In this paper, the effects of form parameters on the structural efficiency of tall buildings are investigated by generating a parametric platform. The modifications of the form are normally adopted by architects in tall buildings to satisfy their aesthetic and functional needs. The effects of tapering and changing plan shape as two commonly used modifications, are investigated applying the diagrid structural system which provides the structure with high stiffness and efficiency as well as satisfying the architectural needs. Forms are generated in Rhinoceros and exported to SAP2000 to be analysed structurally through a response spectrum analysis. The results show tapering in the height section leads to more impacts on structural efficiency parameters in comparison to plan changes. The circle and the polygons with more sides create more efficient forms. Some outcomes show more than 20% lighter structures in concave sections than normal buildings.

Resilience against natural disasters, such as earthquakes, has been considered as an important goal in sustainable development in recent years. On the other hand, today, sustainability is considered as a main aim in modern architecture. In spite of these facts, the role of sustainable architecture in increasing the resilience of buildings and cities against disastrous events has not been thoroughly discussed so far. In this paper a new natural-base, low cost, eco-friendly and lightweight fiber-reinforced clay (LFRC) material, with high heat, sound and moisture insulation capability, is introduced which its employment can remarkably increase the resilience of buildings against earthquakes. To obtain mechanical properties of the proposed LFRC material, an experimental study was done by conducting a series of tests to measure its bending, shear and compressive strengths. Tests results show that the proposed material has much higher strengths comparing to plain clay and also clay reinforced by some other previously used fibers. The density of the LFRC material is around 1.37 which is less than 75% of the dried plain clay. Building’s components made of the LFRC material can be very helpful for creation of movable partitions or floors/ceilings as well as smart furniture to achieve flexible architecture of special buildings, which is considered as a must in today’s architecture in seismic regions. Because of the relatively high strength and integrity of the LFRC material its usage as the main body of masonry elements, such as load bearing walls in small rural houses and dwellings can also be recommended.

The geometry of skewed and curved bridges can cause complexity of their dynamic response and difficulty of analysis against earthquakes. In addition, when vibration occurs in the curved bridges, due to their specific geometry, the vertical, flexural, and torsional vibrations of the deck are coupled. The present study was carried out aiming to investigate the effect of non-uniform vertical excitation of the bridge piers with various vertical/horizontal acceleration ratio (V/H) on the pounding phenomenon in concrete curved bridges subjected to near-source earthquakes. For this purpose, the analytical method was employed using the expansion of the functions of structural dynamics on a two-span continuous concrete bridge model, consisting of continuous flexural/torsional beam elements for the deck, springs for the rubber bearings, and rods as the bridge piers. The non-uniform vertical excitations of the piers were induced to the whole system by the harmonic functions in the form of transient wave transfer functions, and then the equations of the entire system were solved using the Eigen functions. The induced waves can cause separation of the box girder deck from the rubber bearing along with the vertical and horizontal displacement as well as the torsion of the box girder around the longitudinal axis of the bridge. After each separation, the deck returns back and hit the rubber bearing, resulting in a vertical pounding force on the bearing and the pier. The analyses results show that when the curved beam is subjected to a non-uniform vertical excitation with a various V/H, the lateral displacement of the deck are up to 21% larger than when the bridge is excited by considering a value of V/H = 2/3. The results also show when the excitation frequencies are different in different piers of the bridge, the pounding force can be increased up to three times, for some specific curvature angle, comparing to the case of equal excitation frequency in all piers.