【作者】 张玲；

【导师】 张南；

【作者基本信息】 南京工业大学 ， 桥梁与隧道工程， 2015， 硕士

【摘要】 钢骨混凝土结构是在钢筋混凝土里面插入型钢或者型钢骨架而形成的组合结构体系。与普通钢筋混凝土结构相比,钢骨结构具有整体性好,强度高,承载力强、抗动力性能好、施工快捷等优点。基于这些优点,不管在建筑结构还是桥梁工程中都会流行起来。随着钢骨结构的大面积应用,其性能也得到了学者和研究设计人员的广泛关注和研究。随着我国高速公路工程的迅猛发展,桥梁建设规模也不断增长。不管是跨江河桥梁还是跨线桥梁,都是公路交通运输系统中的瓶颈。近年来全国乃至全世界,经常发生桥梁被撞事故,造成桥梁损坏、垮塌等严重后果。目前有关桥墩的动强度设计这一方面的研究较少。本文共设计2根钢筋混凝土桥墩和5根钢骨混凝土桥墩(包括3根角钢混凝土桥墩和2根槽钢混凝土桥墩),分别进行静力集中力加载试验和侧向撞击试验,以研究钢骨混凝土桥墩在静力集中荷载和撞击荷载作用下的性能,主要研究内容和成果如下：1、通过对一组钢筋混凝土梁和缓冲装置分别进行静力和撞击试验,并在部分梁上加缓冲装置,分析梁和缓冲装置的性能,对静动响应关系进行试验基础研究。得到了梁的钢筋应变曲线、箍筋应变曲线、混凝土应变曲线、位移曲线和缓冲装置压缩曲线。2、分析试验梁所得曲线,对静动荷载下的响应进行对比,可见动态荷载作用下梁各部分响应要高于静态荷载下的,对构件进行动强度设计时应考虑动响应；将缓冲装置的静动压缩曲线进行对比,可见缓冲装置在动荷载作用下吸收的能量比静荷载作用下的多；将缓冲装置吸收的能量扣除后构件的应变与同等撞击能量作用下的构件对比,可见缓冲装置对撞击荷载的特性和构件的动力响应均有较显著的影响。由于静动关系具有相似性,为后续研究桥墩的静动响应关系及缓冲装置对动力响应的影响提供参考,作为桥墩分析的基础。3、通过对钢骨混凝土桥墩进行静动对比试验。对静态荷载作用下的荷载位移曲线进行分析,可见钢骨改善了桥墩的性能,提高了桥墩的极限承载能力,很大程度上抑制裂缝的出现和发展。对撞击荷载作用下的钢筋应变进行分析,缓冲装置显著降低了钢筋应变峰值；将动应变的峰值与静力作用下的应变进行比较,研究应变放大系数的一般规律。4、分别研究静力作用下的位移和动力作用下的位移响应,运用微分方程,将撞击力分别等效为阶跃力和三角波荷载,得到位移响应表达式；再将静动响应进行对比,得到动力位移放大系数的计算公式,分析了影响位移响应和位移放大系数的影响因素,将理论所得位移放大系数与试验所得结果相比,符合较好,为研究桥墩动力强度设计提供一定的研究基础更多还原

【Abstract】 Steel reinforced concrete structure is a combined structure system in which we put section steel or skeletons of it inside the reinforced concrete. Comparing with common reinforced concrete structures, there is many advantages such as steel saving, better integrity, higher bearing capacity, better anti-seismic performance, more convenient construction and so on, Which make a brightening prospect of the application in building engineering and bridge engineering. And with the wider and wider application of section steel, it have led scholars and designers to widespread concerns and researches on its performance.With rapid development of Highway engineering in our country, the scale of bridge construction is increasing. No matter river bridges, sea bridges or cross line bridges, are all the bottlenecks of highway transportation system. But in recent years,accidents of motor vehicle-pier or vessel-pier collisions often occurred, causing serious damages or even collapses to the bridges, meanwhile, the researches on the design of dynamic strength of bridge piers are still rudimentary. In this work,2 reinforced concrete piers and 5 steel reinforced concrete piers (including 3 angle section steel concrete piers and 2 channel section concrete piers) are designed to study the performance of reinforced concrete piers under static concentrated load and impact loads, by the tests in which the piers were loaded under lateral concentrated loads and horizontal impact loads respectively. And the main contents and results of the research are as follows:1、The performances of the beams and the buffering devices are revealed by static and impact tests, in which the beams, buffers and beams with buffers on them were loaded under static loads and impact loads respectively. And relationships between the static and dynamic responses are also revealed based on the tests. Thus the reinforcement strain curves, stirrup strain curves, concrete strain curves and displacement curves of the beams and time-history curves of the compression of buffers are all concluded due to the results of tests.2、By analysis of the curves of beams in the tests concluded, responses of the beams under dynamic loads are obviously higher than that under static loads, which means the dynamic loads are non negligible factors when designing the strength of construction members. The energy absorption of buffers under dynamic loads are higher than that under static loads, which is told by the curves of the buffers under static-dynamic loads. After the energy absorbed by buffers are deducted, we compared the strains of the components with those under equivalent impact energy, and it is seen that the buffers are obviously influential on the properties of impact loads and dynamic responses of the components, which provide basic researches for follow-up studies on the certain relationships of static-dynamic response of piers and the influences of buffer devices on components under dynamic loads.3、By the contrast test of steel reinforced concrete bridge piers under static and dynamic loads, combined with analysis of the load-displacement curves under static loads, the performances of the piers are improved by section steels, also, the ultimate loads of the piers are improved, and the development of cracks are effectively inhibited; By the analysis of the load-displacement curves on reinforced strains under impact loads, buffers device significantly reduced the peak strain of reinforcements; Comparing the peak value strains under dynamic loads and the static stains in the experiment, the ratio obtained was rather discrete, which means the study of strain amplification factors is not a focus here.4、By using differential equations, combing the status of the displacements under static loads and dynamic loads respectively, the displacement response expression is acquired after taking the impact forces equivalent to step forces and triangle wave loads; And by comparing the static and dynamic responses, the expression of the calculation of the amplification factors of displacement were concluded, and the influence factors of displacements and amplification coefficients of displacements are analyzed, and the amplification coefficients of displacements on theory agree well with the actual test results, which provide basic researches for further studies on the design of dynamic strengths of bridge piers.更多还原