Lecture 1 Reinforce Concrete Floor and Roof Systems
- 1. Reinforce Concrete Floor and Roof Systems Engr. M. Anisuzzaman Khan Assistant Professor, CE
- 2. Objective The goal of today’s lecture is • to provide an in-depth understanding of reinforced concrete (RC) floor and roof systems • their design considerations, and practical applications in modern civil engineering. • By the end of this lecture, you should be able to identify the various types of RC floor and roof systems, understand the factors influencing their design, and apply that knowledge in real-world projects.
- 3. Reinforced Concrete Floor and Roof • providing support and resistance to various loads • are responsible for carrying loads from both permanent (dead) and transient (live) , such as furniture, occupants, and environmental forces like wind or seismic events.
- 4. Primary Functions • Provide a stable, load-bearing surface. • Transfer loads to vertical structural elements like columns and walls. • Offer safety, aesthetic appeal, and flexibility in design.
- 6. Types of Reinforced Concrete Floor Systems • Reinforced concrete floor systems can be categorized based on their design, functionality, and method of construction.
- 7. a. Slab Floor Systems • Solid Slab: A single, continuous reinforced concrete slab directly supported by beams or walls. Used for simple structures with short spans. • Applications: Low-rise buildings and residential structures. • Design Considerations: Thickness of slab, type of reinforcement (both top and bottom), deflection limits
- 8. b. Beam-Slab Systems • A concrete slab supported by beams, where the slab carries loads through bending, while the beams provide support and transfer the loads to columns. Applications: Common in medium to high-rise buildings. Design Considerations: • Size and spacing of beams. • Proper distribution of reinforcement in beams and slabs. • Deflection control.
- 9. c. Flat Slab System • A flat slab is a thick concrete slab without beams, supported directly by columns. It is commonly used for buildings with fewer load- bearing elements and where simplicity in design is needed. Applications: Parking structures, high-rise buildings, and modern commercial structures. Design Considerations: • Punching shear near the column connections. • Reinforcement placement (top and bottom). • Effective load transfer from slab to columns.
- 10. d. Ribbed Slab (Waffle Slab) • A slab with a grid of ribs or beams running in two directions, creating a waffle-like structure. The ribs reduce the amount of concrete used while still supporting large spans. Applications: Large-span buildings such as auditoriums, conference halls, and warehouses. Design Considerations: • Reinforcement layout in ribs. • Load distribution through ribs and slab. • Depth of ribs to prevent excessive deflection.
- 11. e. Hollow-Core Slab System • Precast reinforced concrete slabs that contain hollow cores to reduce weight while maintaining strength. Typically used in floors of multi-story buildings. Applications: Multi-story buildings, parking garages, and residential buildings. Design Considerations: • Precast manufacturing and transportation. • Spacing and connection between units. • Integration with other structural systems (e.g., beams).
- 20. Thank You