横梁对装配式钢筋混凝土简支T梁桥受力性能的影响

发布时间：2018-03-13 04:15

本文选题：装配式钢筋混凝土T梁桥　切入点：横梁　出处：《清华大学》2015年硕士论文　论文类型：学位论文

【摘要】：对于装配式钢筋混凝土简支T梁桥,横梁设置状况与损伤状况对结构在设计阶段和运营阶段的受力与可靠度产生较大的影响。本论文基于荷载横向分布的概念,对不同横梁设置与损伤工况下的荷载横向分布特性与可靠度展开了系列研究,取得的主要研究成果如下:(1)在设计阶段,从主梁跨中截面受弯角度看,当按照《通用规范》布置荷载时,设置中横梁对结构受力起不利作用。设置中横梁对降低了内主梁的设计弯矩,但增大了桥梁最外侧主梁设计弯矩,并且使得桥梁最大设计弯矩增大。由于《通用规范》的布载方式是结构最不利布载方式,因此,可认为设置中横梁增大了结构在最不利工况下的跨中截面弯矩,对于主梁受弯起不利作用。(2)从翼缘受剪与主梁受扭角度,对“单板(梁)受力”现象给出解释。工程界认为“单板(梁)受力”现象是由于横梁损伤后,单个主梁所受弯矩与剪力增大造成的。本论文通过研究,认为设置中横梁并不一定能够降低主梁所受弯矩与剪力,但有利于降低翼缘板剪力和主梁扭矩,保护翼缘板和主梁腹板等薄弱部位,防止这些部位产生裂缝,避免“单板(梁)受力”现象。(3)编制了装配式钢筋混凝土T梁桥常用截面形式荷载横向分布系数计算表。为了便于工程设计,本文以刚接板(梁)法为基础,按照《通用规范》布置车辆荷载,计算出荷载横向分布系数设计值,并将其编制成表,便于设计时查询。(4)研究了实际车流作用下,横梁设置与横梁损伤对主梁可靠度的影响。实际车流与《通用规范》规定的荷载存在差别,本研究利用某高速公路62天连续测量的实际车流,计算出主梁的可靠度。研究表明,设置中横梁能够提高主梁在最不利布载工况下的可靠度,因此宜设置跨中横梁。当跨中横梁损伤后,在最不利布载工况下,主梁可靠度下降,因此,当横梁损伤后,应当及时进行修复。
[Abstract]:For the prefabricated reinforced concrete simply supported T-beam bridge, the transverse beam configuration and damage condition have a great influence on the stress and reliability of the structure in the design and operation stages. This paper is based on the concept of transverse load distribution. In this paper, a series of studies are carried out on the transverse load distribution and reliability of beams under different load setting and damage conditions. The main research results obtained are as follows: 1) in the design stage, from the angle of bending of the mid-span section of the main beam, When the load is arranged according to the general code, the mid-beam is unfavorable to the structure. The mid-beam reduces the design moment of the inner main beam, but increases the design moment of the outermost main beam of the bridge. And the maximum design bending moment of the bridge is increased. Because the load distribution mode of the general specification is the most unfavorable way of the structure load distribution, it can be considered that the mid-span bending moment of the structure under the most unfavorable working conditions is increased by the setting of the crossbeam. (2) from the angle of flange shear and main beam torsion, the phenomenon of "single plate (beam) force" is explained. The engineering field thinks that the phenomenon of "single plate (beam) force" is due to the damage of the beam. In this paper, it is concluded that the moment and shear force of the main beam may not be reduced by setting the beam, but the shear force of the flange plate and the torque of the main beam can be reduced by the increase of the bending moment and shear force of a single main beam. To protect weak areas such as flange plates and main beam webs, and to prevent cracks in these areas, To avoid the phenomenon of "single slab (beam) force", a table for calculating the transverse load distribution coefficient of common section form of prefabricated reinforced concrete T-beam bridge is developed. In order to facilitate the engineering design, this paper is based on the rigid plate (beam) method. According to the general specification for the layout of vehicle loads, the design values of load transverse distribution coefficients are calculated and compiled into a table, which is convenient to inquire about when designing. 4) under the action of actual traffic flow, The influence of beam setting and beam damage on the reliability of the main beam. The actual traffic flow is different from the load specified in the General Code. In this study, the reliability of the main beam is calculated by using the actual traffic flow measured continuously for 62 days on a certain expressway. The reliability of the main beam under the most unfavorable load distribution condition can be improved by setting the middle beam, so it is advisable to set the middle span beam. When the middle span beam is damaged, the reliability of the main beam decreases under the most unfavorable load distribution condition, therefore, when the beam is damaged, the reliability of the main beam decreases under the most unfavorable load distribution condition, so when the beam is damaged, Repairs should be made in time.
【学位授予单位】：清华大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U441

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