Experimental Study On Mechanical Characteristics And Transverse Load Distribution Of Large-angle Hinged Skew Slab Bridge

The positions of Medium and small bridges, culverts, tunnels or general structures should obey the road line shapes. In recent years, many medium or small skew bridges had been built, and large-angle hinged skew slab bridges increase monotonically at the same time. In order to making bridge designing be more reasonable, transverse load distribution and mechanical characteristics of large-angle hinged skew slab bridges should be studied in deeply.Transverse load distribution of large-angle hinged skew slab bridges will be studied in this paper. And mechanical characteristics which are unlike to the ones of right bridge are expected to be discovered.According to the previous research results of hinged skew slab bridges, the method of calculating influence line of transverse load distribution by using empirical formula is put forward in this paper.Firstly, one bridge with 8 slabs,45°skew angle is studied with using FEA software-MIDAS/Civil. In order to establish a reliable numerical model, shear-flexible grillage method is adopted, section types and material parameters of virtual crossbeam are adjusted, and boundary conditions such as hinge joint, support condition are determined.Organic glass model is made for verifying the reasonableness of numerical model. In order to make the test model be as close as possible to the prototype model, using the form of incomplete hinged joints to replace real hinge joints, rubber blocks be bonded on one end as fixed bearings, the other side not bonded as sliding bearings. Then, similarity criterion is calculated with using dimensional analysis method. And the results of organic glass model has good coupling to numerical model, so numerical model can be considered as correct. This numerical modeling method can be used to analysis other hinged skew slab bridges with different angles.In order to verify if width-span ratio, torsional rigidity, flexural rigidity will impact the coupling effect, right bridge's numerical model is established to be analysised. By changing slab's width-span ratio, torsional rigidity and flexural rigidity, half-wave sinusoidal load loading on slabs, influence line of transverse load distribution is calculated. The results are compared with the theoretical calculation results. And the results of the two methods have small relative error, so numerical model can be considered as correct.There are 56 numerical models of hinged skew slab bridges with different slabs, different skew angles are established by shear-flexible grillage method, which reveal the relationships of internal force and skew angles. Empirical formulas of influence line of transverse load distribution with the skew angle coincide with theoretical calculation, so the empirical formulas are reliable.The maximum bending moments of large-angle hinged skew slab bridges decrease as the increasing of skew angle. It can be calculated with using empirical formulas on the base of having calculating right bridges'maximum bending moments.The characteristics of large-angle hinged skew slab bridges'bending moments which different with the right bridges are shown in this paper. It can give reference for designing other large-angle hinged skew slab bridges.