Any evening on Sheikh Zayed Road in Dubai, you’ll see something running down the middle of the road: kilometres of solid concrete slicing through opposing lanes of fast-moving traffic. It’s no coincidence that they’re designed like that. It’s a conscious, data-driven engineering initiative that is carried out with consistency across the ring roads in the UAE, from the highways of Abu Dhabi to the inter-emirate roads that connect Ras Al Khaimah.
Why does the UAE prefer the concrete over steel highway guardrails and/or cable barrier systems? The solution is based on the data from the road, engineering physics, climate realities and lessons learned from busy roadways around the world. This guide goes through it all.
The UAE Road Safety Context
In understanding barrier engineering, it is important to understand the road environment for which the barriers are designed.
Analysis of data from the UAE’s Ministry of Interior (MOI) by Road Safety UAE showed that the country suffered some 6,500 road accidents last year, with 384 deaths claiming the lives of 3.75 people per 100,000. That is significantly lower than the regional average, and nears a 40% reduction in the last decade – much of which has been attributed to infrastructure enhancements, such as improved median barrier systems.
Speeding is responsible for 13.1% UAE accidents. The wrong-direction driving and the improper overtaking combine to make up 4.9% of crashes. Divided highways: All three of these are potentially dangerous habits with the same outcome: getting into oncoming traffic. That is why a highway median barrier is put in place!
The roads of UAE are also really high speed. The speed limits on inter-emirate highways are often 120-140 km per hour, where if a driver crosses the centre divider into opposing traffic there is almost a guaranteed death. The median barrier system is not a pipe dream at these speeds. It is only a step away from a moment of driver error and a catastrophic event.
The Functions of a Highway Median Barrier and the Importance of Them
A Highway Median Barrier is a continuous barrier that is placed on the median of a divided highway to physically separate opposing traffic flows. Median barriers should be installed on fully controlled-access highways with a median width of about 9 metres (30 feet) or less and more than 20,000 vehicles per day are expected on the roadway. The UAE’s key roads fare well on both counts.
There are three types of barrier: concrete barriers, cable barriers and steel guardrail barriers, all of which have different physical characteristics, costs and performance. It’s not just that concrete is the preferred option in the UAE, it’s the engineering fit.
The UAE Is a Hot and Dry Area
1. Excellent Resistance to Deformation
2. Minimal Deformation After Impact
This is the fundamental engineering reason for the use of concrete.
A vehicle collides with a concrete barrier and is reflected, rather than absorbed. Concrete does not bend or yield — it would not allow the vehicle to keep moving along the same path into traffic lanes that are approaching them. Rigid Concrete Barriers are barriers that deflect little on impact, redirecting the vehicle rather than absorbing the impact energy, according to FHWA.
Unlike these, cable barriers are engineered to bend and snare a vehicle, absorbing the force of the impact along the way, and require true side clearance. In Dubai’s often tight medians, lack of space simply means there is not enough room for a cable to bend around the distance that would be required for an oncoming car to cross the median. Concrete does not require this: It will send the vehicle back on contact.
Narrow medians in UAE combined with high speed of traffic makes that zero-deflection feature a nice-to-have. It is an integral part of the geometry on which these highways were built.
3. The Data Is Both Cross-Medial and Shows for Itself
Median barrier performance is not subject to opinion and has been extensively studied. A number of studies have demonstrated that median barriers have been used to successfully prevent cross-median fatal collisions on high-volume freeways by over 97%. This is no incremental improvement, it’s almost a complete disappearance of one of the most lethal types of crashes on a divided roadway.
The Jersey barrier, the world’s most popular design of concrete median barrier, was designed specifically to prevent crossover collisions, and was developed in New Jersey in 1959. It has two slopes, which makes the wheels of a vehicle ride up slowly when they hit the ground, dissipating speed and restoring the vehicle to its lane without seizure and spin.
That containment performance is also reflected in UAE crash data, with wrong direction driving and high speed lane departure still being reported as crash causes, making it directly relevant to the UAE’s specific risk profile.
3. Concrete Wins in the Climate Game
The UAE has a hot climate – with summer temperatures often reaching over 45°C, and the saline and humid air in most of the coastal populated region increasing the rate of corrosion in metal structures. Cable barrier systems consist of steel cables and the posts that support them both of which can corrode with time, and need regular inspection, tightening or replacement — which is a lot more demanding in the hot weather and humidity of the UAE than in cooler climates.
Concrete barriers just don’t share that vulnerability. Precast concrete, if mixed and cured properly in conjunction with cement mixes developed to resist the alkaline soils and saline groundwater in the UAE, offers a long life and very little maintenance. In a harsh environment like the UAE, an added bonus of rigid concrete barriers is that they need relatively little maintenance or repair work over the course of their service life — a definite benefit in this particular instance, according to the FHWA.
Thermal expansion is also taken into consideration. The UAE wide temperature range from cool nights and extreme heat in the day time inspires the design of the road barrier, which is followed by leading UAE precast manufacturers to ensure the structural integrity in all conditions that the barriers may be subjected to during service.
4. Tight Urban Medians: Favour Rigid Barriers
The UAE’s urban highways, like Sheikh Zayed Road that runs through central Dubai, or the roads connecting the urban centres of Abu Dhabi, often are truly narrow, because the roads have been constructed in already built-up urban areas where space is limited.
FHWA guidance is clear on this – if there is not enough room to deflect, the solution is to use a rigid concrete barrier. For cable barriers to work, there should be 2–3 metres of space. A cable barrier in a 1-metre median is no safety barrier, it’s a barrier that doesn’t have space to do what it’s meant to do.
Concrete barriers, on the other hand, are dependable across nearly all medians, regardless of width. Even when the flow of traffic reaches a high speed of 120 km/h, a standard 600mm-wide concrete median barrier can effectively separate opposing lanes, while cable systems cannot.
5. Durability – Impact Without Routine Repair
A concrete barrier will not collapse or sag, or lose the ability to keep lanes separated, upon impact. It may chip and scuff off, but it does its job! That can be a significant issue for roads with thousands of cars a day, just a split second of protection is an unacceptable gap in safety — a damaged cable system is fixed or replaced, a guardrail section is replaced.
Cable barriers generally need repositioning or repair after a significant impact before they’re back to full function. When they are damaged, steel guardrails must be replaced in full sections. Concrete barriers, in almost all impact scenarios, continue to protect the road.
If it’s an authority with hundreds of kilometres of highway median, it’s no frills, it’s a real, quantifiable safety benefit.
6. Design Flexibility Throughout UAE Highway and Urban Areas
Not all median barriers are the same in the UAE. The local precast concrete barrier industry manufactures a variety of barriers for a variety of highway uses.
With its well known dual slope face, the 32-inch (81cm) Jersey barrier is still the world-wide standard for separating highways and is found throughout much of the UAE’s inter-emirate highways. This is improved by the F-shape barrier which has a lower break point between the slopes, which lessen the risk of a vehicle climbing and rolling over on higher speed roads. Single-slope barriers have a uniform face profile that is appropriate for areas where the roadway grades vary and a stepped profile is not required. The taller versions (to 1.07 metres) help to protect from light commercial vehicle crossovers and block oncoming headlight glare.
All of these variants are produced precast in the UAE and come in Jersey, F, single-slope and interlocking designs, designed to the municipal and RTA requirements for highway environmental conditions in the UAE.
7. Record of Performance in Response to the UAE Traffic Mix
UAE motorways have far from uniform traffic. The movement of trucks, tankers, construction vehicles and other heavy equipment between industrial areas and ports is also a significant activity on inter-emirate routes. A UAE highway median barrier must be able to safely confine not only misdirected cars but also big trucks.
The mass and rigidity of concrete are reliable in containing, regardless of vehicle type. A properly maintained and well-tensioned cable system will not prevent a loaded truck from breaking through, unless the impact conditions are just right. Concrete barriers are not as susceptible as other barriers, and at the standard dimensions used in the UAE (600mm wide x 800mm high) they are normally rated as approximately 2,100kg per barrier unit, and are capable of surviving impacts from heavy vehicles.
The Main Concrete Barriers Used on UAE Highways
By learning more about the different types of products used, it becomes easier to understand how the UAE highway authorities respond to various challenges of median separation.
The most common type on UAE highways is a Jersey barrier which has a shallow slope of 55° on its lower part, and a steep slope of 84° on its upper part that gently lift and slow the front wheel of a vehicle before redirecting it back into lane.
But F-type barriers, which lower the transition point between the slopes, enhance that same profile to better handle modern vehicles’ lower front ends, higher centres of gravity. F is usually the type that contractors are permitted by RTA to install in the higher speed zones of UAE roadways.
Single-slope barriers are appropriate for use where a uniform face profile is required instead of a stepped shape like Jersey — which is often used in elevated highway sections and crossings over bridges throughout the UAE.
Interlocking concrete barriers feature end connection systems to ensure panels are aligned with other panels on a barrier run that do not tend to drift out of alignment upon repeated low-speed impacts. In the UAE construction zone, these are found often.
Complies With Dubai Municipality and RTA Standards
Concrete road barriers in the UAE are not selected based on their looks only, they are created to the standards established by the road authorities in the UAE, such as Dubai’s Roads and Transport Authority (RTA) and Abu Dhabi’s Department of Municipalities and Transport, and similar authorities in the other emirates.
The standards include minimum concrete compressive strength (usually 35 N/mm² or higher), reinforcement specifications, dimensional tolerances and crash-test compliance. With these specifications, any barrier provided to a UAE highway project will be structurally sound, have been tested and certified to withstand the loads and impact conditions a concrete barrier is likely to encounter in a real project.
An Honest Look at the Trade-Offs
Concrete is not ideal, and there are compromises that must be addressed openly.
Cable systems are generally less expensive to install initially, and do not necessitate the large equipment (such as cranes and specialized trucks) used to install concrete barriers. Cable barriers are an effective option along the medians of wide, flat, well-maintained roads like rural roads between emirates.
But, given the UAE’s high-speed roads, thin urban vegetation, high volume of commercial traffic, corrosive climate and its lack of interest in continuous maintenance, the engineering argument for concrete is hard not to make. The UAE’s road authorities have reached just that conclusion and the amount of concrete barrier running across the country’s road network is the proof.
Final Thoughts
Choosing concrete highway median barriers is not a cultural norm or a habit in the UAE. It is the result of a straightforward engineering evaluation of the actual need for roads in the country.
Almost no deformation in the narrow medians. Almost elimination of the number of fatal cross-median collisions. Low maintenance requirements in hot and corrosive environment. Effective containment of heavy vehicles. Long life service with no significant maintenance. Combined, these represent a very powerful argument for the use of concrete as the material to divide traffic on the UAE’s highways.