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ÍÐÁº¼ÆËã¼ôÁ¦Í¼(kN) ×î´óÍ侨 Mmax = 1.071 kN¡¤m £» ×î´ó±äÐÎ Vmax = 1.409 mm £» ×î´óÖ§×ùÁ¦ Qmax = 12.491 kN £»

×î´óÓ¦Á¦ ¦Ò= 1070796.283/10400 = 102.961 N/mm2£» ÍÐÁºµÄ¿¹Ñ¹Ç¿¶ÈÉè¼ÆÖµ [f]=205 N/mm2£»

ÍÐÁºµÄ×î´óÓ¦Á¦¼ÆËãÖµ 102.961 N/mm2 СÓÚ ÍÐÁºµÄ¿¹Ñ¹Ç¿¶ÈÉè¼ÆÖµ 205 N/mm2,Âú×ãÒªÇó!

ÍÐÁºµÄ×î´óÄÓ¶ÈΪ 1.409mm СÓÚ 1000/150Óë10 mm,Âú×ãÒªÇó! 6¡¢Ä£°åÖ§¼ÜÁ¢¸ËºÉÔØÉè¼ÆÖµ(ÖáÁ¦): ×÷ÓÃÓÚÄ£°åÖ§¼ÜµÄºÉÔØ°üÀ¨¾²ºÉÔØºÍ»îºÉÔØ¡£ 1.¾²ºÉÔØ±ê×¼Öµ°üÀ¨ÒÔÏÂÄÚÈÝ£º (1)½ÅÊּܵÄ×ÔÖØ(kN)£º NG1 = 0.138¡Á6.17 = 0.851 kN£»

¸Ö¹ÜµÄ×ÔÖØ¼ÆËã²ÎÕÕ¡¶¿Û¼þʽ¹æ·¶¡·¸½Â¼A¡£ (2)Ä£°åµÄ×ÔÖØ(kN)£º NG2 = 0.35¡Á1¡Á1 = 0.35 kN£» (3)¸Ö½î»ìÄýÍÁÂ¥°å×ÔÖØ(kN)£º NG3 = 25¡Á0.25¡Á1¡Á1 = 6.25 kN£»

¾­¼ÆËãµÃµ½£¬¾²ºÉÔØ±ê×¼Öµ NG = NG1+NG2+NG3 = 7.45 kN£» 2.»îºÉÔØÎªÊ©¹¤ºÉÔØ±ê×¼ÖµÓëÕñµ¹»ìÄýÍÁʱ²úÉúµÄºÉÔØ¡£ ¾­¼ÆËãµÃµ½£¬»îºÉÔØ±ê×¼Öµ NQ = (2.5+2 ) ¡Á1¡Á1 = 4.5 kN£» 3.²»¿¼ÂÇ·çºÉÔØÊ±,Á¢¸ËµÄÖáÏòѹÁ¦Éè¼ÆÖµ¼ÆËã N = 1.2NG + 1.4NQ = 15.242kN£» 6¡¢Á¢¸ËµÄÎȶ¨ÐÔ¼ÆËã: Á¢¸ËµÄÎȶ¨ÐÔ¼ÆË㹫ʽ: ¦Ò =N/(¦ÔA)¡Ü[f]

ÆäÖÐ N ---- Á¢¸ËµÄÖáÐÄѹÁ¦Éè¼ÆÖµ(kN) £ºN = 15.242 kN£» ¦Ô---- ÖáÐÄÊÜѹÁ¢¸ËµÄÎȶ¨ÏµÊý,Óɳ¤Ï¸±È lo/i ²é±íµÃµ½¦Ô=0.489£»

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i ---- ¼ÆËãÁ¢¸ËµÄ½ØÃæ»Ø×ª°ë¾¶(cm) £ºi = 1.59 cm£» A ---- Á¢¸Ë¾»½ØÃæÃæ»ý(cm2)£ºA = 4.24 cm2£» W ---- Á¢¸Ë¾»½ØÃæÄ£Á¿(µÖ¿¹¾Ø)(cm3)£ºW=4.49 cm3£» ¦Ò-------- ¸Ö¹ÜÁ¢¸Ë×î´óÓ¦Á¦¼ÆËãÖµ (N/mm2)£» [f]---- ¸Ö¹ÜÁ¢¸Ë¿¹Ñ¹Ç¿¶ÈÉè¼ÆÖµ £º[f] =205 N/mm2£» L0---- ¼ÆË㳤¶È (m)£» °´ÏÂʽ¼ÆËã:

l0 = h+2a = 1.5+0.1¡Á2 = 1.7 m£»

a ---- Á¢¸ËÉ϶ËÉì³ö¶¥²ãºá¸ËÖÐÐÄÏßÖÁÄ£°åÖ§³ÅµãµÄ³¤¶È£»a = 0.1 m£» l0/i = 1700 / 15.9 = 107 £»

Óɳ¤Ï¸±È Lo/i µÄ½á¹û²é±íµÃµ½ÖáÐÄÊÜѹÁ¢¸ËµÄÎȶ¨ÏµÊý¦Ô= 0.537 £» ¸Ö¹ÜÁ¢¸ËµÄ×î´óÓ¦Á¦¼ÆËãÖµ £»¦Ò=15242/£¨0.537¡Á424£© = 66.942 N/mm2£» ¸Ö¹ÜÁ¢¸ËµÄ×î´óÓ¦Á¦¼ÆËãÖµ ¦Ò= 66.942 N/mm2 СÓÚ ¸Ö¹ÜÁ¢¸ËµÄ¿¹Ñ¹Ç¿¶ÈÉè¼ÆÖµ [f] = 205 N/mm2£¬Âú×ãÒªÇó£¡

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l0 = k1k2(h+2a)= 1.167¡Á1.004¡Á(1.5+0.1¡Á2) = 1.992 m£» k1 -- ¼ÆË㳤¶È¸½¼ÓϵÊý°´ÕÕ±í1ȡֵ1.167£»

k2 -- ¼ÆË㳤¶È¸½¼ÓϵÊý£¬h+2a = 1.7 °´ÕÕ±í2ȡֵ1.004 £» Lo/i = 1991.836 / 15.9 = 125 £»

Óɳ¤Ï¸±È Lo/i µÄ½á¹û²é±íµÃµ½ÖáÐÄÊÜѹÁ¢¸ËµÄÎȶ¨ÏµÊý¦Ô= 0.423 £» ¸Ö¹ÜÁ¢¸ËµÄ×î´óÓ¦Á¦¼ÆËãÖµ £»¦Ò=15058.704/£¨0.423¡Á424£© = 83.962 N/mm2£» ¸Ö¹ÜÁ¢¸ËµÄ×î´óÓ¦Á¦¼ÆËãÖµ ¦Ò= 83.962 N/mm2 СÓÚ ¸Ö¹ÜÁ¢¸ËµÄ¿¹Ñ¹Ç¿¶ÈÉè¼ÆÖµ [f] = 205 N/mm2£¬Âú×ãÒªÇó£¡ ËÄ£©¡¢±ê×¼²ãÄ£°åÑéËã

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×î´óÍ侨M=0.1¡Á6.504¡Á3002= 58536 N¡¤mm£»

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Ãæ°åµÄ×î´óÓ¦Á¦¼ÆËãֵΪ 0.903 N/mm2 СÓÚÃæ°åµÄ¿¹ÍäÇ¿¶ÈÉè¼ÆÖµ 13 N/mm2,Âú×ãÒªÇó!

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