海域环境下泥水盾构同步注浆浆液性能试验研究

Experimental Research on Grout Performance of Synchronous Grouting of Slurry Shield in Marine Environment

盾构掘进同步注浆是控制隧道变形的关键工序,如何确保海水环境下同步注浆性能满足要求是施工必须考虑的问题。以苏埃通道工程盾构隧道为背景,通过浆液对比试验,得到海水拌制的同步厚浆在流动性、凝结时间、抗折强度、抗压强度和固结收缩率指标上均优于淡水拌制的同步厚浆;开展了海域环境下浆液配比的正交试验,分析影响浆液性能的主要因素,发现水胶比、胶砂比、膨水比、灰粉比和泥粉比与浆液的坍落度、稠度、泌水率和凝结时间呈现不同的相关关系;以坍落度为主要控制指标,确定保证施工效果的最佳配合比,并在施工中取得了良好效果。

Synchronous grouting in shield tunneling is the key to control tunnel deformation,how to ensure the performance of synchronous grouting in marine environment is a problem that must be considered in slurry shield construction.A case study is conducted on shield tunnel of Su’ai Passageway.Comparative test is implemented,and the test results show that the synchronous thick grount mixed with sea water is superior to that mixed with fresh water in terms of fluidity,setting time,flexural strength,compressive strength,and consolidation shrinkage.At the same time,orthogonal experiment of grout mixing test inmarine environment were carried out to investigate the main influencing factor on grout performance,obtaining that the water-binder ratio,binder-sand ratio,bentonite-water ratio,fly ash-silt ratio,mud-silt ratio had different correlations with slumps,consistency,bleeding rate,setting time.Taking slump as the main control index,the optimal mix ratio of construction effect was determined,and good results were achieved in the construction site.