The performance of a 2D metamaterial (MTM) structure using finite element method (FEM) and transmission line model (TLM) is investigated in this paper. The size of the proposed unit cell is 4 mm × 4 mm to resonant around 12 GHz. The unit cell is constructed from a patterned patch and solid ground plane that are connected with via through an FR-4 substrate. The unit cell is characterized from 11 GHz to 14 GHz in terms of S-parameters, effective refractive index, and dispersion properties. It is found that the proposed unit cell behaves like unbalanced case of a passive constant k band elimination filter. Moreover, it is found that the unit cell exhibits no negative refractive index (NRI) over a wide range of frequencies; however, it shows a less than 1 refractive index over then same frequency range. A theoretical investigation based on TLM is developed to extract the values of the basic lumped, RLC, elements network.

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Recently, modern wireless communication applications are extended to call high frequency bands including millimeter waves for 5G systems. Therefore, the propagation properties of such waves in different media have attracted many researchers. In this work, the results of the Sparameters measurements of mortar with four thicknesses are obtained using a nondestructive free space measurement technique for the frequency bands from 8 GHz up to 32 GHz. The obtained results of the dielectric properties and loss factors for the prepared mortar samples are realized. The variation in both the reflection and transmission coefficients and the dielectric properties with curing time conditions of mortar structure is examined. The dielectric properties of water are realized using the proposed method to subtract the effects of water contents from the prepared mortar samples. The effects of the sample thickness and relaxation frequency are considered. The obtained measurements are compared to the simulated results based on a full wave simulation software package of CSTMWS algorithms. Finally, excellent agreements are achieved between the simulated and measured results.

However though the structures are supported on soil, most of the designers do not consider the soil structure interaction and its subsequent effect on structure during an earthquake. Different soil properties can affect seismic waves as they pass through a soil layer. When a structure is subjected to an earthquake excitation, it interacts the foundation and soil, and thus changes the motion of the ground. It means that the movement of the whole ground structure system is influenced by type of soil as well as by the type of structure. Tall buildings are supposed to be of engineered construction in sense that they might have been analyzed and designed to meet the provision of relevant codes of practice and building bye-laws. IS 1893: 2002 “Criteria for Earthquake Resistant Design of Structures” gives response spectrum for different types of soil such as hard, medium and soft. An attempt has been made in this paper to study the effect of Soil-structure interaction on multi storeyed buildings with various foundation systems. Also to study the response of buildings subjected to seismic forces with Rigid and Flexible foundations. Multi storeyed buildings with fixed and flexible support subjected to seismic forces were analyzed under different soil conditions like hard, medium and soft. The buildings were analyzed by Response spectrum method using software SAP2000. The response of building frames such as Lateral deflection, Story drift, Base shear, Axial force and Column moment values for all building frames were presented in this paper.

Though the structures are supported on soil, most of the designers do not consider the soil structure interaction and its subsequent effect on the structure during an earthquake. Different soil properties can affect seismic waves as they pass through a soil layer. When a structure is subjected to an earthquake excitation, it interacts with the foundation and soil, and thus changes the motion of the ground. It means that the movement of the whole ground structure system is influenced by type of soil as well as by the type of an engineering structure. Tanks are supposed to be of construction in sense that they might have been analyzed and designed to meet the provision of relevant codes of practice and building bye-laws. IS 1893: 2002 “Criteria for Earthquake Resistant Design of Structures” gives response spectrum for different types of soil such as hard, medium and soft. An attempt has been made in this paper to study the effect of Soil-structure interaction on multi storeyed buildings with various foundation systems as well as to study the response of buildings subjected to seismic forces with Rigid and Flexible foundations. Tanks with fixed and flexible support subjected to seismic forces were analysed under different soil conditions like hard, medium and soft. The buildings were analysed by Response spectrum method using software by ABAQUS program . A structural model using the generalized single degree of freedom (SDF) system is proposed for seismic design of concrete rectangular Liquid Containing Structures (LCS). The proposed model considers the effect of flexibility of tank wall on hydrodynamic pressures and uses the consistent mass approach. The proposed model is compared with the results obtained using the current practice as well as the finite element method. It is concluded that the current approach in design codes and standards does not truly represent the behaviour of LCS. The proposed model using the generalized SDF system can be simply used in seismic design of LCS.