冻结井壁高性能混凝土细观结构研究

Research on Mesostructure of HPC Applied in Frozen Shaft Lining

针对冻结井壁施工环境条件,对比高性能混凝土材料掺合料水化反应前后材料细观特征,利用扫描电镜观察高性能混凝土细观结构,高性能混凝土在结构中的微裂隙和孔洞较普通混凝土相比数量较少。掺合料的水化反应更为充分,水泥凝胶随时间增加,与掺合料里面的活性成分进一步反应,将原始裂隙进行修补,水泥石更加致密。高性能混凝土强度进一步提高,减少了结构自重;高性能混凝土耐久性好,进而延长了井筒使用时间。

In the conditions of frozen shaft lining construction, the different hydration reaction of mesoscopic characteristic is reflected by adding admixture materials to high performance concrete,making use of SEM(scanning electronic microscopy) observes the microscopic structure of HPC(high performance concrete), it concluded that HPC in the structure of the micro cracks and holes compared with fewer than those of normal concrete. Admixture of hydration reaction is more sufficient, cement gel increases with time, and the active ingredient of admixture further reacts, the original crack is repaired,cement will be denser. High performance concrete strength is further improved, the structure weight is reduced;High performance concrete has good durability,and the using time of wellbore is prolonged.