摘要
本文将钢纤维和聚乙烯(PE)纤维进行混杂,制备了钢-PE混杂纤维水泥基复合材料(S/PE-HFRECC, Steel-PE Hybrid Fiber Reinforced Engineered Cementitious Composites),控制纤维体积总掺量为2%,通过改变两种纤维配比制作了六类水泥基试件(S0E0、S0E2、S0.5E1.5、S1E1、S1.5E0.5和S2E0),并利用可施加预加静态荷载的直径为50 mm的分离式霍普金森压杆(Split Hopkinson Pressure Bar, SHPB)装置开展了静动组合加载条件下S/PE-HFRECC的动态压缩试验,预加静荷载级别分别取试件静态抗压强度的0%、15%、30%和45%四个级别。试验结果表明:1) 预加静态荷载对水泥基复合材料的力学性能有着弱化和强化的双面性。2) S/PE-HFRECC的动态抗压强度、动态峰值应变和应力峰值前韧度随着预加静荷载级别的提高呈现先升高后降低的趋势。3) 相较于单一纤维的掺入,钢-PE混杂纤维在对强度、变形能力和韧度的改善方面有着更好的优越性。
In this paper, the Steel-PE Hybrid Fiber Reinforced Engineered Cementitious Composites (S/PE- HFRECC) were prepared by blending steel fiber and PE fiber, with a controlled total fiber volume content of 2%. Six types of cement-based specimens (S0E0, S0E2, S0.5E1.5, S1E1, S1.5E0.5 and S2E0) were fabricated by varying the ratio of the two types of fibers. A Split Hopkinson Pressure Bar (SHPB) device with a diameter of 50 mm was utilized to conduct dynamic compression tests on the S/PE- HFRECC under static and dynamic combined loading conditions, allowing for pre-static load application at levels corresponding to 0%, 15%, 30% and 45% of the static compressive strength. The test results show that: 1) The mechanical properties of cement-based composites are influenced by preloading static load, resulting in both weakening and strengthening effects. 2) The dynamic compressive strength, dynamic peak strain, and pre-peak stress toughness of S/PE-HFRECC initially increase and then decrease with increasing levels of pre-static load. 3) Compared to single fiber inclusion, steel-PE hybrid fiber exhibits superior advantages in enhancing strength, deformation ability, and toughness.
出处
《土木工程》
2024年第5期626-637,共12页
Hans Journal of Civil Engineering
