Question

Abrams established a rule that relates the water-cement ratio to strength of concrete. List two additional factors that have a significant influnce on the concrete strength.

Q2. Explain does why: • The transtion zone impact more rich cementitious mixtures than lean ones.

• Air entrainment reduce the strength of moderate to high strength concrete yet may enhance the strength of low strength concrete.

• ASTM cements Type I. III, and V have different impact on early and later strength of concretes made with these cements.

• On the basis of qual workability the surface characteristics of aggregate have a limited impact on the ultimate strength of concrete.

• the surface characteristics of aggregate have a clear impact on ultimate strength of concrete on the basis of qual water content.

• The cylinder strength is higher than that of cube's.

• The aspect ratio of concrete cylinders has no impact on compressive strength obtained in compression testing machine with brush platens.

• Concrete bridges should not be subjected to stress levels higher than 0.55 of ultimate strengths.

• the maximum aggregate size of aggregate have two opposing effects on concrete strength.

Answer 1