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A concrete block will eventually break if a constant load is applied at 75% to 80% of its ultimate compressive strength due to _______.

The concrete in the core of a spiral column is subjected to a uniform confining stress σ3 of 220 psi. What will the compressive strength σ1 be? The unconfined uniaxial compressive strength is 4,700 psi.

The increase in the volume of concrete during hardening and drying under constant temperature is called shrinkage.

Other strength parameters are expressed relative to the compressive strength.

Concrete near the top of deep members tends to be weaker than the concrete lower down.

A well-graded aggregate mix helps reduce the shrinkage in a concrete structure.

Increasing the water/cement ratio of concrete might make it _______ but also _______.

A group of 30 tests on a given type of concrete had a mean strength of 4,200 psi and a standard deviation of 500 psi. Does this concrete satisfy the strength requirement for 3,000 psi concrete?

For _______ to occur, there must be a source of oxygen and moisture, both of which diffuse through the concrete.

At very slow loading rates, the strength of concrete decreases.