Cost-Effective Structural Anti-Ram Security Barriers: New Design, Computer Modeling and Test Validation

Author(s):  
Tarek Omar ◽  
Nabih E. Bedewi ◽  
Timothy Hylton

Terrorist attacks became a major threat to the safety, security, and economy of our nation in the last few years. The Attacks against important facilities could have different techniques; however the main source of ground attacks is the application of excessive amount of energy to the designated facility through a vehicle intrusion and/or a blast. In the current research, a new approach of using steel-structure barriers is presented. Several new structural anti-ramming barriers are designed and analyzed using nonlinear Finite Element Analysis (FEA). In this new design, commercial steel-structural components were used in order to reduce the manufacturing cost. These new steel-structure security devices have proven an excellent capability to sustain severe impacts by spreading substantial amount of the impact energy throughout the entire structure and the supporting soil/concrete. In the current research, three anti-ramming bollard systems, for K4, K8 and K12 impact conditions, were presented. The bollard systems were made of commercial steel unites connected together to produce the entire bollard structure. The FE modeling and simulation results of the bollard systems were presented in details in this paper. The FEA for the K4 bollard was validated by comparing the simulation results with the actual test results. The FE simulation results correlated very well with the actual test results. The steel-structure barriers could have much less shallow foundation to account for the in-city utility restrictions. It also has the advantage of easier and faster installation minimizing the required digging and installation time inside the city. The design could also be modified to account for different threat levels and different sites’ restrictions.

2011 ◽  
Vol 471-472 ◽  
pp. 634-639
Author(s):  
Mohd Khairol A. Arifin ◽  
Nik Mohd Idham Nik Hassan ◽  
Mohd Firdaus Abdullah

The study is intended to measure the reliability of MPV dashboard to endure interior impact by using finite element analysis (FEA) method. A model which represents MPV dashboard was made using Solidworks and the impact simulation was done using ABAQUS. Current material being used for dashboard is ABS-GF40 and this material was proven to be reliable to withstand interior impact through the simulation that has been done in this study. Besides, this study also serve the purpose to reduce manufacturing cost using alternative materials with no less reliability compared to ABS-GF40. Similar simulation routines were applied for ABS copolymer, PP copolymer, and PVC copolymer. The simulation results showed that ABS-CF40 performance is similar to ABS-GF40, whereas the PP-CF10, PP-GF10, and PVC-GF30 exhibit almost identical behavior under impact loading. Cost assessment was carried out for all materials to assist in selecting alternative material for replacement of ABS-GF40. Hence, it was found that PP-GF10 can be used as an alternative material with cost reduction up to RM33.17 on each dashboard.


2011 ◽  
Vol 308-310 ◽  
pp. 2527-2530
Author(s):  
Ke Zhang ◽  
Xiao Zheng Huang ◽  
Jian Ping Chen ◽  
Jin Fang Wang

The 6012 type aerial work platform is mainly used in the construction of steel structure occasions, and the overall and local stability of the studies to ensure construction safety and reduce accidents are of great significance. In this paper, I apply finite element analysis software ANSYS to model the hydraulic legs, and conduct static structural analysis of the hydraulic legs for 6012 type aerial work platform. At last, I will calculate the maximum deformation of single hydraulic legs and maximum stress of the situation in the maximum stress conditions, compared with the theoretical values and the actual test results.


2014 ◽  
Vol 1019 ◽  
pp. 143-151
Author(s):  
Carl J. Reinhardt ◽  
Morris Murray ◽  
Isaac Bohlken

High Quality Cost Effective Die Castings rely to a large extent on successful, effective and practical die design. A review is carried out of some runner and gate designs which resulted in successful high quality castings. Some High Pressure and Gravity cast casting are evaluated. Simulation results for evaluating the impact on the flow during filling due to Runner Geometries, Gate Geometries and positions as well as venting, overflows or risers are discussed. Thermal intervention through the use of internal thermal channels are also evaluated through the use of simulation results. The paper centres on a discussion of analysis of simulation results, predicting defects which impact on some aspects of surface finish and porosity. A case study is presented showing the value of following and taking heed of lessons learnt from simulation results, to carry out die designs with reduced reliance on simulation. Index Terms: South African Foundries, High Pressure Die Casting, Computerised Fluid Dynamics Simulation, Die Design, Defect Reduction.


2016 ◽  
Vol 2016 ◽  
pp. 1-10
Author(s):  
Fei Yao ◽  
Guangyu Chen ◽  
Jianhong Su

To identify shield grouting quality based on impact echo method, an impact echo test of segment-grouting (SG) test piece was carried out to explore effect of acoustic impedance of grouting layers and grouting defects on impact echo law. A finite element numerical simulation on the impact echo process was implemented. Test results and simulation results were compared. Results demonstrated that, under some working conditions, finite element simulation results and test results both agree with theoretical values. The acoustic impedance ratio of SG material influenced the echo characteristics significantly. But thickness frequency could not be detected under some working conditions because the reflected energy is weak. Frequency feature under grouting defects was more complicated than that under no grouting defects.


Author(s):  
Lin Deng ◽  
YongBing Li ◽  
Wayne Cai ◽  
Amberlee S. Haselhuhn ◽  
Blair E. Carlson

Abstract Resistance spot welding (RSW) of aluminum–aluminum (Al–Al) is known to be very challenging, with the asymmetric growth of the weld nugget often observed. In this article, a semicoupled electrical–thermal–mechanical finite element analysis (FEA) procedure was established to simulate the RSW of two layers of AA6022-T4 sheets using a specially designed Multi-Ring Domed (MRD) electrodes. Critical to the modeling procedure was the thermoelectric (including the Peltier, Thomson, and Seebeck effects) analyses to simulate the asymmetric nugget growth in the welding stage. Key input parameters such as the Seebeck coefficients and high-temperature flow stress curves were measured. Simulation results, experimentally validated, indicated that the newly developed procedure could successfully predict the asymmetric weld nugget growth. Simulation results also showed the Seebeck effect in the holding stage. The simulations represent the first quantitative investigation of the impact of the thermoelectric effects on resistance spot welding.


Author(s):  
Malcolm H. Ray

A method of comparing two acceleration time histories to determine whether they describe similar physical events is described. The method can be used to assess the repeatability of full-scale crash tests and it can also be used as a criterion for assessing how well a finite-element analysis of a collision event simulates a corresponding full-scale crash test. The method is used to compare a series of six identical crash tests and then is used to compare several finite-element analyses with full-scale crash test results.


2014 ◽  
Vol 852 ◽  
pp. 472-475
Author(s):  
Su Feng Zhang ◽  
Tian Lai Yu

This paper base on the actual form and structure of the original bridge piers actual data, according to the exposure collision theory and nonlinear finite element analysis theory, using LS-DYNA software, research the realationship of drift ice strength, modulus of elasticity, thickness factors with affecting convection ice impact force, while the drift ice impact force impact of the bridge was tested and simulated contrast. Simulation results show that the impact force with the flow of ice floe strength, elastic modulus, the increase of the thickness of the ice sheet was an increasing trend.


2012 ◽  
Vol 220-223 ◽  
pp. 1857-1860 ◽  
Author(s):  
Yun Bo Shi ◽  
Rui Zhao ◽  
Jun Liu

μAiming at the demand of missile fuse and other weapons systems, a high-g piezoresistive accelerometer with two terminal fixed beam-mass structure which can measure in-plane acceleration was designed. The design and simulation were also performed using Matlab and ANSYS. The simulation results show that the sensitivity of the accelerometer of sensitive-axis is 0.1101μV/g, and the transverse sensitivity of accelerometer is eliminated effectively. The key parameters such as impact over-loading signal and sensitivity of in-plane accelerometer were tested by Master hammer and Hopkinson bar. The test results showed that the sensor can work with the impact acceleration up to 117,395.95 g and the sensitivity of the accelerometer is 0.1028μV/g.


Author(s):  
S. N. Huang ◽  
S. S. Shiraga ◽  
L. M. Hay

This paper compares transportation mockup cask impact test results onto real surfaces with FEA numerical simulation results. The impact test results are from a series of cask impact tests that were conducted by Sandia National Laboratories (Gonzales 1987). The Sandia tests were conducted with a half-scale instrumented cask mockup impacting an essentially unyielding surface, in-situ soil, concrete runways, and concrete highways. The cask numerical simulations with these same surfaces are conducted with ABAQUS/Explicit, Version 5.8, The results are then compared and evaluated to access the viability of using numerical simulation to predict the impact behavior of transportation casks under hypothetical accident conditions.


Author(s):  
Hidekazu Takazawa ◽  
Kazuma Hirosaka ◽  
Katsumasa Miyazaki ◽  
Norihide Tohyama ◽  
Naomi Matsumoto

A new Japanese nuclear regulation requirement prepares estimating the possible damage to plant structures due to acts of terrorism, such as intentional aircraft impact. Aircraft impact needs to be considered in existing nuclear power plants. The structural damage and fuel splash behavior after aircraft impact into plant structures can be estimated using finite element analysis (FEA). FEA needs validated experimental data to determine the reliability of results. In this study, an analysis method was validated using a simple model such as a cylindrical tank. Numerical simulations were conducted to estimate the impact and splash behavior for a water-filled cylindrical tank. The simulated results were compared with the test results of the VTT Technical Research Centre of Finland. Simulations were carried out using a multipurpose FEA code LS-DYNA®. The cylindrical tank was modeled using a shell element, and filled water was modeled using a smoothed particle hydrodynamics (SPH) element. First, two analysis models were used to estimate the effect of the number of SPH elements. One was generated with about 300,000 SPH elements. The other was generated with 37,000 SPH elements. The cylindrical tank ruptured in the longitudinal direction after impact into a rigid wall, and the filled water splashed. Few differences emerged in the simulated results using different numbers of SPH elements. The impact test of the VTT was simulated with an arbitrary Lagrangian-Eulerian (ALE) element to consider the air drag. The analytical splash pattern and history of splash velocity ratio agreed well with the impact test results.


Sign in / Sign up

Export Citation Format

Share Document