In search of the right precast permanent barrier supplier? A permanent barrier has one function: to remain in the same position forever – that is, until it is tested – and to absorb or resist impact reliably year after year without the maintenance and repositioning that temporary barriers are constructed around. If it does, it is not seen. When it doesn’t, the problem is not so much the concept of installing a permanent barrier as it is the manufacturer or designer of the barrier. This guide helps to assess a precast permanent barrier supplier so that you’ll have a structure that truly will protect you in the long haul and not fail at the last minute.
The Decision to Select a Supplier Is Not Just Based on the Length and Price Per Metre
The initial comparison is made by the most of the buyers with the barrier length, weight, and price per metre. That’s a good beginning, but it leaves out how it’s supposed to be engineered by the supplier to a known performance standard and how it is detailed for decades of weather and foundation settlement without loss of structural integrity.
A permanent unit has a long-term engineering calculation as opposed to a temporary unit, as permanent barriers are installed and expected to work for many years. These should be tough enough to resist years of the ground’s movement and weather cycling and the barrier must still be operating at full design capacity once it has been tested on the day of the impact, whatever that day may be. A supplier that considers permanent barrier design as a long-term structural investment, and not simply a “heavier version of a temporary barrier” plans and details for the whole of the life of the barrier. The individual who refuses to will give a wall that seemed solid on the day it was built, but will gradually become unreliable as the foundation, joint or reinforcement becomes compromised and goes unnoticed beneath the surface or underground.
Understand Exactly What Type of Permanent Barrier Your Project Requires
It is useful to understand the type of permanent barrier your project needs before comparing suppliers as the application and level of performance required is quite different.
Permanent Roadway and Median Barriers
Traffic is separated from traffic by permanent roadway and median barriers that require containment performance to be certified to a qualified roadway safety standard that is appropriate for the combination of traffic speed and volume on the roadway protected.
Permanent Perimeter and Anti-Ram Barriers
Perimeter and anti-ram barriers secure a fixed site from vehicle access on a permanent basis, for security or safety reasons. These should be installed in a permanent way, have a clearly specified resistance to car impact at a specific speed and weight, and should have a clearly defined anchoring and foundation.
Permanent Pedestrian Protection Barriers
Pedestrian protection barriers are barriers that are installed long-term to separate pedestrians from vehicle traffic, or hazardous areas, and do not necessarily need to resist significant impact of a vehicle. These focus on stable, long-lasting connecting foundations to barriers as opposed to the more dramatic engineering of vehicle-rated barriers.
Integrated Landscape and Streetscape Barriers
Integrated barriers provide protective and aesthetic qualities for permanent installations in public and commercial areas. These must not only perform properly but must also have a finish that is attractive, long lasting and weather resistant to meet the demands of the public as it is over a number of years and not just when it is installed.
With the category and performance level identified that fits the project, the list of suppliers can be reduced to manufacturers who can provide true and accumulated evidence of long-term performance for that category and performance level.
Inquire About Their Design Standard and Long-Term Performance Certification
A supplier who takes the manufacture of permanent barriers very seriously will be able to make it clear what recognised standard their barriers are designed and tested against and will be able to provide supporting evidence both for the initial performance rating and for guidance on the durability of the barriers over time. This is more important for permanent installations than temporary, as the barrier must maintain the certified performance for years, rather than just work on day one.
Ask these three simple questions to check the barrier’s standard or containment level, its design life and whether they can provide the actual certification documentation for the specific product you are purchasing. If a supplier does not hesitate to offer this service, it is one that is worth using. An unsure supplier, or one that couldn’t tell you about the long term performance of a design is not a supplier to trust for a permanent safety-critical structure.
Look at Their Foundation and Connection Design for Long-Term Stability
For a permanent barrier, as much as the barrier body itself, the foundation and connection detailing are important in that they are what hold the barrier up for years of ground movement, weather cycling, and even, potentially, previous minor impacts. Inquire about the foundation design for your site, how the barrier is attached to the foundation, and if that attachment type was tested in the original certified test.
A supplier that can explain how their foundation and connection design will help ensure the longevity of the product, rather than just its installation, is showing true engineering for a true permanent product. A supplier who considers foundation design to be a general pursuit without relation to the barrier’s guaranteed performance is filling a significant hole in the long-term reliability system.
Check Their Manufacturing Quality Control
On paper, the two barriers can be identical, but their durability in the long term varies depending on the way they are cast. Inquire about the ways units are cast, the curing process, curing time, and quality checks that occur prior to unit dispatch.
Where durability is a concern, as in a permanent installation, it’s important that the detailing be as significant as it would be for a temporary use, such as reinforcement cover to resist long-term corrosion, dense, well-cured concrete to resist weathering, and quality control of all units in the order. Specifically ask how the supplier’s manufacturing process provides for the intended multi-year service life of the barrier and provides it, not only its performance.
Do Not Accept a Standard Foundation Detail Without Site-Specific Engineering
A competent supplier will offer foundation engineering that’s appropriate for the underlying characteristics of your site and the load it’s subjected to, rather than an all-purpose foundation detail that merely works everywhere. This should be accompanied by confirmation that the design is appropriate to your specific soil bearing capacity, confirmation of design considerations of groundwater or frost (if applicable) and guidance on whether the installation should involve long term monitoring of settlement or maintenance.
Any supplier that can produce this much detail will alert the customer of site-specific problems before the permanent structure is installed and long-term adjustments and site changes have occurred. If a supplier provides just one standard foundation detail, no matter the conditions at the site, then you must thoroughly assess your own, and if there is any mismatch, you will be clueless.
Review the Installation Requirements and Long-Term Maintenance Guidance
The multi-decade service life of permanent barriers implies more heavy duty foundation construction than a temporary barrier. Ask their supplier for the foundation preparation and connection process they recommend, whether they can help with foundation preparation, whether they have guidance for installation, and whether they have experience working with contractors experienced in permanent barrier installation, and what (if any) long-term inspection and/or maintenance guidance they recommend to ensure the barrier performs as designed over time.
This will generally be apparent to a supplier when they are confident in the product they are providing for the long haul. If the supplier regards the barrier as a “fit and forget” product and does not consider it to be a permanent installation, he or she may have not taken all the factors into account that would be necessary for a real permanent installation.
Look into Their References and Track Record
The documentation and certification reveal the barriers of a supplier are intended to accomplish. For long-duration projects, you can learn from what they have actually provided over the years. Request case studies of long-term use of permanent barrier installations – foundation stability, no unexpected deterioration or continued certified performance.
Any claim about initial performance only is nothing compared to a supplier that has a proven, documented history of permanent barriers that have remained in place for several years.
Red Flags to Watch Out For
The few warning signs that reoccur with less reliable permanent barrier suppliers include:
- Certification data that only covers performance in the initial installation with no mention of long-term durability.
- A generic foundation detail that’s provided regardless of site conditions.
- No instruction provided on the maintenance or inspection of the permanent barriers.
- Pricing that is below what the more reliable suppliers charge for long-term durability.
If a permanent barrier is to be installed and is expected to stand for years or decades, and the consequences of failure are serious, then two or three of these warning flags in tandem should make you slow down and ask many more questions before you commit.
Integrating the Components of a Program
The selection of the correct precast permanent barrier supplier depends on the assurance of the supplier in designing the barrier for correct performance on installation day, as well as for the structural reliability over the entire multi decade service life with the appropriate certification, foundation and connection design, careful manufacture, and site specific design engineering behind each and every installation. Do all this correctly and it does what it’s supposed to: stays in place and works consistently from year to year and for as long as the site requires it.