Method for in situ determination of concrete strength
AssigneeA/S Trondhjems Nagle & Spigerfabrik
InventorRandulf Inge Johansen
Life of this patent
Estimating the term…
Abstract
A method is provided for assessing the strength of a concrete structure by determining the flexural strength at a test section at the base of a concrete core projection established by disposing a tubular form element in the freshly poured and levelled concrete and removing the tubular form when the concrete has hardened sufficiently. A special load cell is inserted in the surface opening of the slit left in the concrete by the tubular form and the load cell activated to apply a recordable, gradually increasing force to the top of the core projection until rupture occurs at the base of the core projection. The flexural strength of the test section is then derived from recordings of the applied force at the moment of rupture.
Claims3
A method for in situ determination of concrete strength in a concrete structure or parts thereof, wherein the flexural strength of the concrete is determined at a test section located a certain distance from the surface of the concrete structure and preferably parallel thereto, said method comprising establishing the test section by arranging a tubular form element of a certain length in freshly poured and levelled concrete and extending down from the surface thereof, allowing the concrete to harden at least partly, removing the form element from the hardened or partly hardened concrete to leave in the concrete a slit surrounding a concrete core projection having a shape corresponding to the dimensions of the form element, and then subjecting the concrete core to a bending test by applying a recordable force at a place in the slit opening between the concrete core and the surrounding concrete until rupture occurs at the test section where the core is connected to the remainind concrete.
Dependencies are inferred from the claim text.