Full text
| |
| Author(s): |
Renato Ramirez Viana Neves
Total Authors: 1
|
| Document type: | Master's Dissertation |
| Press: | São Paulo. |
| Institution: | Universidade de São Paulo (USP). Escola Politécnica (EP/BC) |
| Defense date: | 2013-02-01 |
| Examining board members: |
Marcílio Alves;
José Tadeu Balbo;
Heraldo Silva da Costa Mattos
|
| Advisor: | Marcílio Alves |
| Abstract | |
The main function of a road guardrail is to redirect an out of control vehicle avoiding a frontal collision or a dangerous veering off the road trajectory. Secondarily, the energy absorption measured by barrier deformation or any other energy dissipation method is beneficial to the car occupant safety. Considering the previous tasks and some severity occupant index like ASI, THIV and PHD, the performance of a guardrail and other concrete barriers are classified. Besides, it is investigated the fail mechanism of bolted connections and its influence on the guardrail impact result of an automobile. Special attention was taken into the material behavior modeling under low and high strain rates. Thereby, the need of accessing dynamic material properties motivated the design and manufacture of a Hopkinson Bar set-up for tension and compression tests up to 5000s-1. In addition, a simplified analytical model of a guardrail subjected to a static force was settled in order to validate a guardrail finite element model. A parametric study of the bolted connection failure was performed through several impact simulations of a light car model and a guardrail according to EN 1317 standard. The impact simulation results using a light vehicle car model and different barriers types were compared through the occupant severity index showing that the guardrail is a safer system than concrete barrier with New Jersey or vertical profile. (AU) | |
| FAPESP's process: | 10/04207-0 - Performance of guardrails subjected to impact loading |
| Grantee: | Renato Ramirez Viana Neves |
| Support Opportunities: | Scholarships in Brazil - Master |