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ÆäÖÐ p ¡ª¡ª Á¢¸Ë»ù´¡µ×ÃæµÄƽ¾ùѹÁ¦ (kN/m2)£¬p = N/A£»p = 6.95 N ¡ª¡ª Éϲ¿½á¹¹´«ÖÁ»ù´¡¶¥ÃæµÄÖáÏòÁ¦Éè¼ÆÖµ (kN)£»N = 10.946 A ¡ª¡ª »ù´¡µ×̾̾»ý (m2)£»A = 1.575 fg ¡ª¡ª µØ»ù³ÐÔØÁ¦Éè¼ÆÖµ (kN/m2)£»fg = 15

µØ»ù³ÐÔØÁ¦Éè¼ÆÖµÓ¦°´ÏÂʽ¼ÆËã fg = kc 3 fgk

ÆäÖÐ kc ¡ª¡ª ½ÅÊּܵػù³ÐÔØÁ¦µ÷ÕûϵÊý£»kc = 1.00 fgk ¡ª¡ª µØ»ù³ÐÔØÁ¦±ê×¼Öµ£»fgk = 15 µØ»ù³ÐÔØÁ¦µÄ¼ÆËãÂú×ãÒªÇó!

8.3 ÐüÌôжÁÏÆ½Ì¨¼ÆËãÊé

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Ðü¹ÒʽжÁÏÆ½Ì¨µÄ¼ÆËã²ÎÕÕÁ¬ÐøÁºµÄ¼ÆËã½øÐС£

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ƽ̨ˮƽ¸ÖÁºµÄÐüÌô³¤¶È3.00m£¬²åÈë½á¹¹Ãª¹Ì³¤¶È0.80m£¬ÐüÌôˮƽ¸ÖÁº¼ä¾à(ƽ̨¿í¶È)3.00m¡£

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ÈÝÐí³ÐÔØÁ¦¾ù²¼ºÉÔØ2.00kN/m2£¬×î´ó¶Ñ·Å²ÄÁϺÉÔØ10.00kN¡£ ½ÅÊÖ°å²ÉÓþŲ㽺ºÏ°å£¬½ÅÊÖ°å×ÔÖØºÉÔØÈ¡0.30kN/m2¡£ À¸¸Ë²ÉÓÃÎå²ã½ººÏ°å£¬À¸¸Ë×ÔÖØºÉÔØÈ¡0.30kN/m¡£

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½¨Ò»Ï³Ì Ê÷Ò»×ù·á±® ´´Ò»Á÷ÐÅÓþ ÍØÒ»·½Êг¡ ÒµÖ÷µÄÐèÒª¾ÍÊÇÎÒÃǵÄ×·Çó

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ÀëÆ½Ì¨2.90m¡£ Ò»¡¢´ÎÁºµÄ¼ÆËã

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½ØÃæ³ß´ç b=63.0mm,h=160.0mm,t=10.0mm 1.ºÉÔØ¼ÆËã

(1)Ãæ°å×ÔÖØ±ê×¼Öµ£º±ê׼ֵΪ0.30kN/m2£» Q1 = 0.3030.75=0.23kN/m (2)×î´óÈÝÐí¾ù²¼ºÉÔØÎª2.00kN/m2£» Q2 = 2.0030.75=1.50kN/m

(3)Ð͸Ö×ÔÖØºÉÔØ Q3=0.17kN/m

¾­¼ÆËãµÃµ½£¬¾ù²¼ºÉÔØ¼ÆËãÖµ q = 1.23(Q1+Q3)+1.43Q2 = 1.23(0.23+0.17)+1.431.50 =

2.57kN/m

¾­¼ÆËãµÃµ½£¬¼¯ÖкÉÔØ¼ÆËãÖµ P = 1.4310.00=14.00kN 2.ÄÚÁ¦¼ÆËã

ÄÚÁ¦°´ÕÕ¼¯ÖкÉÔØPÓë¾ù²¼ºÉÔØq×÷ÓÃϵļòÖ§Áº¼ÆË㣬ÄÚ²à¸ÖË¿Éþ²»¼ÆË㣬¼ÆËã¼òͼÈçÏÂ

×î´óÍ侨MµÄ¼ÆË㹫ʽΪ

2

¾­¼ÆËãµÃµ½£¬×î´óÍ侨¼ÆËãÖµ M = 2.5733.00/8+14.0033.00/4=13.39kN.m

3.¿¹ÍäÇ¿¶È¼ÆËã

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2

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4.ÕûÌåÎȶ¨ÐÔ¼ÆËã[Ö÷´ÎÁºº¸½Ó³ÉÕûÌå´Ë²¿·Ö¿ÉÒÔ²»¼ÆËã]

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b=570310.0363.03235/(3000.03160.03235.0)=0.75

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½ØÃæ³ß´ç b=68.0mm,h=180.0mm,t=10.5mm 1.ºÉÔØ¼ÆËã

(1)À¸¸Ë×ÔÖØ±ê×¼Öµ£º±ê׼ֵΪ0.30kN/m

½¨Ò»Ï³Ì Ê÷Ò»×ù·á±® ´´Ò»Á÷ÐÅÓþ ÍØÒ»·½Êг¡ ÒµÖ÷µÄÐèÒª¾ÍÊÇÎÒÃǵÄ×·Çó

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Q1 = 0.30kN/m

(2)Ð͸Ö×ÔÖØºÉÔØ Q2 = 0.20kN/m

¾­¼ÆËãµÃµ½£¬¾²ºÉÔØ¼ÆËãÖµ q = 1.23(Q1+Q2) = 1.23(0.30+0.20) = 0.60kN/m ¾­¼ÆËãµÃµ½£¬¸÷´ÎÁº¼¯ÖкÉÔØÈ¡´ÎÁºÖ§×ùÁ¦£¬·Ö±ðΪ

P1=((1.230.30+1.432.00)30.3833.00/2+1.230.1733.00/2)=2.08kN P2=((1.230.30+1.432.00)30.7533.00/2+1.230.1733.00/2)=3.86kN

P3=((1.230.30+1.432.00)30.7533.00/2+1.230.1733.00/2)+14.00/2=10.86kN P4=((1.230.30+1.432.00)30.7533.00/2+1.230.1733.00/2)=3.86kN P5=((1.230.30+1.432.00)30.3833.00/2+1.230.1733.00/2)=2.08kN

2.ÄÚÁ¦¼ÆËã

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1 2

ÐüÌôжÁÏÆ½Ì¨Ê¾Òâͼ

2.08kN 3.86kN10.86kN 3.86kN 0.60kN/m2800 2.08kNA 200 800B

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