Concrete is a mixture of water, cement, aggregate, and ______.

Creep tends to occur more in concrete mixtures with high _______ content.

Concrete subjected to a sustained axial load greater than the critical load will eventually fail under that load. The critical stress is _______ fc’.

The density of plain concrete is often assumed to be _____ lb/ft3.

_______, commonly found in soils in the western US, can cause concrete to break down due to chemical attack.

A longer yield plateau signifies a _______ ductile material.

Concrete strength increases with age.

Strength of concrete in a structure tends to be somewhat higher than the strength of the control cylinders made from the same concrete.

The concrete in the core of a spiral column is subjected to a uniform confining stress σ3 of 300 psi. What will the compressive strength σ1 be? The unconfined uniaxial compressive strength is 4,600 psi.

The concrete containing Type I cement in a structure is cured for 5 days at 43°F, followed by 2 days at 56°F. Use the maturity concept to estimate its strength as a percentage of the 28-day strength under standard curing. Maturity is defined as M = Σ(Ti + 50)(ti) where Ti is in degrees F and ti is in days.