(1 湖南科技大学土木工程学院, 湘潭 411201; 2 广东盖特奇新材料科技有限公司, 清远 511600)

摘要: 基于超高性能混凝土(ultra-high performance concrete,简称为 UHPC)良好的受力性能,提出了一种由钢板-UHPC 薄层-普通混凝土叠合而成的新型栓钉组合剪力键,用于增强基础环式风力机基础中基础环与混凝土间的界面抗拔能力. 通过对 1􀏑3 缩尺模型进行了 3 组共 9 个静力拔出试验,研究了 UHPC 薄层厚度对新型栓钉组合剪力键的荷载-滑移曲线、破坏形态及极限承载能力的影响. 结果表明,整个受力过程可经历 4 个阶段,即界面间摩擦传力弹性阶段、栓钉受剪弹性和弹塑性阶段、混凝土受拉破坏阶段. UHPC 薄层的加入,栓钉不仅在钢板与 UHPC 薄层界面(简称第一界面)即栓钉根部出现了塑性,同时在 UHPC 薄层-普通混凝土交界面(简称第二界面)上亦出现了明显的塑性,使得新型栓钉组合剪力键抗剪刚度及承载力均较普通栓钉剪力键有显著提高. 同时栓钉根部剪应力峰值明显降低,有效提高了剪力键的抗拔性能. 基于试验结果,提出了基于双界面栓钉屈服的新型栓钉组合剪力键抗拔承载力计算公式. 对比结果表明,该公式能较好反映 UHPC 薄层厚度对承载力的贡献.

关键词: UHPC 薄层; 栓钉; 风力机基础; 组合剪力键; 拔出试验

中图分类号:TU359,TU92+3 文献标志码:A 文章编号:1002-848X(2023)05-0141-07

DOI:10. 19701 / j. jzjg. LS210365

Experimental study on the pull-out performance of a new stud combined shear connector with UHPC thin layer

LÜ Weirong1, MA Huixin1, LU Beirong1, ZHOU Qingqi1, ZHAO Sitai1, LIU Fucai2, QI Jingjing1

(1 Department of Civil Engineering, Hunan University of Science and Technology, Xiangtan 411201, China;2 Guangdong Gateqi New Material Technology Co. , Ltd. , Qingyuan 511600, China)

Abstract: Based on great mechanical performance of ultra-high performance concrete ( UHPC), a new type of studcombined shear connector composed of steel plate, UHPC thin layer and ordinary concrete was proposed to strengthen theinterface pulling ability between foundation ring and concrete. The effects of UHPC thin layer thickness on load-slip curve,failure modes and ultimate bearing capacity of the new stub composite shear connector were studied by using 3 sets of 9static pull-out tests on the 1􀏑3 scale model. The results show that the whole loading process can be divided into fourstages, namely the elastic stage of friction force transfer between interfaces, the elastic and elastoplastic stages of studshear, and the tensile failure stage of concrete. With the addition of UHPC thin layer, the studs not only appear plastic atthe interface between steel plate and UHPC thin layer (referred to as the first interface) namely the root of the studs, butalso appear obvious plastic at the interface between UHPC thin layer and ordinary concrete ( referred to as the secondinterface), which makes the shear rigidity and bearing capacity of the new stub composite shear connector improvesignificantly than the ordinary stud shear stud. Meanwhile, the peak value of shear stress at the root of stud decreasesobviously, which effectively improves the shear performance of the new stud composite shear connector. Based on theresults of test, a formula according to the yield criterion for double interface studs for calculating the shear capacity of thenew stub composite shear connector was put forward. The comparison results show that the formula can reflect thecontribution of thickness of UHPC thin layer to the bearing capacity, and can be used for reference in practical engineering.

Keywords:UHPC thin layer; stud; wind turbine foundation; combined shear connector; uplift test

∗国家自然科学基金面上项目( 51578235),湖南省自然科学基金项目面上项目( 2021JJ30261),湖南省教育厅重点项目(20A184).

第一作者:吕伟荣,博士,教授,主要从事钢-混组合结构、砌体结构、工程抗震研究,Email: lwrxm@ 126. com.

[引用本文] 吕伟荣,马慧心,卢倍嵘,等. 含 UHPC 薄层的新型栓钉组合剪力键抗拔性能试验研究[J]. 建筑结构,2023,53(5):141-147. LÜ Weirong,MA Huixin,LU Beirong,et al. Experimental study on the pull-out performance of anew stud combined shear connector with UHPC thin layer[J]. Building Structure,2023,53(5):141-147.