Abstract Manager

11 Street NE is a new interchange currently under construction on the Stoney Trail ring road in Calgary, Alberta. Initially constructed with the NW section of the ring road between 2005-07 the interchange was only pre-graded including the supporting stormwater management facilities.  Development to the north has now triggered the design and construction of the interchange, with the need to account for updated design standards, a future connection to the south, reconfiguration of ramp geometry to achieve intended design speeds, and the addition of active mode facilities, all while maintaining the designed flows and grading to existing ponds.

The interchange design included a full detailed design of the ultimate interchange configuration to connect to future south connection with 128 Avenue NE, followed by scaling back the design to provide the necessary capacity and traffic movements to support only a north connection.  Changes included pre-grading width for future ramp widenings, relocating right turn ramp movements to reduce traffic speed, redirecting traffic to run northbound traffic on the future SB bridge deck, and configuring the traffic signal lighting to allow for a free flow ramp turning movement during the opening day configuration that can easily be changed to a standard signalized intersection when the south connection is constructed.  Utilities such as stormwater and streetlighting were also designed to accommodate the ultimate interchange configuration in terms of location, depth, and capacity or luminance respectively.

The extent of paving and concrete flatworks construction was also evaluated, leading to the full construction of some ultimate infrastructure to alleviate future constructability concerns and material waste. Similarly, areas of asphalt paving were identified that could be pre-graded and topsoiled for future construction, or areas where only gravel and a single lift of asphalt could be constructed to differ final asphalt paving until the need for the paved area arises.

The bridge design needed to balance a variety of competing priorities between constructability, expandability and costs.  Steel girders were ultimately chosen over concrete girders for the ease of future bridge widening.  Consideration was given to the placement of the barrier protection during the initial stage and where that construction joint would fall once the bridge was widened.