How to use the Guard Rails

Only pounds per foot % lighter than the standard s by. post a flanks channel post and soil plate made of rear old rail steel would cost about half as much as the standard g post in soil plate cable Sydney guard rails system cost almost $ per linear foot less than the g guardrail in distressed of the Sydney guard rails system the cables wrap around the front corner of the small car.

When it hits the barrier the cable slips off the post ahead of the collision and the posts either snap off or bend over as they're struck by the car the cables redirect the car parallel to the barrier it comes to a controlled stop after breaking in another test this large car travels about feet past the barrier line before being redirected parallel to the guardrail the performance of this system is similar to the cable Sydney guard rails system.

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The location of the guardrail on slopes is an important design consideration if the guardrail is located on the slope but too close to the edge of the pavement the cables may contact the vehicle below the front bumper allowing the car to ride over the cables and penetrate the barrier if the Sydney guard rails is placed at least feet away from the pavement the vehicle has more time to stabilize before it strikes the cables in this test the vehicle suspension had returned.

Its normal position when the car struck the cables the cables wrapped around the car just above the front bumper allowing the Sydney guard rails to redirect the vehicle this cable transition to a bridge rail is unsafe because it would redirect the vehicle into the rigid end of the bridge when two longitudinal barriers with different stiffness’s are joined there must be a smooth transition to avoid pocketing accidents a transition between a three cable Sydney guard rails and a w beam guardrail was developed to solve this problem.

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The post spacing of the cable system is reduced near the transition and the cables are passed over and under the W beam to a concrete anchor buried behind the W beams breakaway cable terminal the large car strikes the cable system and deflects about four feet before it strikes the end of the breakaway cable terminal the vehicle quickly redirects after striking the W beam system steel is not the only material that can be used for posts cable Sydney guard rails with wooden posts have been used by some states for decades recent tests evaluated a modification of the Minnesota state standard design that uses a five and a half inch diameter post with a one and a half inch hole drilled through it five inches below the ground.

This hole helps to weaken the post in the longitudinal direction ensuring that it breaks away when hit head-on the post spacing used is twelve feet six inches rather than the feet as is typical for g systems this small car was successfully redirected without exceeding the allowable occupant response values the system was also strong enough to contain and redirect this large passenger sedan the maximum barrier deflections were comparable to the standard g system in these two tests as with all types of longitudinal barriers designing effective in treatments for cable Sydney guard rails has been a difficult problem vehicles tend to stay in contact with cable guardrails longer than other barrier systems this is generally desirable but as posts are weakened to soften

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