Support form for a grade beam or slab

摘要

A support form for use in the casting of a grade beam on piles comprises an elongate rectangular body having a width equal to the intended width of the grade beam. The body is located under the intended grade beam and the grade beam cast on top of the form. The form is manufactured from polystyrene foam which is cut to form interior voids extending longitudinally of the body. The body prevents soil from entering the area underneath the grade beam. The body is formed with side walls having a wedging action and a collapsible central support so that a top wall of the body can collapse onto the bottom of the body if the forces from the soil due to exansion exceed a predetermined maximum force thus preventing the soil from causing heaving of the grade beam after installation.