A Text Book on Graphic StaticsM. C. Clark Publishing Company, 1909 - 316 pages |
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Expressions et termes fréquents
beam bridge center of gravity centroid chord members closing string coefficients compression compressive stress construct dead load stresses deflection diagram determined diagonals equation equilibrium external forces find the stresses force polygon forces acting funicular polygon girder given forces given system graphic inertia influence diagram intercept intersect joint L₂ left end left reaction line of action live load stresses load line load stress diagram lower chord magnitude and direction maximum and minimum maximum bending maximum live load maximum shear maximum stress method moment of inertia moving loads P₁ panel length panel load parabola parallel forces pole distance pounds Pratt truss purlins R₂ radius of gyration represent in magnitude required to find resultant roof truss seen segment Shear Diagram shown in Fig span stress in 2-3 system of forces tension tion triangle truss shown uniform load upper chord Warren truss wind load stress ΣΡ
Fréquemment cités
Page 40 - ... 1. Three forces of 30 pounds, 50 pounds, 90 pounds act at a point, the angle between the directions of any two forces being 120°. Find the magnitude of their resultant, and the angle which its direction makes with the greatest force. 2. Prove that the algebraic sum of the moments of two concurrent forces about any point in their plane is equal to the moment of their resultant about the same point. Forces 2P, P, P act along BC, CA, AB, the sides of an equilateral triangle ABC. Show that the resultant...
Page 40 - The moment of a couple is obviously the product of one of the forces into the perpendicular distance between them. The...
Page 41 - The sum of the moments of a number of parallel coplanar forces about any point in their plane is equal to the moment of the resultant about that point.
Page 63 - Steiner. is true for bath a plane laminar body and a thin three-dimensional body, and states that the moment of inertia of a body about any axis is equal to its moment of inertia about a parallel axis through its...
Page 6 - The Arm of a couple is the perpendicular distance between the lines of action of the two forces...
Page 38 - The moment of a force about any point is the product of the magnitude of the force and the perpendicular distance from the point to the line of action of the force. The...
Page 94 - ... from the principles of statics we know that: 1. The vertical shear V equals the sum of the vertical forces on the left of the cut. 2. The total compression C equals the total tension T. 3. The sum of the moments of the tensile and compressive stresses on the portion shown equals the algebraic sum of the moment of the external forces to the left of the section. From experimental evidence it is known that the unit deformations vary directly as the distance of the fiber from the neutral surface;...
Page 63 - The moment of inertia of an area about any axis is, therefore, determined by adding to the moment of inertia of the area about a parallel axis through the centre of gravity the product of the area into the square of the distance between the two axes.
Page 60 - ... can often be easily carried out by ordinary integration. If A be the area of any plane figure and I its moment of inertia about an axis in its plane, the radius of gyration (k) of the area about that axis is defined by the relation — or k is that value of y at which, if the area A were concentrated, the moment of inertia would be the same as that of the actual figure. Two simple theorems are very useful in calculating moments of inertia of plane figures made up of a combination of a number...
Page 13 - ... polygon must close. For, if it does not close the line joining the initial with the final point represents the resultant of the given forces (Art. 2), and this resultant will cause motion ; and if it does close there exists no resultant. Therefore, if the given forces which meet at a common point are in equilibrium the force polygon must close ; and conversely, if the force polygon closes the given forces must be in equilibrium. When several forces lying in the same plane have different points...