含Ⅰ型裂纹的普通混凝土梁断裂特性试验研究

通过三点弯曲梁试验方法,采用电阻法测定混凝土梁的起裂、失稳荷载,分别对不同尺寸、不同预制裂缝的普通混凝土梁进行断裂试验研究。结合双K断裂韧度计算方法,计算不同尺寸混凝土三点弯曲梁试件的起裂韧度和失稳韧度。分析研究缝高比及梁高对起裂和失稳韧度、断裂能等断裂参数的影响。试验结果表明:试件的初始缝高比及梁高对混凝土的起裂荷载、失稳荷载、断裂韧度均有一定程度的影响。

Experimental Study on Fracture Characteristics of Plain Concrete Beams with Type I Cracks

In this paper, the method of three point bending beam test is adopted to measure the crack initiation and buckling load of concrete beams by the resistance method. The fracture tests of ordinary concrete beams of different sizes and different cracks are carried out. According to the calculation method of double K fracture toughness, the crack initiation toughness and buckling toughness of three point bending specimens of concrete of different sizes are calculated. The effects of joint ratio and beam height on fracture parameters such as initiation and instability toughness and fracture energy are analyzed and studied. The test results show that the initial joint height ratio and the beam height have some influence on the initiation load, the instability load and the fracture toughness of the concrete.