地连墙-重力式复合锚碇基础承载性能试验研究
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摘要
为研究地连墙-重力式复合锚碇基础底板以下地连墙嵌固作用对其承载性能的影响,依托西江特大桥清远侧新型地连墙锚碇设计方案,分别开展相同试验条件下地连墙-重力式复合锚碇基础与不考虑地连墙嵌固效应的常规锚碇基础两组物理模型试验,对荷载与位移关系、基底土压力分布及荷载分配规律进行分析。结果表明:与常规锚碇相比,由于地连墙嵌入深部中分化基岩,地连墙-重力式复合锚碇基础可充分发挥嵌岩地连墙强度及深层岩体承载能力,在竖向荷载和水平荷载作用下,地连墙-重力式复合锚碇基础竖向位移和水平位移均明显小于无嵌岩地连墙的常规锚碇基础,其中设计缆力条件下可降低水平位移量75%左右,表明嵌岩地连墙结构有效提高了锚碇基础承载性能和安全储备。由土压力及荷载分配规律可知,上部竖向荷载通过地连墙结构传递到深部基岩,有效分担了基础底板土体压应力,进而降低地基土体附加应力和基础沉降量。综合表明,当地连墙结构嵌入深部强度较好的基岩时,采用地连墙作为基坑围护结构的锚碇基础设计可考虑地连墙嵌固作用对其承载力的贡献。
To study the influence of the embedding action of diaphragm wall below the bottom of diaphragm wall-gravity anchorage composite foundation on its bearing capacity, two sets of physical model tests of the underground diaphragm wall-anchor combined foundation and the conventional anchor foundation without considering the embedding effect of diaphragm wall-were carried out under the same conditions, relying on the design scheme of new diaphragm wall anchorage at Qingyuan side of Xijiang Super Bridge.The relationship between load and displacement, the distribution of soil pressure and the load distribution are analyzed. The results show that the vertical displacement and horizontal displacement of the combined anchor foundation are obviously smaller than that of the conventional anchor foundation due to the consolidation and fixed effect of the diaphragm wall under the vertical and horizontal loads. Compared with the conventional anchorage, diaphragm wall-gravity type composite anchorage foundation can make full use of diaphragm strength embedded into rock and bearing capacity of deep rock mass. The horizontal displacement can be reduced by about 75% under the design of cable force, which effectively improve the bearing and safety performance. The vertical load can transfer from the ground wall structure to the deep bedrock, which can share the soil pressure on the foundation base, and reduce additional stress and settlement, according to the soil pressure and load distribution law. The comprehensive analysis shows that the contribution for bearing capacity of ground diaphragm wall designed as the anchorage foundation of the retaining structure can be considered in design, when the bottom of underground diaphragm wall is embedded into bedrock.
To study the influence of the embedding action of diaphragm wall below the bottom of diaphragm wall-gravity anchorage composite foundation on its bearing capacity, two sets of physical model tests of the underground diaphragm wall-anchor combined foundation and the conventional anchor foundation without considering the embedding effect of diaphragm wall-were carried out under the same conditions, relying on the design scheme of new diaphragm wall anchorage at Qingyuan side of Xijiang Super Bridge.The relationship between load and displacement, the distribution of soil pressure and the load distribution are analyzed. The results show that the vertical displacement and horizontal displacement of the combined anchor foundation are obviously smaller than that of the conventional anchor foundation due to the consolidation and fixed effect of the diaphragm wall under the vertical and horizontal loads. Compared with the conventional anchorage, diaphragm wall-gravity type composite anchorage foundation can make full use of diaphragm strength embedded into rock and bearing capacity of deep rock mass. The horizontal displacement can be reduced by about 75% under the design of cable force, which effectively improve the bearing and safety performance. The vertical load can transfer from the ground wall structure to the deep bedrock, which can share the soil pressure on the foundation base, and reduce additional stress and settlement, according to the soil pressure and load distribution law. The comprehensive analysis shows that the contribution for bearing capacity of ground diaphragm wall designed as the anchorage foundation of the retaining structure can be considered in design, when the bottom of underground diaphragm wall is embedded into bedrock.
引文
[1]BRUCE D A,CHAN P H C,TAMARA G J.Design construction and performance of a deep circular diaphragm wall[J].ASTM Special Technical Publication,1992(1129):391-402.
[2]KUSAKABE O,MURATA O,ARIA Y.A numerical study on ground displacement and stress during and after the installation of deep circular diaphragm walls and soil excavation[J].Computers and Geotechnics,2008(35):791-807.
[3]HSIEN C Y,OU P G.Characteristics of ground surface settlement during excavation Can[J].Geotechnical,1993,68(3):30-33.
[4]LONG M.Database for retaining wall and ground movements due to deep excavations[J].Journal of Geotechnical and Geoenvironmental Engineering,2001,127(3):203-224.
[5]PIPINATO A.Innovative bridge design handbook construction,rehabilitation and maintenance[M].[S.l.]:Elsevier Inc,2016.
[6]加岛聪,佐野幸洋,古屋信明,等.明石海峡大桥1号锚墩的设计与施工[J].国外桥梁,1993(3):213-221.KAJIMA So,SANO Yukihiro,FURUYA Nobuki,et al.Design and construction of the Akashi Kaikyo Bridge No.1 anchor pie[J].World Bridges,1993(3):213-221.
[7]夏才初,程鸿鑫,李荣强.广东虎门大桥东锚碇现场结构模型试验研究[J].岩石力学与工程学报,1997,16(6):571-576.XIA Cai-chu,CHENG Hong-xin,LI Rong-qiang.Testing study on field structure model of the east anchorage of Guangdong Humen bridge[J].Chinese Journal of Rock Mechanics and Engineering,1997,16(6):571-576.
[8]李家平,张子新,黄宏伟,等.宁波庆丰大桥锚碇室内相似模型试验研究[J].同济大学学报(自然科学版),2005,33(8):1011-1016.LI Jia-ping,ZHANG Zi-xin,HUANG Hong-wei,et al.Research on similarity model test of anchorage of Qingfeng suspension bridge in Ningbo[J].Journal of Tongji University(Natural Science),2005,33(8):1011-1016.
[9]李家平,李永盛,王如路.悬索桥重力式锚碇结构变位规律研究[J].岩土力学,2007,28(1):145-150.LI Jia-ping,LI Yong-sheng,WANG Ru-lu.Research on displacement of anchorage of suspension bridge[J].Rock and Soil Mechanics,2007,28(1):145-150.
[10]崖岗,韩冬冬,石海洋,等.虎门二桥坭洲水道桥重力式锚碇基础稳定性研究[J].公路,2017(4):129-134.YA Gang,HAN Dong-dong,SHI Hai-yang,et al.Research on gravity anchor foundation stability of Nizhou waterway bridge in Humen bridge[J].Highway,2017(4):129-134.
[11]崖岗,王旭东,鲜荣,等.悬索桥地下连续墙-锚碇复合基础协同承载特征分析[J].公路,2017(1):106-111.YA Gang,WANG Xu-dong,XIAN Rong,et al.Numerical simulation of the bearing mechanics of underground diaphragm wall-anchor combined foundation[J].Highway,2017(1):106-111.
[12]李永盛.江阴长江公路大桥北锚碇模型试验研究[J].同济大学学报,1995,23(2):134-140.LI Yong-sheng.Experimental study on the North anchorage of the Jiangyin Yangtze bridge[J].Journal of Tongji University,1995,23(2):134-140.
[13]林荣安.悬索桥重力式锚碇系统受力分析及其优化[D].西安:长安大学,2008.LIN Rong-an.Analyzing and optimizing the bearing behaviors of gravity anchorage system for suspension bridge[D].Xi’an:Chang’an University,2008.
[14]朱晓文,赵启林,朱凯,等.润扬大桥北锚碇基础三维数值仿真分析[J].东南大学学报(自然科学版),2005,35(2):293-297.ZHU Xiao-wen,ZHAO Qi-lin,ZHU Kai,et al.3-Dsimulation analysis of Runyang suspended bridge’s north anchorage[J].Journal of Southeast University(Natural Science Edition),2005,35(2):293-297.
[15]范菊.悬索桥锚碇系统及接触摩擦问题的研究[D].大连:大连理工大学,2011.FAN Ju.The study of suspension bridge anchorage system and the question of contact friction[D].Dalian:Dalian University of Technology,2011.
[16]魏焕卫,孙川,王建强,等.堆载下桩+地下墙水平承载组合基础模型试验研究[J].岩土力学,2018,39(增刊1):203-210.WEI Huan-wei,SUN Chuan,WANG Jian-qiang,et al.Model test of combined foundation of piles-diaphragm wall under surcharge[J].Rock and Soil Mechanics,2018,39(Suppl.1):203-210.
[17]刘红军,张浩,李洪江,等.软黏土中伞式吸力锚基础水平承载有限元分析[J].岩土力学,2017,38(11):3325-3331.LIU Hong-jun,ZHANG Hao,LI Hong-jiang,et al.Finite element analysis of horizontal bearing capacity of umbrella suction anchor foundation in soft clay[J].Rock and Soil Mechanics,2017,38(11):3325-3331.
[18]过超,龚维明,徐国平,等.逆作复合桩基承载性能试验研究[J].岩土工程学报,2010,32(6):843-849.GUO Chao,GONG Wei-ming,XU Guo-ping,et al.Experimental research on load-carrying properties of composite foundation in top-down order[J].Chinese Journal of Geotechnical Engineering,2010,32(6):843-849.
[19]过超,付佰勇,袁洪,等.桥梁逆作承台-群桩复合基础应用与现场实测研究[J].岩土工程学报,2016,3(11):2085-2092.GUO Chao,FU Bai-yong,YUAN Hong,et al.Application and field tests of cap-pile combined foundation with reversed construction[J].Chinese Journal of Geotechnical Engineering,2016,3(11):2085-2092.
[20]中国电力企业联合会.GB/T 50266―2013工程岩体试验方法标准[S].北京:中国计划出版社,2013.China Electricity Council.GB/T 50266―2013 Standard for test methods of engineering rock mass[S].Beijing:China Planning Press,2013.
[2]KUSAKABE O,MURATA O,ARIA Y.A numerical study on ground displacement and stress during and after the installation of deep circular diaphragm walls and soil excavation[J].Computers and Geotechnics,2008(35):791-807.
[3]HSIEN C Y,OU P G.Characteristics of ground surface settlement during excavation Can[J].Geotechnical,1993,68(3):30-33.
[4]LONG M.Database for retaining wall and ground movements due to deep excavations[J].Journal of Geotechnical and Geoenvironmental Engineering,2001,127(3):203-224.
[5]PIPINATO A.Innovative bridge design handbook construction,rehabilitation and maintenance[M].[S.l.]:Elsevier Inc,2016.
[6]加岛聪,佐野幸洋,古屋信明,等.明石海峡大桥1号锚墩的设计与施工[J].国外桥梁,1993(3):213-221.KAJIMA So,SANO Yukihiro,FURUYA Nobuki,et al.Design and construction of the Akashi Kaikyo Bridge No.1 anchor pie[J].World Bridges,1993(3):213-221.
[7]夏才初,程鸿鑫,李荣强.广东虎门大桥东锚碇现场结构模型试验研究[J].岩石力学与工程学报,1997,16(6):571-576.XIA Cai-chu,CHENG Hong-xin,LI Rong-qiang.Testing study on field structure model of the east anchorage of Guangdong Humen bridge[J].Chinese Journal of Rock Mechanics and Engineering,1997,16(6):571-576.
[8]李家平,张子新,黄宏伟,等.宁波庆丰大桥锚碇室内相似模型试验研究[J].同济大学学报(自然科学版),2005,33(8):1011-1016.LI Jia-ping,ZHANG Zi-xin,HUANG Hong-wei,et al.Research on similarity model test of anchorage of Qingfeng suspension bridge in Ningbo[J].Journal of Tongji University(Natural Science),2005,33(8):1011-1016.
[9]李家平,李永盛,王如路.悬索桥重力式锚碇结构变位规律研究[J].岩土力学,2007,28(1):145-150.LI Jia-ping,LI Yong-sheng,WANG Ru-lu.Research on displacement of anchorage of suspension bridge[J].Rock and Soil Mechanics,2007,28(1):145-150.
[10]崖岗,韩冬冬,石海洋,等.虎门二桥坭洲水道桥重力式锚碇基础稳定性研究[J].公路,2017(4):129-134.YA Gang,HAN Dong-dong,SHI Hai-yang,et al.Research on gravity anchor foundation stability of Nizhou waterway bridge in Humen bridge[J].Highway,2017(4):129-134.
[11]崖岗,王旭东,鲜荣,等.悬索桥地下连续墙-锚碇复合基础协同承载特征分析[J].公路,2017(1):106-111.YA Gang,WANG Xu-dong,XIAN Rong,et al.Numerical simulation of the bearing mechanics of underground diaphragm wall-anchor combined foundation[J].Highway,2017(1):106-111.
[12]李永盛.江阴长江公路大桥北锚碇模型试验研究[J].同济大学学报,1995,23(2):134-140.LI Yong-sheng.Experimental study on the North anchorage of the Jiangyin Yangtze bridge[J].Journal of Tongji University,1995,23(2):134-140.
[13]林荣安.悬索桥重力式锚碇系统受力分析及其优化[D].西安:长安大学,2008.LIN Rong-an.Analyzing and optimizing the bearing behaviors of gravity anchorage system for suspension bridge[D].Xi’an:Chang’an University,2008.
[14]朱晓文,赵启林,朱凯,等.润扬大桥北锚碇基础三维数值仿真分析[J].东南大学学报(自然科学版),2005,35(2):293-297.ZHU Xiao-wen,ZHAO Qi-lin,ZHU Kai,et al.3-Dsimulation analysis of Runyang suspended bridge’s north anchorage[J].Journal of Southeast University(Natural Science Edition),2005,35(2):293-297.
[15]范菊.悬索桥锚碇系统及接触摩擦问题的研究[D].大连:大连理工大学,2011.FAN Ju.The study of suspension bridge anchorage system and the question of contact friction[D].Dalian:Dalian University of Technology,2011.
[16]魏焕卫,孙川,王建强,等.堆载下桩+地下墙水平承载组合基础模型试验研究[J].岩土力学,2018,39(增刊1):203-210.WEI Huan-wei,SUN Chuan,WANG Jian-qiang,et al.Model test of combined foundation of piles-diaphragm wall under surcharge[J].Rock and Soil Mechanics,2018,39(Suppl.1):203-210.
[17]刘红军,张浩,李洪江,等.软黏土中伞式吸力锚基础水平承载有限元分析[J].岩土力学,2017,38(11):3325-3331.LIU Hong-jun,ZHANG Hao,LI Hong-jiang,et al.Finite element analysis of horizontal bearing capacity of umbrella suction anchor foundation in soft clay[J].Rock and Soil Mechanics,2017,38(11):3325-3331.
[18]过超,龚维明,徐国平,等.逆作复合桩基承载性能试验研究[J].岩土工程学报,2010,32(6):843-849.GUO Chao,GONG Wei-ming,XU Guo-ping,et al.Experimental research on load-carrying properties of composite foundation in top-down order[J].Chinese Journal of Geotechnical Engineering,2010,32(6):843-849.
[19]过超,付佰勇,袁洪,等.桥梁逆作承台-群桩复合基础应用与现场实测研究[J].岩土工程学报,2016,3(11):2085-2092.GUO Chao,FU Bai-yong,YUAN Hong,et al.Application and field tests of cap-pile combined foundation with reversed construction[J].Chinese Journal of Geotechnical Engineering,2016,3(11):2085-2092.
[20]中国电力企业联合会.GB/T 50266―2013工程岩体试验方法标准[S].北京:中国计划出版社,2013.China Electricity Council.GB/T 50266―2013 Standard for test methods of engineering rock mass[S].Beijing:China Planning Press,2013.