Every cable, pipe and service line that passes under a UAE road, industrial site and commercial development must have a place to sit — a place it can be protected from accidental damage, located when maintenance is required, and last long enough to last the life of the road, industrial facility or commercial development underneath. Precast concrete ducts perform that same function, and now serve as the industry benchmark in place of direct burial for the utility and service infrastructure throughout the region. In this guide, they will discuss what precast concrete ducts in UAE are, the different types of precast concrete ducts, what to look for in a supplier and what it takes to get from specification to installation.
What a Precast Concrete Duct Is and Why It’s Used
A precast concrete duct, or cable trough, is a manufactured trough, usually with a removable lid, used to install and protect underground services, including electrical cables, telecommunications lines, water pipes, gas lines and other services and utilities. Using a precast duct system protects, identifies and enables access to cables and pipes buried beneath the surface instead of directly in the ground.
The benefits of being installed by these methods are practical and not just theoretical. One of the advantages of a duct system is that it shields service lines from accidental damage to them in the event of any future excavation projects, and that can be a real possibility at an active construction site, or in urban areas. It enables rapid detection and rectification of wiring or pipework faults as the duct can be simply opened up for checking and repair, rather than excavating soil around the duct each time a fault is detected. Precast ducts are also produced in factory-controlled conditions, which ensures that they are structurally sound and dimensionally accurate, features that a site-built duct would not be able to attain.
The UAE has two more reasons for this. With the tremendous amount of underground utility infrastructure being installed in the nation’s rapidly expanding residential, commercial and industrial marketplace, ducts must be purchased in large quantities, and the soil and groundwater conditions in the region are generally saline and corrosive, making a durable, factory manufactured duct system a significant long-term option over direct burial or a less durable duct.
Types of Precast Concrete Ducts Available in the UAE
There are several types of Precast Concrete Ducts available in the UAE.
The specification of the duct will take into account the type of service that it will contain, the loading conditions over it, and the size of project.
Standard Cable Troughs and Ducts
The most popular design is a rectangular precast trough, that’s matched with a rectangular lid which is large enough to accommodate electrical cables, telecommunications lines or other services, and comes in a variety of standard widths and depth.
Heavy Duty Ducts for Vehicle Loading
Ducts designated for areas where vehicles travel should be structurally reinforced and, in many instances, a duct bedding material between the duct and the lid must be used to ensure a proper load distribution (this is not something to overlook when the duct is located under a road, driveway or trafficked yard area.)
Duct Banks for Multiple Services
When a number of cables or service lines are required in a single structure, often for substations, power distribution networks, and large-scale commercial or industrial electrical and networking infrastructure, the larger precast structures are used.
Customized Cable Trench & Utility Ducts
Made to custom size when standard sizes do not meet the project’s service needs, and some UAE manufacturers can provide bespoke sizing far beyond the range of their standard product offering to suit the needs of unique infrastructure projects.
Box Culvert Style Service Ducts
A service corridor for larger utility tunnels or multi-service corridors is attached below roads and infrastructure corridors using precast box culvert style ducts — offered in single, twin or multi-cell designs — which offer a larger walkable or crawl access service route.
Factors to Consider When Choosing a Precast Duct Supplier in UAE
There are multiple things to consider when choosing a precast duct supplier in UAE.
Ducts are a simple-sounding product with implications on structure and long term performance – a little diligence goes a long way.
Load Rating for the Application
Ensure structural rating is correct for the intended location; structural rating will vary depending on where the duct is placed, pedestrian areas, light vehicle traffic or heavy trafficked roads require different specifications. If the supplier is not asking questions regarding the loading environment before suggesting a product they aren’t doing the assessment right.
Standard Sizes vs. Custom Requirements
Inquire about the typical size range for their products and be sure they can make custom or bespoke sizes if the need in your service exceeds that.
Structural and Watertightness Specification
If you are considering ducts that will be installed in regions with high groundwater or saline soil conditions, inquire about the concrete grade and the measures that have been incorporated into the design to ensure the long-term durability of the duct in UAE ground conditions.
Lid Fit and Maintenance Access
A duct system is only as useful as the ability to access it — make sure the lid is secure, easily removable for maintenance and is designed correctly for loading conditions from above.
Multi-Service Compatibility
For services that are to be accommodated in the same duct, or where the duct is to carry multiple services with some cable runs, ensure that the design by the supplier can actually maintain the protection and access for each service.
Delivery and Bulk Order Capacity
With so many linear metres of duct that can be needed for a single project, verify the supplier’s production and delivery capacity with your project’s schedule and quantity.
Leading Precast Concrete Duct Suppliers in UAE
1. KKK Precast Concrete Industry LLC
KKK Precast produces precast concrete ducts and cable troughs, a part of its infrastructure and utility product line, in Dubai, Abu Dhabi and Sharjah, specifically designed to safeguard and facilitate access to underground electrical, telecom and utility service lines.
2. Naran Precast Concrete Co. LLC (NaranPCC)
Naran engineers create premium quality precast concrete ducts and cable troughs for heavy duty building projects in Dubai, which serve as a better alternative to direct burial in the ground as a cost effective solution offering protection to the service lines from environmental damage, easier identification and solving of wiring problems which contribute towards better power system distribution efficiency.
3. Zamac Precast
Zamac Precast, based in Umm Al Quwain, produces utility duct and trench drain products in a standard range of lengths from 3048mm long, widths from 508mm to 1525mm and internal heights from 254mm to 914mm, and also has the capacity to manufacture larger, non-standard sizes.
4. PRECAST UAE
PRECAST UAE produce RCC precast box culverts which are specific to UAE stormwater drainage, road crossing, service ducts and utility tunnels, in one, two and three cell designs, to project drawings in coordination of QA documentation and staged delivery of infrastructure scale projects.
5. Tri Star Concrete Products Factory
Tri Star produces a variety of precast concrete products for utility infrastructure in the UAE such as reinforced concrete cable route and joint markers that are installed next to duct systems to mark the location of underground service lines for future service or excavation protection.
The Precast Duct Supply and Installation Process
The sequence provides a better understanding and helps project planning for infrastructure based on precast duct systems.
Specification and Service Coordination
Duct size, load rating and services to be accommodated are verified on project drawings, the supplier makes their recommendations for standard or custom size as appropriate.
Manufacturing
Ducts and lids are cast and cured in the factory and checked for dimensional accuracy and structural specification prior to dispatch.
Trench Excavation
The trench is dug to the required depth and width with the base properly prepared to provide a level base for the duct sections to be applied evenly over the length of the run.
Placement
The duct sections are placed in the trench prepared, joined together in the appropriate trench direction and fitted with duct lids for future access without disturbing the surrounding ground.
Installing Cables or Pipes and Backfilling
Services are added at the end of the duct run, lids are closed and the duct area is backfilled around the duct structure using the appropriate bedding material under lids in trafficked or loaded areas.
UAE Approvals and Regulations for Precast Ducts
Precast ducts are also subject to UAE Approvals and Regulations.
Installations of ducts that are connected to the municipal utilities infrastructure or located under public roads are usually subject to approval by the relevant emirate authority such as Dubai Municipality, Department of Municipalities and Transport of Abu Dhabi, Sharjah Municipality, the RTA for infrastructure under road networks or the specific operator of the municipal utilities that it serves.
A contractor that has well established UAE infrastructure project experience will be aware of this and will be able to offer any documentation required to support the project sign-off.
Final Thoughts on Precast Concrete Duct Suppliers in UAE
The UAE precast duct market also features a range of duct suppliers, some with a wider product portfolio, such as cable troughs, which include KKK Precast and PRECAST UAE, and others with a more specific focus on cable troughs, such as Naran Precast, and those with a clearly defined size range for easy specification, such as Zamac Precast. To complete the line, Tri Star Concrete Products offers a full range of complementing cable marking products for use in the duct system during field installation.
Check the duct’s structural specification against the actual loading situation, make sure that the standard sizes meet the project’s specific service requirements, and only purchase a duct that you know is the right size for the job—don’t settle for a stock size if it doesn’t meet the project’s needs.