Shear transfer strength of alkali-activated slag-based concrete

As a part of ongoing research to apply alkali-activated slag-based concrete in building structures, the shear transfer behavior of alkali-activated slag-based concrete was experimentally examined through the push-off tests of 32 initially uncracked reinforced planes. The test parameters were concrete type, concrete strength, shear reinforcement ratio, and shear plane size. The test results and comparative analysis showed that the shear strength of reinforced alkali-activated slag-based concrete (AAC) was comparable to Portland cement concrete (PCC) counterparts. However, AAC planes cracked earlier and displayed larger crack separation at the peak load, which is attributed to higher cracking prevalence and brittleness of AAC. Both the increase of concrete strength and lateral constraint stress promotes the development of shear strength in reinforced planes, and their effect is interactional. The shear strength decreased as the shear plane width and depth increased. The existing strength models from design codes and literatures for the shear transfer strength of PCC are still applicable to reinforced AAC planes. Among them, AASHTO LRFD Bridge Design Specifications and the nonlinear model proposed by Mau and Hsu gave better predictions of the measured shear strengths of AAC.