From b1f5c3f8d6671b4331cef1dcebdf63b7a43a3a2b Mon Sep 17 00:00:00 2001 From: priyanka Date: Wed, 24 Jun 2015 15:03:17 +0530 Subject: initial commit / add all books --- 764/CH7/EX7.19.b/graph7_19.png | Bin 0 -> 14660 bytes 764/CH7/EX7.19.b/result7_19.txt | 91 ++++++++++++++++++++++++++++++++++++++ 764/CH7/EX7.19.b/solution7_19.sce | 59 ++++++++++++++++++++++++ 3 files changed, 150 insertions(+) create mode 100755 764/CH7/EX7.19.b/graph7_19.png create mode 100755 764/CH7/EX7.19.b/result7_19.txt create mode 100755 764/CH7/EX7.19.b/solution7_19.sce (limited to '764/CH7/EX7.19.b') diff --git a/764/CH7/EX7.19.b/graph7_19.png b/764/CH7/EX7.19.b/graph7_19.png new file mode 100755 index 000000000..e7b7f8c0b Binary files /dev/null and b/764/CH7/EX7.19.b/graph7_19.png differ diff --git a/764/CH7/EX7.19.b/result7_19.txt b/764/CH7/EX7.19.b/result7_19.txt new file mode 100755 index 000000000..d9a304656 --- /dev/null +++ b/764/CH7/EX7.19.b/result7_19.txt @@ -0,0 +1,91 @@ +-->//(Threaded Joints) Example 7.19 + +-->//Maximum external force Pmax (kN) + +-->Pmax = 10 + Pmax = + + 10. + +-->//Minimum external force Pmin (kN) + +-->Pmin = 0 + Pmin = + + 0. + +-->//Assume the stiffness of the bolts to be 1N/mm kb + +-->kb = 1 + kb = + + 1. + +-->//Calculate the stiffness of the parts kc + +-->kc = 3 * kb + kc = + + 3. + +-->//Overload percentage load (%) + +-->load = 50 + load = + + 50. + +-->//Yield tensile strength of 50C4 Syt (N/mm2) + +-->Syt = 460 + Syt = + + 460. + +-->//Ultimate tensile strength of 50C4 Sut (N/mm2) + +-->Sut = 660 + Sut = + + 660. + +-->//Fatigue stress concentration factor Kf + +-->Kf = 2.2 + Kf = + + 2.2 + +-->//Expected reliability (%) + +-->reliability = 90 + reliability = + + 90. + +-->//Factor of safety fs + +-->fs = 2 + fs = + + 2. + +-->//Assume diameter of the bolt to be less than 7.5mm for Kb to be 1 + +-->d = 1 + d = + + 1. + +-->//As Ka is incorporated into Kf, assume the assembly to be ground + +-->//This is just to obtain a random value of Ka + +-->op = 1 + op = + + 1. + + +Core cross-section area of the bolt(A) = 39.413787 mm2 + \ No newline at end of file diff --git a/764/CH7/EX7.19.b/solution7_19.sce b/764/CH7/EX7.19.b/solution7_19.sce new file mode 100755 index 000000000..bd4260cf2 --- /dev/null +++ b/764/CH7/EX7.19.b/solution7_19.sce @@ -0,0 +1,59 @@ + + +function[] = plot_format() + //Get the handle of current axes + g = gca() + //Give labels and set label properties + g.labels_font_color=5 + g.font_size=3 + g.grid=[1,1] + g.box="off" +endfunction + +//Obtain path of solution file +path = get_absolute_file_path('solution7_19.sce') +//Obtain path of data file +datapath = path + filesep() + 'data7_19.sci' +//Obtain path of function file +funcpath = path + filesep() + 'functions7_19.sci' +//Clear all +clc +//Execute the data file +exec(datapath) +exec(funcpath,[-1]) +//Calculate the endurance limit stress for bolt Sdash (N/mm2) +Sdash = (50/100)*Sut +//Calculate Ka, Kb and Kc +[Ka, Kb, Kc] = fluctuate(op, d, reliability) +//Calculate Kd +Kd = 1/Kf +//Calculate the corrected endurance limit stress Se (N/mm2) +Se = Kb * Kc * Kd * Sdash +//Plot modified Goodman diagram +//The common quadrilateral in the plot is the area of concern +y1 = {Se 0} +x1 = {0 Sut} +y2 = {Syt 0} +x2 = {0 Syt} +plot(x1,y1,'--*') +plot(x2,y2,'-*') +plot_format() +title('Modified Goodman diagram (Example 7.19)') +xlabel('sigmaM (N/mm2)') +ylabel('sigmaA (N/mm2)') +//Calculate the external force at overload condition PbMax (N) +PbMax = (Pmax * 1000) + ((load/100)*Pmax * 1000) +//Calculate the initial pre-load Pi (N) +Pi = PbMax/((kb + kc)/kc) +//Calculate the maximum force in the bolt PMAX (N) +PMAX = Pi + ((kb/(kb + kc))*(Pmax * 1000)) +//Calculate the minimum force in the bolt PMIN (N) +PMIN = Pi + ((kb/(kb + kc))*(Pmin * 1000)) +//Calculate the mean force and force amplitude +Pm = (PMAX + PMIN)/2 +Pa = (PMAX - PMIN)/2 +//Calculate the actual core cross-section area of the bolt A (mm2) +A = (Pa + (Pi/((1 + (Sut/Se)) * fs)))/(Sut/((1 + (Sut/Se))*fs)) +//Choose proper diameter from Table 7.1 +//Print results +printf('\nCore cross-section area of the bolt(A) = %f mm2\n',A) -- cgit