L. Bank, T. Gentry, Jiansheng Yin, J. D. Lamtenzan
{"title":"DYNA3D Simulations of Pendulum Impact Tests on Steel Guardrails","authors":"L. Bank, T. Gentry, Jiansheng Yin, J. D. Lamtenzan","doi":"10.1115/imece1996-1014","DOIUrl":"https://doi.org/10.1115/imece1996-1014","url":null,"abstract":"\u0000 The response of a G4(1S) strong post steel w-beam guardrail system to dynamic impact has been investigated in a series of full-size physical tests and in simulated experiments using LLNL-DYNA3D. The physical tests were conducted at the Federal Outdoor Impact Laboratory (FOIL) at the Turner Fairbank Highway Research Center of the Federal Highway Administration (FHWA) in McLean, Virginia using a pendulum. In the pendulum tests, an 880 kg mass was used to strike the rail perpendicular to its face. The rail section was attached to steel posts and blockouts and supported in a specially designed fixture. Initial velocities of the pendulum at impact were 9.25, 20, 30 and 35 km/h. From acceleration data taken during the testing, acceleration, force, velocity and displacement histories of the impact event were calculated. Data from the LLNL-DYNA3D simulations of the impact tests compared well with the data obtained from the full-scale testing. Animations of the deformed shapes of the rails at 25 msec intervals compared favorably with high speed film images. Force versus displacement histories showed good agreement with those obtained from quasi-static experiments.","PeriodicalId":102994,"journal":{"name":"Crashworthiness and Occupant Protection in Transportation Systems","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124449812","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Crush Behavior of Spot Welded Hat Section Components With Material Comparison","authors":"T. Omar, C. Kan, N. Bedewi","doi":"10.1115/imece1996-1015","DOIUrl":"https://doi.org/10.1115/imece1996-1015","url":null,"abstract":"\u0000 The computer aided design of vehicle steel alloy structures is well understood and fairly reliable. Finite element (FE) models for crash analysis, in both frontal and side impact, can be developed with high degrees of fidelity, and are playing a major role in automotive design today. The substitution of aluminum alloys in the load bearing components has added a level of complexity in the FE modeling. Issues related to validation of material constitutive models, failure modes, fracture and general material modeling have to be addressed in these new materials.\u0000 This paper describes the results of a study conducted to investigate and compare the crush performance of mild steel and aluminum alloy in main frontal load bearing vehicle components. Finite element models of spot-welded hat section stub columns were created and numerically simulated using the non-linear dynamic code LS-DYNA3D. Recommendations are provided for both FE models and simulation parameters in order to obtain an accurate and fair representation of the real test. Much of the analysis is obtained on optimization of results with respect to computation time. The crush behavior of hat section stub columns was studied under quasi-static and dynamic loading rates and then validated against published experimental results. Two different steel alloys and two different aluminum alloys have been used in the analysis. The strain rate effect has been considered for the steel alloys under two crushing rates of 8 m/s and 12 m/s. The mathematical modeling of resistance spot-welding joints in aluminum was also considered. Parameters as energy absorption, peak crush load capacity, and the crush distance are used to compare the crush behavior of steel and aluminum alloys in the main load bearing components.","PeriodicalId":102994,"journal":{"name":"Crashworthiness and Occupant Protection in Transportation Systems","volume":"363 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133973890","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Analytical Studies of Airbag System Design for Side Impacts","authors":"J. T. Wang, Yih-Charng Deng, G. Ressler","doi":"10.1115/imece1996-1018","DOIUrl":"https://doi.org/10.1115/imece1996-1018","url":null,"abstract":"\u0000 In this paper, we present an analytical study of design optimization of side airbag systems with respect to three chosen driver-side-like prototype inflators. An airbag/SID model has been developed in CAL3D. This model was used with a CAL3D design optimization program to identify airbag designs that met all FMVSS 214 requirements, assuming the feasibility of developing such a system in hardware. The results of this study were then used to guide the experimental work of side airbag system development.","PeriodicalId":102994,"journal":{"name":"Crashworthiness and Occupant Protection in Transportation Systems","volume":"186 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1996-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121623838","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}