GVHD:TS.DNG C HNG

LP XDCTN-K55

Trng i hc M a Cht MN HC

B mn Sc bn vt liu C HC KT CU 2

Bi tp ln s 2

TNH KHUNG SIU TNH BNG PHNG PHP LC

5-2

1)S liu nh sau : STT Kch thc hnh hc Ti trng

L1 L2 q(kN/m) P (kN)M(kN/m)

210840140120

2)S tnh :S 5

yu cu v Th T thc hin

1.Tnh h siu tnh do ti trng tc dng

1.1,v cc biu ni lc:mmen un M lc ct Qlc dc N trn h siu tnh cho.bit F=10J/L(m)

1) Xc nh bc siu tnh v chn h c bn

2)Thnh lp cc phng trnh dng chnh tc dng tng qut

3)Xc nh cc h v s hng t do ca phng trnh chnh tc,kim tra cc kt qu tnh c.

4)Gii h phng trnh chnh tc

5)V biu mmen trn h siu tnh cho do ti trng tc dng M.kim tra cn bng cc nt v iu kin chuyn v.

6)V biu lc ct Q v lc dc N trn h siu tnh cho

1.2.Xc nh chuyn v ngang ca 1 im hoc gc xoay ca tit din K bit

E=2.10kN/m.J=10L(m)

2.Tnh h siu tnh tc dng c 3 nguyn nhn(ti trng,nhit thay i v gi ta di ch).

2.1 Vit h phng trnh chnh tc dng s

2.2 Trnh by 1) V biu M do 3 nguyn nhn ng thi tc dng ln h siu tnh cho v cch kim tra

2)Tnh chuyn v nu nh trn mc 1.2 Bit:

-Nhit thay i trong thanh xin : th trn T=+45,th di l T=+30

-Tnh thanh xin c chiu cao tit din h=0.12(m)

-H s gin n di v nhit =10

-Chuyn v gi ta:

Gi D dch chuyn sang phi mt on =0,001 L (m)

Gi H b ln xung mt on =0,001 L (m)BI LM1.Tnh h siu tnh do ti trng tc dng

1.1,V cc biu ni lc:mmen un M lc ct Qlc dc N trn h siu tnh cho.bit F=10J/L(m):1. Xc nh bc siu tnh v chn h c bna)Xc inh bc siu tnh:

+iu kin cn:

n=T+2K+C+3H-3D (*)vi (K=1,H=5,C=4,D=6,T=0) thay vo cng thc (*) ta c n=0+2.1+4+3.5-3.6=3

+iu kin

Coi (II) l tri t v coi n l 1 ming cng c ni vi ming cng 1 bng 1 khp

m v thanh nf h bt bin hnhVy h cho l h siu tnh bc 3 b)Chn h c bn

2)Thnh lp cc phng trnh chnh tc dng tng qut

(11X1 + (12X2 + (13X3 + (1P = 0

(21X1 + (22X2 + (23X3 + (2P = 0

(31X1 + (32X2 + (33X3 + (3P = 0

3. Xc nh cc h s v s hng t do ca h phng trnh chnh tc,kim tra cc kt qu tnh ton Cc biu mmen un ln lt do X1 = 1; X2 = 1; X3 = 1 v ti trng gy ra trong h c bn nh trn:

Kim tra cc kt qu tnh ton

-Kim tra hang i:

+Hng 1

(NG)

+Hng 2

(NG)+Hng 3

(NG) Kim tra cc h s ca n :

(NG) Kim tra cc s hng t do ca phng trnh chnh tc

(NG)4) Gii h phng trnh chnh tc

H tnh nh tng ng :

5)V biu momen Mp trn h siu tnh cho do tai trng tc dng.Kim

tra cn bng cc nt v kim tra iu kin chuyn v.

Kim tra cn bng cc nt-Kim tra nt K:

-Kim tra nt A -Kim tra nt C: Nt C=0-Kim tra nt C:

Kim tra bng iu kin chuyn v

EMBED Equation.DSMT4

Ta thy cc chuyn v cc gi ta rt nh v ph hp vi yu cu tnh ton c chuyn chuyn v nh trn l do sai s khi tnh ton.6)V biu lc ct QP v lc dc NP trn h siu tnh cho.

1,2)Xc nh chuyn v ngang ti mt ct I(trng tm)hoc gc xoay ca mt

ct ti K.Bit E=2.108 kN/m2 ,J=10-6 L41 (m4)

Vy mt ct K xoay cng chiu kim ng h 1 gc

2.Tnh h siu tnh chu tc dng ca c 3 nguyn nhn (Ti trng ,nhit

Thay i v chuyn v gi ta )

2.1 Vit h phng trnh chnh tc.

2.2 Th t thc hin1.V biu momen un M do c 3 nguyn nhn ng thi tc dng trn h siu tnh cho v kim tra kt qu :

-Cc h s v s hng t do bit:

Tnh cc h s do tc ng ca thay i nhit

Biu lc dc Ni

(NG) Tnh cc h s do chuyn v cng bc gy ra

-i vi lc X1=1

i vi lc X2=1

i vi lc X3=1

Thay tt c cc h s v s hng t do vo phng trnh chnh tcTa c :

Gii h ta c:

H tnh nh tng ng do tc dng ca 3 nguyn nhn gy ra(ti trng,nhit thay i v chuyn v cng bc)

Biu mmen un M do c 3 nguyn nhn gy ra

Tch nt kim tra:

Nt B mmen =0

Kim tra iu kin chuyn v

Tnh chuyn v gc xoay

Vy mt ct K xoay ngc chiu vi chiu kim ng h 1 gc :

SV:Nguyn Vn Qunh MSSV:1021050081

_1297433731.unknown

_1425757614.unknown

_1425836889.unknown

_1425906868.unknown

_1426016987.unknown

_1426283758.unknown

_1426283782.unknown

_1426284003.unknown

_1426149070.unknown

_1426282727.unknown

_1426017998.unknown

_1426149069.unknown

_1425992889.unknown

_1426013434.unknown

_1426014076.unknown

_1426016608.unknown

_1426013744.unknown

_1425997617.unknown

_1425998354.unknown

_1425994828.unknown

_1425991126.unknown

_1425992826.unknown

_1425907445.unknown

_1425906970.unknown

_1425845257.unknown

_1425846828.unknown

_1425906848.unknown

_1425846640.unknown

_1425844330.unknown

_1425844845.unknown

_1425837616.unknown

_1425759115.unknown

_1425759711.unknown

_1425836314.unknown

_1425759576.unknown

_1425758072.unknown

_1425758746.unknown

_1425757959.unknown

_1425755597.unknown

_1425756239.unknown

_1425757237.unknown

_1425757501.unknown

_1425756989.unknown

_1425755761.unknown

_1425756020.unknown

_1425755626.unknown

_1297433831.unknown

_1297519579.unknown

_1425755557.unknown

_1425755155.unknown

_1297519436.unknown

_1297433786.unknown

_1297433810.unknown

_1297433746.unknown

_1297433510.unknown

_1297433608.unknown

_1297433656.unknown

_1297433675.unknown

_1297433635.unknown

_1297433543.unknown

_1297433582.unknown

_1297433527.unknown

_1297433238.unknown

_1297433409.unknown

_1297433456.unknown

_1297433248.unknown

_1297433275.unknown

_1297433122.unknown

_1297433145.unknown

_1297315473.unknown

_1297106377.unknown