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Bernard J. Hamrock , Elementos de máquinas. Ed. Mc Graw Hill. Robert L. Norton , Diseño de máquinas. Ed. Prentice Hall. Shigley , Diseño en Ingeniería Mecánica, Ed. Mc Graw-Hill. BIBLIOGRAFIA de referencia. Load, Stress and Strain. When I am working on a problem, I never think
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Bernard J. Hamrock, Elementos de máquinas. Ed. Mc Graw Hill. Robert L. Norton, Diseño de máquinas. Ed. Prentice Hall. Shigley, Diseño en Ingeniería Mecánica, Ed. Mc Graw-Hill BIBLIOGRAFIAde referencia
Load, Stress and Strain When I am working on a problem, I never think about beauty. I only think of how to solve the problem. But when I have finished, if the solution is not beautiful, I know it is wrong. Richard Buckminster Fuller Image: A dragline lifts a large load in a mining operation.
A Simple Crane Figure 2.1 A simple crane and forces acting on it. (a) Assembly drawing; (b) free-body diagram of forces acting on the beam. text reference: Figure 2.1, page 30
Load Classification Figure 2.2 Load classified as to location and method of application. (a) Normal, tensile (b) normal, compressive; (c) shear; (d) bending; (e) torsion; (f) combined text reference: Figure 2.2, page 31
Sign Convention Figure 2.3 Sign convention used in bending. (a) y coordinate upward; (b) y coordinate downward. text reference: Figure 2.3, page 32
Lever Assembly Figure 2.4 Lever assembly and results. (a) Lever assembly; (b) results showning (1) normal, tensile, (2) shear, (3) bending, (4) torsion on section B of lever assembly. text reference: Figure 2.4, page 33
Supports and Reactions Table 2.1: Four types of support with their corresponding reactions. text reference: Table 2.1, page 35
Ladder Free Body Diagram Figure 2.5: Ladder having contact with the house and the ground while having a painter on the ladder. Used in Example 2.4. The ladder length is l. text reference: Figure 2.5, page 36
External Rim Brake and Forces Figure 2.6 External rim brake and forces acting on it. (a) External rim brake; (b) external rim brake with forces acting on each part. (Linear dimensions are in millimeters.) text reference: Figure 2.6, page 38
Sphere and Forces Figure 2.7 Sphere and forces acting on it. (a) Sphere supported with wires from top and a spring at the bottom; (b) free-body diagram of forces acting on the sphere. Figure used in Example 2.6. text reference: Figure 2.7, page 38
Beam Supports Figure 2.8 Three types of beam support. (a) Simply supported; (b) cantilevered; (c) overhanging. text reference: Figure 2.8, page 39
Simply Supported Bar Figure 2.9 Simply supported bar with (a) midlength load and reactions; (b) free-body diagram for 0<x<l/2; (c) free body diagram for l/2<x<l; (d) shear and bending moment diagrams. text reference: Figure 2.9, page 40
Singularity Functions (Part 1) Table 2.2 Six singularity and load intensity functions with corresponding graphs and expressions. text reference: Table 2.2, page 43
Singularity Functions (Part 2) Table 2.2 Six singularity and load intensity functions with corresponding graphs and expressions. text reference: Table 2.2, page 43
Shear and Moment Diagrams Figure 2.10 (a) Shear and (b) moment diagrams for Example 2.8. text reference: Figure 2.10, page 44
Simply Supported Beam Figure 2.11 Simply supported beam. (a) Forces acting on beam when P1=8kN, P2=5kN; w0=4kN/m; l=12m; (b) free-body diagram showing resulting forces; (c) shear and (d) moment diagrams of Example 2.9. text reference: Figure 2.11, page 46
Example 2.10 Ø6mm □25mm Ø10mm Figure 2.12 Figures used in Example 2.10. (a) Load assembly drawing; (b) free-body diagram. text reference: Figure 2.12, page 48
Example text reference: Figure 2.12, page 48
General State of Stress Figure 2.13 Stress element showing general state of three-dimensional stress with origin placed in center of element. text reference: Figure 2.13, page 49
2-D State of Stress Figure 2.14 Stress element showing two-dimensional state of stress. (a) Three dimensional view; (b) plane view. text reference: Figure 2.14, page 51
Equivalent Stresses Figure 2.15 Illustration of equivalent stresss states; (a) Stress element oriented in the direction of applied stress. (b) stress element oriented in different (arbitrary) direction. text reference: Figure 2.15, page 52
Stresses in Oblique Plane Figure 2.16 Stresses in oblique plane at angle . text reference: Figure 2.16, page 52
Mohr’s Circle Figure 2.17 Mohr’s circle diagram of Eqs. (2.13) and (2.14). text reference: Figure 2.17, page 55
Results from Example 2.13 Figure 2.18 Results from Example 2.13 (a) Mohr’s circle diagram; (b) stress element for principal normal stresses shown in x-y coordinates; (c) stress element for principal stresses shown in x-y coordinates. text reference: Figure 2.18, page 57
Mohr’s Circle for Triaxial Stress State Figure 2.19 Mohr’s circle for triaxial stress state. (a) Mohr’s circle representation; (b) principal stresses on two planes. text reference: Figure 2.19, page 59
Example 3.5 Figure 2.20 Mohr’s circle diagram for Example 3.5. (a) Triaxial stress state when 1=23.43 ksi, 2=4.57 ksi, and 3=0; (b) biaxial stress state when 1=30.76 ksi and 2=-2.760 ksi; (c) triaxial stress state when 1=30.76 ksi, 2=0, and 3=-2.76 ksi. text reference: Figure 2.20, page 60
Stresses on Octahedral Planes Figure 2.21 Stresses acting on octahedral planes. (a) General state of stress. (b) normal stress; (c) octahedral shear stress. text reference: Figure 2.21, page 61
Normal Strain Figure 2.22 Normal strain of cubic element subjected to uniform tension in x direction. (a) Three dimensional view; (b) two-dimensional (or plane) view. text reference: Figure 2.21, page 64
Shear Strain Figure 2.23 Shear strain of cubic element subjected to shear stress. (a) Three dimensional view; (b) two-dimensional (or plane) view. text reference: Figure 2.23, page 65
Plain Strain Figure 2.24 Graphical depiction of plane strain element. (a) Normal strain x; (b) normal strain y; and (c) shear strain xy. text reference: Figure 2.24, page 66
Circular Bar with Tensile Load Figure 4.10 Circular bar with tensile load applied. text reference: Figure 4.10, page 149
Twisting due to Applied Torque Figure 4.11 Twisting of member due to applied torque. Hipotesis de Coulomb: secciones transversales circulares, permanecen planas. Principio de Saint Venant: secciones transversales no circulares. text reference: Figure 4.11, page 152
Bending of a Bar Figure 4.12 Bar made of elastomeric material to illustrate effect of bending. (a) Undeformed bar; (b) deformed bar. text reference: Figure 4.12, page 156
Bending in Cantilevered Bar Figure 4.13 Bending occurring in cantilevered bar, showing neutral surface. text reference: Figure 4.13, page 157
Elements in Bending Figure 4.14 Undeformed and deformed elements in bending. text reference: Figure 4.14, page 157
Bending Stress Distribution Figure 4.15 Profile view of bending stress variation. text reference: Figure 4.15, page 158
Example 4.10 Figure 4.16 U-shaped cross section experiencing bending moment, used in Example 4.10. text reference: Figure 4.16, page 159
Curved Member in Bending text reference: Figure 4.17, page 161
Curved Member in Bending Condición: sumatorio de esfuerzos en el rn=0
Cross Section of Curved Member Figure 4.18 Rectangular cross section of curved member. text reference: Figure 4.18, page 162
Example: Cross Section of Curved Member • Una sección transversal rectangular de un elemento curvo, tiene las dimensiones: • b= 1´ y h=r0-ri=3´, sometida a un momento de flexión puro de 20000lbf-pulg. • Hallar: • Elemento recto. • Elemento curvo. r=15´. • Elemento curvo. r=3´. text reference: Figure 4.18, page 162
Example: Cross Section of Curved Member • Una sección trapezoidal de un elemento curvo, tiene las dimensiones: • ri=10 cm • F= 125 kg • Tadm=1380 Kg/cm2 • Hallar: valor de a. text reference: Figure 4.18, page 162
Development of Transverse Shear Figure 4.19 How transverse shear is developed. text reference: Figure 4.19, page 165
Deformation due to Transverse Shear Figure 4.20 Cantilevered bar made of highly deformable material and marked with horizontal and vertical grid lines to show deformation due to transverse shear. (a) Undeformed; (b) deformed. text reference: Figure 4.20, page 166
Moments and Stresses on Elements Figure 4.21 Three-dimensional and profile views of moments and stresses associated with shaded top segment of element that has been sectioned at y’ about neutral axis. (a) Three-dimensional view; (b) profile view. text reference: Figure 4.21, page 166
Maximum Shear Stress Table 4.3 Maximum shear stress for different beam cross sections. text reference: Table 4.3, page 168
Strain Gage Rosette Figure 2.25 Strain gage rosette used in Example 2.17. text reference: Figure 2.25, page 68