底商多层砌体结构抗倒塌加固方法研究
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摘要
由于具有造价低廉，施工技术要求低等优点，砌体结构在我国大部分地区，尤其是中小城镇，得到广泛的应用。但由于砌体结构是采用脆性材料和砂浆两种不同性质的材料砌筑而成的，在随机、往复的地震力作用下，结构极易发生破坏，甚至倒塌，造成巨大的人员伤亡和财产损失。我国南方底商多层砌体房屋存量很大，任何一个地区遭遇汶川那样的地震，后果都不堪想象。从汶川地震中榜样建筑那里学习成功的经验，用于加固既有底商多层砌体，是当前减轻地震灾害的最有效途径之一。
本文在参考大量文献资料的基础上，分析了汶川地震中底商多层砌体结构的震害，提出了基于概念设计的“平衡刚度、增加延性”加固方法，并通过地震模拟振台对比试验对加固效果进行了验证。论文主要成果如下：
1.总结了汶川地震中底商多层砌体结构的结构构造和震害特点。底商多层砌体底层相对空旷，临街侧（前）承重构件一般为混凝土柱、梁或加构造柱的砌体短墙，非临街侧（后）则多为普通砌体；在极震区该类房屋80%以上底层沿纵向倒塌。
2.基于震害和构造分析，认为底层前后纵墙刚度差异大，致使水平地震荷载分配大小不均匀，纵墙被“先后而前”各个击破，而且砌体墙延性不足，开裂后在上部荷载作用下很快崩溃、倒塌。
3.基于上述认识，提出了“前后纵墙平衡刚度、增加后墙延性”的加固方法，通过两组共四个底商砌体结构模型的地震模拟震动台试验，证明所提出的方法能显著提高结构抗倒塌能力。
4.结合实际工程需求，将上述加固方法应用于某多层砌体医院的加固设计中。
Due to the advantages such as low cost and low requirement of constructiontechnology, masonry structure has been popular for many years in China and a lotof developing countries. Because of the britle and low strength of material andcrude structural configuration, masonry is more vulnerable to earthquake. So it ishighly significant to take a thorough and broad study to improve the seismiccapacity of masonry structure especially the frame supported masonry structures.Based on large amounts of technical literature both abroad and domestic. Thispaper analyses the typical damage features of frame supported masonry structuresin WenChuan Earthquake and offers a strengthening method. Through shakingtable contrast test，the reinforcement effect is verified.The main works obtained inthis thesis are as follows：
Firstly the structure construction and earthquake damaga features of framesupported masonry structures in WenChuan earthquake is analyzed.Ground floorof this kind of building is usually with large space,the main load bearingcomponent at the front is RC column,beam and masonry wall with constructionalcolumn,while the main load bearing component at the back is traditional masonrystructure.More than80%of this type of building collapsed in WenChuanearthquake. Based on the analysis of construction and earthquake damagefeatures，the main cause of collapse is the stiffness difference of the front and theback side.The masonry walls at the back side support much of the horizontalseismic force，and because of its low ductility，the walls collapse first then resultin the fracturing of the whole structure.And then, a retrofitting method to proveductility and balance stiffness is offered,through shaking table test,theearthquake-resistance capacity of three kinds of model,viz standard jointsmodel,bad joints model and reinforced model is compared,The conclusion is thatstandard structural joints may improve the ductility of structures,and decrease theprobility of collapse.By adding wing walls and flanking columns,the non-uniformrigidity of bottom frame is meliorated,and the collapse resistance capacity of thebuildings is improved.At last, in combination with the actual engineeringdemand,this method is used in retrofitting of a multi-story masonry hospital.
本文在参考大量文献资料的基础上，分析了汶川地震中底商多层砌体结构的震害，提出了基于概念设计的“平衡刚度、增加延性”加固方法，并通过地震模拟振台对比试验对加固效果进行了验证。论文主要成果如下：
1.总结了汶川地震中底商多层砌体结构的结构构造和震害特点。底商多层砌体底层相对空旷，临街侧（前）承重构件一般为混凝土柱、梁或加构造柱的砌体短墙，非临街侧（后）则多为普通砌体；在极震区该类房屋80%以上底层沿纵向倒塌。
2.基于震害和构造分析，认为底层前后纵墙刚度差异大，致使水平地震荷载分配大小不均匀，纵墙被“先后而前”各个击破，而且砌体墙延性不足，开裂后在上部荷载作用下很快崩溃、倒塌。
3.基于上述认识，提出了“前后纵墙平衡刚度、增加后墙延性”的加固方法，通过两组共四个底商砌体结构模型的地震模拟震动台试验，证明所提出的方法能显著提高结构抗倒塌能力。
4.结合实际工程需求，将上述加固方法应用于某多层砌体医院的加固设计中。
Due to the advantages such as low cost and low requirement of constructiontechnology, masonry structure has been popular for many years in China and a lotof developing countries. Because of the britle and low strength of material andcrude structural configuration, masonry is more vulnerable to earthquake. So it ishighly significant to take a thorough and broad study to improve the seismiccapacity of masonry structure especially the frame supported masonry structures.Based on large amounts of technical literature both abroad and domestic. Thispaper analyses the typical damage features of frame supported masonry structuresin WenChuan Earthquake and offers a strengthening method. Through shakingtable contrast test，the reinforcement effect is verified.The main works obtained inthis thesis are as follows：
Firstly the structure construction and earthquake damaga features of framesupported masonry structures in WenChuan earthquake is analyzed.Ground floorof this kind of building is usually with large space,the main load bearingcomponent at the front is RC column,beam and masonry wall with constructionalcolumn,while the main load bearing component at the back is traditional masonrystructure.More than80%of this type of building collapsed in WenChuanearthquake. Based on the analysis of construction and earthquake damagefeatures，the main cause of collapse is the stiffness difference of the front and theback side.The masonry walls at the back side support much of the horizontalseismic force，and because of its low ductility，the walls collapse first then resultin the fracturing of the whole structure.And then, a retrofitting method to proveductility and balance stiffness is offered,through shaking table test,theearthquake-resistance capacity of three kinds of model,viz standard jointsmodel,bad joints model and reinforced model is compared,The conclusion is thatstandard structural joints may improve the ductility of structures,and decrease theprobility of collapse.By adding wing walls and flanking columns,the non-uniformrigidity of bottom frame is meliorated,and the collapse resistance capacity of thebuildings is improved.At last, in combination with the actual engineeringdemand,this method is used in retrofitting of a multi-story masonry hospital.
引文
[1]丁大钧主编.砌体结构学[M].北京：中国建筑工业出版社，1997.
[2]冯学刚.砌体结构地震破坏模式研究.[D].中国地震局工程力学研究所.2010
[3]郭迅.汶川大地震震害特点与成因分析[J].地震工程与工程振动,2009,29(6):74-87.
[4] GB50011-2010.建筑设计抗震规范[S].
[5] GB50003-2001.砌体结构设计规范[S].
[6] GB50023-2009.建筑抗震鉴定标准.[S].
[7]胡聿贤.地震工程学[M].北京:地震出版社,2006.
[8]黄思凝,袁一凡,孟庆利等.由玉树地震结构震害看村镇房屋抗震[J].世界地震工程,2011,27(2):77-82.
[9]蒋航军,郁银泉.北川地区底部框架砖房震害分析[C].//2008年汶川地震建筑震害分析与重建研讨会论文集.2008:220-226.
[10]贾强,孙剑平.汶川大地震底框结构建筑物震害调查[J].山东建筑大学学报,2008,23(6):560-564.
[11]蒋华.喷射GFRP加固开窗洞无筋砌体墙片抗震性能研究[D].武汉理工大学,2010.
[12]建筑结构补强加固技术编写组.建筑结构补强加固技术.[M].北京:中国铁道出版社，1987
[13]卢先军，王毅红，苏东君等,砌体结构房屋抗震性能评价与加固对策.[J].长安大学学报,2004,3(1):4-7.
[14]刘桂秋.砌体结构基本受力性能的研究[D].湖南大学,2005.
[15]李碧雄,邓建辉,王哲等.5·12汶川地震底框砖房震害启示[J].西安建筑科技大学学报（自然科学版）,2010,42(3):342-347.
[16]欧进萍,王光远.结构随机振动[M].北京:高等教育出版社,1998:221-223.
[17]清华大学,西南交通大学,重庆大学,中国建筑西南设计研究院有限公司,北京市建筑设计研究院.汶川地震建筑震害分析及设计对策[M].北京:中国建筑工业出版社,2009.
[18]孙训方，方孝淑，关来泰编.材料力学I[M].北京:高等教育出版社,2002.
[19]孙景江.建筑结构抗震研究若干基本问题概述及讨论[J].震灾防御技术,2006,1(2):87-96.
[20]石亦平,周玉蓉.ABAQUS有限元分析实例详解[M].北京:机械工业出版社,2006.
[21]唐岱新主编.砌体结构[M].北京：高等教育出版社，2003.
[22]夏云霞.砌体结构窗下墙的震害机理研究.[D].中国地震局工程力学研究所.2011.
[23]徐有邻.汶川地震震害调查及对建筑结构安全的反思.[M].北京:中国建筑工业出版社.2009.
[24]谢礼立,吕大刚等译.结构动力学理论及其在地震工程中的应用(第二版)[M].北京:高等教育出版社.
[25]张敏政.汶川地震中都江堰市的房屋震害[J].地震工程与工程振动.2008，23(3):1-6.
[26]张敏政.地震模拟实验中相似律应用的若干问题[J].地震工程与工程振动，1997，17(2):52-58.
[27]张敏政等.建筑结构的地震模拟实验研究[J].工程抗震，2003，(4):31-35.
[28]郑怡，张耀庭.汶川地震主要建筑物震害调查及思考.[J].华中科技大学学报（城市科学版）,2009,26(2):95-98,102.
[29]周炳章.砌体房屋抗震设计.[M].北京：地震出版社，1991.
[30]周德源,程才渊,吴明舜.砌体结构抗震设计[M].武汉:武汉理工大学出版社,2004.
[31] Anil K. Chopra. Dynamics of Structures-Theory and Applications to EarthquakeEngineering [M]. Beijing: Thinghua University Press,2005.
[32] T.Paulay, M.J.N.Priestley. Seismic Design of Reinforced Concrete and MasonryBuildings [M]. New York:Jone Wiley&Sons, Inc,1992.
[33] G.W.Housner, P.C.Jennings.Earthquake Design Criteria[M].Earthquake EngineeringResearch Institute.
[34] Turel Gur,Ali Cihan Pay.Performance of School Building in Turkey During the1999Duzce and the2003Bingol Earthquakes[J],Earthquake Spectra.Vol.25No.2May.2009.
[2]冯学刚.砌体结构地震破坏模式研究.[D].中国地震局工程力学研究所.2010
[3]郭迅.汶川大地震震害特点与成因分析[J].地震工程与工程振动,2009,29(6):74-87.
[4] GB50011-2010.建筑设计抗震规范[S].
[5] GB50003-2001.砌体结构设计规范[S].
[6] GB50023-2009.建筑抗震鉴定标准.[S].
[7]胡聿贤.地震工程学[M].北京:地震出版社,2006.
[8]黄思凝,袁一凡,孟庆利等.由玉树地震结构震害看村镇房屋抗震[J].世界地震工程,2011,27(2):77-82.
[9]蒋航军,郁银泉.北川地区底部框架砖房震害分析[C].//2008年汶川地震建筑震害分析与重建研讨会论文集.2008:220-226.
[10]贾强,孙剑平.汶川大地震底框结构建筑物震害调查[J].山东建筑大学学报,2008,23(6):560-564.
[11]蒋华.喷射GFRP加固开窗洞无筋砌体墙片抗震性能研究[D].武汉理工大学,2010.
[12]建筑结构补强加固技术编写组.建筑结构补强加固技术.[M].北京:中国铁道出版社，1987
[13]卢先军，王毅红，苏东君等,砌体结构房屋抗震性能评价与加固对策.[J].长安大学学报,2004,3(1):4-7.
[14]刘桂秋.砌体结构基本受力性能的研究[D].湖南大学,2005.
[15]李碧雄,邓建辉,王哲等.5·12汶川地震底框砖房震害启示[J].西安建筑科技大学学报（自然科学版）,2010,42(3):342-347.
[16]欧进萍,王光远.结构随机振动[M].北京:高等教育出版社,1998:221-223.
[17]清华大学,西南交通大学,重庆大学,中国建筑西南设计研究院有限公司,北京市建筑设计研究院.汶川地震建筑震害分析及设计对策[M].北京:中国建筑工业出版社,2009.
[18]孙训方，方孝淑，关来泰编.材料力学I[M].北京:高等教育出版社,2002.
[19]孙景江.建筑结构抗震研究若干基本问题概述及讨论[J].震灾防御技术,2006,1(2):87-96.
[20]石亦平,周玉蓉.ABAQUS有限元分析实例详解[M].北京:机械工业出版社,2006.
[21]唐岱新主编.砌体结构[M].北京：高等教育出版社，2003.
[22]夏云霞.砌体结构窗下墙的震害机理研究.[D].中国地震局工程力学研究所.2011.
[23]徐有邻.汶川地震震害调查及对建筑结构安全的反思.[M].北京:中国建筑工业出版社.2009.
[24]谢礼立,吕大刚等译.结构动力学理论及其在地震工程中的应用(第二版)[M].北京:高等教育出版社.
[25]张敏政.汶川地震中都江堰市的房屋震害[J].地震工程与工程振动.2008，23(3):1-6.
[26]张敏政.地震模拟实验中相似律应用的若干问题[J].地震工程与工程振动，1997，17(2):52-58.
[27]张敏政等.建筑结构的地震模拟实验研究[J].工程抗震，2003，(4):31-35.
[28]郑怡，张耀庭.汶川地震主要建筑物震害调查及思考.[J].华中科技大学学报（城市科学版）,2009,26(2):95-98,102.
[29]周炳章.砌体房屋抗震设计.[M].北京：地震出版社，1991.
[30]周德源,程才渊,吴明舜.砌体结构抗震设计[M].武汉:武汉理工大学出版社,2004.
[31] Anil K. Chopra. Dynamics of Structures-Theory and Applications to EarthquakeEngineering [M]. Beijing: Thinghua University Press,2005.
[32] T.Paulay, M.J.N.Priestley. Seismic Design of Reinforced Concrete and MasonryBuildings [M]. New York:Jone Wiley&Sons, Inc,1992.
[33] G.W.Housner, P.C.Jennings.Earthquake Design Criteria[M].Earthquake EngineeringResearch Institute.
[34] Turel Gur,Ali Cihan Pay.Performance of School Building in Turkey During the1999Duzce and the2003Bingol Earthquakes[J],Earthquake Spectra.Vol.25No.2May.2009.