机场道面钻芯劈裂强度的尺寸效应系数

通过对比相同配合比下的室内标准模制圆柱体混凝土试样与现场试验板钻芯标准芯样之间的劈裂强度,探讨了钻芯取样测试对劈裂强度的影响;通过对不同长度芯样的劈裂强度进行对比,研究了试样长度对芯样劈裂强度的影响规律。结果表明:由于钻芯过程产生的损伤及试验板与模制圆柱体试件的混凝土拌和、振捣、养护条件不同,导致钻芯法测得的混凝土劈裂强度相比室内试验降低15.7%;另外由于圆柱体试件的长度增加,混凝土试件的受力平面也随之增大,平面内存在的微裂缝、微孔洞的数量也会随之增多,导致随着试样长度的减小,测得的试样劈裂强度逐渐增大。最终得出国内某通用机场新建飞行区工程的劈裂强度与长度的修正系数。

Size Effect Coefficient of Core Splitting Strength of Airport Pavement

By comparing the splitting strength between the laboratory standard molding cylindrical concrete specimen and the field test plate core standard core sample under the same mix proportion,this paper discusses the influence of core sampling test on the splitting strength.By comparing the splitting strengths of the different lengths of core samples,this paper studies the influence rule of sample length on the splitting strength of core sample.The results show that the splitting strength of concrete measured by the drill core method is 15.7%lower than the laboratory test because of the damage caused by the drill core process and the difference of concrete mixing,vibrating and curing conditions between the test plate and the molded cylinder specimen.In addition,as the length of the cylinder specimen increases,the stress plane of the concrete specimen also increases,and the number of micro-cracks and micro-holes in the plane also increases.As a result,as the length of the specimen decreases,the splitting strength of the measured specimen increases gradually.Finally,the correction coefficients of splitting strength and length of a new flying zone project at a general airport in China are obtained.