Seismic Response Analysis Of Large - Scale Aqueduct Structure Considering Three - Dimensional Contact Friction Effect

The safety of large-scale aqueduct on seismic is beneficial to the people’s livelihood, its structural form is not conducive to seismic and there is no standard to follow in the design. The most common form of damage to large-scale aqueduct is due to pounding of adjacent segments at the expansion joints. And because of creep, uneven settlement, temperature change, the expansion joint is essential. But at present there is less the study of aqueduct pounding at the expansion joints, and the pounding effect was usually simulated with a contact element, this method is based on the point to point pounding assumption and the pounding location is predefined. While the research on the 3D nonlinear contact friction pounding is not yet mentioned. So it is important to study the 3D contact friction response of the seismic induced damage of large-scale aqueduct.This paper concentrates on the pounding of large-scale aqueduct structure at the expansion joints, performs numerical simulations of pounding between aqueduct girders and between aqueduct girder and the corresponding abutment of a three-span simply-supported aqueduct to ground motions based on a detailed 3D finite element model by using the explicit finite element code ANSYS/LS-DYNA. The calculation results show that the detailed 3D finite element model by using the explicit finite element code ANSYS/LS-DYNA is able to simulate pounding of large aqueduct structure under the ID excitation and 3D excitation.This paper performs numerical simulations of pounding between aqueduct girders and between aqueduct girder and the corresponding abutment of a three-span simply-supported aqueduct under the longitudinal excitation based on a detailed 3D finite element model by using the explicit finite element code ANSYS/LS-DYNA. Based on the calculation results, this paper analyzes the response of aqueduct structure under seismic, including displacement, relative displacement, displacement of pier top, pounding force, pounding frequency, contact friction value, and so on, discusses the factors affecting the pounding of aqueduct structure under earthquake. and the difference between considering the effect of abutment and no abutment. The result of calculation shows that the result of not considering the effect of abutment is more discrete than considering the effect of abutment. Therefore, the seismic performance of aqueduct structure according to considering the effect of abutment design is higher.This paper analyzes the pounding response of aqueduct under multi-dimensional earthquake in three different conditions. First condition is longitudinal and transverse excitation, second is longitudinal and vertical excitation, last is longitudinal, transverse and vertical excitation. This paper analyzes the pounding forces and pounding stress, comparisons of the resultant pounding forces and pounding stress generated by different ground excitations. Aqueduct responses and damage to 1D and multi-dimensional ground excitations are very different. Traditional analysis of aqueduct pounding responses considering only 1D ground excitations and 1D aqueduct response may lead to incorrect predictions of pounding responses and underestimate pounding damage.