（湖南大学土木工程学院， 长沙 410082）

［摘要］《建筑砂浆基本性能试验方法标准》（JGJ/T 70—2009）对建筑砂浆立方体抗压强度试验中的底模作了重大的修改，为了协调和统一各规范对砂浆试块底模的规定及砂浆强度的取值，总结了现有规范对砂浆试块底模的规定，分析了其中存在的问题以及对实际工程产生的不利影响；根据底模的自身特性及底模与砂浆试块间的相互作用，总结并分析了不同因素对砂浆试块抗压强度的影响。基于不同块材底模与钢底模砂浆试块抗压强度比值的频数分布，采用合理的保证率，按正态分布分析，提出了各类砌体块材作底模时，砂浆强度的合理取值方法。

［关键词］建筑砂浆； 抗压强度； 规范； 底模； 取值方法

中图分类号：TU522-3文献标识码：A文章编号：1002-848X(2019)08-0108-07

Research on the influences of different bottom dies to the compressive strength of the mortar specimen

Chen Dachuan, Wang Dingwei, Shi Chuxian

（College of Civil Engineering, Hunan University, Changsha 410082, China）

Abstract:Standard for test method of performance on building mortar (JGJ/T 70—2009)has been made major changes on the problem of bottom die in the clauses of the cube compressive strength of construction mortar. In order to coordinate and unify the stipulations about the bottom die of mortar specimen in specification and the mortar strength values, the stipulations about the bottom die of mortar specimen in the existing specifications were summarized and  the existing problems and the bad impacts to the real projects were analyzed. According to the characteristics of the bottom die and the interaction between bottom die and the mortar specimen, the influences of different factors on the compressive strength of mortar specimen were summarized and analyzed. In view of the frequency distribution of the compressive strength ratio of the mortar specimen between different bottom dies and steel bottom die, using a reasonable guarantee rate, according to the normal distribution analysis, a reasonable method for determining the strength of the mortar when various types of masonry blocks are used as the bottom die was proposed.

Keywords:construction mortar; compressive strength; specification; bottom die; value method

*国家自然科学基金资助项目（50778067）。

作者简介：陈大川,博士, 教授,Email: 13707311929@163.com。