{ "metadata": { "name": "", "signature": "sha256:688a5ddb04d5076a46d59fbb5d6dc8d907dec2ec735786354cef92d935d1ccd0" }, "nbformat": 3, "nbformat_minor": 0, "worksheets": [ { "cells": [ { "cell_type": "heading", "level": 1, "metadata": {}, "source": [ "Chapter 9: Deflections of beams" ] }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 9.17, Page number 654" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "\n", "#Variable declaration\n", "P = 5 #load(k)\n", "L = 8*12 #beam length(in)\n", "E = 30*10**6 #modulus of elasticity(psi)\n", "I = 75.0 #moment of inertia(in^4)\n", "q = 1.5*(1./12.)#load intensity(k/in)\n", "\n", "#Calculations\n", "Sc = ((P*L**3)/(48*E*I))+((5.*q*L**4)/(384.*E*I))\n", "\n", "#Result\n", "print \"The download deflection is\",Sc,\"in(Calculation mistake in textbook)\"\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The download deflection is 0.0001024 in(Calculation mistake in textbook)\n" ] } ], "prompt_number": 8 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 9.23, Page number 682" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\n", "#Variable declaration\n", "E = 30*10**6*144 #modulus of elasticity(lb/ft^2)\n", "I = 25.92/12 #moment of inertia(ft^4)\n", "x = 12 #ft\n", "\n", "#Calculations\n", "'''The equivalent load q(x) for the beam is given by the following equation\n", "q(x) = -700(x)^-1+800(x-6)^0 - 800(x-12)^0 - 5600(x-12)^-1 + 1500(x-16)^-1\n", "Since the equation equals zero at all points except where x=16, we omit the last term\n", "Taking 4th order integration, we obtain the following expression,'''\n", "C1 = (-((350*x**3)/3)+((100*(x-6)**4)/3)-((100*(x-12)**4)/3)+((2800*(x-12)**3)/3))/12\n", "print \"C1 =\",C1\n", "\n", "#For Deflection at point C\n", "x = 6\n", "Elv = ((350*x**3)/3)-(100*((x-6)**4)/3)+(100*((x-12)**4)/3)+(2800*((x-12)**3)/3)+(C1*x)\n", "Sc = Elv/(E*I) #ft\n", "\n", "#For deflection at point D\n", "x = 16\n", "Elv_16 = ((350*x**3)/3)-(100*((x-6)**4)/3)+(100*((x-12)**4)/3)+(2800*((x-12)**3)/3)+(C1*x)\n", "Sd = Elv_16/(E*I)\n", "\n", "#Results\n", "print \"Deflection at point C is\",round((-Sc*12),8),\"in\"\n", "print \"Deflection at point D is\",round((Sd*12),8),\"in\"\n", "\n", "print \"\\n Please note that there is a calculation mistake in textbook while calculating Elv. Hence, the difference in solution\"\n", "\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "C1 = -13200\n", "Deflection at point C is 0.00027315 in\n", "Deflection at point D is 2.06e-06 in\n", "\n", " Please note that there is a calculation mistake in textbook while calculating Elv. Hence, the difference in solution\n" ] } ], "prompt_number": 19 } ], "metadata": {} } ] }