Counterspan

About

Counterspan is a single-screen truss load explorer. It shows one sample bridge truss, with eight joints and thirteen members, and lets you see how a load you choose is shared across its members. WHAT YOU CAN DO - Move the load slider from 5 to 60 tonnes and watch the readouts update. - See the truss drawn with its supports, deck and members. Members are colored by utilization, or you can switch the coloring off to see the plain structure. - Read the status (HOLDS or OVERLOAD) and the peak member utilization. With the built-in sample truss every load in the slider's range holds, at about 1 percent peak utilization. - Compare three readouts: the number of triangles in the truss, the material used, and an efficiency figure (load carried per unit of material). - Open the member inspector for a list of every member, sorted by utilization, with its length and axial load. - Reset the load to its starting value at any time. The sample truss is fixed. You cannot add, move or remove joints or members, and there is no campaign, level or score. PRIVATE AND OFFLINE - Works offline on iPhone and iPad. - No ads, subscriptions, in-app purchases, accounts, analytics or tracking. Counterspan uses a simplified teaching model. It is not an engineering tool and must not be used to design or check real structures.