1. The problem statement, all variables and given/known data I have to design the formwork system for an octagonal bridge pier similar to the type shown below, plus a headstock. [PLAIN]http://img577.imageshack.us/img577/5743/prexconcretebridgecolum.jpg [Broken] 2. Relevant equations 3. The attempt at a solution I can use any system I want and I have gathered a number that I can choose from. But I really want to use a system like this one (for the pier): [PLAIN]http://img594.imageshack.us/img594/5471/placeconcretecolumnform.jpg [Broken] [PLAIN]http://img831.imageshack.us/img831/9784/cleaningcolumnformwork.jpg [Broken] but I am not certain how to design it to resist the concrete pressure. Does anyone know of any literature that deals with this kind of system in any way? How do you evaluate the hoop stress of an octagonal pressure vessel like the pier form or iregular shaped and sloping pressure vessel such as the pier cap form? Is the weight of concrete and formwork of the pier cap transferred through the pier form walls axially to the ground? With these two questions answered would I have enough information to pick a steel thickness and grade and also design a connection for the two halves?