Basic Research On The Rebound Curve Of High Strength Concrete In Guangzhou Area

In recent years,the application of high strength concrete is more and more extensive in civil engineering of our country.In order to promote the application of new technology of high strength concrete,solve the practical problems of strength testing of high strength concrete in engineering application and grasp the detection aaccuracy of the high strength concrete national strength curve in the local area,it is necessary to combine with the actual situation of local area,to carry out the testing technology research of high strength concrete rebound method before developed local testing standards of high strength concrete in our province.In this paper,the commodity concrete which were produced in Guangzhou are used as specimen,and the national curve of rebound method for testing high strength concrete has been validated.At the same time,comparative test has been taken on detection precision of high strength concrete rebound instrument between two different types.The main contents of this paper include:(1)A representative commercial concrete production enterprise has been selected in Guangzhou area,the general raw materials of Guangzhou area are used to made of the concrete specimen,and the rebound values of test specimen has been test by use of 4.5J high strength rebound instrument and 5.5J high strength rebound instrument.The press has been used on compressive strength test of specimens as well.(2)A representative mathematical model are selected and established for corresponding testing strength curve of high strength concrete between 4.5J high strength rebound instrument and 5.5J high strength rebound instrument.The accuracy and reliability analysis between two kinds of testing strength curve in high strength concrete rebound instrument and the corresponding applicable conditions are carried out.And compared with national testing strength curve of the high strength concrete,the national curve applicability for Guangzhou area has been verified.(3)The best fitting high strength concrete test curve is chose to verified that the curve is applicable to other concrete mixing station of Guangzhou,which shows that the test curve has a certain reference value in the area of Guangzhou,providing data support for the establishment of the curve in Guangzhou city and the area of Guangdong province.(4)The testing accuracy of 4.5J high strength rebound instrument and 5.5J high strength rebound instrument is compared to analyze the respective advantages and application conditions,providing a high strength rebound instrument selection application reference for researching and developing the high strength concrete curve in local area.This paper presents the results of verification on which 4.5J high strength rebound tester and 5.5J high strength resiliometer corresponding to high strength concrete national curve app lied on the concrete production enterprises,and also presents the corresponding test curve.Th e basic research results can be used as fundamental results for high strength concrete testing st rength curve in Guangdong province(Guangzhou city).