| With the great development of engineering construction, the domestic facing how to test and evaluate the scientific the new, reconstruction and reinforcement project has become an important problem urgently to be solved in construction industry. Now the Non-Destructive Testing technology of concrete in the field of various performance indicators for direct detection of concrete, concrete scientific and reasonable identification, evaluation, and gradually become the main means of detection and methods of attention by more and more countries and regions. But currently used the Non-Destructive Testing have some limitations: Some is simple operation, less process, but test accuracy is not high, big error; Some is high precision, but the operating procedures cumbersome, high testing costs, long cycle. Therefore, the Non-Destructive Testing industry try to explore a new technology direction with advantages of easy operation, high precision, less process, energy saving and environmental protection ect.This paper using the shear-resistance method and in-situ single-shearing method on which the two new types of technology to study and evaluation the relationship between shear strength and compressive strength of the concrete with drilling of small core samples. Comparison of laboratory tests and verification tests to explore the relevance and concrete relationship between shear strength and compressive strength, then making curve projections based on measured shear strength and compressive strength, and using these two new detection technology to evaluate the shear strength and compressive strength of concrete in Lanzhou area in the relation between the expression.This paper mainly for the following research:research concrete shear strength and compressive strength of the association in which strength grade is commonly used in lanzhou C15, C20, C30, C40, C50and C60; Establish method of shear strength curve and in-situ single-shearing strength curve of single shear method, fitting and error analysis curve are proposed indicator; At the same time comparative rebound method and ultrasonic-rebound comprehensive method, on the basis of the results of error analysis of each method and correlation coefficient to evaluate the advantages and disadvantages of each method; For conduct the shear-resistance method and in-situ single-shearing method engineering verification test, study the applicability of these two new methods; Moreover, the impact of different factors of shear-resistance method and in-situ single-shearing method are analysised and studied, then the integrated evaluate the two kinds of new methods.The results show that:the shear strength had a good correlation with the concrete compressive strength, both are basically the same trend; The shear-resistance method and in-situ single-shearing method through the shear strength are fitting curve test respectively in accordance with the actual compressive strength of concrete relative degree is high, the average relative error and the relative standard deviation is small, the high correlation coefficient and accuracy, curves fitting effect is better; By comparing the different detection methods, the shear-resistance method and in-situ single-shearing method has the obvious superiority, the fitting formula is accurate, simple; preliminary effect on aggregate size, the test surface, core length, diameter and other factors of the shear-resistance method and the in-situ single-shearing method are studied and analysis.Examples of verification by the project shows that:the shear-resistance method and in-situ single-shearing method is simple, little human impact, only slight structural damage, can be used in a complex environment conditions, etc., the correlation coefficient analysis of concrete between the use of a linear function of shear strength and compressive strength is more intuitive, easy to use, and the relative standard deviation and the mean relative error is smaller, more accurate test results. |
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