Workability and Quality – Effects of “too wet” concrete If concrete is made overly wet (excess water beyond design water–cement ratio), which of the following undesirable effects can occur?

Introduction / Context:
Water is essential for hydration and workability, but too much water in a concrete mix degrades strength and durability. Field practices sometimes add water to increase slump quickly, but the side effects can be severe and long-lasting. Recognizing these effects encourages proper use of water reducers and better control of mix proportions.

Given Data / Assumptions:

• Nominal or designed concrete mixes with conventional materials.
• Excess mixing water above the designed water–cement ratio.
• Normal placing and curing conditions.

Concept / Approach:

Excess water increases capillary porosity after evaporation, which lowers compressive strength and modulus. It also promotes segregation, where heavier aggregates settle and paste rises, and bleeding, which can create laitance—weak, powdery layers at the surface. Overall, the hardened concrete becomes less dense and more permeable, compromising durability and bond with reinforcement. Therefore, all listed effects are typical consequences of overly wet concrete.

Step-by-Step Solution:

Verification / Alternative check:

Site QA data show reduced cube strengths and poor surface finish when extra water is added without mix design adjustments; admixtures are preferred to improve workability without raising w/c ratio.

Why Other Options Are Wrong:

Each individual effect is real, but selecting only one would ignore the broader set of consequences; “All” captures the full picture.

Common Pitfalls:

Allowing retempering with water, ignoring moisture in aggregates, and not accounting for temperature’s effect on slump, leading to poor control on site.

Final Answer:

All of the above