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Analysis of truss using the method of joint

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The analyzing of truss structure using the method of joint done by drawing the free body diagram for truss joint and calculating unknown forces using equilibrium equations ΣFx=0, ΣFy=0, if the truss in equilibrium state this means that each joint in equilibrium, we should begin by isolating and analyzing joints with at least one known forces and the most two unknown forces. Truss members will exert axial forces on joints, the line of action of these forces is determined from the geometry of the truss. The inclined forces will be divided into two component X component and y component, then we will use the equilibrium equation to calculate unknown forces. It is preferred to assume all members acting on the joint are in tension. If the numerical solution for the force is positive, then the force is in tension, but if the result of the numerical solution is negative, then the force is in compression. The example below explains the method of joint. For reactions in support, we should use the third equilibrium equation ΣM=0 to determine unknown reactions.









Example 1

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