Calculation of Actual Bar Spacing

Bar spacing at every station along the beam span is checked to make sure it is within the code limits.

For bottom bars the spacing is taken as:

S = \frac{b_{w} - 2 c_{c} - 2 d_{b (Transvers)} - d_{b (Longitudinal)}}{Total Number of Bars - 1}

Equation 5-5

For top bars the spacing is taken as:

S = \frac{b_{f} - 2 c_{c} - 2 d_{b (Transvers)} - d_{b (Longitudinal)}}{Total Number of Bars - 1}

Equation 5-6

where

b_f

min(b_eff, 0.1× Span Length)ACI-10.6.6

Note: The user is responsible for providing reinforcement in the remainder of the slab when beam spacing is larger than 0.1 x Span Length.

The clear side cover c_c and transverse reinforcement diameter d_b are considered in the above equations only if the section is rectangular (not for "T" or "L" sections). Additionally, if one shear bar leg is assigned, the value d_{b(transverse)} in the above equations is taken as zero.

RAM Concrete Beam considers only the "Concrete not exposed to weather or in contact with ground" condition specified in ACI 7.7.1. Thus,

For beams, c_c = 1.50in

For joists, c_c = 0.75 in (#11 and smaller)

c_c = 1.50 in (#14 and #18)

Note: In situations where the top reinforcement starts and ends in two spans with different effective flange widths, the spacing is always based on the smaller of the two flange widths.