高钛重矿渣轻骨料对盾构隧道管片混凝土性能的影响  

Effect of titanium-rich heavy slag lightweight aggregate on properties of segment concrete for shield tunnel

作　　者：梁玉强 徐文礼 丁庆军[2] 张高展 LIANG Yuqiang;XU Wenli;DING Qingjun;ZHANG Gaozhan(China Communications Construction Company Limited Tunnel Engineering Company Limited,Nanjing 210043,China;School of Materials Science and Engineering,Wuhan University of Technology,Wuhan 430070,China;School of Materials and Chemical Engineering,Anhui Jianzhu University,Hefei 230601,China)

机构地区：[1]中交隧道工程局有限公司,江苏南京210043 [2]武汉理工大学材料科学与工程学院,湖北武汉430070 [3]安徽建筑大学材料与化学工程学院,安徽合肥230601

出　　处：《混凝土》2022年第6期142-146,共5页Concrete

基　　金：国家自然科学基金项目(U21A20149)。

摘　　要：为了解决现有盾构隧道管片混凝土材料存在的易开裂、渗漏等耐久性问题,基于密实骨架堆积设计原理和高钛重矿渣轻骨料的轻质和内养护特性,设计制备了一种C50轻质隧道管片混凝土,并研究了该混凝土的耐久性能。试验结果表明:利用高钛重矿渣轻骨料可以制备出性能优异的盾构隧道用C50轻质管片混凝土,该轻质隧道管片混凝土工作性能良好,表观密度仅为1980 kg/m^(3),28 d抗压强度可达61.0 MPa以上,180 d收缩率仅为265με,抗渗等级达P12,氯离子渗透系数仅为1.3×10^(-12) m^(2)/s,抗碳化性能、抗硫酸盐侵蚀性能和抗冻性能优异;高钛重矿渣轻骨料的强度、表观密度、颗粒级配和掺量等是影响该轻质管片混凝土性能的关键因素;高钛重矿渣轻骨料的内养护效应是提升该轻质隧道管片混凝土耐久性的关键。In view of the durability problems,including cracking and leakage,faced by the current shield tunnel segment concrete materials,based on the designing method of dense skeleton accumulation and the internal curing effect of titanium-rich heavy slag porous aggregate,a kind of C50 lightweight shield tunnel segment concrete was designed and prepared,and its durability was studied.The results show that the lightweight segment concrete for shield tunnel can be prepared with titanium-rich heavy slag lightweight aggregate,and it has a good working performance,an apparent density of only 1980 kg/m3,a 28 d compressive strength up to 61.0 MPa,an 180 d shrinkage rate of only 265με,a permeability grade up to P12,a chloride permeability coefficient only 1.3×10^(-12) m^(2)/s,and a excellent carbonation resistance,sulfate corrosion resistance and freezing resistance.The strength,apparent density,particle size and mixing amount of titanium-rich heavy slag aggregate are the key factors affecting the performance of concrete.The internal curing effect of titanium-rich heavy slag lightweight aggregate is the key to improve the durability of lightweight shield tunnel segment concrete.

关 键 词：高钛重矿渣轻骨料 管片混凝土 表观密度 力学性能 耐久性能 

分 类 号：TU528.7[建筑科学—建筑技术科学]