Numerical Analysis Of Coupled Action Between River Bridge-soft Soil Foundation System And Heavy Vehicle As Well As The Engineering Application

The settlement of river bridge-saturated soft soil foundation system subjected to theheavy vehicle is large. Based on this engineering phenomenon, a heavy vehicle-riverbridge-saturated soft soil foundation model is established to analyze it. The analysis ofdynamic interaction between a heavy vehicle and a bridge is studied by the application offinite element method(FEM) and Wilson θmethod. This model is applied to a projectcalled Qiaomuwanleanhe Bridge to analyze the dynamic response of the car-bridge systemas well as the ground settlement. The ground vibration caused by the bridge vibration isachieved by the application of analytic method. The numerical results is compared with thefindings of relative literatures. The main content contains:(1) Two different models are established to study the coupled action between theheavy vehicle and river bridge system. The bridge is modeled with Euler-Bernoulli bridgeand dispersed with beam element. The vibration equation of the car and the bridge isestablished respectively. The vibration equation of the car-bridge system is thenestablished by the application of finite element method(FEM) based on the coordinativerelation of the force and the displacement between the car and the bridge. A Wilson θmethod is applied as a numerical simulation in time domain of the car-bridge vibrationequation to analyze the dynamic response;(2) The computing result of coupled heavy vehicle-river bridge is compared with themonitoring data to prove the validation of the coupled heavy vehicle-river bridge vibrationmodel. The main factors influencing the coupled action of heavy vehicle-bridge vibrationincluding the weight and speed of the heavy vehicle and the bridge span and damping ratioof the river bridge are studied.(3) In the heavy vehicle-river bridge-saturated soft soil foundation system, the pier isidealized as a rigid body. The analytic solution u(t,x) of the vibration equation of acontinuous beam is achieved by the application of modal analysis method. Thedisplacement caused by the vibration of the continuous beam is passed from the rigid pierto the foundation-ground system. The ground settlement is achieve with the application ofempirical formulas;(4) The most important factors influencing the vibration of the saturated soft soilfoundation including the vehicle speed, the vehicle weight and distance of the watch pointare studied.This paper provides a new method to analyze the vibration of car-bridge system withfinite element method(FEM) and Wilson θmethod in time domain. And a project isstudied to show the dynamic response and the ground settlement of the heavyvehicle-bridge-ground system. Also the influencing factors are studied to find the rules ofthe vibration and the ground settlement. This paper is expected to provide a theoreticalreference for optimal design of bridge.