摘要
湿喷混凝土技术是公路隧道施工过程中较为常见的方式之一,回弹率较高是当前湿喷混凝土施工普遍存在的技术问题,如何采取有效措施降低回弹率一直是工程实践者们探讨的热点话题。针对机制砂混凝土回弹率较高的问题,进行了不同掺量速凝剂、减水剂的配合比影响试验,同时从湿喷混凝土中粗骨料的回弹机理出发,进行贯入试验,并对喷射方式进行了改进。结果表明,采用先喷水泥砂浆再喷混凝土可以有效降低回弹率,研究成果可对降低工程成本和缩短施工工期起到积极作用。
Wet shotcrete technology is one of the most common methods in the construction of a highway tunnel.The high rebound rate is a common technical problem in the current wet shotcrete construction.It is a hot topic for engineer ing practitioners to take adequate measures to reduce the rebound rate.Aiming at the issue of a high rebound rate of machine-made sand concrete,the influence test of different proportions of accelerator and water reducer was carried out.At the same time,the penetration test was carried out based on the rebound mechanism of coarse aggregate in wet shotcrete,and the spraying method was improved.The results show that the rebound rate can be effectively reduced by spraying cement mortar first and then concrete,and the research results can play a positive role in reducing project cost and construction period.
作者
刘长文
Liu Changwen(The Sixth Engineering Co.,Ltd.of China Railway 19th Bureau Group Co.,Ltd.,Wuxi 214000,China)
出处
《市政技术》
2020年第6期49-52,共4页
Journal of Municipal Technology
关键词
公路隧道
湿喷混凝土
回弹率
速凝剂
减水剂
highway tunnel
wet shotcrete
resilience
accelerator
water reducer
