高温下预应力混凝土叠合板抗火性能及其承载力研究

发布时间：2018-06-14 10:22

本文选题：预应力混凝土叠合板 + 抗火性能　；参考：《西安建筑科技大学》2017年硕士论文

【摘要】：建筑火灾是发生次数最多、损失最为严重的主要灾害之一,随着预应力混凝土叠合板的广泛应用,人们逐渐重视对其抗火性能研究。预应力混凝土叠合板是一种实用的装配整体式楼板,具有预制装配式楼板和现浇整体式楼板两方面优点,即整体刚度好、抗震性能高、施工简便及工期较短等优点。预应力混凝土叠合板已经应用到了很多项目上,创造了良好的社会效益。因此,研究预应力混凝土叠合板的抗火性能是至关重要的。本文的主要工作如下:(1)运用ANSYS软件对两种预应力混凝土叠合板进行了瞬态热分析,得到了不同升温时间下叠合板板截面的温度场;对两种叠合板进行热-结构耦合分析,得到了升温180min时两种叠合板的应力云图、应变云图及跨中竖向位移;结果表明,在叠合板的叠合层底部配受拉钢筋其抗火性能要优于标准的叠合板。(2)基于构件截面等效强度的原则,把高温下的钢筋混凝土受弯构件截面等效成常温下的钢筋混凝土受弯构件截面,提出了高温下受弯构件截面承载力的二台阶模型计算方法;运用ANSYS软件对单面升温的钢筋混凝土简支梁的正截面受弯承载力进行分析;结果表明,公式计算值与ANSYS软件分析结果符合较好。(3)在二台阶模型的计算方法下,考虑到板的受拉薄膜效应,根据双向板的板块平衡法和能量法,分别计算出高温下预应力混凝土叠合板的极限荷载;结果表明,高温条件下能量法的计算结果比板块平衡法的计算结果保守,具有一定的安全冗余度。(4)运用能量法对预应力混凝土叠合板进行抗火设计。对不同耐火等级下民用建筑应使用的预应力混凝土叠合板的种类给出了建议;提出了确定不同板型叠合板在不同温度下极限承载力表格的方法。
[Abstract]:Building fire is one of the most frequent and serious disasters. With the wide application of prestressed concrete composite slab, people pay more and more attention to the study of its fire resistance. Prestressed concrete composite slab is a kind of practical assembly integral floor slab, which has the advantages of prefabricated assembly floor and cast-in-place integral floor, such as good overall stiffness, high seismic performance, simple construction and short construction period, etc. Prestressed concrete composite slab has been applied to many projects and has created good social benefits. Therefore, it is very important to study the fire resistance of prestressed concrete composite slab. The main work of this paper is as follows: (1) the transient thermal analysis of two kinds of prestressed concrete composite slab is carried out by using ANSYS software, and the temperature field of the cross-section of the composite slab is obtained under different heating time, and the thermal-structural coupling analysis is carried out for the two kinds of composite slab. The stress cloud, strain cloud and vertical displacement of the two laminated plates are obtained when the temperature is raised by 180min, and the results show that, The fire resistance of tensile reinforcement at the bottom of the laminated plate is superior to that of the standard laminated plate. (2) based on the principle of the equivalent strength of the section of the member, The section of reinforced concrete flexural member at high temperature is equivalent to that of reinforced concrete flexural member at normal temperature, and a two-step model method for calculating the bearing capacity of flexural member section at high temperature is proposed. The flexural bearing capacity of reinforced concrete simply supported beams with single side heating is analyzed by ANSYS software, and the results show that the calculated values of the formulas are in good agreement with the results of ANSYS software. According to the plate equilibrium method and energy method of bidirectional slab, the ultimate loads of prestressed concrete composite slab at high temperature are calculated according to the tensile film effect of the slab, and the results show that, The results of energy method under high temperature are conservative than those of plate equilibrium method, and have a certain degree of safety redundancy. The energy method is used to design the fire resistance of prestressed concrete composite slab. The types of prestressed concrete laminated slabs for civil buildings with different fire resistance grades are suggested, and the method for determining the ultimate bearing capacity of different plate type composite plates at different temperatures is presented.
【学位授予单位】：西安建筑科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TU378;TU352.5

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