On the validation of the LS-DYNA Geo Metro numerical model

The paper presents experiences gained during work with numerical model of Geo Metro vehicle used for simulations of crash tests with road safety barriers. Attention is drawn to the subject of tire/wheel breakage during collision events. Some methods for improvement of the model are presented in the paper. Several results for the normative vehicle numerical tests are introduced. Simulations were carried out using LS-DYNA finite element code with solver version R8.1

Finite element method simulations of various cases of crash tests with N2/W4/A steel road barrier

The subject of this study is performance of N2/W4/A steel road safety barrier investigated in numerical simulations. System was checked under several types of initial conditions, which were assumed basing on the TB11 and TB32 normative crash tests. The main goal of present study is to investigate the relationship between initial conditions (angle and velocity) of the impact and the severity indices (associated to the vehicle occupant) during the collision. Obtained performance parameters and impact severity indexes may be considered reasonable. Results of the simulations facilitates the deep insight into vehicle crash mechanics phenomena

Finite element method simulations of various cases of crash tests with N2/W4/A steel road barrier

The subject of this study is performance of N2/W4/A steel road safety barrier investigated in numerical simulations. System was checked under several types of initial conditions, which were assumed basing on the TB11 and TB32 normative crash tests. The main goal of present study is to investigate the relationship between initial conditions (angle and velocity) of the impact and the severity indices (associated to the vehicle occupant) during the collision. Obtained performance parameters and impact severity indexes may be considered reasonable. Results of the simulations facilitates the deep insight into vehicle crash mechanics phenomena

On estimation of occupant safety in vehicular crashes into roadside obstacles using non-linear dynamic analysis

The article describes a comparison of two general methods of occupants safety estimation based on a numerical examples. The so-called direct method is mainly based on the HIC (Head Injury Criterion) of a crash test dummy in a vehicle with passive safety system while the indirect method uses a European standard approach to estimate impact severity level

Influence of the femoral offset on the muscles passive resistance in total hip arthroplasty.

BackgroundSoft tissue tension is treated as a crucial factor influencing the post-THA dislocation. The femoral offset is regarded as one of the major parameters responsible for the stabilization of the prosthesis. It is unclear which soft tissue is mostly affected by the offset changes.MethodsA finite element model of the hip was created. The model comprised muscles, bones, a stem, the acetabular component and a liner. The muscles were modelled as a Hill-type musculo-tendon nonlinear springs. Nonlinear analyses of the hip flexion and internal rotation were performed for the two values of the femoral stem offset.ResultsWe observed that the quadratus femoris and gluteus medius produce the largest resisting moment opposing the external load excreted by the surgeon during the intraoperative hip dislocation test.ConclusionsAn increased femoral offset increases the stretching of the quadratus femoris muscle significantly and provides the growth of its initial passive force. This muscle serves as a stiff band, providing stabilisation of the hip prosthesis, measured during the simulated intraoperative test

On the influence of the acceleration recording time on the calculation of impact severity indexes

The paper concerns with the analysis of normative requirements pertaining to experimental setup of a crash test and its numerical modelling. An overview of parameters describing the collision of a vehicle with a road restraining system is presented. A short description of a concrete road safety barrier is presented. A brief description of numerical modelling procedures for crash tests is given as well. The parametric influence analysis is performed of the acceleration recording time on various crash test functionality parameters The simulations are carried out using LS-DYNA finite element code with a solver version R.8.

On the validation of the LS-DYNA Geo Metro numerical model

The paper presents experiences gained during work with numerical model of Geo Metro vehicle used for simulations of crash tests with road safety barriers. Attention is drawn to the subject of tire/wheel breakage during collision events. Some methods for improvement of the model are presented in the paper. Several results for the normative vehicle numerical tests are introduced. Simulations were carried out using LS-DYNA finite element code with solver version R8.1

The influence of position of the post or its absence on the performance of the cable barrier system

Road safety barriers are used to increase safety in potentially dangerous places on the roads. They are designed and installed on the roads to prevent any vehicle from getting outside the travelled way or from entering the opposite lane of the road. Barriers, which are used on European roads, have to undergo full scale crash tests according to the EN 1317 standards. Nowadays as a supplement to real crash tests, numerical simulations are commonly used. The work concerns the influence of position of the post or its absence on the crashworthiness of the cable barrier based on numerical study results

The influence of position of the post or its absence on the performance of the cable barrier system

Road safety barriers are used to increase safety in potentially dangerous places on the roads. They are designed and installed on the roads to prevent any vehicle from getting outside the travelled way or from entering the opposite lane of the road. Barriers, which are used on European roads, have to undergo full scale crash tests according to the EN 1317 standards. Nowadays as a supplement to real crash tests, numerical simulations are commonly used. The work concerns the influence of position of the post or its absence on the crashworthiness of the cable barrier based on numerical study results

BADANIA NUMERYCZNE ZDERZENIA AUTOBUSU W UKŁADZIE BARIERA I KRATOWNICOWA KONSTRUKCJA WSPORCZA

Zdarzenia spowodowane wypadnięciem pojazdu z trasy stanowią 20 – 30 % ogółu zdarzeń niebezpiecznych na drogach. Najczęściej występującymi przeszkodami i niebezpiecznymi obiektami przy drodze, w które uderza wypadający z niej pojazd są: bariery na autostradach i drogach ekspresowych oraz drzewa, słupy i znaki drogowe na innych szlakach. Do opracowania metody projektowania, tj. doboru lokalizacji i rodzaju urządzeń bezpieczeństwa ruchu, potrzebne są badania poligo-nowe i symulacyjne funkcjonowania tych urządzeń w chwili uderzenia pojazdu. W pracy przedstawione zostały przykłady zastosowania badań numerycznych do symulacji pracy układu bariera drogowa i konstrukcja wsporcza znaku drogowego w przypadku uderzenia w nie autobusu