{ "metadata": { "name": "", "signature": "sha256:d708156611ec89eae1db1c06f5ba02ec9d179b4f495d97ecac600c0bd4aa5921" }, "nbformat": 3, "nbformat_minor": 0, "worksheets": [ { "cells": [ { "cell_type": "heading", "level": 1, "metadata": {}, "source": [ "Chapter 16 : Columns" ] }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 16.1 Page No : 417" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math \n", "\t\t\t\n", "# Variables\n", "E = 10.*10**6 \t\t\t#psi\n", "ys = 6000. \t\t\t#psi\n", "\t\t\t\n", "# Calculations\n", "lbyr = math.sqrt(math.pi**2*E/ys)\n", "\t\t\t\n", "# Results\n", "print 'Slenderness Ratio = %.f '%(lbyr)\n", "\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Slenderness Ratio = 128 \n" ] } ], "prompt_number": 1 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 16.2 Page No : 417" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math \n", "\t\t\t\n", "# Variables\n", "fs = 3.\n", "W = 50. \t\t\t#kips\n", "l = 20. \t\t\t#ft\n", "E = 30.*10**6 \t\t\t#psi\n", "\t\t\t\n", "# Calculations\n", "Pcr = fs*W\n", "I = Pcr*10**3*(l*12)**2/(math.pi**2*E)\n", "r = 2.01\n", "lbyr = l*12/r\n", "\t\t\t\n", "# Results\n", "print 'Required I = %.1f in**4'%(I)\n", "print 'slenderness ratio =%.f '%(lbyr)\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Required I = 29.2 in**4\n", "slenderness ratio =119 \n" ] } ], "prompt_number": 3 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 16.3 Page No : 418" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math \n", "\n", "\t\t\t\n", "# Variables\n", "L1 = 18. \t\t\t#ft\n", "L2 = 9. \t\t\t#ft\n", "I1 = 12.1 \t\t\t#in**4\n", "I2 = 1.2 \t\t\t#in**4\n", "E = 30.*10**6 \t\t\t#psi\n", "\t\t\t\n", "# Calculations\n", "r1 = 2.05\n", "lbyr = L1*12/r1\n", "r2 = 0.65\n", "lbyr2 = L2*12/r2\n", "Pcr1 = math.pi**2*E*I1/(L1*12)**2\n", "Pcr2 = math.pi**2*E*I2/(L2*12)**2\n", "P = Pcr1/2.5\n", "P2 = Pcr2/2.5\n", "\t\t\t\n", "# Results\n", "print 'Design load of 1 = %.2f lb'%(round(P,-2))\n", "print 'Design load of 2 =%.2f lb'%(round(P2,-2))\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Design load of 1 = 30700.00 lb\n", "Design load of 2 =12200.00 lb\n" ] } ], "prompt_number": 5 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 16.4 Page No : 419" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math \n", "\t\t\t\n", "# Variables\n", "E = 30.*10**6\n", "syp = 30000. \t\t\t#psi\n", "I = 143.5 \t\t\t#in**4\n", "A = 7.32 \t\t\t#in\n", "\t\t\t\n", "# Calculations\n", "I1 = 2*I\n", "A1 = 2*A\n", "L = math.sqrt(2*math.pi**2*E*I1/(syp*A1))\n", "\t\t\t\n", "# Results\n", "print 'Critical length of the column = %.0f in'%(L)\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Critical length of the column = 622 in\n" ] } ], "prompt_number": 1 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 16.5 Page No : 421" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math \n", "\t\t\t\n", "# Variables\n", "x = 30. \t\t\t#in\n", "x1 = 10. \t\t\t#in\n", "E = 30.*10**6\n", "d = 0.5 \t\t\t#in\n", "syp = 60000. \t\t\t#psi\n", "y1 = 8. \t\t\t#in\n", "y2 = 2. \t\t\t#in\n", "\t\t\t\n", "# Calculations\n", "ratio = 0.8\n", "l = x+x1\n", "lr = ratio*l\n", "I = (math.pi*(d)**4)/64\n", "Pcr = math.pi**2*E*I/lr**2\n", "scr = Pcr/(math.pi*(d/2)**2)\n", "F = Pcr*y2/(y1+y2)\n", "\t\t\t\n", "# Results\n", "print 'Stress in the critical load = %.0f psi'%(round(scr,-1))\n", "print 'Critical force F =%.0f lb'%(F)\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Stress in the critical load = 4520 psi\n", "Critical force F =177 lb\n" ] } ], "prompt_number": 6 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 16.6 Page No : 423" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math \n", "\t\t\t\n", "# Variables\n", "l = 10. \t\t\t#ft\n", "Ys = 33000. \t\t\t#psi\n", "E = 30.*10**6\n", "A = 13.24 \t\t\t#in**4\n", "\t\t\t\n", "# Calculations\n", "r = 2.\n", "lbyr = l*12/r\n", "Cc = math.sqrt(2*math.pi**2*E/Ys)\n", "fs = 5./3+3*(lbyr)/(8*Cc)+(lbyr)**3/(5*Cc**3)\n", "Sa =((1-((lbyr)**2/(2*Cc**2)))*(Ys))/fs\n", "Pa = Sa*A\n", "\n", "\t\t\t\n", "# Results\n", "print 'Premissible load = %.f kips'%(Pa/1000)\n", "\n", "# note : rounding off error." ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Premissible load = 212 kips\n" ] } ], "prompt_number": 10 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 16.7 Page No : 425" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math \n", "from sympy import Symbol,solve\n", "\t\t\t\n", "# Variables\n", "L = 12. \t\t\t#ft\n", "Po = 100. \t\t\t#kips\n", "e = 2. \t\t\t#ft\n", "ys = 42000. \t\t\t#psi\n", "A = 11.77 \t\t\t#in**2\n", "rmin = 195. \t\t\t#in\n", "Zmin = 11.0 \t\t\t#in**3\n", "lbyr = 74.2\n", "stress = 18. \t\t\t#ksi\n", "\t\t\t\n", "# Calculations\n", "#P = (stress-(Po/A)/((1/A)+((e*12)/Zmin)))\n", "P = Symbol(\"P\")\n", "eq = (((Po+P)/A) + (P*(e*L)/11))/stress - 1\n", "P = solve(eq,P)[0]\n", "\t\t\t\n", "# Results\n", "print 'Additional Load = %.2f kips '%(P)\n", "\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Additional Load = 4.19 kips \n" ] } ], "prompt_number": 1 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 16.8 Page No : 425" ] }, { "cell_type": "code", "collapsed": false, "input": [ "\t\t\t\n", "# Variables\n", "l = 15. \t\t\t#ft\n", "Al = 80. \t\t\t#kips\n", "El = 60. \t\t\t#kips\n", "Ys = 33. \t\t\t#ksi\n", "e = 4. \t\t\t#in\n", "\t\t\t\n", "# Calculations\n", "A = 14.4\n", "rmin = 2.54\n", "Zxx = 54.6\n", "lbyr = l*12/rmin\n", "Smax = ((Al+El)/A)+El*e/Zxx\n", "\t\t\t\n", "# Results\n", "print 'Maximum stress %.1f ksi'%(Smax)\n", "print (\"10 WF 49 is the suitable one\")\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Maximum stress 14.1 ksi\n", "10 WF 49 is the suitable one\n" ] } ], "prompt_number": 12 } ], "metadata": {} } ] }