An investigation of Crater Diameter on Plain Slab Foamed Concrete Rice Husk Ash (FCRHA) Exposed to Low Impact LoadingJosef Hadipramana, Abdul Aziz Abdul Samad, Shahrul Niza Mokhatar, Fetra Venny Riza, Noridah Mohamad and Mohd Yusuf Mohd WahabMATEC Web Conf., 103 (2017) 02025DOI: https://doi.org/10.1051/matecconf/201710302025