纵筋搭接式钢纤维硫铝酸盐水泥混凝土节点装配式柱抗震性能

Seismic performance of precast columns with steel fiber reinforced sulphoaluminate cement concrete joints using longitudinal reinforcement lapping

  • 摘要: 设计了一种早强高强、装配便捷、精度要求低的纵筋搭接式钢纤维硫铝酸盐水泥混凝土节点装配式钢筋混凝土柱。为研究其抗震性能,对2种纵筋搭接长度(100 mm和300 mm)的装配式柱试件和1个现浇柱试件进行了拟静力试验。结果表明:装配式柱震后混凝土损伤程度远低于现浇柱,提高纵筋搭接长度可以改善装配式柱的抗震性能。钢纤维硫铝酸盐水泥混凝土浇筑7天后,相较于现浇柱,搭接长度100 mm和300 mm的装配式柱峰值荷载降低了14.75%和1.24%,初始刚度降低57.09%和11.63%,累积耗能降低71.32%和13.61%;搭接长度300 mm的装配式柱延性系数较现浇柱提高6%。当搭接长度达到300 mm时,装配式柱可基本实现“等同现浇”的承载能力、刚度和耗能能力,以及“超越现浇”的震后完整性和延性。

     

    Abstract: This study designed a prefabricated reinforced concrete column (PRCC) with steel fiber reinforced sulphoaluminate cement concrete joints using longitudinal reinforcement lapping featuring early strength, high strength, convenient assembly and low precision requirements. To investigate the seismic performance of this type of PRCCs, pseudo-static tests were conducted on the PRCC specimens with two kinds of lapping lengths (i.e. 100 mm and 300 mm) and one cast-in-place reinforced concrete column (CRCC) specimen. The results show that the damage level of post-earthquake concrete of PRCCs is far lower than that of CRCC. The seismic performance of PRCCs is improved when the lapping length increased. Seven days after the pouring of steel fiber sulphoaluminate cement concrete, compared to the CRCC, the peak loads of PRCCs with lapping lengths of 100 mm and 300 mm decrease by 14.75% and 1.24%, respectively, while the initial stiffness decreases by 57.09% and 11.63%, and cumulative energy dissipation decreases by 71.32% and 13.61%. In addition, the ductility coefficient of the PRCC with the lapping length of 300 mm increases by 6% compared to the CRCC. As the lapping length reaches 300 mm, the PRCC can basically achieve the same bearing capacity, stiffness and energy dissipation capacity as those of CRCC, as well as better post-earthquake integrity and ductility compared to cast-in-place CRCC.

     

/

返回文章
返回