- 摘 要
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(1 國電電力發(fā)展股份有限公司, 北京 100101; 2 同濟大學建筑設(shè)計研究院 (集團) 有限公司,上海 200092; 3 海南中海電力工程有限公司, 海口 570100)
摘要: 提出一種預應力擴底錨索結(jié)構(gòu),通過擴底端與圍巖之間形成擠壓摩擦錨固,并對鋼絞線施加預拉力減小其疲勞應力幅,可代替普通巖石錨桿作為抗疲勞結(jié)構(gòu)用于巖石地基基礎(chǔ)中. 對強風化巖石地基中的預應力擴底錨索分別進行了現(xiàn)場疲勞試驗和靜力試驗,共計 7 組試驗. 試驗結(jié)果表明,強風化巖石地基中,預應力擴底錨索可以承擔 200 萬次以上的疲勞荷載作用,估算疲勞應力幅為 148MPa,錨索的疲勞壽命和抗疲勞承載力較高;靜力試驗錨索最終發(fā)生鋼絞線斷絲破壞,錨頭均未被拔出,擴底端的錨固性能好,能充分發(fā)揮鋼絞線的抗拉強度. 經(jīng)過合理設(shè)計,預應力擴底錨索可以應用于具有疲勞作用的風電結(jié)構(gòu)強風化巖石地基基礎(chǔ)中.
關(guān)鍵詞: 預應力擴底錨索; 強風化巖石地基; 抗疲勞性能; 錨固性能
中圖分類號:TU471. 6 文獻標志碼:A 文章編號:1002-848X(2023)12-0132-06
DOI:10. 19701 / j. jzjg. 20201445
Anti-fatigue experimental research on pre-stressed under-reamed anchor cable in highly weatheredrock foundation
QU Zhongkan1, HE Guirong2, SUN Qi3
(1 GD Power Development Co. , Ltd. , Beijing 100101, China; 2 Tongji Architectural Design (Group) Co. ,Ltd. , Shanghai 200092, China; 3 Hainan Zhonghai Power Engineering Co. , Ltd. , Haikou 570100, China)
Abstract: A type of pre-stressed under-reamed anchor cable structure was proposed, which utilized the compression andfriction between the expanded bottom and the surrounding rock to anchor, and applied pre-tension to the steel strands toreduce their fatigue stress amplitude. It can replace the ordinary anchor rod as a fatigue-resistant structure in rockfoundation. Totally seven sets of experiments were conducted on site, including fatigue experiments and static experimentson pre-stressed under-reamed anchor cable in highly weathered rock foundations. The test result shows that in heavilyweathered rock foundations, the pre-stressed under-reamed anchor cable has higher fatigue life and anti-fatigue bearingcapacity, which could withstand more than 2 million cycles of fatigue load with 148MPa of an estimated fatigue stressamplitude. In the static tests, the steel strands of anchor cable eventually broke, but the anchor heads were not pulled out,which reveals that the anchoring performance of the expanded bottom was good, and the tensile strength of the steel strandscould be fully utilized. With reasonable design, pre-stressed under-reamed anchor cables can be applied in highlyweathered rock foundations of wind power structures with fatigue effects.
Keywords: pre-stressed under-reamed anchor cable; highly weathered rock foundation; anti-fatigue property;anchoring performance
第一作者:曲忠侃,學士,高級工程師,主要從事新能源開發(fā)工作,Email:quzk@ 600795. com. cn.
[引用本文] 曲忠侃,何桂榮,孫奇. 強風化巖石地基中預應力擴底錨索抗疲勞試驗研究[ J]. 建筑結(jié)構(gòu),2023,53(12):132-137. QU Zhongkan, HE Guirong, SUN Qi, et al. Anti-fatigue experimental research on pre-stressed underreamed anchor cable in highly weathered rock foundation[J]. Building Structure,2023,53(12):132-137.
