How can both high compressive and tensile strength be achieved in concrete?

Reinforcing concrete is the most effective method for achieving both high compressive and tensile strength. Concrete is inherently strong in compression but weak in tension. When concrete is reinforced, typically with materials such as steel rebar, the tensile strength of the composite structure is significantly enhanced. This reinforcement allows the concrete to withstand pulling forces and enhances its overall durability.

The interplay between the concrete and the reinforcement means that when stresses occur, the reinforcement takes on the tensile forces, preventing cracking and increasing the overall strength of the concrete structure. This method is fundamental in construction, ensuring that structures can safely bear loads and resist various forces.

Other options, such as using only water-reducing agents, applying heat during curing, or reducing the water-to-cement ratio, can contribute to improving specific characteristics of concrete but do not effectively address the challenge of achieving high tensile strength, which is critical for structural integrity. Water-reducing agents primarily help with workability, heat application during curing can speed up curing processes but does not inherently enhance tensile strength, and reducing water-to-cement ratio can improve compressive strength but may not impact tensile strength without the reinforcement solution in place.