工程力学(静力学)3工程构件的静力学平衡问题

1、TSINGHUA UNIVERSITY 范钦珊教育教学工作室 FAN Qin-ShanFAN Qin-Shan s Education & Teaching Studios Education & Teaching Studio 返回总目录返回总目录返回总目录返回总目录TSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITY TSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYCFR2FR1TSINGHUA UNIVERSITYFP1FP

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6、=0 FBx= -FAxTSINGHUA UNIVERSITYM=FP lFBy FBx FCx FCy 考察考察BC杆杆 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 UNIVERSITYFPTSINGHUA UNI

7、VERSITYFPFCyFAFCxTSINGHUA 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 UNIVERSITYT

8、SINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITY : : FPTSINGHUA UNIVERSITYFDEFByFBxTSINGHUA UNIVERSITY FP FPFPTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UN

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10、 UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSIN

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13、UA UNIVERSITY 0sincos20N，lFlWMBAF00NWFFAy00NBAxFFFAAFfFNsTSINGHUA UNIVERSITYN0cossin02FABlMWFl ，00NWFFAy00NBAxFFFAAFfFNss2arccotfs2arccotfTSINGHUA UNIVERSITY返回返回TSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYWyW xWTSINGHUA UNIVERSITYWyW x坡度很小时，刚性块不滑动坡度很小时，刚性块不滑动TSINGHUA UNIVERSITYWyW x坡度增加到一定数值以后，刚性块滑动坡度增加到一定数值以后，刚性块滑动TSINGHUA UNIVERSITYWyW x坡度增加到一定数值时，刚性块处于临界状态坡度增加到一定数值时，刚性块处于临界状态TSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGHUA UNIVERSITYTSINGH