1. Analysis of Statically Determinate Trusses (part 1)
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Analysis of Statically Determinate Trusses (part 1)
12/3/2018
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2. 1. Common types of Trusses:
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3. 1.1 Roof Trusses:
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6. 1.2 Bridge Trusses:
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9. Assumptions for design:
1. The members are joined together by smooth pins.
2. All loadings are applied at the joints
Because of these two assumptions, each truss member acts as an axial force member
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10. Classification of coplanar trusses:
A simple truss is constructed by starting with a basic triangular element, such as ABC in Fig. below, and connecting two members (AD and BD) to form an additional element
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11. Dr. Nasrellah H A
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12. A compound truss is formed by connecting two or more simple trusses together. Quite often this type of truss is used to support loads acting over a large span
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13. A complex truss is one that cannot be classified as being either simple or compound
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14. Method of Joints:
If a truss is in equilibrium, then each of its joints must also be in
equilibrium. Hence, the method of joints consists of satisfying the
equilibrium conditions
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17. Joint A:
Joint G:
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18. Joint B:
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19. Zero force members:
zero-force members may be necessary for the stability of the truss during construction and to provide support if the applied loading is changed.
The zero-force members of a truss can generally be determined by
inspection of the joints, and they occur in two cases.
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20. Case 1: If there are any two members are connected together at a r and there is no external load or support reaction on the joint, These tow members become a zero-force members.
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21. Case 2: if three members form a truss joint for which two of the members are collinear, the third member is a zero-force member, provided no external force or support reaction is applied to the joint
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