The applicability of steel slag for concrete lining in tunnels

Abstract

Steel slag is a waste product of steel refineries. It is usually in the form of particels and fine praticles, so it is easy to mix in concrete. It has also a high-density, easily sinks in the concrete mixture, and pass through the gaps between the steel bars. It is very good for application in Self - Compacting Concrete (SCC). This research shows that the obtained compressive strength of steel slag Self - Compacting Concrete are (29.3035.97) Mpa and (30.35÷37.37)Mpa with concrete M300 and M400 respectively. Elastic modulus of steel slag SCC M300 and M400 are 33.38 MPa and 38.58 MPa at the age of 28 days. The flexural tensile strength of samples of size B x H x L = 150 x 300 x 600 mm is 42.37 MPa and 46.9 MPa with the concrete M300 and M400 respectively. Received surface abrasion of samples contained from 0.34 and 0.30 g/cm3 with the steel slag SCC M300 and M400. The above values of steel slag SCC are equivalent or even higher than that of the conventional concrete. In addition, the workability of them is also higher than that of conventional concrete. Hence, steel slag SCC is completely applicable for concrete linings of underground constructions, especially those with long service life such as traffic tunnels, requiring with water and waterproof properties. It allows taking advantage of waste products, improving the environment in steel factory in Vietnam in general and of Ba Ria Vung Tau province in particular.