Finite Element Analysis and Experimental Validation of Reinforced Concrete Single-Mat Slabs Subjected to Blast Loads
Abstract
The study carried out in this thesis is the investigation of the behavior of
reinforced concrete slabs subjected to blast loading. A separate experimental study was performed
involving twelve reinforced concrete (RC) slabs in a shock tube (Blast Load Simulator). Records
from this experimental study were used for performing finite element analysis. Numerical
simulation done in this research investigated the effect of using various bond-slip models in
studying the behavior of these twelve RC slabs subjected to blast loading.
LS-DYNA®, a non-linear transient dynamic finite element analysis program,
was used in this study. Finite element models for twelve slabs using the LS-DYNA® subjected to
experimental blast loads were used to study the bond-slip behavior between steel reinforcing bars
and concrete. High-strength concrete reinforced with high-strength steel slabs and normal-strength
concrete reinforced with normal-strength steel slabs were the two material combinations used in
this research. The primary objective of this study was the investigation of two bond interaction
system between steel and concrete, available in LS-DYNA®, for the two material combinations
under blast loading. The assumption of a perfect-bond between concrete and steel was the first
bond interaction system studied, utilizing Constrained Lagrange in Solid Formulation. Beam bond
is another bond interaction system investigated using Beam in Solid formulation in the program.
Furthermore, three functions were investigated in the beam bond interaction system along with the
program generated beam bond function. Validation of these interaction systems, with experimental
data, was the goal of the project.
Upon investigation of this research, comparison between results of the finite
element analysis and the experimental validation of reinforced concrete single-mat slabs which
were subjected to blast loading, assisted in the conclusion that the beam bond function proposed
by Murcia-Delso Juan is the most consistent among all of the interaction systems. However, with
slight modifications in the beam bond function proposed by Grassl, which is identical to the CEB
FIP model, gives the most accurate results for high strength materials in terms of peak deflection
and residual deflection history. Most accurate prediction to experimental records in given by
perfect bond formulation, and bond-slip fails to give accurate results for blast loading.
Table of Contents
Introduction -- Literature survey -- Objective and scope -- Experimental investigation -- Numerical modeling in LS-DYNA® -- Numerical Analusis results and comparison with experimental -- Discussion of results -- Conclusion and future work -- Appendix A. Pressure and impulse data for 12 slabs -- Appendix B. Pressure and impulse data for 12 RC slabs -- Appendix C. Summary tables -- Appendix D -- LS-DYNA input
Degree
M.S.