Predicting Mechanical Properties of High Performance Concrete by using non-destructive tests

الملخص EN

In this study, high performance concrete mixes were produced by using high range water reducing agent and also by using 10% silica fume or 10% high reactivity metakaolin as a partial replacement by weight of cement.

Three cement contents (350, 450, and 550) kg/m3 were used through this study.

A total of 330 (100mm) cubes, 132 (100×200 mm) cylinders, 132 (100×100×400 mm) prisms, and 66 (150×300 mm) cylinders were casted and cured to the required age of test .

All specimens were cured in tap water except 165 cubes, which were submerged in Cl - + SO4-- solution at concentration identical to those present in severe aggressive environment to study the effect of this solution on the compressive strength of high performance concrete mixes.

Compressive strength, splitting tensile strength, modulus of rupture, static modulus, rebound number, ultrasonic pulse velocity, dynamic modulus, initial surface absorption, density, and total absorption tests were investigated for all mixes at 7, 28, 90, and 120 days age.

tensile strength, Results of the destructive tests (compressive strength, splitting modulus of rupture, and static modulus) and non–destructive tests (hammer, ultrasonic pulse velocity, and dynamic modulus) are statistically analyzed by using SPSS Ver.15 software to study the possibility of predicting the mechanical properties of high performance concrete by using non–destructive tests.

Simple and multiple linear regression analysis of the obtained results leads to the proposed statistical models for evaluating the compressive strength, splitting tensile strength, modulus of rupture, and static modulus by using one or two or three of the above mentioned non–destructive tests.

Analysis of variance (ANOVA) and t–test was also used to investigate the adequacy of the statistical models.