Through the three-point bending test on 50 specimens of steel fiber reinforced high strength concrete (SFHSC) with the size of 100 mm×100 mm×515 mm, the effect of the fiber volume fraction (ρf) upon the effective crack length (al) fracture toughness (KⅠc) and critical crack opening displacement (δc) of high strength concrete (HSC) was studied.
通过50个尺寸为100mm×100mm×515mm的钢纤维高强混凝土切口梁三点弯曲试验,研究钢纤维体积率对高强混凝土有效裂缝长度、断裂韧度和临界裂缝张开位移的影响。
With Young\'s modulus and the stress at the effective crack tip as two only prerequisites, the model can predict the maximum load and its corresponding effective crack length, and in turn the fracture toughness of concrete specimen under compact tension.
以混凝土的弹性模量和有效裂缝长度尖端的应力为两个基本参数,可推导出紧凑拉伸试件的极限承载力以及临界有效裂缝长度,进而求得混凝土的断裂韧度。
And the fracture parameters such as efficient crack length(aeff),critical stress intensity factor(KsIC) and crack tip open displacement(CTOD) were obtained through theoretical calculation.
通过对带有切口的砂浆试样进行三点弯曲试验测试,得到了掺量为0—18%的SBR(styrene-butadiene rubber,简称SBR)乳液改性水泥砂浆荷载-变形曲线及相应裂缝嘴张开位移(CMOD),并通过理论计算得到了不同掺量下改性水泥砂浆的有效裂纹长度(aeff)、临界应力强度因子(KsIC)及裂纹尖端张开位移(CTOD)等断裂特征参数。
According to the double K fracture criterion,the critical effective crack length ac and stress intensity factors ofⅠ-Ⅱ mixed-mode fracture specimens are calculated based on the data of the experiment done before and the data of present numerical simulation experiment.
根据以前的混凝土Ⅰ-Ⅱ复合型断裂实验资料,同时采用数值模拟实验的方法,基于双K断裂准则,分别计算了混凝土Ⅰ-Ⅱ复合型断裂试件失稳断裂破坏时,断裂过程区影响的临界有效裂缝长度ac及应力强度因子KⅠ、KⅡ。
From the data of concrete fracture tests in china recently,fracture toughness KⅠc calculated with the critical effective crack length ac is not size-independent.
从国内一些单位近来所进行的断裂试验数据看,虽然在计算断裂韧度KⅠc时,裂缝长度a的取值为已经考虑了断裂过程区影响的临界有效裂缝长度ac,但KⅠc仍是有尺寸效应的,且基本满足由Weibull脆性破坏统计理论所导出的尺寸效应关系式,严格地说,此尺寸效应关系式只能在包括缝高比a/h在内的所有几何尺寸均相似的条件下才能应用。