International Concrete Abstracts Portal

Title: Early Age Shear-Friction Behavior of High-Strength Concrete Layered Systems at Sub-Freezing Temperatures

Author(s): Shivaprasad T. Kudlapur and Edward F. Nawy

Publication: Special Publication

Volume: 133

Issue:

Appears on pages(s): 159-186

Keywords: cold weather concreting; friction; high-strength concretes; magnesium; methyl methacrylate; polymer concrete; shear properties; shear strength; shear stress; stress transfer; Structural Research

Date: 9/1/1992

Abstract:
Studies are limited on the early age performance of high-strength cold weather concretes and their shear strength interaction in cold weather. This paper presents shear transfer strength characteristics between regular high-strength concrete and (i) methyl methacrylate-based polymer concrete and (ii) magnesium phosphate based concrete in subfreezing temperatures. Analytical expressions were developed based on shear transfer hypothesis and verified by experimental results. The experimental study included tests on cylinders and L-shaped push off specimens to determine the early age shear interlock and shear frictional resistance between high-strength regular portland cement concrete and cold weather high-strength concretes as is experienced in rehabilitation of bridge decks and other infrastructure systems. Studies indicated that at early age of 24 hours, shear transfer strength of 1400 psi can be obtained with the use of appropriate material and shear reinforcement. The study also indicated the ACI 318-89 code limits on the shear-friction strength are too conservative even at early ages for high-strength cold weather concretes.