惰性浆性能优化及固结时变规律试验研究  

Experimental study on performance optimization of inert slurry and time-varying law of consolidation

作　　者：闵凡路 宋帮红[2] 袁大军 陈健[3] MIN Fanlu;SONG Banghong;YUAN Dajun;CHEN Jian(College of Civil Engineering,Beijing Jiaotong University,Beijing 100044,China;College of Civil and Transportation Engineering,Hohai University,Nanjing 210024,China;China Railway 14th Construction Bureau Co.,Ltd.,Jinan 250014,China)

机构地区：[1]北京交通大学土木建筑工程学院,北京100044 [2]河海大学土木与交通学院,江苏南京210024 [3]中铁十四局集团有限公司,山东济南250014

出　　处：《混凝土》2024年第6期6-11,共6页Concrete

基　　金：国家自然科学基金(52078189)。

摘　　要：针对富水粉细砂地层中由于惰性浆凝结时间长,早期强度低等引起的地层沉降及管片上浮控制难题,开展水泥改性惰性浆配制及固结试验研究,结果表明:随水泥掺量从0增加到40 kg/m^(3),浆体凝结时间从24 h缩短到14 h,3 d强度从35 kPa提高到180 kPa,显著缩短浆体凝结时间,提高早期强度,但同时降低了浆体流动性。另外,在不掺加水泥时,聚羧酸减水剂对惰性浆性能影响不大,而在掺加水泥后,聚羧酸减水剂能提高浆体流动性能,延缓凝结时间,提高强度。水泥掺量从0增加到30 kg/m^(3),浆体渗透系数降低,进而降低固结排水速率,延长孔隙水压力消散时间,减小固结排水量,使固结轴向应变减小。在同一水泥掺量下,增大固结压力提升了固结排水量,使浆体水胶比降低,无侧限抗压强度提高。Aiming at the problems of formation subsidence and segment floating control caused by the long setting time and low early strength of inert slurry in water-rich silty-fine sand strata,the preparation and consolidation test of cement-modified inert slurry was carried out.The results show that with the increase of cement content from 0 to 40 kg/m^(3),the setting time of the slurry is shortened from 24 h to 14 h,and the 3 d strength is increased from 35 kPa to 180 kPa,which significantly shortens the setting time of the slurry and improves the early strength.But at the same time,the fluidity of the slurry is reduced.In addition,when no cement is added,the polycarboxylate superplasticizer has no effect on the properties of the inert slurry,but after adding cement,the polycarboxylate superplasticizer can improve the fluidity of the slurry,delay the setting time,and improve the strength.When the cement content increases from 0 to 30 kg/m^(3),the permeability coefficient of the slurry decreases,which in turn reduces the consolidation drainage rate,prolongs the pore water pressure dissipation time,reduces the consolidation drainage volume,and reduces the consolidation axial strain.Under the same cement content,increasing the consolidation pressure increases the consolidation drainage,reduces the water-binder ratio of the slurry,and increases the unconfined compressive strength.

关 键 词：惰性浆 流动度 凝结时间 水泥改性 渗透系数 固结 

分 类 号：TU528.01[建筑科学—建筑技术科学]