½á¹¹Á¦Ñ§Á·Ï°Ìâ¼°´ð°¸1

·¢²¼Ê±¼ä : ÐÇÆÚÈý ÎÄÕ½ṹÁ¦Ñ§Á·Ï°Ìâ¼°´ð°¸1¸üÐÂÍê±Ï¿ªÊ¼ÔĶÁ

½á¹¹Á¦Ñ§Ï°Ìâ¼°´ð°¸

Ò»£® ÊÇ·ÇÌ⣨½«ÅжϽá¹ûÌîÈëÀ¨»¡£ºÒÔO±íʾÕýÈ·£¬X±íʾ´íÎ󣩣¨±¾´óÌâ

·Ö4СÌ⣬¹²11·Ö£© 1 . (±¾Ð¡Ìâ 3·Ö)

ͼʾ½á¹¹ÖÐDE¸ËµÄÖáÁ¦FNDE =FP/3¡££¨ £©.

FP D E a a a a

2 . (±¾Ð¡Ìâ 4·Ö)

ÓÃÁ¦·¨½â³¬¾²¶¨½á¹¹Ê±£¬Ö»ÄܲÉÓöàÓàÔ¼ÊøÁ¦×÷Ϊ»ù±¾Î´ÖªÁ¿¡£ £¨ £©

3 . (±¾Ð¡Ìâ 2·Ö)

Á¦¾Ø·ÖÅäÖеĴ«µÝϵÊýµÈÓÚ´«µÝÍä¾ØÓë·ÖÅäÍä¾ØÖ®±È£¬ËüÓëÍâÒòÎ޹ء££¨ £©

4 . (±¾Ð¡Ìâ 2·Ö)

ÓÃλÒÆ·¨½â³¬¾²¶¨½á¹¹Ê±£¬»ù±¾½á¹¹³¬¾²¶¨´ÎÊýÒ»¶¨±ÈÔ­½á¹¹¸ß¡£ £¨ £©

¶þ£® Ñ¡ÔñÌ⣨½«Ñ¡Öд𰸵Ä×ÖĸÌîÈëÀ¨»¡ÄÚ£©£¨±¾´óÌâ·Ö5СÌ⣬¹²21·Ö£© 1 £¨±¾Ð¡Ìâ6·Ö£©

ͼʾ½á¹¹EI=³£Êý£¬½ØÃæAÓÒ²àµÄÍä¾ØΪ£º£¨ £© A£®M/2£» B£®M£» C£®0£» D. M/(2EI)¡£

Fp/2 Fp Fp/2 A 2a 2. £¨±¾Ð¡Ìâ4·Ö£©

ͼʾèì¼ÜÏÂÏÒ³ÐÔØ£¬ÏÂÃæ»­³öµÄ¸Ë¼þÄÚÁ¦Ó°ÏìÏߣ¬´Ë¸Ë¼þÊÇ£º£¨ £© £Á.ch; B.ci; C.dj; D.cj.

a f g h i 1 j Fp/2

Fp M Fp/2 a a a a 2a

b c d e l k FP=1

3. (±¾Ð¡Ìâ 4·Ö)

ͼa½á¹¹µÄ×îºóÍä¾ØͼΪ£º

M EI 3M/4 M/4 3M/4 M/4 3M/4 lEI lM/4 M/8 M/2 A. ͼb; B. ͼc; C. ͼd; D.¶¼²»¶Ô¡££¨ £©

( a) (b) (c) (d)

4. (±¾Ð¡Ìâ 4·Ö)

ÓÃͼ³Ë·¨ÇóλÒƵıØÒªÌõ¼þÖ®Ò»ÊÇ£º A.µ¥Î»ºÉÔØϵÄÍä¾ØͼΪһֱÏߣ» B.½á¹¹¿É·ÖΪµÈ½ØÃæÖ±¸Ë¶Î£» C.ËùÓи˼þEIΪ³£ÊýÇÒÏàͬ£» D.½á¹¹±ØÐëÊǾ²¶¨µÄ¡£ ( ) 5. £¨±¾Ð¡Ìâ3·Ö£©

ͼʾÁºAµãµÄÊúÏòλÒÆΪ£¨ÏòÏÂΪÕý£©£º( )

£Á£®FPl3/(24EI); B. FPl3/(!6EI); C. 5FPl3/(96EI); D. 5FPl3/(48EI).

FP

2EI A l/2 l/2

Èý£¨±¾´óÌâ 5·Ö£©¶ÔͼʾÌåϵ½øÐм¸ºÎ×é³É·ÖÎö¡£

ËÄ£¨±¾´óÌâ 9·Ö£©Í¼Ê¾½á¹¹BÖ§×ùϳÁ4 mm£¬¸÷¸ËEI=2.0¡Á105 kN¡¤m2£¬ÓÃÁ¦·¨¼ÆËã²¢×÷Mͼ¡£

EI

4 m

B 6 m

¡÷=4 mm

Î壨±¾´óÌâ 11·Ö£© ÓÃÁ¦¾Ø·ÖÅä·¨¼ÆËãͼʾ½á¹¹£¬²¢×÷Mͼ¡£EI=³£Êý¡£

FP FP

l2

lllll2

Áù£¨±¾´óÌâ14·Ö£©ÒÑ֪ͼʾ½á¹¹£¬EI?2.1?104 kN?m2,q?10 kN/mÇóBµãµÄˮƽλÒÆ¡£

B 2EI q 2EI EI 2EI 4 m 2 m 4 m

Æߣ¨±¾´óÌâ 14·Ö£©ÓÃλÒÆ·¨×÷ͼʾ½á¹¹Mͼ£¬¸÷¸ËÏ߸նȾùΪi£¬¸÷¸Ë³¤Îªl ¡£

ÁªÏµºÏͬ·¶ÎÄ¿Í·þ£ºxxxxx#qq.com(#Ì滻Ϊ@)