新型喷射混凝土复合减弹剂的研究与应用

Research and Application of New Compound Rebound Reducing Agents in Sprayed Concrete

本文通过分析引起湿喷喷射混凝土回弹率高的主要原因,研发一种具有普通减水剂、增粘剂、促凝早强剂以及防水剂效果的复合型减弹剂。研究结果表明,当隧道围岩有渗水,复合型减弹剂掺量为3%时,复合型减弹剂中各组分为:减水母液9%,保坍母液9%,引气剂0.05%,增粘剂0.12%,促凝早强剂10%,防水剂1.2%,能将湿喷喷射混凝土回弹率从22%降到10%以下,显著提高喷射混凝土的早期强度,并能有效改善喷射混凝土的工作性及稳定性。

This paper analyses the main causes of the high reboundrate of wet sprayed concrete and develops a composite rebound reducing agent that combines the effects of general water reducing agents,viscosity enhancers,coagulants and waterproofing agents.The test results show that when there is water seepage in the surrounding rock of tunnel,when the composite rebound reducing agent is mixed at 3% with the following components:water reducing agent mother liquor 9%,slump-proof agent mother liquor 9%,air-entraining agent 0.05%,viscosity enhancer 0.12%,coagulant 10%,waterproofing agent 1.2%,which can reduce the rebound rate of wet sprayed concrete from 22% to less than 10%,significantly improve the early strength of shotcrete,and it can effectively improve the workability and stability of the shotcrete.