聚合物对超高韧性水泥基复合材料性能的影响

摘要

The ultra-high toughness cementitious composites(UHTCC) were modified by styrene-acrylic emulsion and epoxy emulsion,the effect of the emulsion on the mechanical properties,bond strength and shrinkage of UHTCC was studied.The results show that compared with the unmodified UHTCC,the compressive strength and flexural strength of the modified UHTCC by styrene-acrylic emulsion and epoxy emulsion are lower,but the bonding strength is higher,the shrinkage rate is lower;the ultimate stress and initial stress at early age of styrene-acrylic emulsion modified UHTCC is decreased,but initial stress is increased at 90 d age,the ultimate strain is unchanged,and the initial strain is increased;,the ultimate stress,the initial stress and initial strain of epoxy emulsion modified UHTCC are increased,but the ultimate strain is decreased,the tensile strain hardening phenomenon is not significant.%采用苯丙乳液和环氧乳液对超高韧性水泥基复合材料(UHTCC)进行改性,研究二者对UHTCC力学性能、黏结强度、收缩率的影响.结果表明:对比未改性UHTCC,苯丙乳液和环氧乳液改性的UHTCC抗压强度和抗折强度均降低,但黏结强度提高,收缩率减小;苯丙乳液改性UHTCC的极限应力和早期初裂应力降低,但90 d的初裂应力提高,极限应变保持不变,初裂应变增大;环氧乳液改性UHTCC的极限应力、初裂应力提高,初裂应变增大,但极限应变减小,拉伸应变硬化现象不显著.