振动与冲击
振動與遲擊
진동여충격
JOURNAL OF VIBRATION AND SHOCK
2014年
1期
154-161
,共8页
残余位移%峰值位移%P-Δ效应%屈服后刚度比%规一化屈服强度
殘餘位移%峰值位移%P-Δ效應%屈服後剛度比%規一化屈服彊度
잔여위이%봉치위이%P-Δ효응%굴복후강도비%규일화굴복강도
residual displacement%peak displacement%P-Δ effect%post-yield stiffness ratio%normalized yield strength
残余位移是评价桥梁结构震后可修复性和可用性的重要指标,而P-Δ效应对桥梁结构的残余位移影响显著。综合考虑P-Δ效应和地震动随机特性的影响,通过大量的非弹性动力时程分析,定量地分析桥梁结构震后残余位移的概率统计特征和经验预测方程。首先根据动力平衡原理,建立考虑P-Δ效应的桥梁结构非弹性地震动力响应分析的运动控制微分方程,然后结合所筛选的69条强震记录,利用概率统计方法定量地分析P-Δ效应、屈服后刚度比、规一化屈服强度和自振周期等因素对震后残余位移的概率统计特征的影响,进而对残余位移与峰值位移之间的相关性进行讨论,并建立残余位移与峰值位移之间的经验预测方程。分析结果表明:P-Δ效应、屈服后刚度比和规一化屈服强度对残余位移的均值影响较大,而对残余位移的变异性影响相对较小;桥梁结构的震后残余位移可以描述为对数正态分布或威布尔分布随机变量;残余位移与峰值位移之间具有较强的相关性,且二者比值的均值(变异系数)随着自振周期和稳定系数的增大而增大(减小)。
殘餘位移是評價橋樑結構震後可脩複性和可用性的重要指標,而P-Δ效應對橋樑結構的殘餘位移影響顯著。綜閤攷慮P-Δ效應和地震動隨機特性的影響,通過大量的非彈性動力時程分析,定量地分析橋樑結構震後殘餘位移的概率統計特徵和經驗預測方程。首先根據動力平衡原理,建立攷慮P-Δ效應的橋樑結構非彈性地震動力響應分析的運動控製微分方程,然後結閤所篩選的69條彊震記錄,利用概率統計方法定量地分析P-Δ效應、屈服後剛度比、規一化屈服彊度和自振週期等因素對震後殘餘位移的概率統計特徵的影響,進而對殘餘位移與峰值位移之間的相關性進行討論,併建立殘餘位移與峰值位移之間的經驗預測方程。分析結果錶明:P-Δ效應、屈服後剛度比和規一化屈服彊度對殘餘位移的均值影響較大,而對殘餘位移的變異性影響相對較小;橋樑結構的震後殘餘位移可以描述為對數正態分佈或威佈爾分佈隨機變量;殘餘位移與峰值位移之間具有較彊的相關性,且二者比值的均值(變異繫數)隨著自振週期和穩定繫數的增大而增大(減小)。
잔여위이시평개교량결구진후가수복성화가용성적중요지표,이P-Δ효응대교량결구적잔여위이영향현저。종합고필P-Δ효응화지진동수궤특성적영향,통과대량적비탄성동력시정분석,정량지분석교량결구진후잔여위이적개솔통계특정화경험예측방정。수선근거동력평형원리,건립고필P-Δ효응적교량결구비탄성지진동력향응분석적운동공제미분방정,연후결합소사선적69조강진기록,이용개솔통계방법정량지분석P-Δ효응、굴복후강도비、규일화굴복강도화자진주기등인소대진후잔여위이적개솔통계특정적영향,진이대잔여위이여봉치위이지간적상관성진행토론,병건립잔여위이여봉치위이지간적경험예측방정。분석결과표명:P-Δ효응、굴복후강도비화규일화굴복강도대잔여위이적균치영향교대,이대잔여위이적변이성영향상대교소;교량결구적진후잔여위이가이묘술위대수정태분포혹위포이분포수궤변량;잔여위이여봉치위이지간구유교강적상관성,차이자비치적균치(변이계수)수착자진주기화은정계수적증대이증대(감소)。
Residual displacement is one of the most important parameters to assess the repairability and usability of bridge structures after an earthquake,while the P-Δeffect has significant influences on the residual displacement of bridge structures.Probabilstic characteristics and empirical prediction equations of residual displacements for bridge structures were quantitatively investigated based on the large number of nonlinear time history analyses by taking the P-Δeffect and randomness of strong ground motion into account.The governing differential equation of motion for bridge structures including the P-Δeffect was developed based on the dynamic balance theory.The influences of the P-Δeffect,post-yield stiffness ratio, normalized yield strength and natural period of vibration on statistical characteristics of residual displacement were quantitatively investigated based on the inelastic dynamic responses of bridge structures under the excitation of 69 selected records of strong ground motions.The correlation between the peak and residual displacements was discussed and the prediction equation for the residual-to-peak displacement ratio was also proposed.The results show that the P-Δeffect,the post-yield stiffness ratio and the normalized yield strength have significant impact on the mean of residual displacements;the residual displacement can be described as a lognormal or Weibull distribution variable;the correlation between the residual and peak displacements is remarkable and the mean (dispersion)of the residual-to-peak displacement ratios increases (decreases)with the increase of the natural period of vibration and the stability factor.