盾构施工同步双液注浆材料的配合比及性能研究

Research on the proportion and properties of a simultaneous two-component backfill grouting material in shield construction

以温州地铁隧道盾构施工为工程背景,分别采用水泥浆体、水玻璃以一定体积比例与可硬化抗剪性浆液混合形成双液型同步注浆,通过室内试验对不同配合比下双液浆的特性进行了分析。结果表明:随着水泥浆体水灰比减小,或水玻璃波美度增大,双液浆的泌水率下降,稠度损失加快,抗剪切强度及无侧限抗压强度逐步提高。根据性能指标要求,所加入的水泥浆体的水灰比应小于0.33或水玻璃的波美度应高于12°Be′,但不建议水灰比过小或波美度过高,否则将造成施工困难。

The shield construction of tunnel in Wenzhou subway is taken as the background of project.A type of two-component backfill grouting material is first prepared by mixing cement paste or water glass with a hardenable shear-resistant grout by a certain volume ratio.Then the properties of the two-component grout with different proportions is analyzed by indoor experiments.Results show that the bleeding value decreases,the rate of consistency loss increases,and the shear resistance and the unconfined compressive strength increases gradually along with a decrease of water-to-cement ratio of cement paste or an increase of Baume degree of water glass.As required by the designed properties of backfill grout,the water-to-cement ratio of cement paste should be lower than 0.33,or the Baume degree of water glass should be higher than 12°Be′.However,much lower of water-to-cement ratio or much higher of Baume degree is not advised because it will lead to difficulty in construction.