HEALTH & SAFETY ENGINEERING Conclusions Crash bollards are an effective security barrier measure to deter unscreened vehicles from accessing a protected site. Designing and testing of a crash bollard system before installing it is therefore essential to ensure that the bollard system is able to resist the impact loads and protect the desired assets. During the design-
ing process, utilising LS-DYNA as an analysis tool enabled us to visualise the structural response and failure mechanisms during the crash impact, which may have otherwise been overlooked if traditional static analysis methods are used. It also aids in optimising the design of the bollards and finalising the prototype product to be tested, effectively saving expense and time.
References [1] Paul Forman et al: ‘Vehicle-borne threats and the principles of hostile vehicle mitigation’, Blast effects on building, 2nd Edition, 2009. [2] UFC 4-022-02 (8 June 2009). Unified Facilities Criteria (UFC): ‘Selection and Application of Vehicle Barriers’. [3] ASTM F2656-07. Standard Test Method for Vehicle Crash Testing of Perimeter Barriers. [4] Joseph M Dulka et al: ‘Analysis and Design of a Unique Security Bollard Installment Using LS-DYNA for a K12 Vehicle Impact’, 13th International LSDYNA Users Conference, 2014. [5] S K Tay et al: ‘Crash Impact Modelling of Security Bollard’, 12th International LS-DYNA Users Conference, 2012. [6] B Hu et al: ‘Numerical Investigation of K4-rating shallow footing fixed antiram bollard system subjected to vehicle impact’, International Journal of Impact Engineering 63 (2014) 72-87. [7] NCAC. National Crash Analysis Centre http://www.ncac.gwu.edu/about.html [8] Ang Choon Keat, Professional Engineer (Civil), Singapore; Zoey Lim; Kong Jing Yan, ‘Test and Numerical Simulation of Fixed Bollard and Removable Bollard Subjected to Vehicle Impact’, 14th International LS-DYNA Users Conference, 2016, USA, June 2016.
Figure 6: Comparison of actual testing of vehicle impact and simulation model
Figure 7: Comparison of simulation results and actual test results
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[9] PAS68:2013. Impact test specifications for vehicle security barrier systems.