Effect of aggregate size on the tensile strength of hydraulic-concrete specimens

Conclusions

• 1. It is established that the ultimate tensile strength of concrete as determined by the splitting of cylinders, and also the ultimate axial compressive and tensile strengths, increase with increasing size of the concrete specimens.

• 2. The effect of the scale factor in concrete makes itself felt to a greater degree in tension than in compression.

• 3. On increasing the diameter of a specimen subject to splitting, R_st of the concrete decreases markedly at the outset (up to 41%). When R_st reaches 800–900 cm², the tensile strength of the concrete (Grade 300–500) stabilizes and approaches a constant value R_st= 1.9–2.1 MPa.

• 4. The influence exerted by the length of the test cylinder on the splitting-tensile strength of concrete is negligible, and may be disregarded in practice.

• 5. Equation (3) should be used to establish the in-place tensile strength of concrete from test data on its control specimens with consideration of aggregate coarseness.