|
As early as in the 1950s and 1960s, China built a number of T-beam bridge, due to the simple structure, easy installation, this bridge type to improve China's road transport plays an important role. However, with the development of transportation, traffic volume is growing, increasing vehicle load, as well as T-beams were also exposed some problems with increasing operator of years, due to flange thickness is much smaller than the beam height, the beam lateral connections hinged consider, due to the structure of the wing meets the height that much difference with the high beam, the hinged role is difficult to achieve, and did not set enough lateral ties, resulting in damage flange connections; press then just consider the transverse beam connection, if the beams set the number is not enough, do not form a horizontal rigid connection, the actual stress state inconsistent with the theory, the formation of the single beam excessive force damage, also very weak when the beam itself resistance easy to be damaged due to withstand large lateral bending force, the bridge carrying capacity is reduced year by year. Especially before the construction of the bridge design standards, the bearing capacity can not meet the needs of the transport development; reinforced concrete T-beam bridge with the growth of the useful life, in addition to the conservation timely naturally occur on the surface of concrete carbonation cracks increase, surface damage, water intrusion, a series of questions such as steel corrosion, will eventually lead to decline in the bearing capacity of the bridge, the disease, become sick Bridge, a dangerous bridge, or more seriously, cause bridge collapse, the national economy to some extent, restricted development. Author access to a large number of documents, a more comprehensive understanding of the research areas at home and abroad its progress. On this basis, Xiaogan City Bayi Bridge engineering background, analysis and reinforcement research on the the Bayi Bridge existence of disease. Mainly carry out the following tasks: (1) checking the main beam design load borne by the traditional method, the analysis of the main reason of the bridge cracks and proposed three enhanced assembly T girder bridge the horizontal linkages reinforcement program; program: replacement diaphragms program, the serious damage to the diaphragms of welding quality reinforced steel plate repair welding; program: the composite beam program, chisel in addition to the existing bridge deck pavement, re-arrangement of the steel mesh, cast-in-place 15cm thick concrete, made the whole bridge deck implanted blocking a certain pitch in the top of the T-Beam steel, welded together with the the bridge panel of reinforced joint force coordination deformation, making the bridge deck and the main beam. Option Three: the T switch box program, paste in the bottom of the T-beam layer of 6mm thick steel plate so that the bottom of the T beam web closed form steel - concrete composite box section. (2) for the three scenarios respectively modeling using finite element software, mechanical analysis of the the Bridge main structure parts; analysis shows that meet the requirements of simply supported reinforced concrete T-beam bridge carrying capacity of the main beam, deck longitudinal cracks generation was mainly due to the bridge after the destruction of the diaphragm in the overloaded vehicles under the T beam flange plate transverse tensile stress in Japan T beam deformation in the car under uncoordinated. (3) The results of three contrast, and as a basis for reinforcing bridge design; The results show that, bar technique, the replacement of the bridge deck pavement reinforcement reinforcement of the diaphragm and the diaphragm simple reinforcement program compared to the former not only on the mechanical index better, more convenient construction, but also more economical and reasonable. Thesis work on the Old Bridge Reconstruction Design.
|