机制砂泵送纤维混凝土在地下超长结构中的应用

Application of manufactured sand pumping fiber concrete in the structure of underground overlength structure

本文针对山东平度地区的尾矿机制砂,开展了尾矿机制砂与河砂复合使用,对泵送纤维混凝土新拌性能、力学性能、收缩性能及渗透性能影响的试验研究。试验结果表明:河砂与机制砂复合使用时可明显改善尾矿机制砂对混凝土新拌性能的影响;尾矿机制砂配制的纤维混凝土收缩有增大的趋势,但混凝土强度和抗渗性能可得到改善;综合考虑混凝土性能与经济性,河砂与尾矿机制砂的比例为2∶8时配制的纤维泵送混凝土具有良好的防渗抗裂效果。

Based on the properties of tailing manufactured sand in the Shandong Pingdu area,influences of manufactured sand and river sand on the performance of fiber reinforced concrete were investigated.The experimental results show that river sand can significantly reduce the influence of tailing manufactured sand on the concrete construction performance.Tailings manufactured sand increase the shrinkage of fiber concrete,but manufactured sand can improve strength and impermeability of fiber concrete.Considering the concrete performance and economy,the fiber reinforced pumping concrete has good crack resistance and seepage control performance,when river sand and tailing manufactured sand proportion is 2:8.