發(fā)布時間：2018-11-14 14:45

【摘要】：隨著我國近年來地面交通的迅猛發(fā)展,需要大量大跨徑的橋梁來通過寬廣的海峽、大江或峽谷,而三塔懸索橋基于其獨特的跨度優(yōu)勢及經(jīng)濟性,越來越受到工程師的青睞。而最近幾年頻發(fā)的強震所帶來巨大的生命財產(chǎn)損失,也為我們敲響了警鐘,對于大跨懸索橋的抗震分析應予以足夠的重視。本文以某三塔懸索橋為工程背景,運用有限元分析方法,對其在土-結構相互作用下的地震響應進行了分析。本文主要工作如下：(1)介紹了幾種常用的土-結構相互作用模型,并簡單介紹了建立NIST六彈簧模型以模擬土-結構相互作用的基本步驟；(2)采用六彈簧法建立了三跨懸索橋考慮土-結構相互作用的模型,并對考慮與不考慮土-結構相互作用的兩個模型進行了自振特性的比較分析。結果表明懸索橋在考慮了土-結構相互作用之后,會影響到橋梁整體的剛度,使其剛度降低；(3)對考慮與不考慮土-結構相互作用模型運用一致激勵法,計算了三塔懸索橋的地震響應,對結果進行了分析比較,討論了土-結構相互作用對三塔懸索橋地震響應的影響。結果表明,考慮土-結構相互作用后,對內(nèi)力的影響較大；(4)采用多點激勵法,對考慮土-結構相互作用的模型進行了行波效應下的地震響應時程計算,比較分析了不同視波速下行波效應的影響,并對照一致激勵的結果進行了分析。結果表明,行波效應對大跨懸索橋的影響隨波速的不同有較大的波動,實際工程中應根據(jù)場地地質條件選取合適的視波速。
[Abstract]:With the rapid development of ground transportation in China in recent years, a large number of long-span bridges are needed to pass through wide straits, rivers or canyons, while three-tower suspension bridges are more and more favored by engineers because of their unique advantages in span and economy. In recent years, the frequent strong earthquakes have brought huge loss of life and property, which has also sounded the alarm for us. The seismic analysis of long-span suspension bridges should be paid enough attention to. In this paper, the seismic response of a three-tower suspension bridge under soil-structure interaction is analyzed by using finite element method. The main work of this paper is as follows: (1) several commonly used soil-structure interaction models are introduced, and the basic steps of establishing NIST six-spring model to simulate soil-structure interaction are briefly introduced. (2) A three-span suspension bridge model considering soil-structure interaction is established by using the six-spring method, and the natural vibration characteristics of the two models with or without soil-structure interaction are compared and analyzed. The results show that the overall stiffness of the suspension bridge will be affected and the stiffness will be reduced after considering the soil-structure interaction. (3) the seismic response of the three-tower suspension bridge is calculated by using the consistent excitation method for considering and disregarding soil-structure interaction, and the results are analyzed and compared. The effect of soil-structure interaction on seismic response of three-tower suspension bridge is discussed. The results show that the influence of soil-structure interaction on internal force is great. (4) the seismic response time history of the model considering soil-structure interaction is calculated by using multi-point excitation method, and the effect of downlink wave effect at different apparent wave velocities is compared and analyzed. The results of consistent excitation are analyzed. The results show that the influence of traveling wave effect on long-span suspension bridge has great fluctuation with different wave velocities, and the appropriate apparent wave velocity should be selected according to the geological conditions of the site in practical engineering.
【學位授予單位】：西南交通大學
【學位級別】：碩士
【學位授予年份】：2015
【分類號】：U442.55;U448.25

【參考文獻】

相關期刊論文 前6條

1 吳懷忠;王汝恒;郭文;初文榮;;土與結構相互作用理論[J];四川建筑科學研究;2008年05期

2 林家浩;隨機地震響應的確定性算法[J];地震工程與工程振動;1985年01期

3 林家浩;非平穩(wěn)隨機地震響應的精確高效算法[J];地震工程與工程振動;1993年01期

4 林家浩，，李建俊，張文首;結構受多點非平穩(wěn)隨機地震激勵的響應[J];力學學報;1995年05期

5 楊孟剛;陳政清;胡建華;;自錨式懸索橋磁流變阻尼器減震控制研究[J];土木工程學報;2006年11期

6 焦常科;李愛群;操禮林;王浩;;三塔懸索橋行波效應研究[J];土木工程學報;2010年12期

本文編號：2331467