Fundamentals of Reinforced Concrete

Study Notes

Concrete is formed by mixing sand, gravel, crushed rock, or aggregates with a paste of cement and water to create a solid mass.
It is commonly used in construction due to its durability and versatility.

Incorporates reinforcing bars (rebar) to manage tension forces, crucial for maintaining moment equilibrium after cracking occurs.
Design requires adherence to static laws and material mechanics to assure constructability, cost-effectiveness, and longevity.

Economical and effective for both structural integrity and architectural aesthetics.
Offers fire resistance, enhancing safety during fires.
Provides rigidity for improved structural performance.
Low maintenance requirements reduce long-term costs.
Materials are widely available, making reinforced concrete a common building choice.

Exhibits low tensile strength, necessitating the use of reinforcement.
Requires forms and shoring to ensure structural stability during curing and setting.
Has relatively low strength per unit weight/volume when compared to other materials.
Experiences time-dependent volume changes, such as shrinkage, which can lead to structural concerns.

Compressive Strength: Ranges from 3000 to 20000 psi, indicating its ability to withstand axial loads.
Modulus of Elasticity: Lacks a specific value, depending on various factors including concrete composition.
Poisson's Ratio: Usually ranges from 0.11 to 0.21, with an average around 0.16; indicates the ratio of lateral strain to axial strain.
Shrinkage: Refers to volume decrease during hardening and drying under constant temperature.
Creep: Describes deformation under sustained load, impacting long-term structural integrity.
Tensile Strength: Assessed by applying compressive load on a lateral cylinder, important for understanding failure modes.
Shear Strength: Represents resistance to sliding forces, critical for structural stability.

Water/Cement Ratio: The relationship between the weight of water and cement affects the strength and durability of concrete.
Type of Cement: Different cement types impart varying properties to the final concrete product.
Supplementary Cementitious Materials: Addition of materials like fly ash or slag can enhance performance and sustainability.