Failure Rate of Empty and Fluid-Filled Concrete Pipes under High Strain Rates

Subject Areas : structural design

Asadollah Ranjbar Karkanaki ¹ , Mohsen Parviz ² , Alireza Darvishpour ³ , Mahyar Taheri ⁴

1 - Department of Civil Engineering, East Tehran Branch, Islamic Azad University, Tehran, Iran
2 - Structural Engineering, Iranian Academic Center for Education, Culture and Research (ACECR), Bushehr Branch, Iran.
3 - Department of Civil Engineering, Robatkarim Branch, Islamic Azad University, Robatkarim, Iran.
4 - Ph.D student, Depart, of Civil, Architectural and Environmental Engineering, Missouri University of Science and Technology, USA.

Received: 2023-05-29 Accepted : 2023-08-22 Published : 2022-08-01

Keywords: LS-DYNA, Strain rate, Model failure, Concrete pipes, Lagrangian-Eulerian Method,

Abstract :

Considering the importance of the performance of buried concrete pipes under external loads and the role played by concrete specifications and pipe thickness in this regard, the current study analyzed the failure rate and response of concrete pipes buried in three types of soil to a TNT blast load using the Lagrangian-Eulerian method in the nonlinear dynamics software LS-DYNA. The results show that the presence of fluid in the pipe generates an internal pressure, which reduces the deformation of the pipe under the blast load. It was also found that the higher the P-crush of the concrete pipe, the smaller the strain and displacement generated under the blast pressure. In thicker pipes, sometimes the damage is limited to the outer sections of the shell, and the pipe remains usable. However, in thinner pipes, damage often affects both inner and outer surfaces of the shell, rendering the pipe unusable. The plastic strain generated in Specimen 1 in Soil Type 1 is 85% higher than the acceptable plastic strain of the concrete pipe. Moreover, this value is 87% for Soil Type 2 and 85% for Soil Type 3.