The cement concrete pavement in the eastern section of the Shenshan Expressway is seriously damaged. The repair method is a comprehensive treatment of grouting and chemicaling rebar reinforcement, that is, grouting to stabilize the slab first to deal with the void at the bottom of the slab. Then the concrete slab is connected by the method of chemicaling reinforcement, that is, the connecting reinforcement of 25 is imchemicaled with modified epoxy resin through drilling inclined holes (see Figure). The spacing of chemicaling bars is 50cm, and the inclined holes are arranged in a cross.

Construction method

1 pay off

Before starting the drilling construction, the structural surface must be cleaned up, and the technicians will set out the lines to indicate the drilling positions of the anchorage points of the steel bars. After the drilling position is checked and marked, the person in charge of the site will check the line.

2 drilling

When drilling, the construction should be carried out in strict accordance with the design requirements. Since it is an oblique drilling, pay attention to the force direction of the drill pipe to prevent the drill pipe from breaking. After drilling, clean the surrounding dust, use an air pump and a brush to clean the hole. After cleaning, make the inside of the hole clean and dry. Use clean cotton to seal the cleaned holes tightly to prevent dust and foreign objects from falling into them.

3 Grouting Anchorage

The strength of the adhesive is the key to the chemicaling bar technology. The anchoring properties of the anchoring glue used for chemical chemicaling should be determined through special tests. Anchoring glue can be divided into three types: tube type, mechanical injection type and on-site preparation type according to the different forms of use. Modified epoxy resin is used in this project.

This project uses self-prepared modified epoxy resin. Fill people from the orifice, and the filling in the hole shall prevail. Then insert the steel bar into the hole, and rotate slowly in the same direction while inserting it until it passes through the bottom of the hole. At this time, epoxy resin should overflow from the hole.

Repair cracks

First, gouge out the loose parts on both sides of the seam along the crack and blow it clean. Then, in the case of dryness, use diluent asphalt (emulsified asphalt) to coat and sweep the seam. Then use asphalt mixture, asphalt fried sand into fine material or asphalt concrete to fill and compact, the surface is flattened with a soldering iron, and finally covered with a thin layer of medium sand. Finally, when there is no other deformation, the construction surface can be removed and repaired with epoxy resin mortar.