Thixotropic concrete forming system

摘要

The present invention discloses a method and a forming system that reduces the hydrostatic pressure caused by casting freshly mixed concrete or other cementicious material into a vertical form. Reducing the hydrostatic pressure in forms enables relatively weak materials to be used as forms and minimizes the amount of bracing necessary to support the forms—both of which lead to lower construction costs. The method uses the highly thixotropic properties of no-slump or low-slump concrete which enable the concrete to be quickly changed from a semi-solid state to a liquid state and back to a semi-solid state numerous times before it hardens and without affecting the concrete's quality. Since hydrostatic pressure is only present when a liquid state exists, minimizing the amount of liquid concrete in vertical forms will also minimize the hydrostatic pressure present.

主权项

1. A method of reducing the hydrostatic pressure created in a form when placing freshly mixed, highly thixotropic no slump concrete in the form, the method comprising:
a. erecting form boards to partially construct a vertical form having two or more spaced apart sides to form a cavity into which a monolithic concrete structure is to be cast in place in lifts and at least one said side erected in levels with a first level less than the height of said monolithic concrete structure and at least one subsequent level erected after one or more said lifts of concrete is cast into said cavity, b. casting one or more said lifts of no slump concrete into said cavity and each said lift is less than the height of said monolithic concrete structure and not higher than 48 inches and said no slump concrete is in a semi solid state that exerts little or no said hydrostatic pressure on said vertical form, c. vibrating a limited amount of said no slump concrete at any one time in a manner that limits the amounts of liquefied concrete and resultant hydrostatic pressure in said vertical form which causes said no slump concrete to be liquefied, visually consolidated, integrated into adjacent concrete and fill the immediate area of said cavity, d. ending said vibration to allow said no slump concrete to revert to its said semi solid state, e. repeating one or more above steps a through d until said vertical form is fully erected and a full height of said monolithic concrete structure is cast in place, whereby the amount of hydrostatic pressure present in said vertical form is reduced by said no slump concrete being contained in said semi solid state in said form and by limiting the amount of said no slump concrete being liquefied at any one time.