拉拔法测试混凝土强度的试验研究

Experiment and research on concrete strength by the pulling and extracting test method

混凝土抗压强度f_c(MPa)与极限拉拔力P(kN)间的线性关系是,f_c=4.51P-9.41,相关系数r=0.98,强度相对标准误差e_r=9.5％。这是本文作者通过拉拔试验得出的结论。在试验过程中,同时考虑了试件不同部位、粗骨料种类、粒径大小、混凝土养护条件、混凝土龄期、混凝土强度等级等因素的影响。本试验在国内首次将拉拔法引入到轻骨料混凝土的强度测试中,并成功地用于普通混凝土及轻混凝土的工程实践,收到了良好的效果。

The linear relationship between f_o(MPa), the concrete compressive strength, and P(kN), the ultimate concrete tensile force, is formulated as f_o = 4.5lP9.41, in which, the corresponding coefficient r=0.98, and the respective error percentage er = 0.95%.Based upon the experiment and research on concrete strength by the pulling and extracting test method, the author has derived and confirmed the aforementioned conclusion.During these tests, it has duly paid attention and considered the various factors concerning concrete strength, such as,(l)the different acting portion of specimen)(2)the kinds and sizes of coarse aggregates;(3)the concrete curing conditions, and(4)the ages of concrete etc.This is the first time ever applied in our country and it has been proved successful in appraising not only the strength of ordinary aggregate concrete but also the strength of light aggregate concrete.