Cracking of concrete cover along anchored deformed reinforcing bars

Abstract

Synopsis The state of stress in the concrete due to bond forces from deformed reinforcing bars is analysed. For determination of the cracking resistance of the concrete cover, a concrete ring model is used. The stresses are calculated for an elastic stage, a plastic stage, and an elastic stage with internal ring cracks. The appearance of the concrete cover cracks along the deformed bars in the bond zones for normal cover thickness can be determined by using the mean of the values obtained for the two last stages. The partly cracked elastic stage gives cracking loads just on the safe side.

Bond Deterioration of Reinforcing Steel in Concrete Due to Corrosion

“…Tepfers considered that the deviation from the elastic theory is due to the fact that there is sorne plastic deformation at the steel-concrete interface. For normal-strength concrete, use of the elastic assumption (equation (3.1» is found to be the more appropriate (Tepfers 1979). If the c/d b vaIue is high, failure occurs by shearing of the concrete between the ribs.…”

A Reassessment of the Analysis Provisions for Bond and Anchorage Length of Deformed Reinforcing Bars in Tension

“…Figure 7 is a plot of the normalized bond strength (f ub /(f ' c ) 0.5 ) against the dimensionless parameter c/db for the test specimens together with points obtained from Tepfers' analytical solution using (3). The wide deviations of the experimental results from Tepfers' assumed linear behavior, particularly at higher values of bond stress, indicates that the assumption of fully elastic behavior of the concrete zone outside the assumed thick cylinder zone is not entirely valid.…”

“…By applying the thick cylinder theory, Tepfers [2,3,4] derived a relationship between radial splitting forces at failure and f ' t . The radial stress, σ r was regarded as the pressure acting against the thick walled cylinder while the inner diameter of the cylinder was considered as the reinforcing bar diameter.…”

Influence of Lap Splices on the Deformation Capacity of RC Walls. I: Database Assembly, Recent Experimental Data, and Findings for Model Development

“…The resultant bond force can be decomposed into a component parallel to the rebar axis and a radial one. The former causes shearing of the concrete between the rebar ribs, whereas the latter radial forces induce tensile stresses in the surrounding concrete (Tepfers 1979). These two components can be directly related with the two types of bond failures that are usually considered, namely pull-out-also described as "crushing and sleeving" (Priestley et al 1996)-and splitting.…”