Title:
Tensile Cracking and Flexure-Shear Capacity of Recycled Aggregate Concrete (Prepublished)
Author(s):
Sourav Chakraborty and Kolluru V. L. Subramaniam
Publication:
Structural Journal
Volume:
Issue:
Appears on pages(s):
Keywords:
aggregate interlock; fracture; RCA; recycled aggregate concrete; shear capacity
DOI:
10.14359/51746815
Date:
5/14/2025
Abstract:
The reduction in the shear capacity using recycled coarse aggregate made from crushed concrete is evaluated in terms of tensile cracking and fracture surface characteristics. An experimental investigation is presented into the fracture and flexure-shear behaviors of recycled aggregate concrete (RAC). Replacing natural aggregate in concrete proportioned for 30 MPa compressive strength with recycled coarse aggregate results in lower compressive and tensile strengths. The tensile fracture surface characteristics vary between RAC and natural aggregate concrete (NAC). While the surface area created in the tensile fracture of RAC is larger than that of NAC, the fracture surface profile in RAC has a smaller roughness than that of NAC. In the flexure-shear response of reinforced concrete beams, the dilatancy determined from the slip and crack opening displacements measured across the shear crack is smaller in RAC than NAC. The failure in the reinforced beam is due to the frictional stress transfer loss across the primary shear crack. There is a larger decrease in the shear capacity with the use of RAC than indicated by the reduction in compressive strength. The reduced shear capacity of reinforced RAC is due to the combined influences of reduced tensile strength and crack surface roughness. The design provisions require calibration for crack surface roughness when using RAC in structural applications.