RamShield® Edge
MASH TL4 Compliance on Weak Soil Embankments
RAMSHIELD® Edge
MASH TL4 Thrie-Beam Road Safety Barrier
RamShield® Edge is an engineered solution, designed for attachment to RamShield® High Containment for installations on the hinge point of weak batters. RamShield® Edge uses an innovative below-ground pin to restrain lateral movement of the guardrail post, allowing the post to yield by bending proximate to ground level, replicating post performance in flat, well-compacted terrain.
The RamShield® Edge pin is anchored in front of the barrier system therefore not relying upon lateral support behind the post. This restraint mechanism is independent of soil type, compaction level or batter geometry behind the post.
- MASH TL4 Compliant.
- Crash tested on the hinge point of a 1:1 weak soil embankment.
- Restraining pins are reusable following design impacts.
- Prevents below ground movement of the post.
- Standard post spacing: 2m centres.
Product Data Sheet
RamShield® Edge FAQ’s
How does RamShield® Edge Work?
RamShield® Edge is a variation to RamShield® High Containment (HC) providing MASH TL4 compliance for installations on the hinge point of a 1:1 weak soil embankment.
RamShield® Edge restrains the RamShield® HC posts by using a pin that is driven back into the road formation at approximately 45° and is clamped to the post just below ground level. The RamShield® Edge pin prevents below-ground post movement allowing the post to yield by bending at ground level, replicating post behaviour in flat, well-compacted terrain. RamShield® Edge prevents the post from rotating through the back of the embankment, limits barrier deflection and facilitates safe vehicle containment and redirection.
What crash tests have been performed with RamShield® Edge?
Crash testing of RamShield® Edge has been performed on the hinge point of a 1:1 weak soil embankment.
RamShield® Edge has been fully crash tested and evaluated according to the specifications for Test Level 4 (TL4) of the AASHTO Manual for Assessing Safety Hardware (MASH). The MASH specification is an update to and supersedes NCHRP Report 350 for the purposes of evaluating new safety hardware devices.
What is MASH?
The MASH specification is an update to and supersedes NCHRP Report 350 for the purposes of evaluating new safety hardware devices.
MASH presents uniform guidelines for crash testing permanent and temporary highway safety features and recommends evaluation criteria to assess test results.
MASH considers real-life crash data, changes to the vehicle fleet and in-service performance in developing evaluation criteria.
How are the RamShield® Edge pins installed?
The RamShield® Edge pin is anchored in front of the barrier system therefore not relying upon lateral support behind the post. This restraint mechanism is independent of soil type, compaction level or batter geometry behind the post.
What is the benefit of installing RamShield® Edge at existing sites?
RamShield® Edge is an economical alternative to expensive shoulder widening and embankment stabilisation. Positioning the barrier on the hinge batter conserves valuable vehicle lane width and retains important recovery space between the edge of the travelled way and the barrier.
What are the advantages of installing thrie-beam adjacent to embankments?
Thrie-beam system provides numerous performance advantages when compared with a w-beam system when installed near embankments. A thrie-beam system provides lower dynamic deflection, a wider lateral catching area and deeper post embedment when compared with w-beam systems. Furthermore, a higher rail height provides improved stability for high-centre-of-gravity vehicles and thrie-beam systems are less prone to vehicles under-riding the system.
