Development Of A Rapid Evaluation System For The Safety Of Heavy Rescue Vehicles Crossing Bridges

This paper addresses the problem of determining the feasibility of facilitating the swift and safe passage of heavy rescue vehicles through small and medium-sized bridges that have undergone long-term service and sustained damage.To tackle this challenge,the study utilizes Abaqus finite element software as the platform and develops a rapid evaluation system for assessing the safety of heavy rescue vehicles crossing bridges.The system comprises three main modules: a bridge finite element model rapid modeling module,a bridge finite element model correction module,and a heavy rescue vehicle crossing bridge safety rapid evaluation module.The key research objectives of this paper are as follows:(1)Design of the bridge finite element model fast modeling module: This module establishes a single girder model of the bridge’s finite element model by utilizing the bridge database as the data source.It combines the calculation of section characteristic values,the development of material intrinsic model subroutines,and the insertion of rebar keywords.Additionally,it incorporates a mobile vehicle load subroutine that incorporates the vehicle load characteristics to calculate the response of the vehicle load as it traverses the bridge.This module provides the essential data for both the bridge finite element model modification module and the heavy vehicle crossing safety evaluation module.(2)Design of the bridge finite element model correction module: This module employs bridge structure parameters as the correction objects and employs optimal Latin hypercube design sampling samples.The response surface model,known as the Kriging model,is utilized,along with the intelligent optimization algorithm known as the Skyhawk algorithm,to determine the correction variables that best represent the actual bridge structure.(3)Design of the heavy rescue vehicle crossing bridge safety evaluation module: Based on the finite element model of the bridge,this module calculates the live load effect,constant load effect,and the bearing capacity of the bridge section.These calculations are used to determine the bridge’s bearing capacity coefficient,which is crucial for evaluating the safety of vehicles passing through the bridge.(4)Case study on the safety of heavy rescue vehicles crossing bridges: A case study is conducted involving a 30-ton fire vehicle passing through a 25 m span prefabricated prestressed concrete simply supported beam bridge.Four distinct types of elastic modulus damage conditions are simulated.The bridge finite element model rapid modeling module is utilized for efficient modeling,while the model correction module is employed to refine the model accordingly.Finally,the safety evaluation module assesses the safety of vehicle passage across the bridge under the four damage scenarios.Furthermore,a 60-ton heavy fire vehicle passing through a four-span continuous box girder bridge is examined.The finite element model of the bridge is rapidly established,and the model modification module incorporates measured deflection influence line data to improve the accuracy of the finite element model of the box girder.Subsequently,the safety evaluation module evaluates the safety of vehicle passage across the bridge.