Impact of roadside features on the frequency and severity of run-off-roadway accidents: an empirical analysis

A steering column assembly for a vehicle, comprises a shroud comprising an axially movable upper portion and an axially fixed lower portion, which move telescopically to provide adjustment for reach of the steering column assembly, a steering shaft supported by the shroud, a pivot which connects a part of the lower portion to a fixed part of the vehicle, a clamp mechanism which releasably fixes the upper and lower portions and the shroud in position relative to a further fixed part of the vehicle. A sprung support assembly is secured to a fixed part of the vehicle and includes an axle that passes underneath the upper portion of the shroud and a cylindrical roller that surrounds a part of the axle and has an outer surface that engages the underside of the shroud and an inner surface that bears on the axle, the sprung support at least partially supports the weight of the shroud when the clamp mechanism is released, and the cylindrical roller rotating around the axle as the shroud is adjusted for reach.

Steering column assembly

A latent segmentation based generalized ordered logit model to examine factors influencing driver injury severity

https://www.injurytriallawyer.com/library/The-crash-severity-impacts-of-fixed-roadside-objects.pdf

The crash severity impacts of fixed roadside objects.

Finite element modeling mesh quality, energy balance and validation methods: a review with recommendations associated with the modeling of bone tissue.

The performance of many guardrail terminal systems is dependent on the strength of timber guardrail posts and soil conditions. Accurately simulating the breakaway characteristits of guardrail posts mounted in soils is an important issue concerning researchers in the roadside safety community. Finite-element analysis is one method that can be used to evaluate roadside hardware designs, but good simulations are contingent on developing accurate models of the components. A description is provided of the development of a model of a breakaway timber post and soil system used in the breakaway cable terminal (BCT) and the modified eccentric loader terminal (MELT). The model is described and simulation results are compared with data from physical tests of BCT/MELT posts.

Finite-Element Modeling of Guardrail Timber Posts and the Post-Soil Interaction:

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.

Repeatability of Full-Scale Crash Tests and Criteria for Validating Simulation Results:

Finite element analysis has been used in roadside safety research for nearly three decades. Early applications used simple discreet-element special-purpose codes to predict gross deflections of guardrails and bridge rails in collisions with motor vehicles. More recently general purpose nonlinear explicit finite element programs have been integrated into the analysis and design of roadside safety hardware. This paper reviews the history of the use of finite element methods in roadside safety research and presents the current status of many of the vehicle, occupant and roadside hardware models that have been developed to date.

/pdf/the-use-of-finite-element-analysis-in-roadside-hardware-48k6s85e9f.pdf

The Use of Finite Element Analysis in Roadside Hardware Design

The weak-post W-beam guardrail has been widely used in the Northeast for many decades. Weak-post guardrails are characterized by larger dynamic deflections in a collision and are considered more forgiving than other, stiffer barriers. Most states have experienced good performance with these barriers over the last several decades if adequate clear space is provided behind the barrier. Unfortunately, recent crash tests of the standard weak-post W-beam guardrail involving a 2000-kg pickup truck resulted in a series of unacceptable test results, including overriding and penetrating the guardrail. Design modifications to the weak-post W-beam guardrail were explored by using finite element simulations and full-scale crash tests. An improved version of the weak-post W-beam guardrail system was developed and tested, and this was found to satisfy the requirements of NCHRP Report 350 for Test Level 3.

Improvements to the weak-post W-beam guardrail

Several types of strong-post W-beam guardrails are used in the United States. Usually the only difference between one type of strong-post W-beam guardrail and another is the choice of post and block-out types. The impact performance of two very similar strong-post W-beam guardrails are compared—the G4(2W), which uses a 150 x 200 mm wood post and the G4(1W), which uses a 200 x 200 mm wood post. Although G4(2W) is used in numerous states, G4(1W) is now common only in the state of Iowa. The performance of the two guardrails has been presumed equal, but only one full-scale crash test has been performed on G4(1W) and that was over 30 years ago, using a now-obsolete test vehicle. The nonlinear finite element analysis program LS-DYNA was used to evaluate the crashworthiness of the two guardrails. The G4(2W) guardrail model was validated with the results of a full-scale crash test. A model of the G4(1W) guardrail system was developed, and the deflection, vehicle redirection, and occupant risk factors of the two g...

Malcolm H. Ray

Papers

Finite-Element Modeling of Guardrail Timber Posts and the Post-Soil Interaction:

Repeatability of Full-Scale Crash Tests and Criteria for Validating Simulation Results:

The Use of Finite Element Analysis in Roadside Hardware Design

Improvements to the weak-post W-beam guardrail

Impact performance of the g4(1w) and g4(2w) guardrail systems: comparison under nchrp report 350 test 3-11 conditions