Designing post-tensioning traditionally has been a highly iterative and time-consuming process. There are virtually an infinite number of valid post-tensioning designs for a given concrete floor system. Variations can consist of different numbers of strands, in potentially different locations (layouts), and with different amounts of drape. Each solution requires a different amount of rebar and punching shear reinforcement.

The traditional design approach for engineers has been to define a post-tensioning solution that satisfies the minimum precompression and maximum spacing requirements in the system and then add strands until the flexural tension stress limits are satisfied. For codes that do not use flexural tensile stress limits the number of potential solutions is even larger as a wide array of post-tensioning, rebar, and punching shear combinations could be employed. Drapes are often determined using a load balancing approach, where the drapes are set to “balance” a predetermined fraction of the gravity loads. After the strand quantity and drapes have been determined, the corresponding supplemental rebar and punching shear reinforcement are calculated.

Because the traditional process can be tedious and time consuming, engineers typically do not investigate many design alternatives (normally only 1 or 2). As such, it is difficult to know how economical the final design is (total cost of materials and labor for concrete, post-tensioning, rebar, and punching shear reinforcement).

The post-tensioning optimization feature in RAM Concept uses intelligent search algorithms to compare thousands of design alternatives. This allows engineers to easily review and compare many different solutions side by side and select the best design for the situation. For a given strand layout, the post-tensioning optimization feature automatically weeds out invalid trials that do not satisfy required code criteria, which eliminates the need for manual iteration and saves hours of engineering time.