Masonry structural damage and failure under blasting vibration

Shihai Chen,Zihua Zhang

doi:10.1177/1687814016633412

Abstract

Research on structural dynamic response and damage characteristics under blasting vibration is critical in structural safety assessment and blasting design. An orthotropic dynamic damage constitutive model of structural material is proposed in this article to improve the overly simple dynamic damage models of previous studies. A dynamic increase factor is used to assess the strain rate effect, and the dynamic damage stiffness matrix of the unit body is determined using the Sidoroff energy equivalence principle. The Mazars damage evolution model is used to calculate damage variables in the principal axis directions, and the Hoffman yield failure criterion for orthotropic materials is applied. The orthotropic dynamic damage constitutive model is input into dynamic finite element program LS-DYNA as the user subroutine to simulate the dynamic responses of typical masonry structures according to different blasting vibration excitations. The effects of varying particle peak velocity, principal frequency, and duration of blasting vibration on structural dynamic responses and damage are analyzed. The results show that maximal equivalent stress and strain increase positively with the particle peak velocity, structures have a danger frequency band, and structural damage increases with duration.

Highlights

With the increasing complexity of blasting environments and enhanced awareness of environmental protection and right, the negative consequences of blasting, especially vibration effect, have caused widespread concern
A typical time history of vertical blasting vibration measured by blasting vibration recorder (IDS3850) in a field test is used to analyze the effects of the three essential factors (PPV, principal frequency (PF), and duration) of blasting vibrations on the dynamic responses of the structure in this study
In order to simulate the dynamic responses of typical masonry structures under different blasting vibration excitations, the orthotropic dynamic damage constitutive model of structural material presented in this article is input into dynamic finite element program LS-DYNA as a user subroutine

Summary

Introduction

With the increasing complexity of blasting environments and enhanced awareness of environmental protection and right, the negative consequences of blasting, especially vibration effect, have caused widespread concern. The model is input into dynamic finite element program LS-DYNA as a user subroutine to simulate the dynamic responses of typical masonry structures under different blasting vibration excitations. The vibration load in the vertical direction is often used as the failure criterion for the structure according to the Blasting Safety Regulations.[24] A typical time history of vertical blasting vibration measured by blasting vibration recorder (IDS3850) in a field test is used to analyze the effects of the three essential factors (PPV, principal frequency (PF), and duration) of blasting vibrations on the dynamic responses of the structure in this study. In order to simulate the dynamic responses of typical masonry structures under different blasting vibration excitations, the orthotropic dynamic damage constitutive model of structural material presented in this article is input into dynamic finite element program LS-DYNA as a user subroutine.

Introduction of damage contours to structure

Conclusion