砂层注浆模型试验及注浆体水泥含量检测方法研究
Study on Cement Content Detection of Experimental Investigation of Grouting Model Test into Sand Stratum

地铁建设中预注浆加固方式，为研究预注浆工程中浆液扩散规律及分布情况，研制一套由加压稳定系统、模型箱系统和注浆系统组成的注浆模型试验装置。采用改进型EDTA二钠滴定检测水泥土中水泥含量的试验方法，在注浆影响范围内分块取样，与滴定检测结合形成分块滴定法并进行一次完整注浆试验验证。研究结果表明：注浆模型试验装置效果良好，改进型EDTA二钠滴定法能准确检测水泥土中水泥含量，分块滴定法能直观地显示浆液分布情况和扩散范围，为类似模型试验研究浆液分布提供一种合理可行的试验方法。
Pre-grouting reinforcement was a common pattern in subway construction. The grouting model test equipment with an assembly of stable pressurization system, model box system and grouting system was developed to study diffusion and distribution of slurry in pre-grouting projects. Sodium EDTA titration method was improved to detect the cement content in cement soil. And this was combined with cutting samples in the range of the grouting influence to develop a block titration method and implement a complete grouting test. Results showed that the grouting model test equipment worked well, improved sodium EDTA titration method can detect the cement content in cement soil accurately, a visually clearer and more presentable distribution and diffusion range of slurry can be obtained by block titration method, a reasonable and feasible test method has been established to study the distribution of slurry for similar tests..