Impact of Truck on Bridge Piers

Project Description:

Understanding the damage modes of the bridge after the collision is an important point for the safety assessment and the subsequent impact on the local transportation network. Most of the work done to collect the data collects only stress and deformations under dynamic loads when the vehicles run on the deck. The impact by vehicle running is much lesser than the impact caused due to the collision of the vehicle with piers.
To study the impact first simulation should be done by taking a pier of a certain size, for example round rigid piers of 24in, 36 in and 48 in Dia. In reality, the non-linear damage can alter the force of impact and its estimation.

Project Implementation:

The implementation of this project starts with following simple steps:
1. To investigate the effect of the impact of the truck on piers, a finite element model of 3 spans non-continuous steel girder bridge is to be developed in LS-DYNA ( software ).
2. Element eroding technique has to be used to avoid severe element distortion while impact and each component of the bridge is designed and built in software.
3. CSCM material model is used for concrete structural components and plastic-kinematic model for rebars and steel girders.
4. A truck model of certain weight has been taken and built and evaluated. The components of the truck have been created through finite element software.
5. Then the simulation is run by combining the truck model to pier design in software and then the certain angle is set and with different velocities like 75mph,50mph etc. the simulation is run.
6. The result is obtained from the simulation after setting the boundary condition and the result data are compared with AASHTO specification and then the modification is done on materials properties and the simulation is run for multiple case scenario.

Project Requirements:

1. Hypermesh: required to do the meshing of the bodies used for the project.
2. LS-DYNA: used to do the analysis of the bodies at different conditons.

Project Scope:

This project can be carried out further by using the data of analysis to implement a new design of Piers or based on above performance we can improve the design of piers in following Steps:
1. Determining the impact speed of the trucks and determine the weight of the loaded truck.
2. Calculate the peak impact force when the truck hits the pier.
3. Determine the damage level from 0 to 5.
4. Determine the shear capacity of the bridge pier also known as static shear capacity.
5. Now design the rebar detailing or change the pier size to achieve the desired shear capacity.

• Hypermesh
• LS-Dyna
• Bridge design

• LS-Dyna
• Hypermesh
• Piers