Suchergebnisse

The computational simulation of detonation phenomena to construe the damage caused to urban structures is studied in this work. The theoretical approach to approximate the detonation shockwave and the mathematical formulation related with the Discrete Element Method (DEM) are discussed rst, then the test proposed to simulate detonations over structures is explained. The parameters assigned to characterize the structural physical properties corresponds to the most widely used materials to build civil constructions and public spaces. The damage analysis is focused on the structure sti ness, load capacity and lost of the mesh cohesive bonds after the shockwave impact. Multiple numerical simulation results of several scenaries with di erent explosive load masses and sundry distances between the structure and the detonation origin are studied in order to generate vulneravility curves, which will allow to know the expected damage of buildings when the only information available are the building material physical properties, the distance from the detonation and the explosive load mass. Finally, an index of damage after detonation (IDAD) is proposed to classify an incident and to understand easily the potentially hazard of a given detonation. Establish information about eventual catastrophic scenarios to support the decision making is the main purpose of this work, contributing with the Design Safer Urban Spaces (DESURBS) project, which is sponsored by the European Union and the Seventh Framework Programme (FP7) of the Research and Innovation European Commission, and supported by the International Center of Numerical Methods in Engineering (CIMNE) among other research centers.

Within this paper we discuss a numerical strategy to solve the elasticity problem upon unstructured and non conforming meshes, allowing all kinds of flat-faced elements (polygons in 2D and polyhedra in 3D). The core of the formulation relies on two numerical procedures 1) the Control Volume Function Approximation (CVFA), and 2) the polynomial interpolation in the neighborhood of the control volumes, which is used to solve the surface integrals resulting from applying the divergence theorem. By comparing the estimated stress against the analytical stress field of the well known test of an infinite plate with a hole, we show that this conservative approach is robust and accurate. ; The present investigation was sponsored by a CONACYT scolarship from the Mexican government and the TCAiNMaND project, an IRSES Marie Curie initiative under the European Union 7th Framework Programme. In addition, the authors want to express his gratitude to MSc. Ernesto Ortega, and to Drs. Rafel Herrera and Joaquin Peña for his insightful commments and discussions during the elaboration of this paper. ; Peer Reviewed ; Postprint (published version)