工程力學(xué)(靜力學(xué))3工程構(gòu)件的靜力學(xué)平衡問題

1、TSINGHUA UNIVERSITY 范欽珊教育教學(xué)工作室 FAN Qin-ShanFAN Qin-Shan s Education & Teaching Studios Education & Teaching Studio 返回總目錄返回總目錄返回總目錄返回總目錄TSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITY TSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYCFR2FR1TSINGHUA UNIVERS

2、ITYFP1FP2FP3M1q(x)xFP6FP5FP4dxM2FP1FP2FP3M1q(x)xTSINGHUA UNIVERSITYFP1FP2FP3M1q(x)xFP6FP5FP4dxM2dxq(x)FQ(x)M(x)TSINGHUA UNIVERSITYTSINGHUA UNIVERSITY返回總目錄返回總目錄TSINGHUA UNIVERSITY返回返回TSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYR10FFnii10FnOOiiMMTSINGHUA UNIVERSITYRRR00

3、0 xixyiyzizFFFFFF000FFFOxOxiOyOyiOzOziMMMMMMTSINGHUA UNIVERSITY0zF 00FFxyMM0FzM0FOMTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITY 0FAM0 xF0yFTSINGHUA UNIVERSITY 0FAM0sin2TWQlFxFlFBQWQPT2sin2FlxFllFxFFB0 xF0cosTBAxFF23cos302QWQWFxlFllFxFFAx0yF0sinTPQBA

4、yFFFF2QWFFlxlFAyTSINGHUA UNIVERSITYQWQWT2sin2FlxFllFxFFBQWQWQWT22sin302sin22FFFFllFlFFBTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITY0 xF0AxF0yF0PFqlFAyqlFAy2 0FAM02PMlFlqlMA225qlMATSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYFPTSINGHUA UN

5、IVERSITYFPFAyFAxFBCTSINGHUA UNIVERSITYFPFAyFAxFBCP2 2BCFFTSINGHUA UNIVERSITYFPFAyFAxFBCTSINGHUA UNIVERSITYFPFAyFAxFBCTSINGHUA UNIVERSITYM=FP lTSINGHUA UNIVERSITYFAxFByFBxFAyM=FP lFBy FBx FCx FCy M=FP lTSINGHUA UNIVERSITYFAxFByFBxFAy考察考察ABD桿桿 的平衡的平衡 MB ( F ) = 0 : MA ( F ) = 0 :FBy= 0FAy= 0Fx = 0 : F

6、Bx+ FAx=0 FBx= -FAxTSINGHUA UNIVERSITYM=FP lFBy FBx FCx FCy 考察考察BC桿桿 的平衡的平衡Fx = 0 : FBx - FCx =0 FCx = FBx = FBxFy = 0 : FBy - FCy =0 FCy = FBy =FBy=0 MB ( F ) = 0 : FCx l+M = 0FCx = FBx = -FPTSINGHUA UNIVERSITYM=FP lFPM=FP lFPFPFPTSINGHUA UNIVERSITYFAxFAyFAxFAyM=FP lM=FP lTSINGHUA UNIVERSITYFPTSING

7、HUA UNIVERSITYFPFCyFAFCxTSINGHUA UNIVERSITYFPFCyFAFCx ME ( F ) = 0 : MA ( F ) = 0 : MC ( F ) = 0 :FCx l -FP 2l = 0-FA l - FP 2l = 0-FCy 2l -FA l = 0ETSINGHUA UNIVERSITYM=FP lTSINGHUA UNIVERSITYM=FP lFAFCTSINGHUA UNIVERSITYM=FP lFAFC MC(F) = 0 : FA= FC = FPFAl +M=0TSINGHUA UNIVERSITY返回返回TSINGHUA UNIV

8、ERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITY : : FPTSINGHUA UNIVERSITYFDEFByFBxTSINGHUA UNIVERSITY FP FPFPTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSIN

9、GHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITY0 xF0AxFTSINGHUA UNIVERSITYTSINGHUA UNIVERSITY0FBMR202ClFlMqlR24CMqlFlTSINGHUA UNIVERSITY 0yFR20AyCFqlF 0AMR2240ACMqllMFlR24CMqlFllMqlFAy247MqlMA23TSINGHUA UNIVERSITYTSINGHUA UNIVERSITY返回返回T

10、SINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERS

11、ITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYFF max = fs FNFFd；FF max；TSINGHUA UNIVERSITYNsmaxFfFmax0FF TSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYmaxFF maxFF TSINGHUA UNIVERSITYWP0sin30cos300 xFFFF F153.6 N TSINGHUA UNIVERSITY213.2NN106620Nsmax.FfFmaxFF NWP0cos30sin300y

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13、ATSINGHUA UNIVERSITY 0sincos20N，lFlWMBAF00NWFFAy00NBAxFFFAAFfFNsTSINGHUA UNIVERSITYN0cossin02FABlMWFl ，00NWFFAy00NBAxFFFAAFfFNss2arccotfs2arccotfTSINGHUA UNIVERSITY返回返回TSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSIT

14、YTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYWyW xWTSINGHUA UNIVERSITYWyW x坡度很小時，剛性塊不滑動坡度很小時，剛性塊不滑動TSINGHUA UNIVERSITYWyW x坡度增加到一定數(shù)值以后，剛性塊滑動坡度增加到一定數(shù)值以后，剛性塊滑動TSINGHUA UNIVERSITYWyW x坡度增加到一定數(shù)值時，剛性塊處于臨界狀態(tài)坡度增加到一定數(shù)值時，剛性塊處于臨界狀態(tài)TSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYCBAllFPFAFBTSINGHUA UNIVERSITYCBAllFPFAFBTSINGH