超高韧性水泥基材料的制备技术

分别采用活性粉末混凝土（RPC）和渗浇钢纤维混凝土（SIFCON）两种制备工艺，根据水泥基材料结构的多尺度特征，研究了由碳酸钙晶须和微钢纤维复合增强的超高韧性水泥基材料（Ultra-High-Toughness Cementitious Composite，简称UHTCC）的制备技术，测试UHTCC不同配比的抗压强度、抗折强度、抗弯强度以及单轴拉伸性能，采用折压比、韧性指数等多个指标对UHTCC的韧性进行了评价。试验表明：UHTCC的抗压强度、抗折强度、抗弯强度以及延性和韧性都远高于普通钢纤维混凝土，其抗弯强度最高达65.1 MPa、韧性指数I₂₀最高达49.21，单轴拉伸试验时呈现明显的假应变硬化行为，极限拉应变可达4%~8%。相对而言，利用SIFCON工艺制得的水泥基材料韧性更高。

Preparation technology of the ultra-high-toughness cementitious composite

The preparation technology of reactive powder concrete (RPC) and slurry infiltrated fiber concrete (SIFCON)were adopted respectively, according to the multi scale structure characteristic of cementitious composites, the preparation technology of the ultra-high-toughness cementitious composite(UHTCC) reinforced by calcium carbonate whisker and micro steel fiber were studied, and the compressive strength, flexural strength, bending strength and mechanical properties uniaxial tension of different mixture proportions were tested. The ratio of flexural-compressive strength, toughness index and other more index were used to evaluate the toughness of the UHTCC. The experimental results indicate that the compressive strength, flexural strength, bending strength, ductility and toughness of UHTCC are much higher than those of general steel fiber concrete. The bending strength of UHTCC and the toughness index I₂₀ are up to 65.1MPa and 49.21 respectively. False strain-hardening behavior of UHTCC are achieved under uniaxial tension. The ultimate tensile strain of UHTCC can reach 4%~8%. Compared to RPC technology, higher toughness are obtained using SIFCON technology.