Effects of Laminate Arrangement on the Failure Behaviour of Hybrid Composite Plates under Transverse Sinusoidal Load

The present work deals with the effects of laminate arrangement on the failure behaviour of hybrid composite plates under transverse sinusoidal load. Failure analysis has been a subject under study for many years, especially for composite materials. This is largely due to the spontaneous nature of composite materials when it fails without warning. Hybrid composite are commonly utilized to improve the unexpected and instantaneous failure mode of composites. Nevertheless, the failure behaviour of hybrid composites is still not well understood. Moreover, studies have not exploited the effects on sinusoidal transverse loading on hybrid composites. Therefore, the first and last ply failure of the hybrid composite laminate was simulated and analysed using built in failure criteria function in ANSYS. The hybrid composite consisted of graphite (GR) and glass (GL), with lamination schemes of [GL/GL/GL/GL], [GL/GL/GL/GR] and [GR/GL/GL/GL] were subjected of transverse sinusoidal loading.  The laminate failure was predicted using the Maximum Stress Theory. Prior to determining the first and last ply failure of the hybrid composite plate, numerical validation was conducted to ensure the accuracy of the finite element software. The failure curves of the first ply failure and last ply failure were plotted and the results showed significant difference in the correlation of loadings that caused first and last ply failures and the lamination scheme of the hybrid composite plates. Thus, it can be said that the present work proves to be of importance and valuable in the field of study as well as enriching the knowledge regarding the failure behaviour of hybrid composite plate under transverse sinusoidal load of different laminate arrangement

Flume investigation on bed load transport and bedforms in simple channels

Massive floods hit various states in Malaysia such as Pahang, Kelantan, Johor, Terengganu, Sabah and Sarawak. It caused widespread damages to properties, infrastructures, human suffering and even deaths. More frequent floods incidents and soil erosion are reported which lead to sedimentation problems in the drainage and river systems due to urbanisation. It is important to understand the sedimentation process and the behaviour of bed forms in the water course for post-flood events. However, it is risky and dangerous to conduct field study during occurrence of flooding. Laboratory study has been chosen as an alternative to fulfill the objectives. Experimental investigations on the bed load transport and bed forms in simple channels have been undertaken. Small and large flume models are used in the laboratory. The effects of flow on mobile sandy bed channel and bed load transportation are studied by using a modified flume with an asymmetric straight compound channel. However, the findings on rate of transport and bed formation for non-flooding cases are presented in this paper. It is found that the bed formation profiles for both channels are different due to scale and flume characteristics. The bed forms, erosion and deposition processes are significantly influenced by the water velocity in the channel. The bed forms observed for large flume are repeating ripples and dunes; meanwhile variable of ripples are observed in small flume