轻质工程水泥基复合材料基体优化设计及性能研究  

Optimization design and performance study of lightweight engineered cementitious composite

作　　者：丁庆军[1] 王君[1] 廖庆尧 马雪婷 DING Qingjun;WANG Jun;LIAO Qingyao;MA Xueting(State Key Laboratory for Silicate Building Materials,Wuhan University of Technology,Wuhan 430070,China)

机构地区：[1]武汉理工大学硅酸盐建筑材料国家重点实验室,湖北武汉430070

出　　处：《混凝土》2025年第2期74-79,共6页Concrete

基　　金：国家自然科学基金联合基金重点项目(U21A20149)。

摘　　要：工程水泥基复合材料(ECC)由于其拉伸应变硬化行为和紧密多裂缝的独特特性确保能够满足混凝土基础设施韧性和耐久性的严格要求。以国产PVA纤维代替日本可乐丽纤维,使用粉煤灰漂珠(FAC)代替细石英砂作为轻质细集料,通过调整粉煤灰与水泥比例和引入一定体积和粒径的轻质球形陶粒等方法对基体进行优化设计,对轻质ECC的强度、单轴拉伸性能、薄板四点弯曲性能和干燥收缩性能等进行试验研究。结果表明:两种优化方法均是有效的。当粉煤灰与水泥3∶1时,在此基础上引入5%体积的4.0~4.5 mm的球形陶粒轻质ECC的综合性能最好,表观密度≤1750 kg/m^(3),抗压强度≥50 MPa,单轴拉伸应变超过5%,薄板弯曲挠度增加至25 mm。而饱水预湿多孔陶粒可形成内养护作用,对ECC进行补偿收缩,提高其体积稳定性。Engineered cementitious composite(ECC),due to their tensile strain hardening behavior and unique characteristics of tight multiple cracks,ensure that they can meet the strict requirements for toughness and durability of concrete infrastructure.Domestic PVA fiber is used to replace Japanese Kuraray fiber,and fly ash floating beads(FAC)are used to replace fine quartz sand as lightweight fine aggregate.The matrix is optimized by adjusting the ratio of fly ash to cement and introducing lightweight spherical ceramsite with a certain volume and particle size.The strength,uniaxial tensile properties,four point bending properties and drying shrinkage properties of lightweight ECC are tested and studied.The results indicate that both optimization methods are effective.When the ratio of fly ash to cement is 3∶1,the introduction of 5%volume from 4.0 mm to 4.5 mm spherical ceramsite lightweight ECC has the best comprehensive performance,with an apparent density≤1750 kg/m^(3),compressive strength≥50 MPa,uniaxial tensile strain exceeding 5%,and bending deflection of the thin plate increasing to 25 mm.However,saturated pre wetting porous ceramic particles can form an internal curing effect,compensating for shrinkage of ECC and improving its volume stability.

关 键 词：轻质ECC 韧性 基体优化 干燥收缩 

分 类 号：TU528.041[建筑科学—建筑技术科学]