Purpose of paper. In July 2010, Alberta Transportation completed the installation of133 km of high tension median cable barrier (HTCB) on Alberta Highway 2, possibly the largest single such project to date in North America. EBA, A Tetra Tech Company, provided the design and construction supervision services and Alberta Highway Services Ltd. (AHS) was the construction contractor selected through competitive bidding. This paper presents an overview of the HTCB installation and with the help of photos, describes the relevant details of the innovations employed during construction which resulted in substantial cost savings and a record-breaking completion time. Note that the PowerPoint presentation of the paper at the conference included videos of the innovations. Summary of the innovations. The innovations utilized include the following: Use of driven steel (instead of concrete) for post and anchor foundations for the majority of the project length. New tools and techniques: o Vibratory post driver rather than the usual drop hammer technique. o Straight line production facilitated by hauling 20 cable spools per customized delivery truck rather than the usual four spools. o Special guide post attached to the front of a mini excavator to guide the cables off the truck. o Special tension-holding post to help take the slack out of the system. o Tensioning of cable with an electric winch attached to a mini excavator, instead of using a block and tackle arrangement. o Meticulous and detailed planning and execution of traffic accommodation. Positive results of the innovations. The positive results of the innovations included: The innovations allowed AHS to reduce the time required to install the entire 133 km of high tension cable barrier in 45 days compared to an estimated 150 days it would have taken with conventional methods and use of cast-in-place concrete foundations. There were no (zero) construction-related incidents within the construction zone during the installation on the busiest highway in Alberta carrying up to 80,000 vehicles per day. The contractor’s profit margin was significantly higher than the initial estimate. The client (Alberta Transportation) was highly satisfied with the process and the results.
