SHEAR STRENGTH CHARACTERISTICS OF THE INTERFACE BETWEEN POLYURETHANE FOAM AND CONCRETE BY DIRECT SHEAR BOX TESTS

Abstract

A method for renovating a deteriorated bridge as a lightweight embankment was proposed. However, it is possible that a polyurethane foam separate from sufface of bridge member due to the holizontal force by earthquake. In this research, a series of direct shear box tests were conducted to evaluate the adhesive strength of polyurethane foam. Therefore, the interface shear strength between polyurethane foam and concrete plate as well as shear strength of polyurethane foam were carried out. As a result, The polyurethane foam was compressed by the inside of upper shear box during shearing and peeled off from the concrete plate when shear displacement reached approximately 30mm. The shear strength of the interface between polyurethane foam and concrete was affected by normal stress.