Qingyang Region Ready-mixed Concrete Strength Curve Of Resilience Method Research

Ready-mixed concrete has been replaced ordinary concrete as the main structural materia1in engineering practice.Because of the Simplicity and economy of operation,rebound method has become the most common form of nondestructive test method.Due to the various areas of concrete raw materials, molding process, different geographical climate conditions,the techni cal specification for concrete compressive strength of the rebound method (JGJ/T23-2011) su ggested to improve the accuracy of concrete rebound testing by establishing regional strength around the curve.This paper is based on the project of preparing the acceptance procedures about using re bound method to detect the ready-mixed concrete compressive strength in Qinghai,adopting t he representation of the raw materials in Qingyang,Through the15local bituminous concrete stations,with common mixture ratio, make a certain number of cube concrete specimen in the number of11strength grade and rated age from C10to C60,laboratory standard curing,block t he springback, compressive strength and modulus of elasticity test according to the age. Analy zed the affecting factors of affecting the ready-mixed concrete compressive strength by the re bound method,such as admixture, additive, etc. Analyzing the test data,concluding the tenden cy of the modulus of elasticity,work out the ready-mixed concrete strength curve of Qingyang,data error had to meet the requirements of the specification on the local strength curve,develo ped the acceptance procedures of using rebound method to detect Qingyang region ready-mix ed concrete compressive strength.In engineering practice, its strength estimate value superior t o the national unified curve.