21Ã×ÌÝÐθÖÎݼܿγÌÉè¼Æ¼ÆËãÊé ÏÂÔØ±¾ÎÄ

¸Ë¼þÃû³Æ ½ØÃæÌØÐÔ ½ØÃæ¹æ¸ñ ¸Ë¼þÌØÐÔ Éè¼Æ²ÎÊý A(cm2) ix(cm) iy(cm) ¼ÆËãÄÚÁ¦ L(mm) ?y ?x 2.26 2.42 2.88 1.94 1.68 1.54 1.96 1.38 1.96 2.23 1.38 1.55 1.75 2.74 6.11 3.59 2.99 2.82 2.60 2.28 2.80 2.08 2.80 1.78 2.08 2.26 2.50 2.18 -591.3 321.4 -168.3 134.9 -113.7 83.4 -65.2 42.5 -26.0 -15.16 -15.16 -15.16 -15.16 -22.74 1507 3000 2656 2656 2942 2942 3201 3201 3466 2100 2382 2679 2976 3273 1 1 1 0.8 0.8 0.8 0.8 0.8 0.8 1 0.8 0.8 0.8 0.8 4 2 1 1 1 1 1 1 1 1 1 1 1 1 ÑÝËã¹ý³Ì ½áÂÛ ?x ?y ?yz ? Ó¦Á¦±È 0.95 0.89 0.89 0.91 0.82 0.89 0.70 0.51 0.40 0.21 0.296 0.30 0.26 0.49 Âú×ã Âú×ã Âú×ã Âú×ã Âú×ã Âú×ã Âú×ã Âú×ã Âú×ã Âú×ã Âú×ã Âú×ã Âú×ã Âú×ã ÉÏÏÒ AH ÏÂÏÒ Ah б¸¹¸Ë aB Bc cD De eF Fg gH Êú¸¹¸Ë Aa Cc Ee Gg Hh

2?110 ??70 ??10 39.4 30.35 2?80??10 23.324 2?63??10 12.286 2?63??5 16.734 2?56??8 7.794 2?50¡Á4 9.956 2?63??4 6.972 2?45¡Á4 9.956 2?63??4 6.972 2?45¡Á4 6.972 2?45¡Á4 5.942 2?50¡Á3 6.686 2?56¡Á3 6.686 2?56¡Á3 66.8 49.3 49.3 0.77 123.97 167.19 ¡ª¡ª ¡ª¡ª 141.28 88.83 89.77 0.340 109.53 94.35 ¡ª¡ª ¡ª¡ª 140.10 113.30 117.12 0.344 152.83 129.09 ¡ª¡ª ¡ª¡ª 130.65 114.31 119.53 0.384 185.57 153.69 ¡ª¡ª ¡ª¡ª 141.47 123.77 ¡ª¡ª ¡ª¡ª 94.16 118.24 121.51 0.429 138.09 114.37 116.82 0.352 138.27 118.72 124.18 0.352 136.05 119.22 126.21 0.361 95.51 149.93 157.20 0.284 11

ËÄ¡¢½ÚµãÉè¼Æ

1¡¢Îݼ¹½Úµã¡°H¡± 1¡¢ÏÂÏҽڵ㡰c¡±

£¨1£©¸¹¸ËÓë½Úµã°åµÄÁ¬½Óº¸·ì £¨a£©¡°Bc¡±¸Ë

¸Ë¼þÖáÁ¦N=240.3kN£¬½ØÃæÎª2L63¡Á5£¬½Úµã°åºñ8mm£¬Ö«±³ºÍÖ«¼âµÄÄÚÁ¦·ÖÅäϵÊý·Ö±ðΪ??0.7¡¢??0.3£¬½Çº¸·ìÇ¿¶ÈÉè¼ÆÖµffw?160N/mm2¡£

Ö«±³º¸·ìº¸½Å³ß´çÈ¡

??hf,min?1.5tmax?1.5?6?3.67mm?? hf,1?4mm??hf,max?1.2tmin?1.2?5?6mm????t=5mmËùÐ躸·ì³¤¶È

l1??N2?0.7hf,1fwf?2hf,10.7?134.9?103??2?4?113.4mm2?0.7?4?160??10hf,1?10?4?40mmÈ¡l1?120mm???62hf,1?62?4?248mmÖ«¼âº¸·ìº¸½Å³ß´çÈ¡

hf,2??hf,min?1.5tmax?1.5?6?3.67mm???4mm??1.2tmin?1.2?5?6mm

??h?t?5mm??f,maxËùÐ躸·ì³¤¶È

l2??N2?0.7hf,2fwf?2hf,20.3?134.9?103??2?4?53.2mm2?0.7?4?160??10hf,2?10?4?40mmÈ¡l2?60mm???62hf,2?62?4?248mm£¨c£©¡°cD¡±¸Ë

¸Ë¼þÖáÁ¦N=-202.5kN£¬½ØÃæÎª2L56¡Á8£¬½Úµã°åºñ8mm£¬Ö«±³ºÍÖ«¼âµÄÄÚÁ¦·ÖÅäϵÊý·Ö±ðΪ??0.7¡¢??0.3£¬½Çº¸·ìÇ¿¶ÈÉè¼ÆÖµffw?160N/mm2¡£

Ö«±³º¸·ìº¸½Å³ß´çÈ¡

??hf,min?1.5tmax?4.2mm??hf,1?5mm??hf,max?1.2tmin?7.2mm

????t-2=6mmËùÐ躸·ì³¤¶È

12

l1??N2?0.7hf,1fwf?2hf,10.7?113.7?103??2?5?81.1mm2?0.7?5?160??10hf,1?10?5?50mmÈ¡l1?90mm???62hf,1?62?5?248mmÖ«¼âº¸·ìº¸½Å³ß´çÈ¡

hf,2??hf,min?1.5tmax?4.2mm???5mm??hf,max?1.2tmin?7.2mm

????t-2=6mmËùÐ躸·ì³¤¶È

l2??N2?0.7hf,2fwf?2hf,20.3?113.7?103??2?5?30.4mm2?0.7?5?160??10hf,2?50mmȡl2?50mm???62hf,2?62?5?310mm

ͼ7 £¨3£©ÏÂÏÒÓë½Úµã°åµÄÁ¬½Óº¸·ì

ÏÂÏÒÓë½Úµã°åµÄÁ¬½Óº¸·ì³¤¶Èl?300mm£¬ËùÊܵÄÁ¦Îª×óÓÒÁ½ÏÂÏҸ˵ÄÄÚÁ¦²î¦¤N=388.8-153.9=234.9KN¡£ÏÂÏҸ˽ØÃæÎª2?80?10£¬½Úµã°åºñ8mm£¬Ö«¼âÓëÖ«±³µÄº¸½Å³ß´ç¶¼È¡

hf?5mm?hf,min?1.5tmax?1.5?10?4.7mm

º¸·ì¼ÆË㳤¶È

13

lw?l?2hf?300?2?5?290mm?60hf?60?5?300mmlw?29

£¬È¡

ÊÜÁ¦½Ï´óµÄÖ«±³´¦µÄº¸·ìÓ¦Á¦Îª

0.7?131.9?103?f???45.5N/mm2?ffw?160N/mm2£¬Âú×ã

2?0.7hflw2?0.7?5?290??N2£®ÉÏÏҽڵ㡰D¡±

£¨1£©¸¹¸ËÓë½Úµã°åµÄÁ¬½Óº¸·ì £¨a£©¡°cD¡±¸Ë

¡°cD¡±¸ËÓë½Úµã°åµÄº¸·ì³ß´çºÍ½Úµã¡°c¡±Ïàͬ¡£ £¨b£©¡°De¡±¸Ë

¸Ë¼þÖáÁ¦N=148.5KN£¬½ØÃæÎª2?50?4£¬½Úµã°åºñ6mm£¬Ö«±³ºÍÖ«¼âµÄÄÚÁ¦·ÖÅäϵÊý·Ö±ðΪ??0.7¡¢??0.3£¬½Çº¸·ìÇ¿¶ÈÉè¼ÆÖµffw?160N/mm2¡£

Ö«±³º¸·ìº¸½Å³ß´çÈ¡

??hf,min?1.5tmax?1.5?6?3.7mm??hf,1?4mm??hf,max?1.2tmin?1.2?4?4.8mm

????t=4mmËùÐ躸·ì³¤¶È

l1??N2?0.7hf,1fwf?2hf,10.7?83.4?103??2?4?73.2mm2?0.7?4?160??10hf,1?10?4?40mmÈ¡l1?80mm???62hf,1?62?4?248mmÖ«¼âº¸·ìº¸½Å³ß´çÈ¡

hf,2?hf,1?4mm

ËùÐ躸·ì³¤¶È

l2??N2?0.7hf,2fwf?2hf,20.3?83.4?103??2?4?36mm 2?0.7?4?160??62hf,2?62?4?248mm?ȡl2?50mm??10hf,2?40mm

???40?2hf,2?48mm£¨2£©½ÚµãÏêͼ

¸ù¾ÝÉÏÊöº¸·ì³¤¶ÈÒÔ¼°¸Ë¼þ½ØÃ棬²¢¿¼ÂǸ˼þÖ®¼äÓ¦Óеļä϶¡¢ÖÆ×÷ºÍ×°ÅäµÈÎó²î£¬°´±ÈÀý»æ³ö½ÚµãÏêͼ£¬Èçͼ8Ëùʾ£¬´Ó¶øÈ·¶¨½Úµã°å³ß´çΪ220mm¡Á190mm¡£

14

ͼ8 £¨3£©ÉÏÏÒÓë½Úµã°åµÄÁ¬½Óº¸·ì

ÉÏÏÒÓë½Úµã°åµÄÁ¬½Óº¸·ì³¤¶Èl?220mm£¬ËùÊܵÄÁ¦Îª×óÓÒÁ½ÉÏÏҸ˵ÄÄÚÁ¦²î¦¤N=467.1-288.9=178.2KN£¬ÒÔ¼°½ÚµãºÉÔØP=27KN¡£ÉÏÏҸ˽ØÃæÎª2?110?70?10£¬½Úµã°åºñ12mm¡£ £¨a£©ÉÏÏÒÖ«±³Óë½Úµã°åµÄ²Ûº¸·ì

ÉÏÏÒÖ«±³Óë½Úµã°åµÄ²Ûº¸·ì³ÐÊܽڵãºÉÔØP£¬²Ûº¸·ì°´Á½Ìõhf?0.5t?3mmµÄ½Çº¸·ì¼ÆËã¡£ÎÝÃæÇã½Ç??arctan?110?£¬½ÚµãºÉÔØPµÄÆ«Ðľàe=30mm¡£

²Ûº¸·ìËùÊܵÄÓ¦Á¦Îª Psin?15.16?103?0.0995?f???1.68Nmm22?0.7hflw2?0.7?3?(220?2?3)?f?Pcos?6Pe?2?0.7hflw2?0.7hfl2w15.16?103?0.9956?15.16?103?202???26.19Nmm2?0.7?3?(220?2?3)2?0.7?3?(220?2?3)22??26.19?222w2?????1.68?21.5Nmm?0.8f?0.8?160?128Nmm,Âú×ã?f?f??1.22??

£¨b£©ÉÏÏÒÖ«¼âÓë½Úµã°åµÄÁ¬½Óº¸·ì

ÉÏÏÒÖ«¼âµÄÁ½Ìõ½Çº¸·ì³Ðµ£Æ«ÐĺÉÔØ?N£¬Æ«Ðľàe=30mm¡£È¡º¸½Å³ß´ç

??f????f2??hf,min?1.5tmax?1.5?10?4.7mm??hf?5mm??hf,max?10?2?8mm

????1.2tmin?7.2Ö«¼âº¸·ìËùÊܵÄÓ¦Á¦Îª

15