Æð±ÛʱÁ¦±Û½ÏС£¬ÔÚÑö½Ç¡÷A1B1C Ϊ58¡ãʱ£¬Á¦±Ûh=p£¬ÔÚµõ±ÛÑö½Ç½Ï´óʱ£¬Á¦±Ûh½Ï´ó ±ä·ù¹ý³ÌÖÐÁ¦±Ûh±ä»¯Æ½Ó͸׹¤×÷Ìõ¼þºÃ£¬Ñ¹Á¦²ÎÊý±ä»¯Ð¡£¬Ó͸ײÎÊýÑ¡Ôñ½ÏÒ׺ÏÀí£¬½á¹¹½ô´Õ ¡÷A2B2C »º£¬ÔÚÑö½ÇΪ38¡ãʱ£¬Á¦±Ûh=p Æð±ÛʱÁ¦±Ûh½Ï´ó£¬ÔÚ±äÓ͸׹¤×÷Ìõ¼þ½ÏºÃ£¬½á¹¹½ô´Õ Ó͸׹¤×÷Ìõ¼þ¶ñÁÓ£¬ÓÍ¸×´Õ ¡÷A3B3C ·ù¹ý³ÌÖÐh£¼p£¬ÔÚµõ±ÛÑö²ÎÊýÑ¡Ôñ²»ºÏÀí£¬½á¹¹½ô½Ç½Ï´óʱ£¬Á¦±ÛhС Óбí5.1¿ÉÒÔ¿´³ö£¬Ó͸׽µãA²¼ÖÃÔÚA2A1¶ÎÉÏ£¬¿ÉÒÔʹÓ͸׹¤×÷ѹÁ¦±ä»¯Æ½ÎȶøÇÒ»ú¹¹½ô´Õ£¬ËùÒÔAµãÓ¦¸Ã²¼ÖÃÔÚ¶ÎA2A1ÉÏ£¬ÔÚ?=40¡ã¡«50¡ãʱ£¬Á¦±Ûh=p¡£
3±ä·ù»ú¹¹½ÂµãÈý½ÇÐÎ
µõ±ÛÓëÓ͸׵ĽµãBÒ»°ãλÓÚ
11?11?Lµ½Lµõ±ÛÉÏ£¬¹ÊBC=?L,L?£¬L 32?32?=10 .4m£¬È¡BC =5£¬Ñ¡ÔñºÏÀíµÄ½ÂµãÈý½ÇÐÎÈçͼ5.7£¬È·¶¨±ä·ù½ÂµãÈý½ÇÐμ¸ºÎ
³ß´ç[5]¡£
ͼ5.7±ä·ù»ú¹¹Èý½Âµã¼¸ºÎÈý½ÇÐÎ
4±ä·ùҺѹ¸×µÄ»úеÉè¼Æ
13
ͼ5.8±ä·ùҺѹ¸×¶î¶¨¹¤×÷·ù¶ÈµÄ¸÷²ÎÊýͼ
±ä·ùҺѹ¸×Êܵ½µÄÍÆÁ¦FP£º
F??GBlBcos?P?QlcosACsin?
ʽÖУº?¡ª±ä·ùÖáÏßÓëˮƽÏߵļнǣ» l¡ª¹¤×÷±Û³¤£» GB¡ªµõ±ÛµÄÖØÁ¿£»
lB¡ªµõ±ÛÖØÐĵ½½ÂµãCµÄ¾àÀ룻 ?¡ª±ä·ùҺѹ¸×ÓëACµÄ¼Ð½Ç£» R¡ªÆðÖØ»ú¹¤×÷·ù¶È£» a¡ª½ÂµãCÓë»Ø×ªÖÐÐĵľàÀë¡£
½ÂµãCÓë»Ø×ªÖÐÐĵľàÀëaµÄȡֵ·¶Î§Îª1.5¡«3m[6]£¬´Ëʱ?Q=67¡ã£» ¶î¶¨¹¤×÷·ù¶ÈÏÂÆðÖØÁ¿Q=78400N£»
µõ±ÛÖÊÁ¿µÄȡֵ·¶Î§ÊÇÆðÖØ»ú×ÜÖÊÁ¿£¨10t£©µÄ15%¡«20%£¬ÓÉÓÚ²ÉÓõÄÊÇ×éºÏʽÉìËõ±Û£¬ËùÒÔÈ¡µõ±ÛµÄÖØÁ¿GB=10?103?9.8?15%?14700N£»
¹¤×÷ÉþÀÁ¦Smax=14478.3N£» µõ±Û»ù±¾±Û³¤l=10.4m£» ½ÂµãAµ½CµÄ¾àÀëAC=947mm£»
14
(4-4) ACÓëABµÄ¼Ð½Ç?=62¡ã£»
±ä·ùҺѹ¸××î´ó³¤¶ÈABmax=2800mm£» ±ä·ùҺѹ¸××îС³¤¶ÈABmin=1800mm¡£
½«ÒÔÉϲÎÊý´øÈ빫ʽ£¨5-4£©µÃµ½±ä·ùҺѹ¸×µÄÊܵ½µÄÍÆÁ¦£º
FQ?
Qlcos?Q?GBlBcos?QACsin??4.17?105N
5±ä·ùҺѹ¸×Ö÷Òª¼¸ºÎ²ÎÊýµÄ¼ÆËã
£¨1£©±ä·ùҺѹ¸×ѹÁ¦PNµÄѡȡ
ϵͳµÄ¹¤×÷ѹÁ¦Îª¡÷P=20MPa£¬ÒòΪϵͳÖÐÓÐÒ»¶¨µÄ±³Ñ¹£¬ËùÒÔÑ¡ÔñҺѹ¸×µÄ±»Ñ¹Á¦Îª2MPa£¬¹ÊȡҺѹ¸×µÄ¹¤×÷ѹÁ¦PN=22MPa¡£ £¨2£©±ä·ùҺѹ¸×ÄÚ¾¶DbµÄÈ·¶¨
ÓÉÓÚÆû³µÆðÖØ»úµÄ±ä·ùҺѹ¸×ÊÇÒÔÎÞ¸ËÇ»×÷Ϊ¹¤×÷Ç»µÄ£¬ËùÒÔÓй«Ê½ÈçÏÂ
4?4.17?105Db???155mm
?PN3.14?22?1064FQ²Î¿¼±í5.2Һѹ¸×³ß´çϵÁÐȡҺѹ¸×ÄÚ¾¶Db=160mm¡£
±í5.2Һѹ¸×¾¶³ß´çϵÁУ¨µ¥Î»mm£©£¨Õª×ÔGB2348-80£©
8 63 10 80 12 100 16 125 20 160 25 200 32 250 40 320 50 400 £¨3£©±ä·ùҺѹ¸×»îÈû¸ËÖ±¾¶dµÄ¼ÆËã
ÓÉÓÚ»îÈû¸ËÊܵ½Ñ¹Á¦×÷Óã¬ÇÒPN=22MPa£¾7MPa£¬¹Êd=0.7D=0.7?160mm=112mm¡£²Î¿´Ï±í5.3È¡»îÈû¸ËµÄÖ±¾¶d=125mm¡£
±í5.3»îÈû¸ËÖ±¾¶³ß´çϵÁÐ/mm 4 20 56 160 5 22 63 180 6 25 70 200 8 28 80 220 10 32 90 250 12 36 100 280 14 40 110 320 16 45 125 360 18 50 140 400 £¨4£©»îÈû¸ËÀíÂÛÍÆÁ¦F1ºÍÀÁ¦F2µÄ¼ÆËã
15
ͼ5.9»îÈû¸ËÊÜÁ¦·ÖÎöͼ
»»îÈû¸ËµÄÊÜÁ¦·ÖÎöͼÈçͼ5.9¡£ µ±»îÈû¸ËÉì³öʱÀíÂÛÍÆÁ¦F1£º
F1?A1PN?6.9?105N
µ±»îÈû¸Ë»ØËõʱÀíÂÛÀÁ¦F2
F?AP?6.2?104N
22NʽÖУºA1ºÍA2·Ö±ðΪÎÞ¸ËÇ»ºÍÓиËÇ»µÄÊÜÁ¦Ãæ»ý£» PNΪҺѹ¸×µÄ¹¤×÷ѹÁ¦£¬PN=22MPa¡£ £¨5£©±ä·ùҺѹ¸×»îÈû¸ËÐгÌSµÄÈ·¶¨
ÓÉÓÚҺѹ¸×È«Éìʱ£º
ABmax=2800mm
±ä·ùҺѹ¸×È«Ëõʱ£º
ABmin=1800mm
µÃµ½±ä·ùҺѹ¸×ÐгÌS£º
S=ABmax¡ªABmin=1000mm
²é[3]±í37.7-3ѡȡÐгÌS=1000mm¡£ £¨6£©ÒºÑ¹¸××îСµ¼Ïò³¤¶ÈHµÄÈ·¶¨
µ¼Ïò³¤¶È¹ý¶Ì£¬½«Ê¹¸×ÒòÅäºÏ¼ä϶ÒýÆðµÄ³õʼÄÓ¶ÈÔö´ó£¬Ó°ÏìҺѹµÄ¹¤×÷ÐÔÄܺÍÎȶ¨ÐÔ£¬Òò´Ë£¬Éè¼Æ±ØÐë±£Ö¤¸×ÓÐÒ»¶¨µÄ×îСµ¼Ïò³¤¶È£¬ÒºÑ¹¸×µÄ×îСµ¼Ïò³¤¶ÈÓ¦Âú×ã[2]£º
H?S20?D2 ʽÖУºSÊDZä·ùҺѹ¸×µÄ×î´óÐг̣¬S=1000mm£» DÊDZä·ùҺѹ¸×µÄÄÚ¾¶£¬D=160mm£» ¹ÊÓУº
H?SD100020020?2?20?2?150mm¡£
£¨7£©ÒºÑ¹¸×¸×Ͳ±Úºñ?bµÄ¼ÆËã
²é[3]±í37.7-64¹¤³Ì»úеÓø×Í⾶ϵÁÐÈ¡±ä·ùҺѹ¸×Í⾶Ϊ245mm£¬ÒºÑ¹¸×Ìå²ÄÁÏΪ45ºÅÎÞ·ì¸Ö¹Ü¡£Òò´Ë£¬±ÚºñΪ?b=£¨245¡ª200£©/2=22.5mm¡£ £¨8£©ÒºÑ¹¸×µÄ¸×µ×ºñ¶Èhb¼ÆËã
Éè¼Æ´Ë¸×ΪƽÐи׵ף¬²é[3]µÃ
16
(4-5)