Joints Horizontal Hoops Area (Eurocodes)

According to EN 1998-1:2004, adequate confinement of the joint should be provided, to limit the maximum diagonal tensile stress of concrete. This requirement may be satisfied by providing horizontal hoops calculated from the following expression:

Where A_sh is the total area of the horizontal hoops and f_ctb is the design value of the tensile strength of concrete. For the definition of the other values users may refer to section 5.5.3.3(3) of EN 1998-1:2004.

Alternatively, the integrity of the joint after diagonal cracking may be ensured by horizontal hoop reinforcement. The total area of horizontal hoops that should be provided in the joint is calculated from the following equations:

For interior beam-column joints:

For exterior beam-column joints:

Where γ_Rd is equal to 1,2; for the definition of the other values users may refer to section 5.5.3.3(4) of EN 1998-1.