Design and construction method for improving the force transmission of interface between old and new concrete

Abstract

The invention discloses a design and construction method for improving the force transmission of an interface between old and new concrete. The design and construction method comprises the following steps of (1) cutting a groove in a new and old concrete bonding surface of an existing concrete member; (2) chiseling the groove; (3) bundling steel bars of a new concrete member and constructing a pouring formwork, wherein the pouring formwork surrounds a groove opening of the groove; (4) smashing the new concrete member into the pouring formwork; (5) after the concrete reaches the strength, the pouring formwork is removed, that is, the new concrete member is added to the existing concrete member. According to the method, the groove is cut in the new and old concrete bonding surface of the existing concrete member and smashing the new concrete member, due to the fact that the groove is partially stressed to provide most mechanical engagement force required by the new and old concrete bonding surface, mechanical interface forces such as the mechanical engagement forces and Van der Waals' forces of the new and old concrete bonding surface can be greatly increased, control of constructionquality is facilitated, and the ultimate bearing capacity of the new and old concrete bonding surface is improved.

Description

technical field [0001] The invention relates to a design and construction method for improving force transmission at the interface between old and new concrete. Background technique [0002] Concrete structure is the most common structural form in industrial and civil buildings in our country. Concrete reinforcement has been gradually carried out since the 1950s. Appropriate reinforcement techniques and practices ensure the safety of existing building structures and prolong their service life. In concrete reinforcement methods, the handover treatment of new and old concrete is one of the most common reinforcement methods. It is common to add new beams and new slabs to existing concrete columns; add new beams and new slabs to existing concrete concrete walls; add new beams and new slabs to existing concrete beams, etc. [0003] like figure 1 , 2 As shown, the conventional new and old concrete bonding surface treatment is chiseling treatment, that is, chiseling 4 on the ne...

AI Technical Summary

Problems solved by technology

[0004] ⑴At present, there are no clear regulations on the chiseling depth and chiseling rate of most new and old concrete bonding surfaces in engineering, so that the chiseling quality is uneven during actual construction, which brings unsafe factors to the reinforcement quality

[0005] (2) According to the research on the bonding mechanism of old and new concrete in recent years, it is known that the bonding strength of the new and old concrete joint surface is much lower than the strength of the old and new concrete body, which is about 0.4 times that of the complete cast-in-place component. Therefore, when the old and new concrete interface is under excessive load , prone to direct shear damage

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