3U]\NáDG%HOND]HVNUDWRZDQLHP
3ROHFHQLH Z\]QDF]\ü UHDNFMH SRGSRURZH GOD SRQL*V]HM EHONL ]H VNUDWRZDQLHP REFL*RQHM
REFL*HQLHPFLJá\PRVWDá\PQDW *HQLX
q.
Przyjmujemy oznaczenia podpór: A i B
1DWRPLDVW SRáF]HQLD SU]HJXERZH R]QDF]DP\
cyframi: 1, 2, 3 i 4.
5R]ZL]DQLH ]DGDQLD UR]SRF]\QDP\ RG XZROQLHQLD XNáDGX RG ZL ]yZ ]DVW SXMF SRGSRU\
UHDNFMDPL*yUQDSRGSRUDR]QDF]RQDOLWHU
A
MHVWSRGSRUWHOHVNRSRZ=DWHPZSXQNFLH
A
G]LDáDUHDNFMDSR]LRPD
R
A
SURVWRSDGáDGRNLHUXQNXPR*OLZHJRSU]HVXZXRUD]PRPHQW
M
A
.
'ROQD SRGSRUD R]QDF]RQD OLWHU
B
MHVW SRGSRU SU]HJXERZ QLHSU]HVXZQ : SXQNFLH
B
Z\VW SXMGZLHQLH]DOH*QHRGVLHELHVNáDGRZHUHDNFMLSLRQRZD
V
B
i pozioma H
B
2EFL*HQLH
FLJáHRVWDá\PQDW *HQLX
q
]DVW SXMHP\GZLHPDZ\SDGNRZ\PL
W
1
= W
2
= q
Â
l = 2 ql.
7U]\UyZQDQLDUyZQRZDJL]DSLVDQHGODFDáHJRXNáDGXQLHZ\VWDUF]GRZ\]QDF]HQLDZDUWRFL
czterech niewiadomych: M
A
, R
A
, V
B
i H
B
-HG\QLHUHDNFM
V
B
PR*HP\Z\]QDF]\ü]UyZQDQLD
l
l
l
2 l
q
l
l
l
l
l
2 l
q
l
l
A
B
1
2
3
4
B
I
4
W
2
l
l
l
l
l
l
l
A
1
2
3
M
A
H
B
R
A
V
B
x
y
W
1
2
U]XWyZVLáQDRSLRQRZGODFDáHJRXNáDGX
0
=
∑
i
iy
P
: V
B
í
q
Â
l = 0
⇒
V
B
= 4 ql
1DVW SQHUyZQDQLHUyZQRZDJL]DSLV]HP\GOD
I
F] FLXNáDGX
=UyZQDQLDPRPHQWyZZ]JO GHPSXQNWX
2
GODF] FL
I
XNáDGXZ\]QDF]\P\ZDUWRüVLá\
S
1
G]LDáDMFHM Z SU FLH
B
í
4
0RPHQW\ RGG]LDá\ZD
V
2
i H
2
Z]JO GHP SXQNWX
2
V UyZQH
]HUX JG\* OLQLH G]LDáDQLD W\FK VLá SU]HFKRG] SU]H] SXQNW
2
=DSLVXMF UyZQDQLH PRPHQWyZ
Z]JO GHPSXQNWX
2
GODF] FL
I
XNáDGXVNRU]\VWDP\]WZLHUG]HQLD9DULJQRQD:W\PFHOX
]DVW SXMHP\VLá
S
1
MHMVNáDGRZ\PLSLRQRZLSR]LRP
5yZQDQLHPRPHQWyZZ]JO GHPSXQNWX
2
GODF] FL
I
XNáDGXPDSRVWDü
∑
=
i
I
i2
M
0 :
í
S
1
ÂFRV.
Â
l
í
W
2
Â
l = 0
⇒
S
1
=
í
3
10
2
ql
.ROHMQHUyZQDQLH]DSLV]HP\GODZ ]áDSRGSRURZHJR
B.
B
4
2
3
H
2
V
2
S
1
ÂVLQ.
I
l
l
l
W
2
S
1
ÂFRV.
sin
.
=
10
1
cos
.
=
10
3
4
B
I
l
l
l
2
3
H
2
V
2
W
2
S
1
l
3 l
.
10 l
.
V
B
H
B
.
S
1
S
2
90
o
sin
=
5
1
cos
=
5
2
2l
l
5 l
3
3U]\MPXMHP\ R SURVWRSDGá GR OLQLL G]LDáDQLD VLá\
S
2
Z\VW SXMFHM Z SU FLH
B
í :
UyZQDQLXU]XWyZVLáQDW R GOD Z ]áD SRGSRURZHJR
B
MHG\Q QLHZLDGRP E G]LH VNáDGRZD
pozioma H
B
: FHOX XSURV]F]HQLD REOLF]HQLD U]XWX VLá\
S
1
QD R ]DVW SXMHP\ VLá
S
1
jej
VNáDGRZ\PLSLRQRZLSR]LRP
=DSLVXMHP\UyZQDQLHU]XWyZVLáQDRGODZ ]áDSRGSRURZHJR
B.
0
=
∑
i
B
i
P
: V
B
ÂVLQ
í
H
B
ÂFRV
í
S
1
ÂFRV.
ÂFRV
+ S
1
ÂVLQ.
ÂVLQ
= 0
⇒
H
B
=
3
11
ql
3R]RVWDáH UHDNFMH Z\]QDF]\P\ ] UyZQD UyZQRZDJL ]DSLVDQ\FK GOD FDáHJR XNáDGX 5HDNFM
SR]LRP
R
A
REOLF]\P\NRU]\VWDMF]UyZQDQLDU]XWyZVLáQDRSR]LRP
0
=
∑
i
ix
P
: R
A
+ H
B
= 0
⇒
R
A
=
í
3
11
ql
Moment podporowy M
A
Z PLHMVFX SRGSRU\ WHOHVNRSRZHM PR*HP\ Z\]QDF]\ü ] UyZQDQLD
PRPHQWyZGODFDáHJRXNáDGXZ]JO GHPSXQNWX
B.
5yZQDQLHWRPDSRVWDü
∑
=
i
iB
M
0 :
í
R
A
Â
l
í
M
A
í
W
Â
l = 0
⇒
M
A
=
í
3
14
ql
2
6SUDZG]HQLH SRSUDZQRFL SU]HSURZDG]RQ\FK REOLF]H Z\NRQDP\ ]DSLVXMF UyZQDQLH
UyZQRZDJL ] NWyUHJR ZF]HQLHM QLH NRU]\VWDOLP\ 0R*H WR E\ü QD SU]\NáDG UyZQDQLH
PRPHQWyZGODFDáHJRXNáDGXZ]JO GHPSXQNWX
C.
0
=
∑
i
iC
M
: H
B
Â
l
í
V
B
Â
l
í
M
A
+ W
Â
l =
3
11
ql
Â
l
í
ql
Â
l
í
(
í
3
14
ql
2
)
+ 4 ql
Â
l =
=
3
22
ql
2
í
ql
2
+
3
14
ql
2
+ 8 ql
2
= 0
5yZQDQLHVSHáQLRQHMHVWWR*VDPRFLRZR
S
2
S
1
ÂFRV.
S
1
ÂVLQ.
V
B
H
B
.
90
o
sin
=
5
1
cos
=
5
2
2l
l
5 l
4
W = W
1
+ W
2
= 4 ql
l
l
l
l
l
l
l
A
1
2
3
M
A
H
B
=
3
11
ql
R
A
=
í
3
11
ql
V
B
= 4 ql
B
C