钢筋抗浮锚杆外锚固承载性能试验研究
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摘要
通过专门设置的现场拉拔试验,测定几种钢筋抗浮锚杆外锚固(与基础底板锚固)极限抗拔承载力和滑移量,分析其承载性能和受力机理。研究表明,在标号C30混凝土底板中,相同直径与弯曲半径,不同竖直锚固长度与弯折长度的钢筋抗浮锚杆,均发生拔断破坏,破坏荷载均大于340kN,最大滑移量为11~21mm,各锚杆断裂位置均发生在距混凝土表面7~9cm处,与同等试验条件下不弯折的钢筋抗浮锚杆相比,极限承载力较大,且破坏特征不同;弯曲处理后的钢筋抗浮锚杆与混凝土之间平均粘结强度随着滑移量的增大而提高,随着外锚固长度的增加而降低,与混凝土之间的平均粘结强度的增加速率随滑移量的增大而减小。
Through specially designed pull-out test,ultimate anti-lifting bearing capacity and slippage of external anchorage(and foundation slab)of some kinds of steel anti-floating anchors were monitored,analyzed their bearing performance and working mechanism.The results show that in the condition of C30 concrete floor,the steel anti-floating anchors with the same diameter and bending radius are fracture failure above the concrete surface 7~9cm in the different vertical anchorage length and bent length,the breaking load of steel anti-floating anchors are over 340 kN,their maximum slippage are 11~21mm,Compared to the straight steel anti-floating anchors at the same condition,the bend anti-floating anchors has higher ultimate anti-lifting bearing capacity and different failure characteristic;the generalized average bond strength between steel anti-floating anchors and concrete enhances with the increase of slippage quantity,and decreases with the increase of external anchorage length.The average bond strength increases rate between steel anti-floating anchors and concrete decreases with the increase of slippage quantity.
Through specially designed pull-out test,ultimate anti-lifting bearing capacity and slippage of external anchorage(and foundation slab)of some kinds of steel anti-floating anchors were monitored,analyzed their bearing performance and working mechanism.The results show that in the condition of C30 concrete floor,the steel anti-floating anchors with the same diameter and bending radius are fracture failure above the concrete surface 7~9cm in the different vertical anchorage length and bent length,the breaking load of steel anti-floating anchors are over 340 kN,their maximum slippage are 11~21mm,Compared to the straight steel anti-floating anchors at the same condition,the bend anti-floating anchors has higher ultimate anti-lifting bearing capacity and different failure characteristic;the generalized average bond strength between steel anti-floating anchors and concrete enhances with the increase of slippage quantity,and decreases with the increase of external anchorage length.The average bond strength increases rate between steel anti-floating anchors and concrete decreases with the increase of slippage quantity.
引文
[1]KOU H,GUO W,ZHANG M.Pullout performance of GFRP anti-floating anchor in weathered soil[J].Tunnelling and Underground Space Technology,2015,49:408-416.
[2]白晓宇,张明义,刘鹤.风化岩地基微型抗浮桩承载性能原位试验研究[J].工业建筑,2014,44(2):94-97.
[3]程良奎,张培文,王帆.岩土锚固工程的若干力学概念问题[J].岩石力学与工程学报,2015,34(4):668-682.
[4]贾金青,宋二祥.滨海大型地下工程抗浮锚杆的设计与试验研究[J].岩土工程学报,2002,24(6):769-771.
[5]付文光,柳建国,杨志银.抗浮锚杆及锚杆抗浮体系稳定性验算公式研究[J].岩土工程学报,2014,36(11):1971-1982.
[6]韩立军,王德亮,渠涛,等.地下大型污水池爆扩抗浮锚固结构设计与应用[J].岩石力学与工程学报,2009,28(增1):2960-2965.
[7]蔡洪伟.抗浮锚杆在某工程设计、施工与验收中的应用[J].地下空间与工程学报,2014,10(增2):1926-1929.
[8]王海东,周亮,曾裕林,等.某地下车库上浮事故分析与加固处理[J].工业建筑,2012,42(3):154-158.
[9]李志军.某医院病房大楼广场地下室上浮原因分析及加固处理[J].中外建筑,2010,10:134-135.
[10]白晓宇.GFRP抗浮锚杆锚固机理试验研究与理论分析[D].青岛理工大学,2015.
[11]MURFF J D,RANDOLPH M F,ELKHATIB S,et al.Vertically loaded plate anchors for deepwater applications[C]//Proc Int Symp on Frontiers in Offshore Geotechnics.2005:31-48.
[12]ANDERSEN K H.DYVIK R.SCHRODER K,et al.1993.Field tests of anchors in clay.II:Predictions and interpretation..Journal of the Geotechnical Engineering Division ASCE,119(10):1532-1549.
[13]SINGH B,DATTA M,GULHATI S K.Pullout behavior of superpile anchors in soft clay under static loading[J].Marine Georesources&Geotechnology,1996,14(3):217-236.
[14]KILIC A,YASAR E,CELIK A G.Effect of grout properties on the pull-out load capacity of fully grouted rock bolt[J].Tunnelling and underground space technology,2002,17(4):355-362.
[15]白晓宇,张明义,刘鹤,等.风化岩地基全螺纹玻璃纤维增强聚合物抗浮锚杆承载特征现场试验[J].岩土力学,2014,35(9):2464-2472.
[16]LUTZ L A,GERGELY P.Mechanics of bond and slip of deformed bars in concrete[J].Journal of American Concrete Institute,1967,64(11):711-721.
[17]HANSON N W.Influence of surface roughness of prestressing strand on bond performance[J].Journal of Prestressed Concrete Institute,1969,14(1):32-45.
[18]GOTO Y.Cracks formed in concrete around deformed tension bars[J].Journal of American Concrete Institute,1971,68(4):244-251.
[19]张明义,白晓宇,李伟伟,等.GFRP抗浮锚杆螺母托盘锚具外锚固性能试验[J].中南大学学报(自然科学版),2016,47(1):239-246.
[20]GB 50152—2012.混凝土结构试验方法标准[S].2012.
[21]JGJ 120—2012.建筑基坑支护技术规程[S].2012
[22]韩军,陈强,刘元坤,等.锚杆灌浆体与岩(土)体间的粘结强度[J].岩石力学与工程学报,2005,24(19):3482-3486.
[23]JGJ 106-2014.建筑基桩检测技术规范[S].2014.
[24]CECS:22—2005岩土锚杆(索)技术规程[S].2005.
[25]张明义,寇海磊,白晓宇,等.玻璃纤维增强聚合物抗浮锚杆抗拔性能试验研究与机制分析[J].岩土力学,2014,35(4):1069-1076.
[26]张明义,张健,刘俊伟,等.中风化花岗岩中抗浮锚杆的试验研究[J].岩石力学与工程学报,2008,27(增刊1):2741-2746.
[27]陈根金.锚杆桩的抗拔试验[J].工程勘察,1997,145(2):15-16.
[28]史佩栋.桩基工程手册:桩和桩基础手册[M].北京:人民交通出版社,2008:161-177.
[2]白晓宇,张明义,刘鹤.风化岩地基微型抗浮桩承载性能原位试验研究[J].工业建筑,2014,44(2):94-97.
[3]程良奎,张培文,王帆.岩土锚固工程的若干力学概念问题[J].岩石力学与工程学报,2015,34(4):668-682.
[4]贾金青,宋二祥.滨海大型地下工程抗浮锚杆的设计与试验研究[J].岩土工程学报,2002,24(6):769-771.
[5]付文光,柳建国,杨志银.抗浮锚杆及锚杆抗浮体系稳定性验算公式研究[J].岩土工程学报,2014,36(11):1971-1982.
[6]韩立军,王德亮,渠涛,等.地下大型污水池爆扩抗浮锚固结构设计与应用[J].岩石力学与工程学报,2009,28(增1):2960-2965.
[7]蔡洪伟.抗浮锚杆在某工程设计、施工与验收中的应用[J].地下空间与工程学报,2014,10(增2):1926-1929.
[8]王海东,周亮,曾裕林,等.某地下车库上浮事故分析与加固处理[J].工业建筑,2012,42(3):154-158.
[9]李志军.某医院病房大楼广场地下室上浮原因分析及加固处理[J].中外建筑,2010,10:134-135.
[10]白晓宇.GFRP抗浮锚杆锚固机理试验研究与理论分析[D].青岛理工大学,2015.
[11]MURFF J D,RANDOLPH M F,ELKHATIB S,et al.Vertically loaded plate anchors for deepwater applications[C]//Proc Int Symp on Frontiers in Offshore Geotechnics.2005:31-48.
[12]ANDERSEN K H.DYVIK R.SCHRODER K,et al.1993.Field tests of anchors in clay.II:Predictions and interpretation..Journal of the Geotechnical Engineering Division ASCE,119(10):1532-1549.
[13]SINGH B,DATTA M,GULHATI S K.Pullout behavior of superpile anchors in soft clay under static loading[J].Marine Georesources&Geotechnology,1996,14(3):217-236.
[14]KILIC A,YASAR E,CELIK A G.Effect of grout properties on the pull-out load capacity of fully grouted rock bolt[J].Tunnelling and underground space technology,2002,17(4):355-362.
[15]白晓宇,张明义,刘鹤,等.风化岩地基全螺纹玻璃纤维增强聚合物抗浮锚杆承载特征现场试验[J].岩土力学,2014,35(9):2464-2472.
[16]LUTZ L A,GERGELY P.Mechanics of bond and slip of deformed bars in concrete[J].Journal of American Concrete Institute,1967,64(11):711-721.
[17]HANSON N W.Influence of surface roughness of prestressing strand on bond performance[J].Journal of Prestressed Concrete Institute,1969,14(1):32-45.
[18]GOTO Y.Cracks formed in concrete around deformed tension bars[J].Journal of American Concrete Institute,1971,68(4):244-251.
[19]张明义,白晓宇,李伟伟,等.GFRP抗浮锚杆螺母托盘锚具外锚固性能试验[J].中南大学学报(自然科学版),2016,47(1):239-246.
[20]GB 50152—2012.混凝土结构试验方法标准[S].2012.
[21]JGJ 120—2012.建筑基坑支护技术规程[S].2012
[22]韩军,陈强,刘元坤,等.锚杆灌浆体与岩(土)体间的粘结强度[J].岩石力学与工程学报,2005,24(19):3482-3486.
[23]JGJ 106-2014.建筑基桩检测技术规范[S].2014.
[24]CECS:22—2005岩土锚杆(索)技术规程[S].2005.
[25]张明义,寇海磊,白晓宇,等.玻璃纤维增强聚合物抗浮锚杆抗拔性能试验研究与机制分析[J].岩土力学,2014,35(4):1069-1076.
[26]张明义,张健,刘俊伟,等.中风化花岗岩中抗浮锚杆的试验研究[J].岩石力学与工程学报,2008,27(增刊1):2741-2746.
[27]陈根金.锚杆桩的抗拔试验[J].工程勘察,1997,145(2):15-16.
[28]史佩栋.桩基工程手册:桩和桩基础手册[M].北京:人民交通出版社,2008:161-177.