【摘要】：為了給大跨度斜拉橋邊墩橫向抗震體系設計提供依據(jù),討論了減震體系的合理性,并研究了減震體系的適用范圍。首先,針對橫向全滑動體系,分析了梁端橫向位移的控制振型,推導了邊跨主梁橫向基本周期的簡化計算公式,并利用反應譜法,推導與簡化了地震下梁端橫向位移的計算公式,通過與有限元計算結果對比,驗證了其可靠性。然后,依據(jù)實際項目工程經(jīng)驗,通過合理簡化與假定斜拉橋結構參數(shù),在工程精度允許范圍內(nèi),進一步對計算公式進行簡化。最后,以主跨跨徑與地震動輸入為主要變量進行共計384個工況的計算,分析了各工況下梁端最大橫向位移,得到了不同跨徑下橫向全滑動體系斜拉橋在不同場地類型與不同峰值加速度(PGA)下的梁端最大橫向位移變化規(guī)律。研究結果表明:以梁端橫向位移為抗震目標時,對于Ⅲ,Ⅳ類場地,各PGA作用下,主跨跨徑大于400m的斜拉橋均需考慮采用減震體系;對于Ⅰ,Ⅱ類場地,PGA不大于0.1g,主跨跨徑不大于600m的斜拉橋可以不考慮采用減震體系;其中,如果結構的抗震能力大于地震需求,建議采用全限位體系;如果結構的抗震能力接近或小于地震需求,且梁端橫向位移不控制時,則建議采用全滑動體系。
[Abstract]:In order to provide the basis for the design of lateral seismic system of side pier of long-span cable-stayed bridge, the rationality of the system is discussed, and the applicable range of the system is studied. First of all, the control mode of transverse displacement of beam end is analyzed, and the simplified calculation formula of lateral basic period of side span main beam is deduced, and the response spectrum method is used. The calculation formula of transverse displacement of beam end under earthquake is deduced and simplified, and its reliability is verified by comparing with the results of finite element calculation. Then, according to the actual project engineering experience, the calculation formula is further simplified by reasonably simplifying and assuming the structural parameters of cable-stayed bridge and within the scope of engineering accuracy. Finally, the main span and the input of ground motion are taken as the main variables to calculate a total of 384 working conditions, and the maximum transverse displacement of the end of the beam under each working condition is analyzed. The variation of maximum transverse displacement at the beam end of the cable-stayed bridge with transverse sliding system under different spans under different site types and different peak acceleration (PGA) is obtained. The results show that when the transverse displacement of the beam end is taken as the seismic target, for the sites of type 鈪，

本文編號：2249791