用于填筑狭小地下空间的流态水泥土材料室内试验研究

Laboratory Test on Mixed Cement-soil Material for Filling Narrow Underground Space

用人工拌制的流态水泥土材料填筑狭小的地下空间可以有效解决回填土质量控制难题。对拌制的流态水泥土进行了室内无侧限抗压强度试验和直剪试验,研究了不同水泥掺量、水灰质量比、养护方式、养护时间对水泥土强度的影响,并获取了水泥土材料的变形模量、黏聚力和内摩擦角。用南京典型粉质黏土拌制的水泥土变形模量98.4~112.7 MPa、黏聚力185.54~213.45 kPa、内摩擦角32°~39°,可以有效降低回填区周边的不均匀沉降。

A cement-soil filling material is proposed for the quality problem of backfilling in narrow spaces that commonly exists in the development and utilization of underground spaces.The unconfined compressive strength test and direct shear test were conducted for the mixed fluid cement-soil.The effect of cement content,cement-soil ratio,curing method and curing time on the strength of cement-soil were studied,and the deformation modulus,cohesion and internal friction angle of cement-soil material were obtained.The experimental study shows that the mixed cement-soil has good physical and mechanical indexes.The deformation modulus is 98.4~112.7 MPa,the cohesion is 185.54~213.45 kPa,and the internal friction angle is 32°~39°,which can effectively reduce the surface settlement caused by the quality of backfill construction.