COMPLETE ETABS TUTORIALS : https://www.youtube.com/watch?v=zq0YbxzFN_I&list=PLDyhMW3kzPDAOR0UYuJaFNxv0e3cPlcUH How to check drift limit due to earthquake – Seismic Drift : https://www.youtube.com/watch?v=-yYZeNScCaE How to check drift limit due to earthquake – wind Drift Check for seismic drift limitations Etabs tutorial for drift check Define wind load for drift Wind serviceability check Structural stability check How to check for drift limitation in etabs Complete guide to drift check using etabs What is drift in structural engineering What is Global drift What is inter story drift What is inter story drift ratio What is global drift ratio WHAT IS DRIFT? 1. GLOBAL DRIFT : Displacement of top story w.r.t foundation 2. INTERSTOREY DRIFT : Displacement of one story w.r.t adjacent story displacement 3. GLOBAL DRIFT RATIO : Ratio of Displacement of top story w.r.t foundation and the building height 4. INTERSTOREY DRIFT RATIO : Ratio of displacement of one story w.r.t adjacent story displacement and Elevation difference between the two stories SEISMIC DRIFT LIMIT CHECK UBC-97 UBC 97 imposes the drift limitation on inter story drift ratio: Maximum inelastic drift Elastic and inelastic drift ratio 0.002 for structures L/400 to L/600 Ce = combined height, exposure and gust factor coefficient as given in Table 16-G. Cq = pressure coefficient for the structure or portion of structure under consideration as given in Table 16-H. Iw = importance factor as set forth in Table 16-K. P = design wind pressure. qs = wind stagnation pressure at the standard height of 33 feet (10 000 mm) as set forth in Table 16-F. Every structure shall be designed for the pressures calculated using Formula and the pressure coefficients, Cq, of either Method 1 or Method 2. In addition, design of the overall structure and its primary load-resisting system . The base overturning moment for the entire structure, or for any one of its individual primary lateral-resisting elements, shall not exceed two thirds of the dead-load-resisting moment. For an entire structure with a height-to-width ratio of 0.5 or less in the wind direction and a maximum height of 60 feet (18 290 mm), the combination of the effects of uplift and overturning may be reduced by one third. The weight of earth superimposed over footings may be used to calculate the dead-load-resisting moment. Method 1 (Normal Force Method). Method 1 shall be used for the design of gabled rigid frames and may be used for any structure. In the Normal Force Method, the wind pressures shall be assumed to act simultaneously normal to all exterior surfaces. For pressures on roofs and leeward walls, Ce shall be evaluated at the mean roof height. Method 2 (Projected Area Method). Method 2 may be used for any structure less than 200 feet (60 960 mm) in height except those using gabled rigid frames. This method may be used in stability determinations for any structure less than 200 feet (60 960 mm) high. In the Projected Area Method, horizontal pressures shall be assumed to act upon the full vertical projected area #etabs #engineering #design