Concrete technology: proper proportioning of concrete ingredients ensures which of the following desirable properties in construction practice?

Introduction / Context:
Proportioning concrete means selecting the right ratio of cement, aggregates, water, and admixtures to meet specific performance requirements. This step directly affects the concrete’s quality in terms of strength, durability, and impermeability.

Given Data / Assumptions:

• Concrete mix includes cement, sand, coarse aggregates, water, and optionally admixtures.
• Performance metrics: strength, workability, durability, impermeability.
• Proper proportioning per IS codes or ACI mix design methods is assumed.

Concept / Approach:
Correct proportioning ensures enough paste to coat aggregates, maintain workability, and provide a dense matrix. Balanced water–cement ratio ensures strength and reduces permeability. Adequate cement and proper grading of aggregates enhance durability and water resistance.

Step-by-Step Solution:
Identify target properties: compressive strength, slump/workability, resistance to shrinkage and cracking.Relate each property to mix design: W/C ratio → strength/durability; grading → workability; low permeability → water resistance.Conclude that all listed properties are achieved through proper proportioning.

Verification / Alternative check:
Standards such as IS 10262 (India) and ACI 211 confirm that proportioning aims simultaneously at strength, durability, and workability.

Why Other Options Are Wrong:

• Choosing only strength/workability ignores durability and impermeability.
• Focusing only on water tightness or resistance misses the holistic design goals.

Common Pitfalls:

• Overemphasis on strength without considering workability or durability, leading to cracks and permeability issues.

Final Answer:
all the above