试求图示梁的自振频率和主振型。[img=396x213]17cfe4ec70149f6.png[/img]
解: 图中为连续梁, 按柔度法求解, 作出 [tex=3.143x1.357]iBs3WIx0YYhxYieXHAlNRYaRx15EQVHO9gfgzve1b2U=[/tex]的图。[img=298x206]17cfe4f629ee866.png[/img]图乘法求得各项柔度系数:[tex=22.286x2.5]yfIcxLB/Y63PKkiikly2YchSipRElWJg2tqtJ5yMcUEu+BSGLS5ddMAAbC0hq0nta07rqTHwNApKtm+Bu3DF46lZsmwbHxUAFUOiOcfrhkkRLI4GIHfv70kfTFE07T2XEWO4Kg0gcwbERBvWOw1OWYF4HbN0fuxY+pyKtCeQfyycMwTkInkmbvbbt6TWjCUB[/tex]代入公式求频率:[tex=35.786x6.214]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[/tex]则 [tex=15.929x2.571]ZQ2wuM5YfG+0NcO7Be54msim2sxvNeptgj1N1kc5SYLUU8xSnChgBZ1tjCRJL7gALicpb++BcXnWTD9jfvOkgeUNlZ6bdQRghQQMLwwFsHC5oWMNeutg6dLG9QB57I8IjijrxxbYmC9WZHkYn6EIFbj2IMahQIBcIADnEDBK/MI=[/tex] 。所以[tex=10.357x6.357]qeiYnKXLEhyhuGRg8yLtrwkVK5vpL2uPwRCpMuYNhUpByRmGNUdaF78R232kNEuCmlPYiYl/fPjUyfKwPdfeeDC0GsgZKupVmKtge/adTzGWOv1grx/mBG5fn7pf+oRf17UYkFpCaQPr1VN6LMNtLxcDKrkzB9zfVNyNU8D+Zh14vQSnDi2ozLkx/Swd/U0SsgMWLkkPl3KP60/uiqL0sdj+oiK3e1QZfATyMXA/d9Ylxj5dPiGG4meQWkZnCWGp[/tex]代入公式求阵型[tex=13.571x6.5]qeiYnKXLEhyhuGRg8yLtr3czeTIoqWRN3qX6vro8AQZTVIX2a50MR5vQmzBm0GQBTrx8H1+bascHxUoNvd0uw0TcNrDoPln/AfDZUEs6QNRsNC3cZlIn3gd19ZaW98Rvi6k/hHabCwtV6GxETz8qq5Usb4IG/CighjeQktdQF8i7CxcAqZ1KkMp19czOQ4j0b57Ey+zy7gzkaXyEG4bthvn8MnhOdjysSMjNlxm6xin14ZTQB+xl7DrvX9AjVl3YOIKT6HaXqLOAdVagSCUVZev2pHT/AcqejqlJT36kK6pw6a9qdVSXFNt9jNm9uEcpqjarHH37ZkI/jTwIMAdwRg==[/tex]
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内容
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试求图示体系的自振频率。[img=316x255]17cfe1cd669cbd9.png[/img]
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试求图示刚架的自振频率及主振型。各杆[tex=1.214x1.0]s9Je1M5xVQ90RVSHJTCpMA==[/tex]均为同一常数。[img=229x249]17a7be6724b2d85.png[/img]
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求图示结构的自振频率=和主振型=。不计自重。
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试求图8-18所示对称体系的自振频率和振型。各杆[tex=4.571x1.286]NSKjTj7psZYdOS6Y0a7ZyA==[/tex]。[img=381x276]17a15b1984c3360.png[/img]
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试求图示体系的第一频率和第一主振型。各杆[tex=1.357x1.286]/iL/B4wMZRZQHTlB2tPOsg==[/tex]相同。[img=246x184]17d17f8e52c5b63.png[/img]