Adib Mahmoodi - M.Sc, Department of Mechanical Engineering, College of Engineering, Kurdistan Science and Research Branch, Islamic Azad University, Sanandaj, Iran.
Reza Azarafza - Asistant Professor, Department of Mechanical Engineering, Malek Ashtar University of Technology, Tehran, Iran
Ali Davar - Asistant Professor, Department of Mechanical Engineering, Malek Ashtar University of Technology, Tehran, Iran

Composite sandwich structures with grid stiffened core (SSGSC) are one of the new structural configurations applied in advanced industries such as aerospace, aviation and automobile industries. Having the benefits of composite sandwich structures, like low density, thermal and acoustical isolation capabilities and high bending stiffness and strength etc., composite (SSGSC) include the advantages of load reconstruction due to the grid stiffened structure in the core. Knowing the dynamic characteristic of these structures is of major concern in advanced industries. Hence, in the present study three composite (SSGSC) samples made of glass/epoxy and carbon/epoxy are fabricated with hand layup method using a silicon rubber die. Also, two metallic samples including a monolithic and a (SSGSC) made of 1050 aluminum are fabricated. The core of aluminum (SSGSC) is produced using wire cut process and the face sheets are stacked using a high grad adhesive.The outside geometry of all five samples considered are same (300×232.5mm). The experimental modal testing is achieved on all the samples using B&K vibration testing equipment. The frequency response, mode shape as well as damping coefficients are obtained from each experiment. Detailed discussions and comparisons are carried out on the new interesting results of the experiments.

Composite sandwich structures with grid stiffened core (SSGSC), grid Structure, Modal Experiment, Hand Lay-up, Frequency Response