为研究橡胶粉改性聚乙烯纤维增强水泥基复合材料（PE-ECC）的物理力学性能，对掺入不同粒径橡胶粉的PE-ECC进行静力和抗冲击性能试验。通过分析橡胶粉PE-ECC的弹性模量、泊松比、立方体抗压强度、轴心抗压强度、劈裂抗拉强度和轴心抗拉强度，探讨不同橡胶粉粒径对PE-ECC基本力学性能的影响；利用分离式霍普金森压力杆进行橡胶粉PE-ECC的抗冲击性能试验，基于不同应变率下的动态应力-应变曲线，分析应变率对橡胶粉PE-ECC动态增长因子（DIF）、动态压缩强度和动态峰值应变的影响。结果表明：随着橡胶粉的加入，PE-ECC的各项物理力学性能均有一定程度下降；橡胶粉粒径为0.20~0.90 mm时，体积掺量为10%、橡胶粉粒径为0.30 mm的PE-ECC各项力学性能降幅最小，其立方体抗压强度、轴心抗压强度、弹性模量和动态抗压强度相对无橡胶粉PE-ECC分别减小了8.9%、15.6%、10.8%和23.4%；与无橡胶粉PE-ECC类似，橡胶粉PE-ECC的受拉应变硬化特征明显，掺入不同粒径（0.20~0.90 mm）橡胶粉的PE-ECC极限拉应变均稳定在4.6%左右。此外，橡胶粉粒径对PE-ECC动态峰值应变影响很小，随着冲击应变率的提高，橡胶粉PE-ECC的动态增长因子DIF和动态压缩强度呈逐渐增大趋势。

In order to investigate the mechanical properties of polyethylene fiber-reinforced engineered cementitious composites (PE-ECC) with rubber powder, static and impact resistance tests were carried out on the PE-ECC with varying parameters of rubber powder particle sizes and strain rates. Elastic modulus, Poisson,s ratio, cubic compressive strength, primal strength, splitting tensile strength, and axial tensile strength of the rubber powder PE-ECC were experimentally obtained, and the influence of rubber powder particle sizes on static mechanical properties of the PE-ECC were analyzed. The impact performance of the PE-ECC with rubber powder was evaluated using a split Hopkinson pressure bar, and the dynamic growth factor of strain rate on the dynamic impact factor (DIF), peak dynamic stress, and peak dynamic strain were analyzed. The experimental results indicate that the mechanical properties of the PE-ECC decreased with the usage of rubber powder. For the particle size of rubber powder ranged from 0.2 mm to 0.9 mm, the PE-ECC with particle sizes of 0.3 mm for rubber powder exhibited acceptable static and dynamic performance. Comparing to the PE-ECC without any rubbers, the cubic compressive strength, primal strength, elastic modulus, and dynamic compressive strength of the PE-ECC using 0.30 mm-particle size rubber powder and a volume content of 10% decreased by 8.9%, 15.6%, 10.8%, and 23.4%. Similar to the PE-ECC without rubber powder, the tensile strain hardening effect of rubber powder P-ECC was significant and the ultimate tensile strain of PE-ECC with different partial size (0.20-0.90 mm) rubber powder remained at 4.6%. Moreover, with the increase of impact strain rate, the DIF and dynamic compressive strength of rubber powder PE-ECC gradually increased.

TU599;TB332

国家自然科学基金（51908138）；广东省自然科学基金（2020A1515011355）