Stiffness of Flexurally Cracked Reinforced Concrete Pipe
Frank J. Heger and Atis A. Liepins
Appears on pages(s):
computer programs; concrete pipes; cracking (fracturing); d e f l e c tion;55-64.
finite element method; reinforced concrete pipes; stiffness.
Expressions are provided for the stiffness of reinforced concrete pipe that account for the state of flexural cracking in the pipe wall. The stiffness depends on the effective elastic constants of pipe materials and on the effective section properties of the flexurally cracked pipe wall. Effective section properties are determined by the pipe wall thickness, the ratio of cracking moment to the internal moment at the specific section on the pipe circumference, the bonding between steel and concrete as determined by the type and arrangement of reinforcement, and the amount of circumferentially disposed reinforcing steel. Coefficients in the expressions for wall stiffness are determined by correlating computed and measured deflections of a large number of pipe subjected to a three-edge bearing test. These stiffness expressions are incorporated into SPIDA a computer program for computing earth loads, earth pressure distributions, and reinforcement designs of buried concrete pipe.