高地热隧道衬砌混凝土的配制参数研究  

Research on the preparation parameters of lining concrete for high geothermal tunnel

作　　者：高龙 李享涛 付志勇 GAO Long;LI Xiangtao;FU Zhiyong(Tiezheng Testing Technology Co.,Ltd.,Jinan 250014,China;Institute of Railway Construction,China Academy of Railway Sciences Group Co.,Ltd.,Beijing 100081,China)

机构地区：[1]铁正检测科技有限公司,山东济南250014 [2]中国铁道科学研究院集团有限公司铁道建筑研究所,北京100081

出　　处：《混凝土与水泥制品》2023年第9期27-31,40,共6页China Concrete and Cement Products

摘　　要：针对西部地区隧道施工面临的高地热问题,研究了水泥种类对20、60、80℃的衬砌混凝土早期水化温升和抗压强度的影响,并模拟分析了隧道地热环境下不同含气量衬砌混凝土的塑性变形及抗压强度增长规律、外掺石粉制备的低含气量衬砌混凝土的工作性和力学性能以及不同种类保水剂对衬砌混凝土早期失水率的影响,提出了高地热隧道衬砌混凝土的最佳配制参数。结果表明:在高地热环境下低热水泥衬砌混凝土的水化温升较普通水泥衬砌混凝土降低了4℃,90 d抗压强度提高了11.5%~16.5%;衬砌混凝土的含气量越高,高温对其后期强度的降低幅度越显著;复掺石粉可有效改善低含气量衬砌混凝土的工作性,石粉掺量宜为6%~15%;保水剂聚丙烯酰胺对抑制衬砌混凝土早期失水的作用优于纤维素醚,聚丙烯酰胺掺量宜为0.05%~0.10%。In view of the high geothermal problem faced by tunnel construction in the western region,the influence of cement types on the early hydration temperature rise and compressive strength of lining concrete under 20,60 and 80℃ambient temperatures was studied.The laws of plastic deformation and compressive strength growth of lining concrete with different air content under simulated tunnel geothermal environment were analyzed.The workability and mechanical properties of lining concrete with low air content prepared by adding stone powder were compared.The influence of different water retaining agents on the water loss rate of lining concrete was studied,and the preparation parameters of the lining concrete for high geothermal tunnel were proposed.The results show that the hydration temperature rise of low hydration heat cement lining concrete is reduced by 4℃compared to ordinary cement lining concrete under high geothermal environment,and the 90 d compressive strength is increased by 11.5%to 16.5%.The higher the air content of lining concrete is,the more significant the later strength of lining concrete caused by high temperature decrease.Composite addition of stone powder can effectively improve the workability of low air content lining concrete,and the suitable stone powder content is about 6%to 15%.The effect of polyacrylamide on inhibiting early water loss of lining concrete is better than that of cellulose ether,and the suitable content of polyacrylamide is 0.05%to 0.10%.

关 键 词：高地热隧道 衬砌混凝土 水化温升 制备参数 含气量 

分 类 号：TU528.01[建筑科学—建筑技术科学]