a) The design of an engineering structure must ensure that, under the worst loadings the structure...

 

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a) The design of an engineering structure must ensure that, under the worst loadings the structure is safe, and during normal working conditions the deformation of the members does not detract from the appearance, durability or performance of the structure. Despite the difficulty in assessing the precise loading and variations in the strength of the concrete and steel, these requirements have to be met. If one of the design philosophies used by civil engineers is permissible stress, what is permissible stress in strength of materials? CR[7] b) The limit state method of design overcomes many of the disadvantages of permissible stress and load factor methods. This is done by applying partial factors of safety, both to the loads and to the material strengths, and the magnitude of the factors may be varied so that they may be used either with the plastic conditions in the ultimate state or with the more elastic stress range at working loads. This flexibility is particularly important if full benefits are to be obtained from development of improved concrete and steel properties. Spell out the drawbacks and disadvantages of the two methods. CR[7] c) A structure designed by employing limit state method of collapse and checked for other limit states will ensure the strength and stability requirements at the collapse under the design loads and also deflection and cracking at the limit state of serviceability. This will help to achieve the structure with acceptable probabilities that the structure will not become unfit for the use for which it is intended. How is working stress method different from limit state method ? CR[6] TOTAL 120 MARKSI a) The design of an engineering structure must ensure that, under the worst loadings the structure is safe, and during normal working conditions the deformation of the members does not detract from the appearance, durability or performance of the structure. Despite the difficulty in assessing the precise loading and variations in the strength of the concrete and steel, these requirements have to be met. If one of the design philosophies used by civil engineers is permissible stress, what is permissible stress in strength of materials? CR[7] b) The limit state method of design overcomes many of the disadvantages of permissible stress and load factor methods. This is done by applying partial factors of safety, both to the loads and to the material strengths, and the magnitude of the factors may be varied so that they may be used either with the plastic conditions in the ultimate state or with the more elastic stress range at working loads. This flexibility is particularly important if full benefits are to be obtained from development of improved concrete and steel properties. Spell out the drawbacks and disadvantages of the two methods. CR[7] c) A structure designed by employing limit state method of collapse and checked for other limit states will ensure the strength and stability requirements at the collapse under the design loads and also deflection and cracking at the limit state of serviceability. This will help to achieve the structure with acceptable probabilities that the structure will not become unfit for the use for which it is intended. How is working stress method different from limit state method ? CR[6] TOTAL 120 MARKSI

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1Permissible stress design is a design philosophy used by civil engineers It is us... View the full answer