Principles and Practice of Engineering (PE) Civil: Structural Practice Exam

The water-cement ratio is a critical factor that influences the properties of concrete, particularly its compressive strength. The compressive strength of concrete is the capacity of the material to withstand axial loads without failure, which is primarily a function of the amount of cement in relation to the water present in the mix.

A lower water-cement ratio generally leads to higher compressive strength because it reduces the porosity of the hardened concrete, resulting in a denser material structure. This denser structure enhances the ability of the concrete to bear loads, thus increasing its strength. Conversely, if too much water is added, the excess can create voids in the concrete when the water evaporates, leading to reduced strength and durability.

While durability, workability, and resistance to freezing are also influenced by the water-cement ratio, it is compressive strength that is most directly affected. Durability is related but can be influenced by other factors like aggregate quality and environmental conditions. Workability is affected by the amount of water, but it is more about ease of mixing and placing rather than structural integrity. Resistance to freezing typically relates to the air content in the concrete rather than the specific water-cement ratio directly.

Thus, the water-cement ratio is fundamental