- 摘 要
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(1 湖南科技大學(xué)土木工程學(xué)院, 湘潭 411201; 2 廣東蓋特奇新材料科技有限公司, 清遠 511600)
摘要: 基于超高性能混凝土(ultra-high performance concrete,簡稱為 UHPC)良好的受力性能,提出了一種由鋼板-UHPC 薄層-普通混凝土疊合而成的新型栓釘組合剪力鍵,用于增強基礎(chǔ)環(huán)式風(fēng)力機基礎(chǔ)中基礎(chǔ)環(huán)與混凝土間的界面抗拔能力. 通過對 1??3 縮尺模型進行了 3 組共 9 個靜力拔出試驗,研究了 UHPC 薄層厚度對新型栓釘組合剪力鍵的荷載-滑移曲線、破壞形態(tài)及極限承載能力的影響. 結(jié)果表明,整個受力過程可經(jīng)歷 4 個階段,即界面間摩擦傳力彈性階段、栓釘受剪彈性和彈塑性階段、混凝土受拉破壞階段. UHPC 薄層的加入,栓釘不僅在鋼板與 UHPC 薄層界面(簡稱第一界面)即栓釘根部出現(xiàn)了塑性,同時在 UHPC 薄層-普通混凝土交界面(簡稱第二界面)上亦出現(xiàn)了明顯的塑性,使得新型栓釘組合剪力鍵抗剪剛度及承載力均較普通栓釘剪力鍵有顯著提高. 同時栓釘根部剪應(yīng)力峰值明顯降低,有效提高了剪力鍵的抗拔性能. 基于試驗結(jié)果,提出了基于雙界面栓釘屈服的新型栓釘組合剪力鍵抗拔承載力計算公式. 對比結(jié)果表明,該公式能較好反映 UHPC 薄層厚度對承載力的貢獻.
關(guān)鍵詞: UHPC 薄層; 栓釘; 風(fēng)力機基礎(chǔ); 組合剪力鍵; 拔出試驗
中圖分類號:TU359,TU92+3 文獻標志碼:A 文章編號: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
∗國家自然科學(xué)基金面上項目( 51578235),湖南省自然科學(xué)基金項目面上項目( 2021JJ30261),湖南省教育廳重點項目(20A184).
第一作者:呂偉榮,博士,教授,主要從事鋼-混組合結(jié)構(gòu)、砌體結(jié)構(gòu)、工程抗震研究,Email: lwrxm@ 126. com.
[引用本文] 呂偉榮,馬慧心,盧倍嶸,等. 含 UHPC 薄層的新型栓釘組合剪力鍵抗拔性能試驗研究[J]. 建筑結(jié)構(gòu),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.
