結構力學上機實驗

結構力學實驗實驗名稱：平面桁架結構的設計實驗題號：B-33姓名：羅鵬 學號：10111524指導老師：常亮實驗日期：12月3日圖1：結構圖完成結構設計后按如下步驟計算、校核、選取、設計、優(yōu)化二、強度計算軸力和應力建立結構計算模型后，由“求解→內(nèi)力計算”得出結構各桿件的軸力N（見圖3）再由6=N/A得出各桿件應力圖2結構軸力圖（單位：KN）各桿軸力表單位：力(默認),力矩(默認)桿端內(nèi)力值(乘子=1)桿端1桿端2單元碼軸力剪力彎矩軸力剪力彎矩180.0000000-0.000000000.0000000080.0000000-0.00000000-0.000000002140.0000000.00000000-0.00000000140.0000000.000000000.000000003140.000000-0.000000000.00000000140.000000-0.00000000-0.000000004140.000000-0.000000000.00000000140.000000-0.000000000.000000005140.0000000.00000000-0.00000000140.0000000.000000000.00000000680.00000000.00000000-0.0000000080.00000000.000000000.000000007-80.0000000-0.000000000.00000000-80.0000000-0.000000000.000000008-160.000000-0.000000000.00000000-160.000000-0.000000000.000000009-160.0000000.00000000-0.00000000-160.0000000.000000000.0000000010-80.00000000.00000000-0.00000000-80.00000000.000000000.0000000011-100.000000-0.000000000.00000000-100.000000-0.00000000-0.000000001245.0000000-0.000000000.0000000045.0000000-0.00000000-0.00000000130.00000000-0.00000000-0.000000000.00000000-0.000000000.0000000014-30.00000000.00000000-0.00000000-30.00000000.000000000.00000000150.000000000.00000000-0.000000000.000000000.000000000.000000001645.00000000.00000000-0.0000000045.00000000.000000000.0000000017-100.0000000.00000000-0.00000000-100.0000000.000000000.0000000018-75.0000000-0.000000000.00000000-75.0000000-0.00000000-0.000000001925.0000000-0.000000000.0000000025.0000000-0.00000000-0.000000002025.00000000.00000000-0.0000000025.00000000.000000000.0000000021-75.00000000.00000000-0.00000000-75.00000000.000000000.00000000表1各桿件最大軸力表上弦桿下弦桿斜腹桿直腹桿最大軸力值（KN)16014010045三、強度校核根據(jù)6《[6]對于Q235鋼，[6]=215MPa;截面選取方法（請按住CTRL鍵點擊）參考公式：A=0.25π[D2+-（D-2t）2]I=π[D4-(D-2t)4]/64四、截面優(yōu)化控制上弦桿、下弦桿以及腹桿的最大應力，優(yōu)化使這三個最大應力控制在0.9[6].優(yōu)化后得表2桿件19/20/13/14/15桿件1/6/7/10桿件2/3/4/5桿件8/9桿件11/17桿件12/16桿件18/21單位外徑D30.042.070.070.068.038.045.0mm內(nèi)徑d26.035.063.062.063.034.039.0mm壁厚t2.03.53.54.02.52.03.0mm截面面積A175.9423.3731.2829.4514.4226.2395.8mm2慣性矩Ix17329.079083.2405316.1453256.0276283.936756.687728.1mm4剛度EA35185.884665.9146241.0165876.0102887.145238.979168.1KNEI3.515.881.190.755.37.417.5KN.m2Es200.0200.0200.0200.0200.0200.0200.0KN/mm2上弦桿最大軸力N25.080.0140.0160.0100.045.075.0KN應力142.1189.0191.5192.9194.4198.9189.5Mpa外徑D215.0215.0215.0215.0215.0215.0215.0Mpa內(nèi)徑d193.5193.5193.5193.5193.5193.5193.5Mpa上懸桿下懸桿直腹桿斜腹桿初選截面截面D*t（mm）60*468*3.542*268*2.5截面面積（mm2）704709251509最大軸力（Kn）16014045100最大應力（MPa）227.4197.4179.0196.5調(diào)整截面截面型號70*470*3.538*260*3截面面積（mm2）829731226.2514.4最大軸力（KN）16014045100最大應力（MPa）192.9191.5198.9194.4桁架內(nèi)力與應力計算將以上調(diào)整截面數(shù)據(jù)輸入計算表格求得各桿件EA、EI結點,1,0,0結點生成,6,1,1,1,1,2,0結點,8,2,1.5結點生成,4,1,8,8,1,2,0單元,1,2,1,1,0,1,1,0單元生成,5,1,1,1單元,8,9,1,1,0,1,1,0單元生成,3,7,7,1單元,1,8,1,1,0,1,1,0單元,2,8,1,1,0,1,1,0單元生成,4,12,12,1單元,7,12,1,1,0,1,1,0單元,2,9,1,1,0,1,1,0單元,9,4,1,1,0,1,1,0單元,4,11,1,1,0,1,1,0單元,11,6,1,1,0,1,1,0結點支承,1,3,0,0,0結點支承,7,1,0,0結點荷載,8,1,15,270結點荷載,9,1,30,270結點荷載,10,1,30,270結點荷載,11,1,30,270結點荷載,12,1,15,270單元材料性質(zhì),1,1,84665.9,15.8,0,0,-1單元材料性質(zhì),2,5,146241.0,81.1,0,0,-1單元材料性質(zhì),6,7,84665.9,15.8,0,0,-1單元材料性質(zhì),8,9,165876.0,90.7,0,0,-1單元材料性質(zhì),10,10,84665.9,15.8,0,0,-1單元材料性質(zhì),11,11,102887.1,55.3,0,0,-1單元材料性質(zhì),12,12,45238.9,7.4,0,0,-1單元材料性質(zhì),13,15,35185.8,3.5,0,0,-1單元材料性質(zhì),16,16,45238.9,7.4,0,0,-1單元材料性質(zhì),17,17,102887.1,55.3,0,0,-1單元材料性質(zhì),18,18,79168.1,17.5,0,0,-1單元材料性質(zhì),19,20,35185.8,3.5,0,0,-1單元材料性質(zhì),21,21,79168.1,17.5,0,0,-1表3計算所得桿件材料性質(zhì)桿件19/20/13/14/15桿件1/6/7/10桿件2/3/4/5桿件8/9桿件11/17桿件12/16桿件18/21單位剛度EA17329.079083.2405316.1453256.0276283.936756.687728.1mm4EI35185.884665.9146241.0165876.0102887.145238.979168.1KN將所得數(shù)據(jù)輸入求解器五、剛度校核對于桁架，控制跨中撓度最大值不大于撓度的容許值求解得結構撓度圖（圖3）其中[f]=L/200所有位子位移見數(shù)據(jù)（表4）圖3結構位移表4結構撓度位移計算單位：位移(默認),轉(zhuǎn)角(默認)桿端位移值(乘子=1)桿端1桿端2單元碼u-水平位移v-豎直位移θ-轉(zhuǎn)角u-水平位移v-豎直位移θ-轉(zhuǎn)角10.000000000.00000000-0.009129590.00188978-0.01825917-0.0091295920.00188978-0.01825917-0.005812610.00380443-0.02988440-0.0058126130.00380443-0.02988440-0.002766340.00571908-0.03541708-0.0027663440.00571908-0.035417080.002766340.00763372-0.029884400.0027663450.00763372-0.029884400.005812610.00954837-0.018259170.0058126160.00954837-0.018259170.009129590.011438150.000000000.0091295970.00953801-0.01676709-0.006558650.00764823-0.02988440-0.0065586580.00764823-0.02988440-0.003405800.00571908-0.03669600-0.0034058090.00571908-0.036696000.003405800.00378992-0.029884400.00340580100.00378992-0.029884400.006558650.00190014-0.016767090.00655865110.000000000.00000000-0.007654590.00953801-0.01676709-0.00765459120.00188978-0.01825917-0.005098820.00953801-0.01676709-0.00509882130.00380443-0.02988440-0.002562530.00764823-0.02988440-0.00256253140.00571908-0.035417080.000000000.00571908-0.036696000.00000000150.00763372-0.029884400.002562530.00378992-0.029884400.00256253160.00954837-0.018259170.005098820.00190014-0.016767090.00509882170.011438150.000000000.007654590.00190014-0.016767090.00765459180.00188978-0.01825917-0.005102100.00764823-0.02988440-0.00510210190.00764823-0.02988440-0.002233450.00571908-0.03541708-0.00223345200.0057190