Beam-Column Joint

Question 1

Describe the functions of horizontal transverse reinforcement in a joint

Answer 1

1. Shear capacity
   - hor. reinforcement enables formation of diagonal compression field and truss mechanism
   - it is this mechanism that transfers shear through the joint
2. confinement
   - confines core concrete
   - increases compression strength
   - keeps core together (stops inward buckling)
3. anti buckling

Question 2

How is the vertical shear force in the joint estimated and how is the provision of reinforcement for this shear dealt with

Answer 2

• vertical design shear can be approximated through rati between the height of the beam and column
  Vjv* = Vvh* hb/hc
• or determined through first princples like horizontal shear
• provided for through the column reinforcement that crosses the potential failure plane
• typically the intermediate columns along the long side of the column (short side cause the vertical joint shear and hence cannot contribute to resisting it)