Over recent years, several Temporary Steel Barrier systems have been successfully crash tested in accordance with the AASHTO Manual for Assessing Safety Hardware and have demonstrated equivalent and in some cases superior performance toTemporary Concrete Barriers which have been traditionally used in Ontario. Temporary Steel Barriers have gained acceptance in Europe, Australia and other areas of North America and the construction industry in Ontario indicated an interest in using them on Ontario highway construction projects.
In response to this interest and the demonstrated functional equivalence of temporary steel and concrete barriers, the Ontario Ministry of Transportation sought to standardize the use of temporary steel barrier, which required a major re-write of its temporary barrier specification, shifting to the concept of a Temporary Construction Barrier. The Temporary Construction Barrier concept groups both concrete and steel barriers into four categories, based on their Dynamic Deflection when impacted under MASH TL-3 testing, with a corresponding tender item. Contractors are able to select from all systems that qualify for a given tender item. Most steel barriers require pinning into asphalt and some have been crash tested with different pin spacings, with more requent pin spacing resulting in a lower dynamic deflection. For three steel barrier systems, standard drawings were created for multiple pin spacing options which correspond to different Temporary Construction Barrier items.
The transition to Temporary Steel Barrier has been well received by the construction industry in Ontario and provides contractors with more flexibility and options for innovation on sites where temporary barrier is required. An added benefit of linking the appropriate tender item with dynamic deflection is higher quality designs as designers are required to consider available space behind barrier to excavations or fixed objects for a staging configuration.
