井塔结构中转换梁的受力性能分析

发布时间：2019-04-16 19:49

【摘要】：本文以门克庆矿井主立井井塔工程为依托,将该井塔底部抽柱方案中的转换大梁设计为型钢混凝土转换梁,并利用有限元软件SAP2000对型钢混凝土转换梁与转换梁所支撑的上部框架构件在水平和竖向荷载下的内力分布变化情况进行静力弹性分析,并与落地框架下相应部位的构件内力相比较,分析并总结转换梁内力及上部框架内力的变化规律,从而探索减小转换梁内力的上部框架构件的刚度调整方案;并利用有限元软件ABAQUS对大跨度型钢混凝土转换梁受力性能进行了竖向和水平荷载下拟静力弹塑性分析研究,研究了型钢腹板厚度、配筋率、型钢保护层厚度等因素对转换梁受力性能的影响,得到以下结论,可供井塔结构设计时参考。⑴与落地框架相比,转换梁上部框架构件的内力有向边柱方向集中的趋势,尤其是与转换层直接相连的一层,应该是设计中引起重视的部位。在水平荷载作用下,随着上部框架侧移量的增大,转换梁上部框架构件的内力也有较大增幅。⑵对大跨度转换梁结构体系来说,增大转换梁上部框架边梁和边柱刚度能有效降低转换梁的内力,增大上部框架中柱并不能明显地降低转换梁的内力。⑶在竖向荷载作用下,托柱转换梁顶部压应力向梁端方向逐渐减小,仅在端部小范围内混凝土受拉;转换梁底部的拉应力向梁端方向逐渐减小,仅在端部小范围内混凝土受压。型钢混凝土转换梁在靠近梁端部位主要由纵向钢筋和箍筋来承担内力,在跨中方向主要由型钢来承担内力。在满足转换梁刚度和承载力的情况下,适当的增大型钢保护层厚度可以改善转换梁的延性及受力性能,型钢翼缘宽度对转换梁的延性影响较小。⑷在需要降低转换梁挠度和增强转换梁承载力时,应优先考虑增大型钢腹板厚度的方式来改善转换梁的受力性能,但提高型钢腹板厚度转换梁的延性影响较大。⑸提高转换梁的配筋率,会降低转换梁的延性,对结构抗震不利,易造成型钢梁柱节点处的施工困难;适当的增大转换梁配筋率,可以提高转换梁的承载力,有利于型钢和纵筋的共同工作性能。
[Abstract]:In this paper, on the basis of the main shaft tower project in Menckeqing mine, the conversion beam in the pumping scheme of the bottom of the tower is designed as the section steel concrete transfer beam. By using the finite element software SAP2000, the static elastic analysis of the internal force distribution of the steel reinforced concrete transfer beam and the upper frame member supported by the transfer beam under horizontal and vertical loads is carried out. Compared with the internal forces of the corresponding parts of the frame on the ground, the change rules of the internal forces of the converted beam and the upper frame are analyzed and summarized, so as to explore the stiffness adjustment scheme of the upper frame members which can reduce the internal forces of the converted beams. The finite element software ABAQUS is used to analyze the mechanical behavior of long-span steel reinforced concrete transfer beams under vertical and horizontal loads, and the thickness and reinforcement ratio of steel web plates are studied. The influence of the thickness of the protective layer of section steel on the mechanical performance of the transfer beam, the following conclusions can be used for reference in the design of the well tower structure. 1. Compared with the landing frame, the internal force of the upper frame member of the transfer beam tends to concentrate in the direction of the side column. In particular, a layer that is directly connected to the conversion layer should be an important part of the design. Under the action of horizontal load, with the increase of the lateral displacement of the upper frame, the internal force of the upper frame member of the transfer beam also has a large increase. 2 for the long-span transfer beam structure system, Increasing the stiffness of the side beam and column in the upper frame of the transfer beam can effectively reduce the internal force of the transfer beam, and the increase of the column in the upper frame can not significantly reduce the internal force of the transfer beam. 3 under the vertical load, the internal force of the transfer beam can not be reduced significantly. The compressive stress at the top of the post transfer beam decreases gradually towards the end of the beam, and the concrete is pulled only in a small range at the end of the beam. The tensile stress at the bottom of the transfer beam decreases gradually towards the end of the beam, and the concrete is compressed only in a small range at the end. The internal forces of the steel-reinforced concrete transfer beam are mainly borne by longitudinal reinforcement and stirrups near the end of the beam, and mainly by the section steel in the middle direction of the span. Under the condition that the stiffness and bearing capacity of the transfer beam are satisfied, the ductility and mechanical performance of the transfer beam can be improved by properly increasing the thickness of the steel cover. The width of the flange has little effect on the ductility of the transfer beam. 4 when the deflection of the transfer beam is reduced and the bearing capacity of the transfer beam is strengthened, the way of increasing the thickness of the steel web should be given priority to improve the mechanical performance of the transfer beam. 5. Increasing the reinforcement ratio of the transfer beam will reduce the ductility of the transfer beam, which is unfavorable to the seismic resistance of the structure, and it is easy to cause the construction difficulty at the Liang Zhu joint of the section steel. (2) improving the ductility of the transfer beam with the thickness of the web plate has a great influence on the ductility of the beam. If the reinforcement ratio of the transfer beam is increased properly, the bearing capacity of the transfer beam can be improved, which is beneficial to the joint working performance of the section steel and the longitudinal reinforcement.
【学位授予单位】：西安科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TU398.9

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