A Reevaulation of Test Data on Development Length and Splices
C. O. Orangun, J. O. Jirsa, and J. E. Breen
Appears on pages(s):
anchorage (structural); beams (supports); bond (concrete to reinforcement); cover;deformed reinforcement; failure: lap connections; regression analysis; reinforced concrete;reinforcing steels; splicing;stress transfer;structural engineering.
An equation is developed for calculating development and splice lengths for deformed bars. The equation is based on a nonlinear regression analysis of test results of beams with lap splices and reflects the effect of length, cover, spacing, bar diameter, concrete strength, and transverse reinforcement on the strength of anchored bars. Design recommendations are proposed and compared with current provisions for development splice length. The comparison shows that for the minimum cover and spacing (no transverse reinforcement) the proposed provisions require increases in anchorage lengths of IO to 25 percent over current provisions. If cover is increased or transverse reinforcement is added, the splice length for large bars may be reduced by as much as 60 percent over that required by present provisions.