Grouting connection construction method

Abstract

The invention discloses a grouting connection construction method which is used for connecting vertical reinforcements of an assembled concrete structure. The grouting connection construction method includes the steps: firstly, embedding a plurality of grouting connection devices at one end of a precast concrete unit to be connected in advance; secondly, lifting the precast concrete unit and then manufacturing a grouting box dam; thirdly, grouting horizontal gaps and then grouting the grouting connection devices. The grouting connection devices are connected with connection reinforcements extending out of a lower unit. Plugging grouting of the horizontal gaps and grouting of the grouting connection devices can be performed within the same day, so that the mounting efficiency of the precast concrete unit is greatly improved, the grouting connection construction method can be implemented in a subzero temperature environment even in winter, construction difficulty is reduced, and working efficiency is improved.

Description

technical field [0001] The invention relates to the technical field of connection construction of prefabricated concrete components of prefabricated concrete structures, in particular to a construction method for vertical reinforcement connection of prefabricated concrete structures. Background technique [0002] At present, two methods are usually used for the vertical reinforcement grouting connection construction of prefabricated concrete structures. 1. The pressure grouting method of the Unicom cavity: after the prefabricated components are installed in place, they are separated from the lower components by spacers. After the circumference of the horizontal joint is closed with sealing material, the horizontal joint is used as a connecting grouting cavity, and the grouting hole is poured into the horizontal joint from a steel grouting connection device or a grouting hole reserved on the sealing material of the horizontal joint circle Cement-based grouting materials are u...

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Problems solved by technology

[0003] The first type of pressure grouting in the connecting cavity is difficult to overcome the grout leakage problem during grouting. The connecting cavity is a closed structure and pressure grouting must be used. If the seal around the horizontal joint is not tight or the sealing material is insufficient in pressure resistance, the problem of grout leakage will occur. Once connected Grout leakage in the cavity directly affects the filling degree of the grouting material in the steel grouting joint, and affects the quality of the steel grouting connection of the prefabricated component. The main reasons are: 1. Assembled concrete shear wall structure, the lower component connected by the prefabricated shear wall component For the cast-in-place concrete slab, the high points on the surface of the cast-in-place concrete slab are difficult to be on the same level, so the prefabricated shear wall components are installed on this surface, and after the bottom surface is adjusted to the level, the upper surface of the cast-in-place slab and the prefabricated shear wall The height of the gap between the lower end faces of the force wall components is inconsistent. Therefore, when the horizontal seam is sealed with elastic rubber strips, PE rods or sponge strips, the lower end face of the prefabricated shear wall above will press it against the concrete surface below. When the frictional force on the surface of the concrete structure is sealed, when the grouting material is poured into the steel grouting connection device, and the grouting pressure reaches a high level, the grouting material will push the above-mentioned sealing material and the place where the frictional force of the concrete surface is small and leak out. , resulting in quality problems of steel grouting connections and potential safety hazards

After the grout leakage problem was found, grouting and other treatment measures had to be taken, but the work efficiency was very low, which affected the construction progress of the structure; when the horizontal joints were sealed with special cement base slurry, although the sealing effect and reliability It has been greatly improved, but it takes a long time to wait for the sealing material to harden and reach the working strength, so it also has a great impact on the construction speed of structure installation; The gap between the upper surface of the poured concrete and the lower surface of the prefabricated column is the same as that of the prefabricated shear wall structure. The gap height of the horizontal joints is uneven. When the cross-sectional size of the structural column does not exceed 100cm×100cm, the horizontal joint grouting connection cavity is usually not divided. However, the area of ​​the connected grouting cavity at the bottom is mostly larger than the maximum area allowed by the connected grouting cavity of the shear wall, and the grouting pressure is high. Once the grouting material breaks through any part of the surrounding sealing zone If the grouting of the prefabricated column fails, the sealed seat grout must be opened, all the grouting material filled in must be washed out, and then re-sealed and grouted, which greatly affects the construction efficiency; for larger prefabricated structural columns, separate Multiple grouting interconnected cavities are made in the warehouse method, which also has high requirements for horizontal sealing and separate warehouses, and the workload is large and the construction cost is high.

In short, although the grouting construction of the Unicom cavity can be grouted to connect multiple connecting devices at one time, it has high requirements for sealing materials and sealing methods. It is also a severe test for the management and personnel quality of construction in my country. It not only affects the overall construction efficiency, but also the difficult-to-handle grout leakage connection structure will cause quality problems

[0004] The second type of seat grouting method has problems of low work efficiency and the gap at the bottom of the component: 1. Work efficiency problems, because the seat grout method is to pile up plastic dry and hard seat slurry or pour fluid seat slurry, and then install For prefabricated components, the dry and hard seat slurry should remain plastic before the component is installed, and the fluid seat slurry should remain flowable and cannot be solidified or hardened. Therefore, the construction of the seat slurry must cooperate well with the hoisting work of the prefabricated component, that is, mixing and The grouting construction must be carried out in conjunction with the hoisting time of the components. The grouting construction is restricted by the lifting of the components, and the work efficiency is low, which does not meet the characteristics of fast construction and high work efficiency of modern prefabricated structures; It is extremely difficult to keep the bottom surface of the component parallel to the horizontal plane and sit on the seat slurry. Therefore, for the dry hard seat slurry, after the component sits on the seat slurry, adjust the prefabricated component to make the bottom surface parallel to the horizontal plane, while The dry hard seat slurry cannot flow. Once such an adjustment is made, there will inevitably be a gap between the lower surface of the component and the upper surface of the shaped seat slurry; for the fluid seat slurry, when the component falls to the surface of the seat slurry, the falling speed is faster The air in the chiseling at the bottom of the component or the hollow on the exposed surface cannot be fully discharged, so that local pockets of air may appear on the bottom surface. If the falling speed of the component is carefully controlled when it contacts the seat slurry, the installation speed of the component will inevitably be affected. Therefore, the seat slurry grouting construction with low work efficiency, and there is a quality risk of gaps or pockets between the bottom of the component and the seat grout layer

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