Experimental Study On Self Repairing Technology Of Cracks In Concrete

Inspired by the mechanism of post-traumatic recovery of the skeleton of the biological world,related scholars have proposed the concept of self-repairing concrete:the self-healing of cracks is achieved by the method of compounding the adhesive,the storage container and the concrete matrix.In this paper,starting from the theory of concrete self-repairing,C30 concrete is used as the substrate of the system,and a repair system consisting of a hollow glass carrier with a built-in adhesive and a substrate is experimentally studied,and the following tasks are completed:1.Based on the microscopic prediction model of concrete effective strength and the theory of composite materials,hollow glass spheres and hollow glass tubes are pre-selected as storage containers.Through experimental comparison,it is found that spherical glass materials are difficult to break in the entire system.Taking into account the ease of breakage and the storage and release of multi-component adhesives,it was further determined that double-tube hollow glass should be used for storage containers.2.The critical volume rate theory is applied and the working mechanism of the glass tube in the concrete is studied based on the equilibrium state of the differential element of the hollow glass tube,and the suitable volume rate,length and wall thickness of the buried glass tube are determined.3.The effect of the glass container on the strength of the concrete matrix is twofold.The flexural strength loss rate is defined to study the repair system.4.According to the working mechanism of the self-repairing concrete,it is determined to select an epoxy resin adhesive with multi-component characteristics,based on the adhesive strength,orthogonal test is used to determine the optimum ratio,and the liquidity is measured by a six-speed rotational viscometer.Were studied.Initially determined the ratio of epoxy resin,692 reactive diluent,650 low-molecular polyamide curing agent and acetone: 100:15:100:30.5.Using C30 concrete as the base material,built-in glass double pipe,using a multi-component epoxy resin adhesive to conduct a three-point bending test of the entire repair system,by analyzing the adhesive outflow condition and the damage of the adhesive surface of the crack and record the resistance Folding strength and other data verify the self-healing effect.