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ShawSpan™ units are high quality, low maintenance precast structures which can be used in a variety of applications including bridges for larger brooks and streams. Each ShawSpanTM unit is a precast concrete rigid-portal frame, with the horizontal top member of the frame functioning as a deck supporting soil cover, roadway and traffic loads across the clear span, and the vertical legs retaining the side fill soils to provide the desired opening height or rise for the structure. Typically, each leg is founded on a concrete strip footing which may be precast or cast-in-place. The standard ShawSpan™ unit width is 1.2m, therefore a 12m road width would be accommodated by placing 10 units side by side. Shaw Precast Solutions produces ShawSpan™ units in a broad range of sizes from 4.27m to 15.33m clear spans (in 610mm increments), and clear rise from 1.22m to 3.05m (in 610mm increments). The maximum allowable span for a ShawSpan™ unit is primarily a function of soil cover (depth of soil over the deck) and the specified live load. Based on transportation restrictions, the maximum inside clear height is approximately 3.0m. Additional opening height can be provided by setting the ShawSpan units on a pony wall/footing assembly.
The structural design for each ShawSpan™ project is carried out by experienced Professional Engineers at Shaw Precast Solutions. The design and reinforcement for a typical unit are functions of the following:  Clear span: measured from the inside face of each leg
Clear rise: measured from bottom of the leg to underside of deck at midspan
Fill cover: The depth of soil over the deck
Specified Design Loads: For example CL625/CS700 truck live load.
Footing design is based on the parameters noted above and the site specific geotechnical conditions. Strip footings can be cast-in-place on site or precast at our plant with the ShawSpan™ units for delivery to the site. ShawSpansTM have been successfully installed on other foundation systems such as piles, and cantilevered retaining walls. Because of the nature of the rigid portal frame, and the interaction between frame and foundation, Shaw Precast Solutions recommends that there be close co-operation between the foundation designer and our design staff to ensure the design of both systems will be adequate to carry the specified loads on the frame, and in turn the loads transferred to the foundation by the frame.
 TYPICAL DEVELOPED ELEVATION |
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| DEVELOPED ELEVATION - PEDESTAL FOOTING |
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Shaw Precast Solutions will assist Consultants with layout, unit size, and installation issues on ShawSpan™ projects. Project specific CAD drawings for proposals and tenders can be developed upon request. Details for items to be cast into the ShawSpan™ units such as guardrail inserts, scupper drains or concrete curb connections should be discussed with our engineering staff prior to issue of project drawings, to ensure that these details are feasible. Our staff can also provide sketches for inclusion on project drawings.
| POSSIBLE CONFIGURATION FOR EXTENDED HEIGHT |
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