间断式横缝设计及其对大坝地震响应的影响
|
摘要
介绍强震区高碾压混凝土重力坝横缝的创新性设计及其对大坝地震响应的影响。为提高大坝的整体稳定性,对坝体每一碾压浇筑层,横缝的切缝深度仅切割2/3浇筑层厚度,并在切缝中填充无纺布,使横缝具有弱连接诱导缝的性质,达到既能满足温控要求,又可增强大坝的整体性。开发了反映横缝法向开合非线性和径向滑移动接触模型,采用非线性指数型动接触本构模型模拟了横缝的张开、闭合的非线性力学行为,运用摩尔库伦定律模拟了横缝的切向非线性特性。对在建的金安桥碾压混凝土重力坝3条横缝、10条横缝的情形分别进行了地震响应分析。结果表明,间断式横缝有效地提高了大坝的整体性,大坝横河向位移响应明显减小;金安桥大坝靠左右岸坝段的横缝的张开度明显大于中间坝段横缝的开度值,相应的张开-闭合频率也远高于中间坝段的横缝。所提设计方案已用于实际工程,实践表明具有较好的效果,可推广用于类似碾压混凝土大坝的施工设计。
An innovative design of transverse joint of high RCC gravity dam in high-intensity earthquake region and its effects on the seismic response of the dam are presented in the paper.To improve the whole stability of the dam,the cutting depth is only 2 /3 of the lift thickness for each rolled concrete layer,and the cutting joints are filled with non-woven fabrics so as to possess the features of weak-link induced joints.Thus,the transverse joints not only meet the temperature control requirements,but also improve the integrity of dam.A nonlinear exponential dynamic contact model of normal opening-closing and a nonlinear radial slide model based on Mohr-Coulomb law are developed for the contact of transverse joints.By using these models,a seismic analysis of the Jin-anqiao RCC gravity dam under construction is carried out for the schemes of 3 joints and 10 joints,respectively.The results show that the new design of transverse joints improves the dam integrity effectively and reduces the displacements in across river direction considerably.The joint openings near the left and right banks of this dam are considerably greater than that of the middle section;the corresponding opening-closing frequency is much higher than that of the middle section.The joint design has been adopted in practice,and the applications show a good effect of the proposed joints.It could be applied to the similar RCC dams.
An innovative design of transverse joint of high RCC gravity dam in high-intensity earthquake region and its effects on the seismic response of the dam are presented in the paper.To improve the whole stability of the dam,the cutting depth is only 2 /3 of the lift thickness for each rolled concrete layer,and the cutting joints are filled with non-woven fabrics so as to possess the features of weak-link induced joints.Thus,the transverse joints not only meet the temperature control requirements,but also improve the integrity of dam.A nonlinear exponential dynamic contact model of normal opening-closing and a nonlinear radial slide model based on Mohr-Coulomb law are developed for the contact of transverse joints.By using these models,a seismic analysis of the Jin-anqiao RCC gravity dam under construction is carried out for the schemes of 3 joints and 10 joints,respectively.The results show that the new design of transverse joints improves the dam integrity effectively and reduces the displacements in across river direction considerably.The joint openings near the left and right banks of this dam are considerably greater than that of the middle section;the corresponding opening-closing frequency is much higher than that of the middle section.The joint design has been adopted in practice,and the applications show a good effect of the proposed joints.It could be applied to the similar RCC dams.
引文
[1]孙君森,林鸿镁.重力坝设计新思路[J].水利学报,2004,35(2):62～67.Sun Junsen,Lin Hongmei.New design philosophy for gravity dams[J].Journal of Hydraulic Engineering,2004,35(2):62-67.(in Chinese)
[2]丁汉涛.碾压混凝土坝横缝的新型结构——间断缝初探[J].水利水电技术,1990,21(2):23～25.Ding Hantao.Preliminary study on the discontinuous joint——a new structure of transverse joint of RCC dam[J].Water Resourcesand Hydropower Engineering,1990,21(2):23～25.(in Chinese)
[3]陈秋华.碾压混凝土拱坝成缝新技术[J].水力发电,2002,28(1):23～26.Chen Qiuhua.The new joint-forming technique of RCC arch dam[J].Water power,2002,28(1):23～26.(in Chinese)
[4]杨家修,崔进,张世杰.龙首水电站碾压混凝土拱坝结构设计[J].水力发电,2001,27(10):15-17.Yang Jiaxiu,Cui Jin,Zhang Shijie.Structural design of the RCC arch dam for Longshou hydropower station[J].Water power,2001,27(10):15～17.(in Chinese)
[5]陈秋华,丁予通.沙牌碾压混凝土拱坝结构分缝设计研究[J].水电站设计,2002,18(1):21～25.Chen Qiuhua,Ding Yutong.Structure jointing design research on Shapai Roller compacted concrete arch dam[J].Design ofHydroelectric Power Station,2002,18(1):21～25.(in Chinese)
[6]黄宜胜,常晓林,李建林.切割式横缝碾压混凝土重力坝抗震安全性研究[J].岩土力学,2008,28(增):47～51.Huang Yisheng,Chang Xiaolin,Li Jianlin.Aseismic safety research on RCC gravity dam with incised transverse joint[J].Rockand Soil Mechanics,2008,28(suup.):47～51.(in Chinese)
[7]洪永文.金安桥水电站碾压混凝土重力坝设计[J].水力发电,2006,32(11):54～56.Hong Yongwen.Design of RCC gravity dam of Jin-anqiao hydropower station[J].Water power,2006,32(11):54～56.(inChinese)
[8]龙渝川,周元德,张楚汉.基于两类横缝接触模型的拱坝非线性动力响应研究[J].水利学报,2005,36(9):1094～1099.Long Yuchuan,Zhou Yuande,Zhang Chuhan.A comparison study of nonlinear dynamic responses of arch dams based on two typesof contraction joint models[J].Journal of Hydraulic Engineering,2005,36(9):1094～1099.(in Chinese)
[9]江守燕,杜成斌,陈灯红.考虑横缝键槽咬合的拱坝地震响应分析[J].防灾减灾工程学报,2010,30(2):177～184.Jiang Shouyan,Du Chengbin,Chen Denghong.Seismic response analysis of arch dam with key slots occlusion[J].Journal ofDisaster Prevent and Mitigation Engineering,2010,30(2):177～184.(in Chinese)
[10]Zhang Chuhan,Pan Jianwen,Wang Jinting.Influence of seismic input mechanisms and radiation damping on arch dam response[J].Soil Dynamics and Earthquake Engineering,2009,29(9):1282～1293.
[11]杜成斌,洪永文,孙立国,等.金安桥水电站工程碾压混凝土重力坝动力学分析及抗震安全性评价[R].南京:河海大学,2008.Du Chengbin,Hong Yongwen,Sun Liguo,et al.Dynamic Analysis and Seismic Safety Evaluation of RCC Gravity Dam of Jin-anqiaoHydropower Project[R].Nanjing:Hohai University,2008.(in Chinese)
[2]丁汉涛.碾压混凝土坝横缝的新型结构——间断缝初探[J].水利水电技术,1990,21(2):23～25.Ding Hantao.Preliminary study on the discontinuous joint——a new structure of transverse joint of RCC dam[J].Water Resourcesand Hydropower Engineering,1990,21(2):23～25.(in Chinese)
[3]陈秋华.碾压混凝土拱坝成缝新技术[J].水力发电,2002,28(1):23～26.Chen Qiuhua.The new joint-forming technique of RCC arch dam[J].Water power,2002,28(1):23～26.(in Chinese)
[4]杨家修,崔进,张世杰.龙首水电站碾压混凝土拱坝结构设计[J].水力发电,2001,27(10):15-17.Yang Jiaxiu,Cui Jin,Zhang Shijie.Structural design of the RCC arch dam for Longshou hydropower station[J].Water power,2001,27(10):15～17.(in Chinese)
[5]陈秋华,丁予通.沙牌碾压混凝土拱坝结构分缝设计研究[J].水电站设计,2002,18(1):21～25.Chen Qiuhua,Ding Yutong.Structure jointing design research on Shapai Roller compacted concrete arch dam[J].Design ofHydroelectric Power Station,2002,18(1):21～25.(in Chinese)
[6]黄宜胜,常晓林,李建林.切割式横缝碾压混凝土重力坝抗震安全性研究[J].岩土力学,2008,28(增):47～51.Huang Yisheng,Chang Xiaolin,Li Jianlin.Aseismic safety research on RCC gravity dam with incised transverse joint[J].Rockand Soil Mechanics,2008,28(suup.):47～51.(in Chinese)
[7]洪永文.金安桥水电站碾压混凝土重力坝设计[J].水力发电,2006,32(11):54～56.Hong Yongwen.Design of RCC gravity dam of Jin-anqiao hydropower station[J].Water power,2006,32(11):54～56.(inChinese)
[8]龙渝川,周元德,张楚汉.基于两类横缝接触模型的拱坝非线性动力响应研究[J].水利学报,2005,36(9):1094～1099.Long Yuchuan,Zhou Yuande,Zhang Chuhan.A comparison study of nonlinear dynamic responses of arch dams based on two typesof contraction joint models[J].Journal of Hydraulic Engineering,2005,36(9):1094～1099.(in Chinese)
[9]江守燕,杜成斌,陈灯红.考虑横缝键槽咬合的拱坝地震响应分析[J].防灾减灾工程学报,2010,30(2):177～184.Jiang Shouyan,Du Chengbin,Chen Denghong.Seismic response analysis of arch dam with key slots occlusion[J].Journal ofDisaster Prevent and Mitigation Engineering,2010,30(2):177～184.(in Chinese)
[10]Zhang Chuhan,Pan Jianwen,Wang Jinting.Influence of seismic input mechanisms and radiation damping on arch dam response[J].Soil Dynamics and Earthquake Engineering,2009,29(9):1282～1293.
[11]杜成斌,洪永文,孙立国,等.金安桥水电站工程碾压混凝土重力坝动力学分析及抗震安全性评价[R].南京:河海大学,2008.Du Chengbin,Hong Yongwen,Sun Liguo,et al.Dynamic Analysis and Seismic Safety Evaluation of RCC Gravity Dam of Jin-anqiaoHydropower Project[R].Nanjing:Hohai University,2008.(in Chinese)
版权所有：© 2023 中国地质图书馆 中国地质调查局地学文献中心