Cyclopedia of architecture, carpentry, and building : a general reference work . The ratio I ^r- r for steel columns of practice rarely exceeds 150,and is usually less than 100. Fig. 53 is a combination of Figs. 49, 50, 51 and 52, andrepresents graphically a comparison of the Rankine, straight-line,Euler, parabola-Euler, and broken straight-line formulas for flat-ended mild-steel columns, It well illustrates the fact that ourknowledge of the streng-th of columns is not so exact as that, forexample, of the strength of beams. P-^A50000^. 100 200 300 Fig, 53. 89. Design of Columns. All the preced
Cyclopedia of architecture, carpentry, and building : a general reference work . The ratio I ^r- r for steel columns of practice rarely exceeds 150,and is usually less than 100. Fig. 53 is a combination of Figs. 49, 50, 51 and 52, andrepresents graphically a comparison of the Rankine, straight-line,Euler, parabola-Euler, and broken straight-line formulas for flat-ended mild-steel columns, It well illustrates the fact that ourknowledge of the streng-th of columns is not so exact as that, forexample, of the strength of beams. P-^A50000^. 100 200 300 Fig, 53. 89. Design of Columns. All the preceding examples relat-ing to columns were on either (1) computing the factor of safety 114 STKENGTH OF MATERIALS 105 of a given loaded column, or (2) computing the safe load for agiven column. A more important problem is to design a columnto sustain a given load under given conditions. A complete dis-cussion of this problem is given in a later paper on design. Weshow here merely how to compute the flimensions of the cross-section of the column after the form, of the cross-section has beendecided upon. In only a few cases can the dimensions be computed directly(see example 1 following), but usually, when a column formula isapplied to a certain case, there will be two unknown quantities init, A and /? or d. Such cases can best be solved by trial (seeexamples 2 and 3 below). Ediaiivple. 1. What is the proper size of white pine columnto sustain a load of 80,000 pounds with a factor of safety of 5,when the length of the column is 22
Size: 2706px × 924px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bo, bookcentury1900, booksubjectarchitecture, booksubjectbuilding
