The concrete containing Type I cement in a structure is cured for 3 days at 36°F, followed by 2 days at 53°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.

Given that dead load = 55 psf, live load = 100 psf, roof live load = 40 psf, snow load = 40 psf, and wind load = 25 psf, determine the largest factored load.

The 7- and 28-day strengths are reduced by cold temperatures, although the long-term strength tends to be enhanced.

What is progressive collapse?

Damage or failure from fires is an example of a _______.

Excessive deflections for normal service is an example of a _______.

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 3,600 psi.

Subfreezing temperatures can significantly increase the compressive and tensile strengths and the modulus of elasticity of moist concrete.

The following two load combinations are used when dead loads stabilize the structure against overturning and sliding forces. U = 1.2D + 1.0WU = 1.2D + 1.0E

Strength reduction factors are _______ one.