rod construction method, which is mainly used to balance the horizontal component forces generated during the construction of the V-shaped pier and No. 0 block, and prevent cracks at the root of the V-shaped pier.

Background technique

Prestressed concrete V-shaped piers continuous rigid frame bridges have more reasonable mechanical properties than continuous girder bridges and T-shaped rigid frame bridges. Due to the support of V-shaped piers, the calculation span can be effectively reduced, and the bending moment of the main girder can be reduced. A certain number of beam projects can be reduced, and the V-shaped pier rigid frame bridge has lively lines and beautiful appearance. However, due to the inclination of the pier body, large vertical loads and horizontal loads will be generated during the construction of the pier body, and the requirements for the bearing capacity of the support are relatively high. Currently, the widely used construction methods of the support method and the T-shaped hanger method are only applicable to V-shaped piers with a small volume, and the surrounding geological conditions are required to be good. For large-volume V-shaped piers or geological conditions with weak bearing capacity, the horizontal component force generated by the pier body will cause cracks to appear at the connection between the root of the pier and the cap .

In order to solve the above problems, CN202954299U discloses a kind of "supporting structure for large-angle V-shaped piers and 0# block templates used in continuous rigid frame bridges". To a certain extent, it can resist the horizontal component force generated when the V-shaped pier is poured, but during the construction process, especially when pouring the No. Avoid cracking at the root of the V-shaped pier.

Contents of the invention

The object of the present invention is to address the above problems and provide a V-shaped pier prestressed rod construction method, which can resist the large horizontal component force during the construction of the V-shaped pier and prevent cracks at the root of the V-shaped pier.

Technical scheme of the present invention is as follows:

A V-shaped pier prestressed rod construction method is characterized in that it comprises the following steps:

(1) Set up a set of steel pipe supports on both sides of the V-shaped pier, each set of steel pipe supports is set up with multiple load-bearing beams facing the side of the pier body, and multiple distribution beams are set up on the load-bearing beams along the inclined direction of the pier body. The outer formwork of the pier is supported on the distribution beam, and the pier body reinforcement and inner formwork are installed; 3 layers of tie rods are installed between the formwork on both sides of the pier body, with at least 5 tie rods in each layer, and the first layer of tie rods is set on the V-shaped pier 1/ Below the height of 3, the second layer of tie rods is set above 1/3 of the height of the V-shaped pier and below 2/3 of the height, and the third layer of tie rods is set above 2/3 of the height of the V-shaped pier and below the height of the top, and one end of each tie rod is anchored on The outside of the distribution beam of one group of brackets, and the other end is installed on the outside of the distribution beam of the other group of brackets with a pulling jack;

(2) Pour the pier body concrete in layers, specifically according to the following steps:

(21) Stretch the first layer of tie rods, and pour the pier body concrete to 1/3 of the pier body height;

(22) Stretch the second layer of tie rods, and pour the pier body concrete to 2/3 pier body height;

(23) Stretch the third layer of pull rods and pour the concrete of the pier body to the elevation of the top of the pier body;

When the above-mentioned tie rods of each layer are stretched, they are stretched symmetrically from the middle to both sides, and the tension reaches 20% of the maximum tension value of the tie rods;

(3) Concrete No. 0 on the top of the pier is poured in layers, specifically as follows:

(31) Stretch 3 layers of tie rods sequentially from bottom to top, stretch to 40% of the maximum tension value, and pour No. 0 block bottom slab concrete;

(32) Stretch the 3-layer tie rods sequentially from bottom to top to 60% of the maximum tension value, and pour No. 0 block transverse partition wall and web to 1/2 height;

(33) Stretch 3 layers of tie rods sequentially from bottom to top, stretch to 80% of the maximum tension value, and pour the remaining transverse partition wall and web concrete of No. 0 block;

(34) Stretch 3 layers of pull rods sequentially from bottom to top, stretch to 100% of the maximum tension value, and pour No. 0 block roof concrete;

(35) After the prestressing construction of block No. 0 is completed, remove the tie rods.

In the present invention, three prestressed tie rods are arranged along the height direction in the pier body, and different prestressing forces are applied in different construction stages to achieve the effect of balancing the horizontal component force of the pier body, which can ensure the construction quality and safety of the V-shaped pier body.

Description of drawings

Fig. 1 is the elevation view of support and pull rod arrangement mode of the present invention;

Fig. 2 is a side view of the layout of the tie rods of the present invention;

Fig. 3 is a flowchart of the tie rod construction method of the present invention.

Detailed ways

The specific embodiment of the present invention is as follows:

Step 1. Bracket and pull rod setting: As shown in Figure 1 and Figure 2, a set of steel pipe supports 1 are erected on both sides of the V-shaped pier 10, and each set of steel pipe supports faces the side of the pier body and sets up multiple load-bearing beams 2 in the direction of the bridge. , set up multiple distribution beams 3 along the inclined direction of the pier body on the load-bearing beam, support the outer formwork 4 of the V-shaped pier on the distribution beam, and install the pier body reinforcement and inner formwork 5; install three layers of tie rods between the formwork on both sides of the pier body 6. At least 5 tie rods for each layer, among which the first layer of tie rods is set below 1/3 of the height of the V-shaped pier, the second layer of tie rods is set above 1/3 of the height of the V-shaped pier and below 2/3 of the height, and the third layer of tie rods Set above the 2/3 height of the V-shaped pier and below the height of the top, one end of each pull rod is anchored on the outside of the distribution beam of one group of supports, and the other end is installed on the outside of the distribution beam of another group of supports.

Step 2. As shown in Figure 3, pour the V-shaped pier 10 pier body concrete: the pier body concrete is poured in layers, and each layer is equipped with 6 tension rods. The specific steps are as follows:

(1) Stretch the tie rods of the first layer, and pour the concrete of the pier body to 1/3 of the height of the pier body;

(2) Stretch the second layer of tie rods and pour the pier body concrete to 2/3 of the height of the pier body;

(2) Stretch the tie rods of the third layer, and pour the concrete of the pier body to the elevation of the top of the pier body.

When the above-mentioned tie rods of each layer are stretched, they are stretched symmetrically from the middle to both sides, and the tension reaches 20% of the maximum tension value of the tie rods;

Step 3. As shown in Figure 3, pour the concrete of No. 0 block 20 on the top of the pier: adopt layered pouring, each layer is equipped with 6 tension rods, and the specific steps are as follows:

(1) Stretch the 3-layer tie rods sequentially from bottom to top to 40% of the maximum tension value, and pour the No. 0 bottom slab concrete;

(2) Stretch the 3-layer tie rods sequentially from bottom to top to 60% of the maximum tension value, and pour the No. 0 block transverse partition wall and web to 1/2 height;

(3) Stretch the 3-layer tie rods sequentially from bottom to top to 80% of the maximum tension value, and pour the remaining transverse partition wall and web concrete of Block 0;

(4) Stretch 3 layers of tie rods sequentially from bottom to top to 100% of the maximum tension value, and pour No. 0 block roof concrete;

(5) After the prestressing construction of No. 0 block is completed, remove the tie rods.

Claims (1)

1. The construction method of the V-shaped pier prestress pull rod is characterized by comprising the following steps of:

(1) Respectively erecting a group of steel pipe brackets on two sides of the V-shaped pier, erecting a plurality of spandrel girders in the transverse bridge direction of one side of the pier body of each group of steel pipe brackets, erecting a plurality of distribution beams on the spandrel girders along the oblique direction of the pier body, supporting an outer template of the V-shaped pier on the distribution beams, and installing pier body steel bars and an inner template; 3 layers of pull rods are arranged between templates on two sides of the pier body in a penetrating way, wherein each layer of pull rods is at least 5, the first layer of pull rods is arranged below 1/3 of the height of the V-shaped pier, the second layer of pull rods is arranged above 1/3 of the height of the V-shaped pier and below 2/3 of the height of the V-shaped pier, the third layer of pull rods is arranged above 2/3 of the height of the V-shaped pier and below the height of the top of the V-shaped pier, one end of each pull rod is anchored outside a distributing beam of one group of brackets, and the other end of each pull rod is provided with a tensioning jack outside the distributing beam of the other group of brackets;

(2) The pier body concrete is poured in layers, and the concrete pouring method specifically comprises the following steps:

(21) Stretching the first layer of pull rod, and pouring pier body concrete to 1/3 of the pier body height;

(22) Stretching the second layer of pull rod, and pouring pier body concrete to 2/3 of the pier body height;

(23) Stretching the third layer of pull rod, and pouring pier body concrete to the pier body top elevation;

when each layer of pull rod is stretched, the pull rods are stretched symmetrically from the middle to the two sides, and the stretching is performed until the maximum stretching value of the pull rods is 20%;

(3) The pier top No. 0 block concrete is poured in layers, and the concrete is specifically prepared according to the following steps:

(31) Sequentially tensioning 3 layers of pull rods from bottom to top until the maximum tensioning value reaches 40%, and pouring No. 0 bottom plate concrete;

(32) Sequentially tensioning 3 layers of pull rods from bottom to top to reach 60% of the maximum tensioning value, and pouring a No. 0 transverse partition wall and a web to 1/2 height;

(33) Sequentially tensioning 3 layers of pull rods from bottom to top to 80% of the maximum tensioning value, and pouring the residual diaphragm wall and web concrete of the No. 0 block;

(34) Sequentially tensioning 3 layers of pull rods from bottom to top until the maximum tensioning value is 100%, and pouring No. 0 roof concrete;

(35) And after the prestress construction of the No. 0 block is finished, the pull rod is dismantled.