Study on Design Relations of Structural Lghtweight Self-Compacting Concrete Beams Containing Light Expanded Clay and EPS

The use of lightweight materials in construction industry reduces dead weight of structure and earthquake force acting upon it. On the other hand, the use of lightweight aggregates consider as a way to conserve existing natural aggregate mines. Self-CompactingConcrete (SCC) isa new type ofhighperformanceconcretes that flowsunderits own weight, passes through the reinforcements and fills all the corners of frameworks completely, The use of SCC is growing increasingly because of its great advantagessuch as eliminating the vibration of the concrete, reducing noise pollutionduring the construction time, having high workability and et. In this paper the effects of using two different artificial lightweight materials including light Expanded Clay Aggregates (LECA) and Expanded Poly-Styrene (EPS) on SCC are investigated. Fresh concrete requirement and the possibility of classification as lightweight self compacting concrete at hardened condition is determined.in order to evaluate structural lightweight self compacting beams, reinforced concrete beams were made of LECA and EPS and their design coefficient, bending capacity, modulus of rupture and deflection, compared with the normal weight SCC and also compared with the corresponding calculated values based on ACI 318.The results Shaw that the proposed relationships by ACI 318 code, are reliable when LECA is applied as lightweight aggregates, In this type of concrete, coefficient of lightweight concrete (λ) and bending capacity calculated by ACI 318 is smaller than corresponding experimental values, and calculated deflection is greater than experimental deflection. but the proposed design relationships by ACI 318 code, aren’t reliable when EPS is applied as lightweight aggregates, In EPS concrete, coefficient of lightweight concrete (λ), bending capacity and modulus of rupture calculated by ACI 318 is greater than corresponding experimental values.