CN106968400A - One kind removes unbonded prestressed concrete structure moveable anchor and its application method - Google Patents

Abstract

The invention discloses a tool anchor for dismantling unbonded prestressed concrete structures and a method for using the same, belonging to the field of civil engineering, used for dismantling unbonded prestressed concrete structures, and solving the problem of dismantling unbonded prestressed concrete structures The problem of poor security. The tool anchor for dismantling unbonded prestressed concrete structures consists of three parts: an anchor cup with a special-shaped notch, a special-shaped block, and a matching clip. Method: At the beginning of dismantling the unbonded prestressed concrete structure, remove the concrete surrounding the unbonded reinforcement within a range of no less than 120mm away from the working anchor at the anchorage end on one side with a net distance of about 1.0m; peel off the unbonded reinforcement sheath, Surround the prestressed tendon with an anchor cup with a special-shaped notch, insert a supporting clip between the prestressed tendon and the inner wall of the anchor cup, push the special-shaped plug into the notch of the cup wall, and tap the supporting clip with a small hammer to make it fit between the prestressed tendon and the inner wall of the anchor cup. The inner walls of the anchor cups are in a plugged state; remove the working anchor on the other side, and then carry out subsequent dismantling work.

Description

A tool anchor for dismantling unbonded prestressed concrete structures and its application method

technical field

The invention belongs to the field of civil engineering, and in particular relates to a tool anchor for removing unbonded prestressed concrete structures and a method for using the same.

Background technique

The unbonded prestressed concrete structure refers to the concrete structure in which the unbonded prestressed tendons are reasonably arranged and anchored in the structural members. The prestress of the unbonded tendons is maintained by the reliable anchorage of the anchors at both ends.

Due to the adjustment of urban planning and the failure of project quality to meet the requirements, it is sometimes necessary to demolish the unbonded prestressed concrete structure. The unbonded prestressed tendons have accumulated a large amount of tensile strain energy. Once one side of the anchorage is removed, the unbonded tendons will fly out like arrows, causing casualties and property losses. In order to ensure the safety of the demolition of unbonded prestressed concrete structures, tool anchors for demolition of unbonded prestressed concrete structures were developed.

Contents of the invention

The invention is a tool anchor for dismantling unbonded prestressed concrete structures, which aims to solve the problem of removing one side of the anchor when unbonded prestressed concrete structures are removed, and unbonded tendons may fly out causing casualties and property The problem of loss.

A tool anchor for dismantling unbonded prestressed concrete structures is composed of three parts: an anchor cup with a special-shaped notch, a special-shaped block, and a matching clip. The anchor cup is equipped with the same central taper hole as the conventional anchor, and the cup wall has a special-shaped gap with a wide inside and a narrow outside, a near wide and far narrow, and the minimum width of the gap is not less than the nominal diameter of the unbonded rib. The shape and size of the special-shaped plug coincide with the notch of the anchor cup, that is, to prevent the plug from being squeezed out by the clip when the non-adhesive ribs shrink inward, and not to slide out along the longitudinal direction, the plug is designed to be wide inside and narrow outside , Near wide and far narrow.

At the beginning of dismantling the unbonded prestressed concrete structure, remove the concrete surrounding the unbonded reinforcement within a range of not less than 120mm away from the working anchor at the anchorage end on one side with a net distance of about 1.0m, peel off the unbonded reinforcement sheath, and use The anchor cup with special-shaped notch surrounds the prestressed tendon, insert the supporting clip between the prestressed tendon and the inner wall of the anchor cup, push the plug into the gap of the cup wall, and finally hit the clip with a small hammer to make it fit between the prestressed tendon and the inner wall of the anchor cup. between is in a tight state. After the above work is completed, remove the working anchor on the other side, and then carry out subsequent demolition work. It needs to be pointed out here that the requirement of a clear distance of about 1.0m between the tool anchor used for dismantling and the working anchor at the anchoring end is to meet two conditions: one is to remove the tensile strain of the prestressed tendon when the working anchor at the anchoring end on the other side is removed The concrete between the tool anchor and the working anchor can not be destroyed; the second is to cut off the prestressed tendon between the tool anchor and the working anchor, and the tensile strain energy of the prestressed tendon between the two is not enough to make the unbonded tendon fly out.

Beneficial effects of the present invention:

When the present invention is used to dismantle the unbonded prestressed concrete structure, after one side of the working anchor is removed, the unbonded tendons that have lost the prestress will be re-anchored by the newly installed tool anchors and will not fly out.

Description of drawings

Fig. 1 is the structural schematic diagram of tool anchor for removing unbonded prestressed concrete structure;

Fig. 2 is the schematic structural view of the anchor cup with a special-shaped notch;

Fig. 3 is the front view of the anchor cup with a special-shaped notch;

Fig. 4 is the top view of the anchor cup with a special-shaped notch;

Fig. 5 is the structural representation of described special-shaped block;

Fig. 6 is the front view of described special-shaped block;

Fig. 7 is a top view of the special-shaped block.

In the figure: 1. An anchor cup with a special-shaped notch; 2. A special-shaped plug; 3. A supporting clip.

detailed description

Specific embodiment 1: This embodiment will be described in detail with reference to Figures 1 to 7. In this embodiment, a tool anchor for dismantling unbonded prestressed concrete structures consists of an anchor cup 1 with a special-shaped notch, a special-shaped plug 2, and a matching clip 3 It consists of three parts.

Embodiment 2: This embodiment differs from Embodiment 1 in that the anchor cup 1 with a special-shaped notch is provided with the same central taper hole as the conventional scale anchorage, and the cup wall is wide inside and narrow outside, near wide and far narrow The minimum width of the notch is not less than the nominal diameter of the non-adhesive rib. Others are the same as the first embodiment.

The inner width and outer narrowness, near width and far narrowness mean that the width inside the upper end of the special-shaped notch is greater than the width outside the upper end of the special-shaped notch; the width inside the lower end of the special-shaped notch is greater than the width outside the lower end of the special-shaped notch; The width of the inner side of the lower end; the width of the outer side of the upper end of the special-shaped notch is greater than the width of the lower end of the special-shaped notch.

Embodiment 3: The difference between this embodiment and Embodiment 1 or 2 is that the shape and size of the special-shaped plug 2 coincides with the shape and size of the anchor cup 1 with a special-shaped notch, which is wide inside and narrow outside, and narrow near and far. Others are the same as those in Embodiment 1 or 2.

Specific implementation mode four: a method of using a tool anchor for dismantling an unbonded prestressed concrete structure in this embodiment is specifically carried out in the following steps:

Step 1. At the beginning of dismantling the unbonded prestressed concrete structure, remove the concrete around the unbonded reinforcement within the range of not less than 120mm beyond the net distance of about 1.0m from the working anchor at the anchorage end on one side;

Step 2. Peel off the sheath without bonding ribs in the section of no less than 120mm as described above, and surround the prestressed tendons with the anchor cup 1 with a special-shaped notch;

Step 3: Insert the supporting clip 3 between the prestressed tendon and the inner wall of the anchor cup 1 with the special-shaped gap, push the special-shaped plug 2 into the gap of the cup wall, and tap the supporting clip 3 with a small hammer to make it fit between the prestressed tendon and the anchor cup 1. The inner walls of the cups are in a plugged state; step 4, remove the working anchor at the anchor end on the other side, and then carry out subsequent dismantling work.

Claims (4)

1. A tool anchor for removing unbonded prestressed concrete structures is used to ensure the safety of unbonded prestressed concrete structures. The supporting clip (3) consists of three parts. 2. A tool anchor for removing unbonded prestressed concrete structures according to claim 1, characterized in that the anchor cup (1) with a special-shaped notch is provided with the same central taper hole as the conventional anchor, and the cup wall remains There are special-shaped gaps with inner width and outer narrowness, near width and far narrowness, and the minimum width of the gap is not less than the nominal diameter of the non-adhesive rib. 3. A tool anchor for dismantling unbonded prestressed concrete structures according to claim 1, characterized in that the shape and size of the shaped plug (2) and the anchor cup (1) gap with the shaped notch just match, It is wide inside and narrow outside, near wide and far narrow. 4. a kind of use method of removing unbonded prestressed concrete structure tool anchor as claimed in claim 1, is characterized in that the use method of removing unbonded prestressed concrete structure tool anchor is specifically carried out according to the following steps : Step 1. At the beginning of dismantling the unbonded prestressed concrete structure, remove the concrete around the unbonded reinforcement within the range of not less than 120mm beyond the net distance of about 1.0m from the working anchor at the anchorage end on one side; Step 2, peel off the sheath without bonding tendons in the section of no less than 120mm as described above, and surround the prestressing tendons with the anchor cup (1) with a special-shaped notch; Step 3: Insert the supporting clip (3) between the prestressed tendon and the inner wall of the anchor cup (1) with the special-shaped notch, push the special-shaped plug (2) into the notch of the cup wall, and tap the supporting clip (3) with a small hammer Make it in a tight state between the prestressed tendon and the inner wall of the anchor cup; Step 4: Eliminate the working anchor at the anchor end on the other side, and then carry out the follow-up demolition work.