Structural mechanics-force diagram,shear stress,elastic curve


by wkh023002
Tags: curve, diagram, elastic, mechanicsforce, shear, stress, structural
wkh023002
wkh023002 is offline
#1
Nov25-07, 09:33 AM
P: 10
There are totally 4 questions .i struggled for a whole day and i still cannot solve it.Please help me!
For Question 1:
My problem is that i cannot find out the reaction Ax,Ay,Dx,Dy though i establish 4 eqt:
1:Ax+Dx=90 kN
2:Ay+Dy=90 kN
3:summation Ma=0 ,anticlockwise positve
-125+2Dx+5Dy=0
4:summation Md=0 ,anticlockwise +ve
505-2Ax-5Ay=0

For Question 2:
i dunno what is the meaning of G=80kN/mm^2 and how to calculate the shear force?
also, what is Bredt-Batho theory? My professor haven't mentioned it so far.

For Question 4:
The first load from left P=WL/5 is outside the Y-axis, does it mean that i can neglect it?
to find the equation of elastic curve, do i need to establish the Moment equation for each section?
Attached Files
File Type: pdf 2955711425.pdf (24.5 KB, 33 views)
Phys.Org News Partner Science news on Phys.org
NASA's space station Robonaut finally getting legs
Free the seed: OSSI nurtures growing plants without patent barriers
Going nuts? Turkey looks to pistachios to heat new eco-city
PhanthomJay
PhanthomJay is offline
#2
Nov25-07, 02:34 PM
Sci Advisor
HW Helper
PF Gold
PhanthomJay's Avatar
P: 5,963
For question 1, in 2 dimensional frames, there are only 3 equations of statics external to the system that you can use in solving for external reactions...sum of Fx=0, sum of Fy=0, and sum of moments about any point = 0. The 4th equation you list is redundant. Since there are 4 unknowns, you must look at what is going on internal to the system to get your 4th equation. What do you know about the moment at the hinged joint C?


Register to reply

Related Discussions
Structural mechanics; stress distribution on a cross section; locating shear centre Engineering, Comp Sci, & Technology Homework 0
shear force bending moments diagram help? Introductory Physics Homework 2
Fluid Mechanics question (shear stress) Engineering, Comp Sci, & Technology Homework 3
Shear Force and bending moment diagram General Engineering 2
compressional stress & shear stress Introductory Physics Homework 1