The study is conducted to perform two goals: The first is to produce a lightweight concrete using major components which are locally available with some standard admixtures. Many mixtures are prepared using many ratios of superplasticizer (SP) and silica fume (SF) admixtures to yield a lightweight aggregate concrete, the effects of using different ratios of these admixtures on unit weight, compressive strength and flexural strength are studied individually and accumulatively. The second is the study of dynamic specifications of normal and lightweight reinforced concrete beams.