Comparative Study On Field Testing Methods For High Performance Concrete Compressive Strength

As a new type of cement-based material,high-performance concrete has the characteristics of high durability,high strength and strong corrosion resistance,and is widely used in large-scale engineering projects and reinforcement projects.With the application and development of high-performance concrete,how to effectively carry out on-site inspection of its strength has become the focus of relevant departments.The most common method to determine the compressive strength of concrete structures is to reserve cube test blocks,if the test blocks are not complete or there are doubts about the strength of high-performance concrete structures that have been constructed,it is impossible to make cube test blocks.It is also pointed out in the relevant quality acceptance criteria that it is necessary to perfect the test method,that is,to find a reliable,accurate,convenient and economical method for the high Performance concrete is tested on site to provide data basis for engineering quality acceptance.In this paper,the high-performance concrete specimens of C60,C70,C80,C90 and C100 are firstly subjected to the rebound method,the ultrasonic rebound combined method,cast-in-place pullout method,the post-install pullout method and the drilled core method.Test test and cubic compressive strength test,the selection of test materials and test operation methods were described in detail,and the applicability of five test methods in high-performance concrete strength test was verified.According to the test data of five kinds of detection methods,the strength analysis formulas for detecting the strength of high-performance concrete by different detection methods are obtained.The error analysis is carried out by statistical methods.The results show that the correlation and accuracy are ideal,which is suitable for testing on-site inspection of high performance concrete.Secondly,on the basis of the experiment,consider combining the two methods of rebound method and post-loading method to learn from each other and propose a new detection method–the rebound-pullout combined method,establish a correlation equation for the rebound value-post install force-concrete strength,and using double indicators to estimate the strength of high performance concrete.The mathematical formulas of linear,binomial and power functions are established.Through the comparison of index coefficients,the linear model is more accurate and easy to use.Compared with the single detection method,the method can estimate the structure more accurately.Finally,based on the project management theory and the basic theory of AHP,based on the current regulations and standards,the evaluation structure model of high performance concrete on-site inspection scheme is established.To avoid the influence of human factors and subjective evaluation,the entropy weight is used.The method assigns weights to the structural model and establishes a rating standard for high performance concrete on-site inspection programs.This paper is concerned with a variety of disciplines,comprehensive,providing a test basis for high-performance concrete strength-related on-site testing technical standards,and provides a reference for the evaluation of high-performance concrete strength field testing program.