Simulation of dynamic behaviour of RC bridge with steel-laminated elastomeric bearings under high-energy mining tremors

In the paper a detailed analysis of dynamic responses of a reinforced concrete bridge with steel-laminated elastomeric bearings to high-energy mining tremors registered in two main regions of mining activity in Poland (i.e. Upper Silesian Coal Basin and Legnica-Glogow Copper District) was presented. The representative time histories of accelerations from both regions were used as ground motion data in calculations of the dynamic response of the structure. The two-coefficient Mooney-Rivlin model was used as a constitutive model for hyperelastic non-linear elastomeric material. It was proved that the dynamic response of the bridge was strongly dependent not only on the level of vibration amplitudes but on the dominant frequency range of the mining shock typical for the mining region as well. Also the height of elastomeric bearings occurred to have considerable influence on the total dynamic response of the bridge. Two heights of bearings were analyzed: 42 mm and 85 mm. The increase of the height of bearings caused the decrease up to 25 % in the maximal principal stresses obtained in the dynamic analysis. The behaviour of elastomeric material in case of bearings 42 mm high occurred to be strongly non-linear, whereas in case of bearings 85 mm high behaviour of elastomeric material remained almost linear.