Earthquake and earthquake resistant design

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  • 1). Interplate2). Intraplate

    Seismic Waves

    1). Body waves 2). Surface waves

  • 1). Size of Buildings2). Layout of Buildings

  • 1). Earthquake-Resistant Design of BuildingsIt is better to make beams to be the ductile weak links than columns. This method of designing RC buildings is called the strong-column weakbeam design method.

    2). Oscillations of Flexible Buildings

    3). Importance of FlexibilityThe time taken by the wave to complete one cycle of motion is period of the earthquake wave.

  • 1). How to Improve Behavior of Masonry Walls?

  • 2). Influence of Openings

    However, location and size of openings in wallshas significance in deciding the performance of masonry buildings in earthquakes

  • 3). Staircase in building4). Role of Horizontal BandsThe bands are provided to hold a masonry building as a single unit by tying all the walls together.

  • During earthquake shaking, the masonry walls get grouped into three sub-units, namely spandrel masonry, wall pier masonry and sill masonry.1). How Vertical Reinforcement Helps2). Protection of Openings in Walls3). Earthquake Resistant Features3). Earthquake Resistant Features

    a). Ensure proper wall constructionb). Ensure proper bond in masonry coursesc). Provide horizontal reinforcing elementsd). Control on overall dimensions and heights

  • An open ground storey building, having only columns in the ground storey.

    Partition walls and columns in the upper storeys, have two distinct characteristics, namely:a). It is relatively flexible in the ground storey.a). It is relatively flexible in the ground storey.

    b). It is relatively weak in ground storey

    1). The Problem2). Improved design strategies3). The Short Column Behaviour4). The Solution

  • Reinforced concrete (RC) buildings often have vertical plate-like RC walls called Shear Wall in addition to slabs, beams and columns. These walls generally start at foundation level and are continuous throughout the building height. Their thickness can be as low as 150mm, or as high as 400mm in high rise buildings.

    1). Advantages of Shear Walls in RC Buildings2). Architectural Aspects of Shear Walls3). Ductile Design of Shear Walls4). Reinforcement Bars in RC Walls

  • 1). Base IsolationThe idea behind base isolation is to detach the building from the ground in such a way that earthquake motions are not transmitted up through the building, or at least greatly reduced.

    2). Seismic DampersThis are special devices introduced in the building to absorb the This are special devices introduced in the building to absorb the energy provided by the ground motion to the Building.

  • The engineers do not attempt to make earthquake proof buildings that will not get damaged even during the rare but strong earthquake; such buildings will be too robust and also too expensive. Instead, the engineering intention is to make buildings earthquake resistant; suchbuildings resist the effects of ground shaking, although they buildings resist the effects of ground shaking, although they may get damaged severely but would not collapse during the strong earthquake. Thus, safety of people and contents is assured in earthquake-resistant buildings, and thereby a disaster is avoided.