Analysis Of A New Fence Type Blast Wall For Blast Protection

Current practice in designing the blast walls is based primarily on traditional concept of structural strength,ductility and energy absorption to resist the expected blast loads.Depending on the required protection level,usually these designs lead to huge structures which are not only rather expensive but also often not suitable for construction in urban areas.At the same time,the material properties of sandwiched blast walls are difficult to control,so it is difficult to design a high efficiency of the blast wall.The primary work and research results are as follows:This paper will explore the possibility of developing a completely new blast wall designs based on the concept of wave interference.Instead of using solid walls to resist the blast loads,the new design uses fence type structural columns placed at strategic locations as wave stoppers which could generate wave reflection,refraction and interaction between the reflected and refracted waves from different columns to cancel out wave energy.This innovative blast fence wall design is expected to increase the blast wall protection levels for people and structures behind the wall,and significantly decrease the construction costs of the blast walls.It might be also used in other types of blast resistant structures.In this thesis,this paper mainly studied three aspects.1?Theoretical research Based on the propagation mechanism of the physical wave,the classical wave theory is applied to analyze the propagation of one-dimensional and two-dimensional shock wave in air.The interaction mechanism between the explosive wave and the fence columns is studied by numerical simulation and classical wave theory.2?Numerical simulation Based on the two-dimensional numerical simulations,the optimized layout of the fence type blast wall is proposed from the numerical analysis that leads to the most significant blast loads reduction for different fence type blast wall.The numerical results show that,the fence wall with circular and isosceles right triangle columns are the most effective in canceling the blast waves.Based on the above results,three-dimensional numerical simulation is also carried out to study the interaction between blast wave and the blast walls for further validating the proposed optimized layout of the fence type blast wall.3?Experimental study To validate the effectiveness of the fence wall in blast reduction and based on the numerical simulations,the corresponding fence blast wall is made and the feasibility of the test scheme is put forward.Based on the experimental results the effectiveness of the proposed optimized layout of the fence type blast wall will be verified after that.