基于水灰比指数的水泥土无侧限抗压强度

Unconfined compressive strength of cement-solidified soil based on water-cement ratio index

为解决水泥土无侧限抗压强度归一化问题,提出了水灰比指数的概念,通过室内水泥土无侧限抗压强度试验,分析了无侧限抗压强度与水灰比指数的关系,水泥土固化系数与龄期的关系,建立了基于14 d龄期水灰比指数的水泥土强度预测公式,并结合已有学者的试验数据对预测公式进行了验证。另外,还探讨了添加外加剂时水泥固化土实测值与预测值的关系。试验结果表明:水泥土无侧限抗压强度与其水灰比指数的倒数呈线性递增关系;标准固化系数与龄期的自然对数满足指数增长规律;提出的水泥土强度预测公式较好地适用于水泥加固土90 d龄期内的无侧限抗压强度预测,但不适用于掺Ca(OH)_(2)、KCl、CaCl_(2)外加剂的水泥固化土强度预测。

To solve the problem of normalization of unconfined compressive strength of cement-solidified soil,the concept of water-cement ratio index was presented.Through indoor unconfined compressive strength test of cement-solidified soil,the relationship between unconfined compressive strength and water-cement ratio index and the relationship between curing coefficient and curing age of cement-solidified soil were analyzed.A formula to predict the strength of cement-solidified soil based on the water-cement ratio index of 14 days was established,and verified by the available experimental data by scholars.In addition,the relationship between the measured value and the predicted value of cement-solidified soil with additives was also discussed.The results show that the unconfined compressive strength of cement-solidified soil increases linearly with the reciprocal of water-cement ratio index and the standard curing coefficient and natural logarithm of curing age meet the law of exponential growth.The proposed formula for predicting the strength of cement-solidified soil is better suitable for the prediction of unconfined compressive strength of cement-solidified soil of 90 days,but not suitable for the prediction of the strength of cement-solidified soil mixed with Ca(OH)_(2),KCl and CaCl_(2).