Title: Shear Friction in High-Strength Concrete

Author(s): J. Walraven and J. Stroband

Publication: Symposium Paper

Volume: 149

Issue:

Appears on pages(s): 311-330

Keywords: aggregate interlock; cracking (fracturing); friction; high-strength concretes; shear properties; tension; Materials Research

DOI: 10.14359/4089

Date: 10/1/1994

Abstract:
The shear friction analogy is a valuable and simple tool that can be used to estimate the maximum shear force transmitted across a cracked plane in a concrete member. The expressions to determine the shear friction capacity up to now have been based on experiments on concretes with cylinder strengths of at most f' c = 60 N/mm 2. In such concretes, the aggregate particles normally do not break at the formation of cracks through the concrete. In high-strength concrete, however, the cement matrix is strong enough to cause fracture of the aggregate particles. As a result, the crack faces are relatively smooth, so that the shear friction capacity is expected to be reduced. In this paper, shear friction tests are described on concrete with a cylinder strength of f' c = 100 N/mm 2. The experiments are carried out on cracks in plain concrete and on reinforced cracks. It is shown that the reduction in shear friction capacity due to aggregate fracture is considerable.