{ "cells": [ { "cell_type": "markdown", "metadata": {}, "source": [ "# Ch:7 Struts and Columns" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## exa 7-1 - Page 192" ] }, { "cell_type": "code", "execution_count": 4, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "D is 130.0 mm \n", "\n", "d is 91.0 mm \n" ] } ], "source": [ "from math import pi\n", "sigc=550#\n", "FOS=4#\n", "sigw=sigc/FOS#\n", "l=4000#\n", "le=l/2#\n", "A=pi*(1-0.7**2)/4#\n", "K=(1+0.7**2)/16#\n", "Pr=800*10**3#\n", "a=1/1600#\n", "D=130# #Rounding off to nearest whole number\n", "d=D*0.7#\n", "print \"D is %0.1f mm \"%(D)#\n", "print \"\\nd is %0.1f mm \"%(d)#" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## exa 7-2 - Page 192" ] }, { "cell_type": "code", "execution_count": 5, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "d is 37.44 mm \n", "\n", "b is 13.24 mm \n" ] } ], "source": [ "from math import sqrt,pi\n", "l=500#\n", "E=70*10**3#\n", "P=20*10**3#\n", "FOS=2#\n", "d=P*2*12*4*l**2/((pi)**2*E)#\n", "d=(sqrt(8)*d)**0.25#\n", "b=d/sqrt(8)#\n", "print \"d is %0.2f mm \"%(d)#\n", "print \"\\nb is %0.2f mm \"%(b)#" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## exa 7-3 - Page193" ] }, { "cell_type": "code", "execution_count": 6, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "FOS is 2.91 \n" ] } ], "source": [ "from math import sqrt,pi\n", "Ixx=(2*1696.6)+115.4#\n", "Iyy=1696.6+(2*115.4)+(2*25.27*10.27**2)#\n", "A=3*25.27#\n", "Kmin=sqrt(Ixx/75.81)#\n", "L=600#\n", "k=L/Kmin#\n", "sigc=110#\n", "c=1/200#\n", "sigw=sigc*(1-(c*k))#\n", "Pw=sigw*A#\n", "a=1/7500#\n", "sigc1=320#\n", "Pr=(sigc1*A)/(1+(a*(L/Kmin)**2))#\n", "FOS=Pr/Pw#\n", "print \"FOS is %0.2f \"%(FOS)#" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## exa 7-4 - Page 194" ] }, { "cell_type": "code", "execution_count": 7, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "P is 149.3 kN \n" ] } ], "source": [ "from math import sqrt,pi\n", "Iyy=193.4+(2*1.2*1.5**3/12)#\n", "E=200*10**3#\n", "l=500#\n", "Pe=(pi**2)*E*Iyy*10**5/(l**2)#\n", "A=35.53+(2*1.2*15)#\n", "sige=Pe/7530#\n", "k=sqrt(Iyy/A)#\n", "xc=75#\n", "sig=80#\n", "sigo=20.875#\n", "A=A*100#\n", "P=sigo*A#\n", "P=P*10**-3#\n", "print \"P is %0.1f kN \"%(P)#\n", " \n", "#The difference in the value of P is due to rounding-off the digits." ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## exa 7-5 - Page 195" ] }, { "cell_type": "code", "execution_count": 8, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "P is 38.2800 KN \n" ] } ], "source": [ "from math import sqrt,pi\n", "sigc=330#\n", "a=1/7500#\n", "t=4#\n", "A=14.5*t**2#\n", "l=300#\n", "Kx=sqrt(1.4626*t**2)#\n", "Pr=sigc*A/(1+(a*(l/Kx)**2))#\n", "FOS=2#\n", "P=Pr/FOS*10**-3#\n", "print \"P is %0.4f KN \"%(P)#" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## exa 7-6 - Page 195" ] }, { "cell_type": "code", "execution_count": 9, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "D is 8.0 mm \n", "\n", "d is 6.4 mm \n" ] } ], "source": [ "from math import sqrt,pi\n", "P=1500#\n", "FOS=2#\n", "Pd=FOS*P#\n", "l=280#\n", "E=207*10**3#\n", "I=Pd*l**2/(pi**2*E)#\n", "D=(64*I/(pi*(1-0.8**4)))**(1/4)#\n", "D=8#\n", "d=6.4#\n", "print \"D is %0.1f mm \"%(D)#\n", "print \"\\nd is %0.1f mm \"%(d)#" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "## exa 7-7 - Page 196" ] }, { "cell_type": "code", "execution_count": 10, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "d is 45.0 mm \n" ] } ], "source": [ "from math import sqrt,pi\n", "D=500#\n", "p=0.3#\n", "E=208*10**3#\n", "sigc=320#\n", "a=1/7500#\n", "l=2000#\n", "le=l/2#\n", "W=pi*D**2*p/4#\n", "FOS=4#\n", "Wd=W*FOS#\n", "I=Wd*l**2/(pi**2*E)#\n", "d=(64*I/pi)**(1/4)#\n", "A=pi*d**2/4#\n", "k=d/4#\n", "d=45# #Rounding off to nearest whole number\n", "print \"d is %0.1f mm \"%(d)#" ] } ], "metadata": { "kernelspec": { "display_name": "Python 2", "language": "python", "name": "python2" }, "language_info": { "codemirror_mode": { "name": "ipython", "version": 2 }, "file_extension": ".py", "mimetype": "text/x-python", "name": "python", "nbconvert_exporter": "python", "pygments_lexer": "ipython2", "version": "2.7.9" } }, "nbformat": 4, "nbformat_minor": 0 }