为抑制盾构在富水硬岩段施工过程中的管片上浮，研制一种二次注浆用的新型轻质浆液。该浆液悬浮于管片上方，能快速凝固，可达到抑制管片上浮的目的。通过对比筛选，确定以憎水膨胀珍珠岩、高贝利特硫铝酸盐水泥、絮凝剂UWB-Ⅱ、UWB-Ⅲ和聚羧酸减水剂BSH-200等作为新型轻质浆液试验原材料。用正交试验方法研究各因素对容重、抗压强度、抗分散性等浆液性能的影响，优选配合比，同时进行现场试验验证，结果表明，该轻质浆液对管片上浮有明显的抑制作用。
A new type of lightweight slurry for secondary shield
grouting is developed to inhibit the floating of shield segments during
tunneling in waterrich hardrock
sections. The slurry is suspended above the segment, and it can rapidly
solidify. According to comparison and selection, the hydrophobic expanded
perlite, high belite sulfur aluminate cement, flocculant UWB Ⅱ and UWB Ⅲ, and polycarboxylic
superplasticizer BSH200 can be employed as test raw
materials. The effect of various factors on the properties of the slurry,
including bulk density, compressive strength, and dispersion resistance, is
investigated using the orthogonal test method. Finally, the optimal mix ratio
for the slurry is obtained and verified via field test. The results show that
the lightweight slurry has an inhibiting effect on the floating of segments.
