Road Safety Barrier Systems Accepted for use on roads managed by the Ashghal

Public Works Authority (PWA)

Version 2 - March 2015

i

Department: Roads Operations & Maintenance (Asset Affairs)

Version No: OM-PPQ-RSB-002

Version Date: 08/03/2015

ROAD SAFETY BARRIER SYSTEMS

Accepted for use on roads managed by the Ashghal

Public Works Authority (PWA)

ii

CONTENTS

Selection of Road Safety Barrier Systems

New Products & Amendments

Safety Barriers - Permanent (Rigid Barriers)

Safety Barriers - Permanent (Semi-Rigid Barriers)

Safety Barriers - Permanent (Flexible Barriers)

Safety Barriers - Temporary

End Terminals

Crash Cushions - Permanent and Temporary.

Transitions

Vehicle Attenuators (TMAs)

Gates

Parapets

Miscellaneous

Appendix A: Summary of EN1317 Criteria

Appendix B: Crash Test Containment Levels and Conditions

Ashghal | Road Safety Barrier Systems | OM-PPQ-RSB-002 | March 2015 Page 1

Selection of Road Safety Barrier Systems

This document specifies public domain and proprietary longitudinal road safety barrier systems and

other crashworthy devices such as crash cushions and vehicle attenuators that are accepted for use on

roads managed by Ashghal Public Works Authority (PWA). Longitudinal safety barriers can be classified

into three types as follows:

(a) Rigid

(b) Semi-rigid

(c) Flexible

The selection, design, installation and maintenance of longitudinal road safety barriers must consider the operation of the barrier as an entire system. This includes all additional components such as end terminals, crash cushions, transitions and gates. All road safety barriers installed on the road network must be installed and maintained by qualified personnel.

The manufacturer or supplier of a proprietary road safety barrier system shall provide all necessary

details for verification of crash performance, characteristics and limitations of the system and

requirements on the fabrication, installation, maintenance and refurbishment of the system.

All road safety barrier systems must be deemed to be in accordance with EN1317, NCHRP350 and/or

MASH and approved by the PWA. The primary criterion for the approval of a barrier system is that it

must have been successfully crash tested and the results evaluated in accordance with EN1317.

However, consideration will also be given to systems that have been successfully crash tested in

accordance with NCHRP350 or MASH.

In addition, consideration will be given to other factors including but not limited to the following:

In-service Performance: In the case of a system with no demonstrable in-service history

an in-service trial may be required, at the manufacturer /

suppliers cost or as otherwise agreed with the PWA.

Availability of Spare Parts: The manufacturer / supplier will need to demonstrate that

spare parts are available for maintenance / replacement within

an agreed timeframe.

The selection of road safety barrier system for a particular site is based on the performance of the

system under crash test conditions. The objective of the testing is to determine the manner in which the

barrier system is likely to perform during a vehicle crash.

The primary criteria to evaluate the safety performance of a barrier system include structural adequacy

(containment level), occupant risk (impact severity), deformation of the system (working width or

deflection) and the post impact vehicle response.

Ashghal | Road Safety Barrier Systems | OM-PPQ-RSB-002 | March 2015 Page 2

These criteria are summarised below:

(a) Containment Level

The tested barrier system must contain and redirect the vehicle in a safe manner. The vehicle should not penetrate, under-ride or over-ride the installation. It is important to note the vehicle types and test conditions for each containment level when selecting the type of barrier protection required. EN1317 sets out criteria for normal containment (N1 and N2), higher containment (H1 to H3) and very high containment (H4a and H4b). Refer to Appendices A and B. NCHRP350 and MASH set out criteria for test levels 1 to 6, with TL6 providing the highest level of containment (refer to Appendix B).

(b) Impact Severity

Detached elements, fragments, or other debris from the test article should not penetrate the occupant compartment or present an undue hazard to other traffic. The impact severity level for safety barriers shall be as low as practicable to reduce the risk to vehicle occupants. For systems tested to EN1317, impact severity level A shall be preferred over level B, and levels A and B preferred over level C (Appendix A). For systems tested to NCHRP350 or MASH, lower values for Occupant Impact Velocity (OIV) and Occupant Ridedown Acceleration (ORA) are preferred.

(b) Working Width / Deflection

Controlled lateral deflection of a barrier system is generally acceptable. However, this deflection and additional vehicle rotation over the barrier must be considered when selecting a barrier system for a particular site. Consideration needs to be given to the amount of barrier deflection under test conditions with roadside hazards being located beyond the specified working width or maximum deflection zone.

(c) Post Impact Vehicle Response

After a collision, it is preferable that the vehicle's trajectory does not intrude into adjacent traffic lanes. Evaluation of the safety performance of roadside hardware is based on actual crash testing.

Refer to Appendix A for a summary of EN1317 crash test criteria. Refer to Appendix B for a comparison of EN1317, NCHRP350 and MASH crash test containment levels and test conditions.

References:

European Committee for Standardisation (CEN) European Norm (EN) 1317 Road Restraint Systems (Parts 1-8), 2010

NCHRP 350: Recommended Procedures for the Safety Performance Evaluation of Highway Features. National Cooperative Highway Research Program Report 350 by: H E Ross Jr, D. L. Sicking, R A Zimmer and J.D. Michie, Transportation Research Board Washington DC, 1993

MASH: Manual for Assessing Safety Hardware, First Edition by D L Sicking. et al, American Association of State Highway and Transportation Officials, Washington DC, 2009]

Ashghal | Road Safety Barrier Systems | OM-PPQ-RSB-002 | March 2015 Page 3

New Products & Amendments

Previous version (Version 1): OM-PPQ-RSB-001 (14/04/2014)

This section will provide a summary of new products added to the list and details of any significant

amendments to the previous version:-

1. SLED (Sentry Longitudinal Energy Dissipater) Temporary Crash Cushion Added to section Crash

Cushions.

The SLED is a narrow, water-filled, non-redirecting, gating crash cushion which has been successfully

tested in accordance with NCHRP 350 Test Level 3 for use as an end treatment to steel and concrete

barriers under temporary conditions.

Note: - (1) The system is only to be used on projects for a duration of one month or less unless otherwise

approved by the Ashghal Traffic Diversion Plan (TDP) Approvals Office.

(2) Because the SLED is a non-redirecting, gating crash cushion, it should be applied in locations

that are not likely to be impacted at an angle on the side at any significant velocity;

(3) The approved product supplier (Refer section for details) remains responsible for ensuring

that Contractors have the necessary knowledge and skills to correctly use the product;

(4) The minimum acceptance configuration for use is the 4 module TL3 configuration unless

specifically approved as a departure by the Ashghal TDP Office;

(5) For full details of usage requirements for this product refer to Ashghal Acceptance Letter

dated 07-12-2014.

2. Imeva H2BL900 Permanent Safety Barrier- Added to section Permanent (Semi-Rigid Barriers).

The Imeva H2BL900 is a Semi-Rigid type Permanent Safety Barrier which complies with EN 1317-2

standard H2W5, ASI-A level.

Note: - Seek guidance from Roads O & M Department for approved installer details

3. SAFEROAD RRS Permanent Safety Barrier- Added to section Permanent (Semi-Rigid Barriers).

The Saferoad Road Restraint System is a Semi-Rigid type Permanent Safety Barrier which complies with

EN 1317-2 standard H4bW4, ASI-A level.

Note: - Seek guidance from Roads O & M Department for approved installer details

Ashghal | Road Safety Barrier Systems | OM-PPQ-RSB-002 | March 2015 Page 4

Safety Barriers - Permanent (Rigid Barriers)

System Type

System Name / Details Post Spacing

(m)

Containment Level

Working Width / Deflection

ASI

Supplier / Manufacturer Approved Installer

Acceptance Status / Comment

Permanent Safety Barrier Rigid (Concrete)

F-Shape Concrete Barrier

n/a

n/a

NCHRP350

TL4 (H* = 810mm)

TL5

(H*= 1070mm)

Public Domain FHWA Acceptance Letter B-64 and AASHTO-AGC-ARTBA Joint Committee, Task Force 13 Report: A Guide to Standardized Highway Barrier Hardware May 1995: System Drawing SGM10a-b

Refer to Interim Advice Note 002 (IAN-002) for details on concrete barrier use and performance. Refer to Ashghal Standard Drawing No: (Under Developm