construction management: concrete construction

Explore cement, fine aggregate, water, and air in concrete, and how mix trials and cement types meet project strength and durability. Learn how workability and curing influence concrete performance.

Explore the two main cement types: hydraulic cement, which hardens by hydration and strengthens underwater, and non-hydraulic cement, which relies on carbonation in dry environments.

Learn how concrete admixtures improve workability and durability by stabilizing the water–cement ratio, enhancing hydration, and reducing porosity, while using air-entraining and corrosion-inhibiting additives.

Explore how pozzolans and industrial byproducts like micro silica, silica fume, fly ash, and slag enhance concrete by increasing cohesion, strength, workability, and durability.

Balance the water-cement ratio to optimize workability without compromising strength or durability. Employ admixtures like water-reducing agents or superplasticizers and ensure proper mix design to reduce voids and improve performance.

Fiber reinforced concrete uses 1 to 2 percent fibers to boost toughness, crack resistance, and impact resistance, while not significantly increasing compressive strength and enhancing stiffness and elasticity.

Fills around reinforcement without vibration, delivering a dense, void-free concrete with a strong bond to reinforcement. Improve viscosity and stability with admixtures to prevent segregation.

Explore how cement, coarse and fine aggregates, water, and admixtures shape concrete properties, including compressive strength, tensile strength, workability, curing, and durability.

Explore reinforcement for concrete by examining land bars and wire fabric, and how they bond with concrete. Assess epoxy coated and stainless steel reinforcement for corrosion resistance in harsh environments.

Explore how concrete cracks arise from shrinkage, settlement, and expansion under temperature and moisture restraint. Learn to limit crack width and address differential settlement to prevent corrosion of reinforcing steel.

Manage cracks in concrete by controlling moisture evaporation, ensuring proper curing, and using contraction joints or steel reinforcement to keep cracks small and straight, and by design expansion joints.

Explore the concept of pre-stressed concrete, applying compressive forces to counteract bending tension, increase beam capacity, and reduce service cracks for longer concrete structure durability.

Explore prestressing steel for concrete: high-strength strands around 1860 units, rust-free and contamination-free, drawn and stress-relieved, with tests for diameter, yield, elongation, and breaking load.

Explore the principles of pre-tensioning and post-tensioning in concrete construction, including tendon installation, ducts, grouting, bonding versus unbonded systems, and transfer of stresses to concrete for strength.

Prestressed concrete enhances structural capacity and enables longer spans by reducing slab thickness and column sizes, reducing dead load and material use for bridges and buildings.

Examine the layout of prestressing steel, emphasizing eccentric prestress above the neutral axis to boost bridge strength, while accounting for losses and adjusting jacking force to stay within limits.