上海水泥固化黏土的强度与硬度相关性研究

Relationship between Strength and Hardness of the Cement Treated Shanghai Clayey Soil

现场施工过程中,往往需要对水泥固化土的无侧限抗压强度进行快速检测。针对目前水泥固化黏土无侧限抗压强度检测中存在的操作不简便、试验时间长、测试费用高等缺点,提出通过水泥土硬度估计强度的方法,对现场水泥土强度进行快速检测。本文以上海地区黏性土为研究对象,对上海地区水泥固化黏土强度与硬度的相关性进行了试验研究;探讨了加固土的硬度与养护时间、水泥掺量以及强度与硬度之间的关系。试验结果表明:上海黏土水泥土强度和硬度呈正比相关,对数坐标下的强度和硬度有着形如lnqu=ap+b的线性关系。养护初期,硬度增长速度大于水泥土强度增长速度。养护后期,强度增速大于硬度增速。

Unconfined compression strength of cemented-soil often needs to be determined in the construction sites. But the common unconfined compression strength test methods have the disadvantage of inconvenient operation, long test duration and high cost. For quick test of unconfined compression strength, a new method by determining the hardness of cement soil to estimate the unconfined compression strength is proposed. Laboratory tests are conducted to study the relationship between hardness and curing time, cement content, unconfined compression strength of Shang- hai clay. The results show that the unconfined compression strength qu is proportional to the hardness （ p ） of Shanghai clay. And they have the linear relationship lnqu = ap ＋ b. In the early curing period, the growth rate of hardness is larger than the rate of unconfined compression strength. But in the late curing period, it＇ s the opposite.