南京纬三路过江通道弃砂在壁后注浆材料中的利用  

Application of Waste Sand in Backfilling Grouting in Shielding Tunneling:Case Study on Weisanlu River-crossing Tunnel in Nanjing

作　　者：陈喜坤[1] 朱伟[1,2] 王睿[1] 闵凡路[1,2] 魏代伟 

机构地区：[1]河海大学土木与交通学院,江苏南京210098 [2]河海大学岩土力学与堤坝工程教育部重点实验室,江苏南京210098 [3]南京河海科技有限公司,江苏南京210098

出　　处：《隧道建设》2015年第11期1176-1181,共6页Tunnel Construction

基　　金：国家重点基础研究发展计划(973计划)(2015CB057803);国家自然科学基金项目(51408191);江苏省疏浚与泥处理利用国家工程技术研究中心培育点(BM2013013)

摘　　要：为了解决南京纬三路过江通道施工产生的弃砂在壁后注浆浆液中的再利用问题，通过将施工产生的弃砂筛分成细度模数分别为1．652、1．096、0．773的砂，并将其分别用于配置不同水胶比的壁后注浆浆液，探究了砂的细度模数对壁后注浆浆液基本性能的影响，进而提出了弃砂再利用的方法。结果表明：浆液用砂的细度模数越高，浆液的流动度、稠度、泌水率、体积收缩率和凝结时间越长，强度越低；弃砂细度模数筛分为0．75～1．08，水胶比为0．9，可直接作为壁后注浆材料。南京纬三路过江通道弃砂再利用的方案为：将弃砂过1．25 mm 筛后75％替换原浆液用砂，调整水胶比为0．85；或50％替换原浆液用砂，调整水胶比为0．9，2种方案都满足了工程要求，并具有一定的经济效益。A large amount of waste sand is produced in shield tunneling and it is of great importance to study the recycling use of the waste sand in backfilling grouting.In the paper,the waste sand produced in the construction of Weisanlu River-crossing Tunnel in Nanjing is classified into three grades with 1.652,1.096 and 0.773 fineness modulus respectively,backfilling grouts with different water/binder ratios are prepared by using the mentioned waste sand,the influence of the fineness modulus of the sand on the basic properties of the backfilling grout is studied,and suggestion is made on the application of the waste sand in the backfilling grout.Conclusions drawn are as follows：1 ） The higher the fineness modulus of the sand,the larger the fluidity,consistency,bleeding rate,volume shrinkage rate and setting time of the grout,and the lower the strength of the grout;2）Grout prepared with the waste sand of 0.75-1.08 fineness modulus and having 0.9 water/binder ratio can be directly used for backfilling;3）The following two waste sand recycling use schemes can be adopted for Weisanlu River-crossing Tunnel in Nanjing：A）The sand in the original mixing proportion is replaced by the waste sand screened by 1.25 mm sieve,with 75% replacement ratio,and the water/binder ratio is adjusted as 0.85;B）The sand in the original mixing proportion is replaced by the waste sand screened by 1.25 mm sieve,with 50% replacement ratio,and the water/binder ratio is adjusted as 0.9.

关 键 词：南京纬三路过江通道 弃砂 泥水盾构 壁后注浆 细度模数 

分 类 号：U455[建筑科学—桥梁与隧道工程]