Experimental Investigation of the Blast Furnace Slag Based Concretes Filled in the Thin Walled Steel Stubs

Abstract

The upgrading of blast furnace waste as a substitute material contributes to safeguard a large part of the natural resources and to protect the environment. A test program has been undertaken in order to assess the effects of the use of slag in the manufacture of concrete on their mechanical and water properties; three concrete mixtures have been studied, normal concrete, concrete slag where the gravel and sand were substituted by crystallised slag, and a slag sand concrete where sand dune has been substituted by crushed crystallised slag sand. In addition, a series of tests on cold rolled steel stubs of rectangular section filled with these three types of concretes has been made, in order to study their behavior under axial compression load. The main studied parameters have been the effect of the in filled concrete and its age (28 days and 180 days). The experimental results have showed that using granulated and crystallized slag has an influence on the concrete properties and it improves load carrying capacity for composite stubs at 180 days of age. A comparison is made with the predicted ultimate strengths of composite tubs using the EC4 code.