基于性能的多层框架结构楼板开洞超限问题研究

发布时间：2018-06-04 01:43

本文选题：基于性能 + 框架结构　；参考：《石河子大学》2017年硕士论文

【摘要】：《高层建筑混凝土结构技术规程》(JGJ3-2010)第3.4.6条对楼板开洞作了如下规定:当楼板平面比较狭长、有较大的凹入和开洞时,应在设计中考虑其对结构产生的不利影响。有效楼板宽度不宜小于该层楼面宽度的50%;楼板开洞总面积不宜超过楼面面积的30%;在扣除凹入或开洞后,楼板在任一方向的最小净宽度不宜小于5m,且开洞后每一边的楼板净宽度不应小于2m。而在实际工程中,超出规范规定的楼板开洞问题比比皆是,其中楼板开洞面积、尺寸等往往超越规范对楼板开洞的规定。并且随着人们生活水平的提高,对建筑物的体型和功能要求越来越高,楼板开洞超限的现象也就越来越多。如果楼板开洞超限,可能会对结构产生不利的影响,削弱结构的抗震性能。国内外学者对于楼板开洞超限的框架结构的研究还不是很多,并且主要是对楼板进行的弹性计算分析。本论文针对楼板开洞超限问题进行研究,采用基于性能要求的抗震设计方法,对楼板带有各种形式开洞的结构进行模拟分析。运用PKPM软件中的PMCAD、SATWE进行建模和小震弹性计算分析、PMSAP进行楼板应力分析、EPDA对结构进行弹塑性计算分析。对计算结果进行分析,找出结构的薄弱部位,有针对性的采取抗震加强措施,为楼板开洞超限的建筑工程设计时提供参考。以下为主要的研究工作及结论:(1)考虑楼板的不同开洞面积,建立五个分析模型。在其他条件全部相同的情况下,通过控制结构首层的开洞尺寸,采用逐步增大首层开洞面积的方法,研究开洞率对结构抗震性能的影响。研究表明:楼板开洞面积越大,对结构越不利。当开洞面积大于30%时,会削弱结构的整体刚度,开洞附近楼板出现应力集中以及梁柱上出现塑性铰等现象。在采取加强措施之后,结构能达到预期的性能目标。(2)楼板在开洞面积和其他条件都相同时,分别在楼板中间、边缘和角部各开一个洞建立分析模型,研究开洞位置对结构抗震性能的影响。研究表明:在楼板的角部开洞对结构刚度的削弱较大,梁柱上出现塑性铰较多。在采取加强措施之后,结构能达到预期的性能目标。当在楼板的中间开洞时,楼板上出现明显的应力集中现象。(3)楼板在开洞面积和其他条件都相同时,分别在楼板中间、对边和对角各开两个洞口和开成不规则的L型洞口建立分析模型,研究开洞形式对结构抗震性能的影响。研究表明:开成不规则的L型洞时,对结构刚度的削弱较大。在楼板对角开两个洞时,结构受到的扭转效应最大。当在楼板中间开两个洞口时,楼板上出现明显的应力集中现象。(4)楼板在开洞面积相同时,分别在结构的首层开洞、中间层开洞、顶层开洞和全层都开洞建立分析模型,研究开洞楼层对结构抗震性能的影响。研究表明:在每层的楼板上都开洞时,对结构短边方向的抗侧刚度削弱较大,中震作用下楼板的整体应力水平较高。(5)考虑楼板之间的连接板尺寸建立分析模型,分别设定两个洞口之间不同的距离,从而使两个洞口之间的连接板形成不同的尺寸,研究连接板尺寸对结构抗震性能的影响。研究表明:不同的连接板尺寸,对结构的整体刚度影响较小,而连接板尺寸超限时,楼板上会出现应力集中的现象。
[Abstract]:"Technical specification for concrete structure of high building > (JGJ3-2010) section 3.4.6 provides the following provisions for the opening of the floor slab: when the floor plane is relatively narrow and has a larger concave and open hole, the adverse effects on the structure should be considered in the design. The width of the effective floor should not be less than 50% of the floor width of the floor; the total area of the floor slab should not exceed the total floor area. 30% of floor area; the minimum net width of floor slab in any direction should not be less than 5m after deducting concave or open holes, and the net width of floor slab on each side should not be less than 2M. after opening. In actual engineering, the opening problems of floor slab beyond the specification are abound, in which the floor area, size, etc. often exceed the standard opening to the floor. And with the improvement of people's living standards, the requirements for the shape and function of buildings are getting higher and higher, and the opening of the floor is more and more limited. If the opening of the floor is Overlimited, it may have a negative impact on the structure and weaken the seismic performance of the structure. It is not much, and it is mainly the elastic calculation and analysis of floor slab. In this paper, the problem of opening and exceeding the limit of the floor is studied. Using the seismic design method based on the performance requirements, the structure of the floor with various forms of opening is simulated and analyzed. The modeling and the elastic calculation and analysis of the small earthquake are carried out by using the PMCAD, SATWE in the PKPM software. PMSAP carries out the analysis of the floor stress and the elastic and plastic analysis of the structure by EPDA. The results are analyzed, the weak parts of the structure are found, and the anti-seismic measures are taken to provide reference for the design of the building engineering. The following are the main research work and conclusions: (1) considering the different opening surfaces of the floor slab. Five analysis models are set up. Under all the other conditions, the effect of opening rate on the seismic performance of the structure is studied by controlling the opening size of the first layer of the structure and the opening area of the first layer gradually. The study shows that the larger the opening area of the floor is, the more unfavorable the structure is. When the opening area is greater than 30%, the knot will weaken the knot. The whole stiffness of the structure, the stress concentration in the floor near the opening and the plastic hinge on the beam and column. After the strengthening measures, the structure can reach the expected performance target. (2) the floor is at the same time in the opening area and other conditions, and the analysis model is set up in the middle of the floor, the edge and the corner, and the opening position is studied. The study shows that the structural stiffness is weakened greatly in the corner of the floor, and there are more plastic hinges on the beam and column. After the reinforcement measures are taken, the structure can reach the desired performance target. When the floor is opened in the middle of the floor, the obvious stress concentration is found on the floor. (3) the floor area is in the opening area and in the opening area. The other conditions are at the same time, the analysis model is set up in the middle of the floor, two openings on the side and the diagonal and the irregular L cavities. The influence of the opening form on the seismic performance of the structure is studied. The study shows that when the irregular L hole is opened, the stiffness of the structure is weakened greatly. When the floor is open to the corner of the two holes, the structure is subjected to the structure. When two holes are opened in the middle of the floor, there is an obvious stress concentration on the floor. (4) at the same time, the floor is opened in the first layer of the structure, the opening of the middle layer, the opening of the top layer and the whole layer are opened to establish the analysis model to study the effect of the opening floor on the seismic performance of the structure. When the floor of the floor is open, the lateral stiffness of the short side of the structure is weakened greatly, and the overall stress level of the floor is higher under the action of medium earthquake. (5) the analysis model is established to establish the analysis model of the connecting plate size between the floors, and the different distances between the two holes are set respectively, so that the different sizes of the connecting plates between the two holes are formed. The influence of the size of the connecting plate on the seismic performance of the structure shows that the different size of the connecting plate has little effect on the overall stiffness of the structure, while the stress concentration will appear on the floor when the size of the connecting plate is beyond the limit.
【学位授予单位】：石河子大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TU323.5

【参考文献】