基于延迟时间的水泥改良土试验研究及施工工艺优化

Experimental Study and Construction Technology Optimization of Cement⁃improved Soil Based on Delay Time

结合京沈客运专线星火动车所试车线改良土路基结构试验段施工,对水泥改良土击实最大干密度、无侧限抗压强度等与延迟时间的关系进行分析,提出了控制从拌和到碾压成型时间的合理施工过程。结果表明:随着延迟时间的增加,改良土的7 d无侧限抗压强度减小;延迟时间大于等于3 h后随着延迟时间的增加,改良土的最大干密度和压实系数减小。提出了延迟时间不得超过3 h,最佳控制时间为2 h以内的施工工艺。

Based on the construction of improved soil subgrade structure test section of Xinghuo EMU test line on Beijing-Shenyang passenger dedicated railway line,the relationship between the maximum dry density,unconfined compressive strength and delay time of cement-improved soil was analyzed,and the reasonable construction process from mixing to rolling forming time was proposed.The results show that with the increase of delay time,the 7 d unconfined compressive strength of improved soil decreases.When the delay time is greater than or equal to 3 h,the maximum dry density and compaction coefficient decrease with the increase of delay time.It is proposed that the delay time should not exceed 3 h and the best control time should be within 2 h,and the corresponding construction pracess was provided.