
2022年钢结构原理与设计第2版课后答案.pdf
43页4-1 解:kNNNNQKQGKG420315324.1315312 .1焊缝质量为三级,用引弧板施焊查表得E43 焊条的2/185mmNfWt,Q235 钢的2/215mmNfmmbfNtWt35.11185200104203故取mmt124-2 解:kkkQKQGKGNNNNNN36.18 .04 .12.02 .1焊缝质量为二级,2/215mmNfWt未用引弧板施焊mmlW376122400tlNfWWt,kWWtNtlfN36.1kNtlfNWWtk3 .71336.11237621536.14-4解:1)焊脚尺寸fh背部尺寸mmthmmthff6.982 .12.174.4105.15.1min1max1趾部尺寸mmthmmthff762182174.4105 .15.1min2max2为方便备料,取mmhhhfff621,满足上述要求2)轴心力 N 的设计值kNNNNQKQGKG4.2481809 .04.11801 .02 .1按角钢背与趾部侧面角焊缝内力分配系数可知:等边角钢内力分配系数3.01be7.02be对角钢趾部取力矩平衡得: 21NebNkNNNbeN52.744 .2483.03.021kNNNNN88.1734.2487.07.0123)焊缝长度。
当构件截面为一只角钢时, 考虑角钢与节点板单面连接所引起的偏心影响,Wtf应乘以折减系数0-85角钢趾:mmhmmfhNlfWffW48813016085.067. 01052.7485.07 . 0311取mml1401(mmhf1422130,取 10mm 的整数倍)角钢背:mmhmmfhNlfWffW3606030416085.067. 01088.17385.07. 0322取mml3202(mmhf3162304,取 10mm 的整数)4-5解:腹板受到轴心拉力kN作用kNNNNQKQGKG4 .5984408 .04. 14402 .02 .1焊脚尺寸fhmmthf6 .55. 1max,mmthf98)21(min取mmhf6时,mmhmmfhNlfWffW360602.44516067. 02104 .5987 .023不可行;取mmhf7时,mmlw6 .381,mmhlfw42060可行,mmhlf6 .39526 .381,取mml400取mmhf9时,mmlw8.296,mmhlfw54060可行,mmhlf8.31428 .296,取mml320故最小的焊脚尺寸可取mm7,钢板搭接长度为mm400最大的焊脚尺寸可取mm9,钢板搭接长度为mm3204-7 解:(1)直接计算法mkNNlM102.0502262/1.148862407.0101067. 0mmNhhlhMffWff23/6.2972407. 010507.0mmNhhlhNffWffWfffff221606.29722.11.148822ffhh解得:mmhf85. 7采用mmtmmtmmhf982136.6185.15. 18minmax,可(2)试算法mmtmmthf982136.6185 .15.1minmax取mmhf82134424087 .07 .0mmlhlhAWfWeW3225376024087.06161mmlhWWeW2262/0.186624087.0101067. 0mmNlhMWff23/2 .3724087. 010507 .0mmNlhNWff222222/160/9 .1562.3722.1186mmNfmmNWffff,可故mmhf84-8 解:kNRRRkk405%754.1%252. 1mml300mmlh701080取焊脚尺寸mmhf6mmhhfe2.47. 0(1)几何关系水平焊缝计算长度mmhllfhWh64670全部焊缝计算长度mmlllWhW4286423002全部焊缝有效截面WeWlhA形心位置cmhhAllhxeeWWhWhe96.08.4224.64.6222略去3eh项423236 .21542304 .642.02123042.02212cmllhlhIWheex42232238 .4796.04.642.096.024.64.642.0124 .642.022122cmxlhxllhlhIWheWhWheWhey焊缝有效截面对形心O 的极惯性矩404.22028.476.2154cmIIIyx(2)强度验算kNRV5.2022mmxa4.7080mkNRaT3.142104 .7040523mmxlxWh4.546.9641mmly1502124601/3.35104 .22024 .54103 .14mmNITxTf24601/4.97104.2202150103 .14mmNITyTf23/7 .1124282.4105 .202mmNAVVf剪力和扭矩共同作用下的强度条件222222/160/6.1554.9722.17 .1123 .35mmNfmmNWfTffVfTf,可5-1 解:QKQGKGNNN则:NNk8.772560%904.1560%102 .1查表,得:钢板螺栓孔壁承压承载力设计值:2/405mmNfbc螺栓的强度设计值为:2/190mmNfbv)(32.1191019044002432kNfdnNbvevbv)(1621040520203kNtfdNbcbc取)(32.119,minkNNNNbcbvb需要的螺栓数目:48. 632.1198.772bNNn最少采用7n试取螺栓距mmmmdpo655 .613端距mmmmdao45412边距mmmmdco3575.305.1因为板宽mmb250, 若边距为mm35则不满足间距不大于mmt12012要求,故最外排每列螺栓应设3 个,取螺栓横向间距为mm90,端距为mm45,螺栓数增加为 8 个。
取螺栓纵向间距为mm65,边距为mm35第二列布置 2 个螺栓,符合不大于mmt24024的构造要求已知,在最外侧螺栓处的截面, 钢板受力最大,截面上有 3 个螺栓孔,其净面积为最小,即:21377020)5.203250()3(mmtdbAon净截面平均拉应力为:2231/205/2053770108.772mmNfmmNANn,(1nA为mm20钢板面积,f 应该按照mm20钢板取)可下面再验算拼接板四角处有无块状拉剪破坏的危险则每一块板呗抗剪破坏所需之力为)(9 .2071021510)5 .205. 035(1012510)5.205.265245(331kNN拼缝一侧上、下两块拼接板同时有4 角拉剪破坏时所需轴向力为)(8 .772)(6 .8319.207441kNkNNN因而此处不会发生块状拉剪破坏5-4 解:2/190mmNfbv2/4 0 5 mmNfbc设螺栓单列为 n 个kNPPPkk544%804.1%202. 1mkNPeT682505442121(1)单个螺栓受剪承载力设计值:螺栓杆被剪断承载力:kNfdnNbvvbv2 .721902241422螺栓孔承压破坏承载力:kNftdNbcbc56.1424051622单个螺栓受剪承载力:kNNNNbcbvb2 .72,minmin(2)求每列螺栓的个数n 的值。
取bTNNmin由修正公式( 5-10) :83. 535.6135.670102.722106861636nnpmNTnT取 n=6 (3)强度验算:螺栓除受扭转作用外,还受到竖向的剪力kNyxTyNiiiTxi93.47175105354801217510682222622kNyxTxNiiiTyi91.2117510535480128010682222622kNnPNPy67.222由偏心剪力作用下强度条件:kNNNNNbPyTyiTxi2 .7246.6567.2291.2193.47min2222,可5-5 解:2/140mmNfbv2/1 7 0 mmNfbt2/3 0 5 mmNfbc设螺栓单列为 n 个kNNNk5604.1(1)单个螺栓受剪承载力设计值:螺栓杆被剪断承载力:kNfdnNbvvbv2 .5314022414.31422螺栓孔承压破坏承载力:kNftdNbcbc36.1073051622单个螺栓受剪承载力:kNNNNbcbvb2 .53,minmin(2)单个螺栓受拉承载力kNfANbtebt6 .511704.303(由附表1-4得直径 22mm 的螺栓有效截面积24 .303mm)(3)单个螺栓受剪力和拉力的设计值:kNnnNNNNtNv2140222(4)因为螺栓同时受剪和受拉,需满足:122bttbvvNNNN解得:34.5n取6n5-8 解:查表得:螺栓抗剪强度2/250mmNfbv一个高强度螺栓的设计预拉力值kNP150钢板螺栓孔壁承压承载力设计值2/470mmNfbc抗滑移系数45.0)(5 .12115045.029. 09. 0kNPnNfbv)(44.1651047016223kNtfdNbcbc取)(5.121,minkNNNNbcbvb则93.6705 .121210136663pmNTnT(bvN中传力摩擦面为2,故两边一起算,T 不需除 2)修正41.6)93.6193.6(93. 6) 1(nnnn取7n验算强度:)(3640)21147(48142222222cmyx)(23.393640100216822maxmaxkNyxTyNTx)(8 .293640100813622maxmaxkNyxTxNTy)(86.3872544kNmnPNPy0PxN强度:)(5.121)(26.104)86.388.29(46.78)()(222max2maxkNNkNNNNNbvPyTyPxTx可,每侧所需螺栓数目为7 个。
5-9 解:预拉力值:kNP190螺栓杆被剪断承载力:kNPnNfbv95.7619045. 019.09. 0单个螺栓受拉承载力:kNPNbt1521908 . 08. 0单个螺栓受剪力和拉力的设计值:kNnnNNNNtNv2140222因为螺栓同时受剪和受拉,需满足:1bttbvvNNNN解得:9.3n取4n摩擦型连接无需验算孔壁承压强度6-2 解: 由结点 b 的力的平衡可得 : Ab杆受压力KNF37.121 Cb 杆受拉力KNF37.122需要的构件截面面积:22576.010215100037.12cmfNAAn其中 Ab杆为压杆, Cb为拉杆Cb杆需要的截面回转半径为cmlioxx06.140010023cmlioyy06. 140010023由截面面积和回转半径可选用截面如下: 选用5452供给222576.0584.8292.42cmcmcmAcmcmix06.137.1cmcmiy06. 118. 2A,ix,iy均满足要求,无需验算Ab杆需要的截面回转半径为:cmlioxx12.220010023cmlioyy12.220010023可选4702供给222576.014.1157.52cmcmcmAcmcmix12.218.2cmcmiy12. 214.3对X轴:62.19418.210023xoxil此截面为 B类截面,查表知195.022/215/67.5610014.11195.0100037.12mmNfmmNAN,稳定性符合要求,可。
同理,可得对Y轴:12.13514.310023xoxil此截面为 B类截面,查表知365.022/215/42.3010014.11365.0100037.12mmNmmNAN, 稳定性符合要求,可 )6-5 解:以实轴为 X轴,虚轴为 Y轴,则有:3335.4760812404.36128.4237cmIx3311819212374.1cmIy26.127406.02374.1cmAcmAIixx32.19cmAIiyy62.94.4132.19800 xoxxil6 .4162.9400yoyyil此工字钢截面对 x 轴屈曲为 。
