/////////////////////////////////////////////////////////////\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\

logo

Dedication

Time

consistencY



σy
⇀τyx


σx←τxy



Reinforced Concrete




Reinforced Concrete is a composite material that combines the usage of both concrete and steel where the steel reinforcement is used to counteract the lack of tensile strength in concrete.


Concrete is a mixture of fine and coarse aggregates that are held together by a cement paste (cement mixed with water) that hardens over time.


Pros and Cons of Reinforced Concrete

    Pros:

  • Has good tensile strength compared to plain concrete
  • Is shapeless like water, it can be made into any kind of shape
  • Strength increases with age
  • Is fire resistant
  • Is a better material for a strong foundation because of its heaviness in weight, which is the reason why most building have a reinforced concrete foundation
  • Needs less skilled labor compared to steel

    Cons:

  • Is more expensive than structural steel
  • Is a heavy material, therefore, it cannot span long distance like steel
  • Takes more time in construction compared to steel
  • Is not recyclable for the construction of a new structure (has nil scrap value)
  • Not a good material for seismic prone areas

  1. Rebar Table
  2. Rebar size table
    Figure 1: Rebar Information Table (ASTM)

  3. Relationship between Shear (V) and Moment (M) diagrams and steel reinforcements in a simply supported and cantilever beam.
  4. Relationship between Shear (V) and Moment (M) diagrams and steel reinforcements in a simply supported beam Relationship between Shear (V) and Moment (M) diagrams and steel reinforcements in a cantilever beam
    Figure 2: Relationship between Shear (V) and Moment (M) diagrams and steel reinforcements in a simply supported and cantilever beam

    Worked out problems with solutions in pdf files

    Cracks in an Unreinforced Beam


    Draw the cracks in an unreinforced concrete simply supported beam subjected to a uniform distributed load acting downwards. (transverse and longitudinal)

    SimplySupportedBeamConcreteCrackssolution.pdf


    Ultimate Moment Capacity for a Singly Reinforced Beam


    Find the ultimate moment capacity (Φ Mn) for the singly reinforced rectangular beam shown below.

    Singly Reinforced Beam Analysis Ex1
    Figure 3: Singly reinforced concrete beam analysis example 1 (Beam)

    SinglyReinforcedEx1solution.pdf

    Find the ultimate moment capacity (Φ Mn) for the singly reinforced rectangular beam shown below.

    Singly Reinforced Beam Analysis Ex2
    Figure 4: Singly reinforced concrete beam analysis example 2 (Beam)

    SinglyReinforcedEx2solution.pdf

    Find the required height, h, of the reinforced concrete cross section for the simply supported beam with a uniform live and dead load (self-weight included) as shown below, assuming that the steel has yielded (use factored loads).

    Simply supported beam with a singly reinforced concrete beam cross section
    Figure 5: Simply supported beam with a singly reinforced concrete cross section

    ReinforcedConcreteEx4solution.pdf

    Find the uniformly distributed live load, wL, of the reinforced concrete cross section for the simply supported beam with a uniform live and dead load (self-weight is not included) as shown below, assuming that the steel has yielded (use factored loads). The unit weight of the reinforced concrete section, ϒconc is 150 pcf.

    Simply supported beam with a singly reinforced concrete beam cross section
    Figure 6: Simply supported beam with a singly reinforced concrete cross section

    ReinforcedConcreteEx6solution.pdf


    Ultimate Load for a Column


    Find the ultimate load (ΦPn) for the short tied column as shown below.

    Short tied reinforced concrete column
    Figure 7: Short tied reinforced concrete column example

    ReinforcedConcreteEx5solution.pdf


    Under-reinforced or Over-reinforced


    For the singly reinforced concrete beam as shown below, check if beam is under-reinforced or over-reinforced.

    Simply supported beam with a singly reinforced concrete beam cross section
    Figure 8: Singly reinforced concrete beam

    ReinforcedConcreteEx7solution.pdf


    Ultimate Moment Capacity for a Doubly Reinforced Beam


    Find the ultimate moment capacity (Φ Mn) for the doubly reinforced concrete rectangular beam shown below.

    Doubly Reinforced Beam Analysis Ex1
    Figure 9: Doubly Reinforced Beam Analysis Ex1 (Beam)

    ReinforcedConcreteEx8solution.pdf


    Ultimate Moment Capacity for a T-beam With Two Rows of Steel in Tension


    Find the ultimate moment capacity (Φ Mn) for the reinforced concrete T beam with 2 rows of steel as shown below.

    Reinforced T Beam Analysis with 2 rows of steel
    Figure 10: Reinforced T Beam Analysis with 2 rows of steel (Ex1)

    ReinforcedConcreteEx9(Tbeam)solution.pdf

    Figure :

    solution.pdf


    Shear Reinforcement Analysis and Design


    Find the ultimate shear capacity (Φ Vn) for the singly reinforced rectangular beam shown below.

    Singly Reinforced Beam Analysis Ex3
    Figure 11: Singly reinforced concrete beam analysis example 3 (Beam)

    SinglyReinforcedEx3solution.pdf

    Design the shear reinforcement (stirrups) for this 24 ft span simply supported reinforced concrete beam as shown below. Self-weight of the beam is not included in the dead load, ϒconc = 150 pcf.
    (a)Find Vu @ d,
    (b)Find the ultimate shear strength provided by concrete (Φ Vc) from cross section,
    (c)Find (Φ Vc)/2 from cross section,
    (d)Are stirrups required?

    shear reinforcement problem
    Figure 12: Simply supported reinforced concrete beam (shear reinforcement problem)

    ShearReinforcementEx2solution.pdf

    Design the shear reinforcement (stirrups) for this 28 ft span simply supported reinforced concrete beam as shown below. Self-weight of the beam is not included in the dead load, ϒconc = 150 pcf.

    shear reinforcement design problem
    Figure 13: Simply supported reinforced concrete beam (shear reinforcement design problem)

    ReinforcedConcreteEx12solution.pdf

    Reinforced Concrete Beam Design (Flexural and Shear)


    Design this 28 ft span cantilever beam as shown below, using #3 stirrups. Self-weight of the beam is not included in the dead load, ϒconc = 150 pcf.

    Cantilever beam reinforced concrete design
    Figure 14: Cantilever beam reinforced concrete design

    ReinforcedConcreteEx11solution.pdf


  5. Analysis of doubly reinforced beam
  6. Shear reinforcement example

    Videos










↾τxy→σx

↽τyx
↓σy



w(x)
↧↧↧↧↧↧↧↧↧↧↧↧↧↧↧↧↧↧↧↧↧↧↧↧↧↧↧↧↧↧↧↧↧↧↧↧↧↧↧↧↧




FOLLOW US ON

                         
                    
Questions about this website? Contact our Webmaster .

Copyright © 2018 DTY Tutoring, Inc. All rights reserved . Addis Ababa, Ethiopia.



/////////////////////////////////////////////////////////////\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\