MC LC Li ni u................................
...........................................02 . 1. GII THIU CHUNG
..............................................................................03
1.1. Cng dng, vng hot ng, quy phm p dng
...................................03 1.2. Cc thng s c bn v t s kch
thc ca tu ................................... 03 1.3. La chn h thng
kt cu
....................................................................03
2. KHONG CCH SN V S PHN KHOANG ...........................04 2.1.
Khong cch sn
................................................................................04
2.2. S phn khoang
...............................................................................04
3. TNH CHN KT CU.
..............................................................................05
3.1. Xc nh ti trng
boong........................................................................05
3.1.1. Boong thi
tit.......................................................................05
3.1.2. Boong vung kiu thng tng
lu.................................................07 3.2. Chiu di
tn
bao................................................................................07
3.2.1. Tn
bao................................................................................07
3.2.2. Tn
boong........................................................................08
3.2.3. Tn
vch...................................................................09
3.3. Kt cu khoang
hng...............................................................................09
3.3.1.Vch
ngang................................................................09
3.3.2. Dn
boong.................................................................13
3.3.3. Dn
mn....................................................................16
3.2.4. Dn
y.....................................................................20
3.4. Kt cu khu vc mi
tu.......................................................
..................25 3.4.1. Dn
boong.................................................................................25
3.4.2. Dn mn vng khoang
mi................................................................28
3.2.3. Vch
ngang.........................................................................30
3.5.Kt cu khoang my
.............................................................
...............33 3.5.1. Dn
y..................................................................................33
3.5.2. Dn
mn.............................................................................34
3.5.3. Dn
boong..................................................................36
3.6. Kt cu vng ui
tu..........................................................
.....................39 3.6.1.Dn boong vng ui
tu....................................................................39
3.6.2. Dn mn vng ui
tu......................................................................41
3.6.3. Dn
y.......................................................................42
3.6.4. Vch
ngang.........................................................................42
3.6.5. Kt cu sng ui
tu...................................................................
44 @@@.................................................@@@
KT CU TU THY
PGS.TS.TRN GIA THI
Li ni uTrong nhng nm gn y dung tch i tu vn ti ca nc ta tng ln
khng ngng nhm p ng nhu cu v vn ti hng ha. Cc mt hng chuyn ch rt a
dng v chng loi: Du th, kh ha lng, hng ri, hng kh, Container Hin
nay, Tu ch hng chim mt t trng rt ln, khong 50% s lng tu vn ti ca i
tu trn th gii v sc ch khng ln lm khong 4000 dwt n 10000 dwt, ln nht
l tu hng sc ch 20000 dwt. Nhm tu ny thng c b tr nhiu khoang hng vi
h thng np y c th ng m c v c cc h thng cn trc iu khin bng in hay thy
lc c th chuyn ch nhiu loi hng khc nhau Kt cu thn tu thy l mt mn hc
quan trng c v nh l xng sng trong trng trnh o to k s ngnh ng tu. Kt
cu thn tu nghin cu cc h thng kt cu v c im cc chi tit kt cu thn tu.
V mc ch cui cng l gip cho sinh vin thc hin c yu cu c c bn v kt cu v
tnh ton thit k kt cu theo quy phm. Yu cu quan trng ca vic thit k kt
cu l nghin cu cc phng php la chn hnh dng kt cu, xc nh kch thc, tnh
ton ti u kch thc, b tr hp l cc kt cu v lin kt ca thn tu m bo tu hot
ng an ton trong mi trng khc nghit . C nhiu phng php thit k kt cu
thn tu v mt phng php thit k kt cu m bo bn, an ton, t hiu qu v rt
ngn thi gian l thit k theo quy phm phn cp v ng tu. Qua nhng kin thc
hc cng vi s hng dn tn tnh ca thy gio b mn cng s cng tc ca cc bn
trong nhm, nhm em hon thnh bi tp ny. Mc d rt c gng nhng do kin thc
cn hn ch v y l ln u tin thc hin vic tnh ton thit k kt cu nn kh trnh
khi sai st. Rt mong nhn c s gp ca thy gio v cc bn. Nhm em xin chn
thnh cm n ! Nha Trang , ngy 5 thng10 nm 2011 SVTH : NHM 2
LP:51TTDT-1
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TNH KT CU THN TU THEO QUY PHMBi tp nhm mc ch hng dn sinh vin cch
thc s dng Quy phm ng tu tnh chn cc kch thc, la chn quy cch, phng n
b tr v kim tra bn cc kt cu. thc hin bi tp ny, sinh vin cn c k phn l
thuyt v c im kt cu tu, phn tch Quy phm tng ng la chn cng thc tnh
kch thc kt cu ph hp trn c s m bo c cc yu cu t ra khi thit k v b tr
kt cu v bn, tnh hp l, tnh kinh t v..v Trong phn ny c hai bi tp thc
hnh thng gp trong thc t - Tnh kt cu ca tu ng mi - Kim tra kt cu tu
thit k - Tnh kt cu ca tu hon ci Bi tp ny s hng dn cch tnh kt cu tu
ng mi theo yu cu ca Quy phm TCVN 6259-2A : 2003 1.GII THIU CHUNG
1.1.Cng dng, vng hot ng, quy phm p dng -Vng hot ng l vng khng hn
ch. - Kt cu tu c tnh theo Quy phm phn cp v ng tu bin v thp ca Vit
nam TCVN 6259-2A : 2003 - Vt liu dng ng tu theo quy phm TCVN 6259
2A : 2003 quy nh trong phn 7A. Thp dng ng tu c gii hn chy Y = 240
Mpa (2400 KG/cm2) hoc thp CT3 1.2.Cc thng s c bn v t s kch thc ca
tu
- Chiu di ln nht - Chiu di thit k - Chiu rng thit k - Chiu cao
mn tu - Chiu chm - Trng ti
: Lmax = 110 m : LTK =99,75 m : BTK =18,80 m : D = 13,00 m : d =
9,20 m : DWT = 10500 tn L - T s chiu di - chiu cao : = 7,67 D B - T
s chiu rng - chiu cao : = 1,45 D - Vn tc tu : v = 14,5 hl/h 1.3.La
chn h thng kt cu
< 20 < 4
Tu c t chc theo h thng hn hp vi cc hnh thc kt cu ca cc khung dn
tu nh sau : - Dn y, dn boong c kt cu theo h thng dc. - Dn mn, vng
mi v vng ui kt cu theo h thng ngang. - Vch ngang c kt cu theo hnh
thc np ng sng nm.
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KT CU TU THY
PGS.TS.TRN GIA THI
2.KHONG CCH SN V S PHN KHOANG 2.1.Khong cch sn. Khong cch sn c
tnh theo yu cu ca Quy phm c th nh sau :
Khong cch gia cc sn ngang s c tnh theo iu 5.2.1 ca Quy phmS =
450 + 2L = 450 + 299,75 = 649,5 mm.
Chn S =700 mm l khong cch sn ngang cho vng mn khu vc gia tu t
0,3L tnh t ng vung gc mi n 0,2L tnh t ng vung gc ui. Chn sn S = 600
mm l khong cch cho vng mn khu vc khoang li v khu vc khoang ui .
Khong cch gia cc dm dc s c tnh theo iu 5.2.2 ca Quy phms = 550 +
2L = 550 + 299,75 = 749,5 mm
Chn s = 750 mm khong cch gia cc dm dc cho ton b dn boong v dn y.
2.2.S phn khoang. Trn c s khong cch sn xc nh, chia chiu di tu thnh
153 khong sn thc vi khong cch sn cc khu vc nh sau : - Khong sn vng
ui tu - Khong sn vng gia tu - Khong sn vng mi tu : : : 600 mm (t sn
s -8 n sn 8) 700 mm (t sn s 8 n sn 128) 600 mm (t sn s 128 n sn
145)
Theo quy nh v phn khoang ca Quy phm, phn chia tu bng 6 vch ngn
kn nc vi chiu di ca cc khoang nh sau : Khoang li (1) gm 8 khong sn
t sn s -8 n sn s 0 : l1 Khoang ui (2) gm 8 khong sn t sn s 0 n sn s
8 : l1 Khoang my (3) gm 17 khong sn t sn s 8 n sn s 25 : l2 Khoang
hng I (4) gm 56 khong sn t sn s 25 n sn s 81 : l5 Khoang hng II (5)
gm 47 khong sn t sn s 81 n sn s 128 : l6 Khoang hm mi (6) gm 11
khong sn t sn s 128 n sn s 139 : l13 Khoang kt nc dn mi (7) gm 6
khong sn t sn 139 n sn 145: l14 = = = = = = = 4,8 4,8 11,9 39,2
32,9 7,40 3,55 m m m m m m m
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Hnh 2.1 l s phn khoang ca tu thit k 3.TNH CHN CC KT CU 3.1.Xc nh
ti trng boong 3.1.1.Boong thi tit Ti trng boong tnh ton c tnh theo
cng thc ghi trong chng 8 ca Quy phm, trong ti trng tnh ton tc dng
ln boong thi tit c xc nh theo cng thc : h = a (bf - y) (KN/m2)
trong : L a, b, y f (2.1)
- chiu di tu, c tnh bng L = 99,75 m - cc i lng c xc nh theo bng
2.1 ty thuc vo v tr boong. - v L < 150 m nn c cho theo cng thc
sau y. f=
L L e 300 + 1,0 10 150
L
2
= 6,6
Hnh 2.2 : Tr s ca f.
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KT CU TU THY
PGS.TS.TRN GIA THI
Bng 2.1 : Xc nh cc i lng a, b, y a TT V tr Tn boong X boong Ct
chng Sng boong b y (m)
I II III IV
Pha trc ca 0,15L tnh t ng vung gc mi T 0,15L n 0,3L tnh t ng
vung gc mi T 0,3L ng vung gc mi n 0,2L ng vung gc ui T pha sau 0,2L
ng vung gc ui
14,7 11,8 6,9 9,8
14,7 11,8 6,9 9,8
4,9 3,9 2,25 3,25
7,35 5,9 3,45 4,9
1,528 1,247 1,00 1,192
7,13 3,88 3,88 4,08
Thay gi tr tng ng trong bng 2.1 vo cng thc tnh trn xc nh gi tr
ti trng tnh ton h (KN/m2) tc dng ln kt cu boong theo gi tr cc i lng
a, b, y nh bng 2.2 Bng 2.2 : Gi tr ti trng tnh ton h xc nh theo gi
tr cc i lng a, b, y h(KN/m2) TT I II III IV V tr Pha trc ca 0,15L t
ng vung gc mi T 0,15.L n 0,3L t ng vung gc mi T 0,3L ng vung gc mi
n 0,2L t ng vung gc ui T pha sau 0,2L t ng vung gc ui Gi tr nh nht
ca ti trng tnh ton h (2.2) (2.3) Tn boong 43,44 51,33 18,77 37,11 X
boong 43,44 51,33 18,77 37,11 Ct chng 14,48 16,97 6,12 12,31 Sng
boong 21,72 25,67 9,38 18,56
Gi tr nh nht ca ti trng tnh ton h c tnh theo cng thc : hmin = C
L +50 - i vi dng I, II v III bng di y hmin = C L - i vi dng IV bng
di y. vi gi tr h s C trong cc cng thc trn c tnh theo bng 2.3 Bng
2.3 : Gi tr h s C C Dng I v II III V tr Pha trc 0,3L tnh t mi tu T
0,3.L ng vung gc mi n 0,2L t ng vung gc ui Tn boong X boong 4,2
2,05
Ct, sng dc, sng ngang boong 1,37 1,18 Trang 6
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KT CU TU THY
PGS.TS.TRN GIA THI
IV T sau 0,2L t ng vung gc ui 2,95 1,47 Thay cc gi tr C trong
bng 2.3 vo cng thc (2.2) v (2.3) nhn c gi tr nh nht ca ti trng tnh
ton hmin nh trong bng 2.4 Bng 2.4 : Gi tr nh nht ca ti trng tnh ton
hmin tc dng ln boong thi tit hmin (KN/m2) Dng I v II III IV V tr
pha trc 0,3L tnh t mi tu T 0,3.L ng vung gc mi n 0,2L t ng vung gc
ui T sau 0,2L t ng vung gc ui Tn boong 51,4 25,09 29,46 X boong
51,4 25,09 29,46 Ct, sng dc, sng ngang boong 16,77 14,44 14,68
Kt hp cc gi tr trong bng 2.3 v bng 2.4 c th xc nh c gi tr ti
trng boong tnh ton h (KN/m2) i vi boong thi tit theo bng 2.5 Bng
2.5 : Gi tr ti trng boong tnh ton h (KN/m2) h (KN/m2) Dng I II III
IV V tr Pha trc 0,15L t ng vung gc mi T 0,15.L n 0,3.L t ng vung gc
mi T 0,3.L ng vung gc mi n 0,2.L t ng vung gc ui T pha sau 0,2.L t
ng vung gc ui Tn boong 43,44 51,33 18,77 37,11 X boong 43,44 51,33
18,77 37,11 Ct chng 14,48 16,97 6,12 12,31 Sng boong 21,72 25,67
9,38 18,56
3.1.2.Boong vung kiu thng tng v lu Ti trng tnh ton h (KN/m2) tc
dng ln boong vung kiu thng tng lu c tnh theo cng thc tr sau : h =
12,8 m (KN/m2) 3.2.Chiu dy tn bao 3.2.1.Tn bao
Tn bao vng gia tuChiu dy cc tm tn bao on gia tu khng c nh hn gi
tr tnh trong bng 2.6 Bng 2.6 : Kt qu tnh chiu dy cc tm tn bao vng
gia tu Khu vc tn Tn y :- y di - y trn iu 14.3.4.2 4.5.1 Chiu dy tn
t (mm) Cng thc tnh C 1 C 2 S d + 0,035 L' + h 1 + 2,5C 'S h
+2,5
Gi tr 11,48 10,84 Trang 7
Chn 12 12
NHM 2-LP:51TTDT-1
KT CU TU THYDi tn y : - chiu rng - chiu dy Tn mn : - bn ngoi -
bn trong Tn mp mn Chiu dy ti thiu Di tn hng 14.3.5 14.3.1 14.2.1
14.3.2 14.3.2
PGS.TS.TRN GIA THI
2L + 1000 C 1 C 2 S d 0,035 L' + h 1 + 2,5 C 1 C 2 S d 0,125 D +
0.05 L + h 1 + 2,5'
1199,5 13,22 11,82 10,82
11200 14 12 12
C 1 C 2 S d 0,125 D + 0.05 L' + h 1 + 2,5-1 C 1 C 2 S d 0,125 D
+ 0.05 L' + h 1 + 2,5+1L
11,82 9,987
12 10 14
{5,22(d+0,035L) (R++2.5
a +b 2
) l}3 2
2 5
12,14
Tn bao vng mi v ui tuChiu dy cc cc tm tn bao (tn boong, tn y v
tn mn tu) vng mi v ui tu khng c nh hn cc gi tr cho trong bng 2.7
Bng 2.7 : Bng tnh chiu dy cc tm tn bao tu. Khu vc tn Tn bao vng mi
v vng ui Tn bao vng 0,3L t mt mi tu Tn bao vng 0,3L t mt ui tu Vng
gia cng y mi S = 0,45 m = 2 ; C = 1,33 ; V = 14,5 hl/h P - p sut va
p do sng P = 2,48(L.C1.C2)/ = 193,23 (KPa) C1 = 0,23 (chn C1 bng
2A/4.6) C2 = 0,667 V / L - 0,267 = 0,488 - dc y tu L = 0,0025 =
0,242 b b = 2,062 m Tn k vi sng ui mi t trc iu 14.4.2 14.4.2 14.4.2
14.4.1 4.8.4 t = CSP + 2,5
Chiu dy tn t (mm) Cng thc tnh 1,34 .S. L + 2,5 1,34 .S. L + 2,5
1,34 .S. L + 2,5 Gi tr 11,87 11,87 11,87 Chn 12 12 12
10.82 0,09L + 4,5 13,47
12 14
3.2.2.Tn boong Theo iu 15.4.1, chiu dy tn boong ca tu cc khu vc
khc nhau khng c nh hn cc gi tr cho trong bng tnh 2.8
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Bng 2.8 : Bng tnh chiu dy tn boong Chiu dy ti thiu t (mm) Vng tn
Vng I: trc 0,15L t mt mi tu. Vng II: sau 0,15L n trc 0,3.L t mt mi
Vng III: t 0,3L t mt mi n 0,2.L t mt ui Vng IV: sau 0,2.L t mt ui
tu iu 15.3..1-2 15.3..1-2 15.3..1-2 15.3..1-2 Cng thc tnh theo quy
phm 1,25.C.S Gi tr 10,82 11,51 9,56 10,47 Chn 12 12 10 12
h 1 + 2,5
1,25.C.S h 2 + 2,5 1,25.C.S h 3 + 2,5 1,25.C.S h 4 + 2,5
3.2.3.Tn vch. Theo iu 27.4.2 chiu dy tn phi khng c nh hn tr s
cua cng thc sau. t = 0,3S k ( L +150 ) +3,5 = 5,87 (mm). Trong : k
=1: l h s vt liu, ph thuc vo vt liu ch to ly cho trng hp thp thng
). S : Khong cch ca cc np gia cng . Chn S = 0,5 (m). Chn t = 6
(mm). 3.3.Kt cu khoang hng. 3.3.1.Vch ngang
Theo iu 27.4.1 ca quy phm, chiu dy tn vch khng c nh hn gi tr tnh
theo cng thc: = 9 (mm)
t = C 1 C 2 S. h + 3,5 Trong :
hng.
S - khong cch gia cc np vch, ly S = 0,7 m. h = max (h 1 , h 2 ,
h 3 ) =12,6608 (m). h 1 - Khong cch thng ng t mp di tn vch ang xt n
ming khoang h 1 = 12,6608 (m). h 2 - c xc nh theo cng thc h 2
=0,85(h 1 + h) = 12,09 (m). h - ct nc b sung xc nh theo cng thc: 16
(lt 10 ) + 0,25 (bt 10 ) =1,5 (m). h = L l t - Chiu di khoang hng.
l t = 39,2 (m). b t - Chiu rng khoang hng b t = 12 (m). h 3 - c xc
nh theo cng thc sau: h 3 = 0,3 L = 3 (m).
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PGS.TS.TRN GIA THI
C 1 = 1,0 C 2 = 3,6 k = 3,6 ( k=1 :ph thuc vo vt liu ch to ly
cho trng hp thp thng ) . Kt qu tnh chiu dy tn vch c trnh by trong
bng 2.9 Bng 2.9 : Bng tnh chiu dy tn vch Chiu dy ti thiu t (mm) Vng
tn Chiu dy di tn trn Chiu dy di tn cui iu 11.2.1 11.2.2 Cng thc tnh
theo quy phm 3,2.S h + 2,5 3,2.S h + 2,5 +1 Gi tr 10,45 11,45 Chn
12 12
Vch ngang c kt cu theo h thng ngang, gm c cc np ng, sng ng vsng
nm vi quy cch ca cc chi tit kt cu c la chn nh sau : Np ng L
125x75x10 450 x12 Sng ng T 1000 x12 480 x12 Sng nm T 1000 x12 Khong
cch gia cc chi tit kt cu ca vch ngn c la chn nh sau : - Khong cch
gia cc np ng, gia np ng vi sng ng s = 0,7 - Khong cch gia cc sng ng
ca vch l s = 2,1 - Chiu cao thng ng ca sng nm vch tnh tm tu h = 2,8
(m) (m) (m)
1
2
1.Np ng 2.Sng ng 3.Sng nm
700 700 700 700 700 700 700 700 700 700 700 700 700 700 700 700
2100 2100 2100 2100 2100
Hnh 2.3 : S b tr cc kt cu ca vch ngn ngang ca khoang hng Phn di
y tnh ton kim tra li quy cch kt cu la chn theo yu cu Quy phm. Np ng
vch Theo iu 27.5.2 ca Quy phm, gi tr mun chng un ca tit din np vch
khng c nh hn gi tr tnh theo cng thc sau y :
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PGS.TS.TRN GIA THI
W0 = 125.C 1 .C 2 .C3 . .S.h.l2 = 172,93 (m4). trong : S - khong
cch gia cc np ng, S = 0,7 (m) l - chiu di nhp np o gia cc ln cn np
k c chiu di ca lin kt, l = 2,8 m. h - khong cch thng ng t trung im
l, l np ng n nh ca boong vch o ng tm tu, h = 8,013 (m) . C 1 - h s
ph thuc vo L, chn C 1 = 1. k C2 = = 0,056, k = 1. 1 8 C 3 - ph thuc
vo cng ca 2 nt np c tra theo bng 2A/27.2, C 3 = 0,7. Mp km S = 10
mm nn chn chiu rng mp km b = min (0,2.l ; S) = 700 mm. Chn b = 700
mm Chn quy cch np ng vch l L125x75x10 Bng tnh chn thp: STT 1 2 Quy
cch 700x10 125x75x10 Fi (cm2) 70 19 A = 89 Zi (cm) 0,5 10,63 Fi.Zi
(cm3) 35 201,97 B = 236,97 Fi.Zi2 (cm4) io (cm4) 6,667 360
17,5 2146,94
C = 2531.11
T kt qu trong bng tnh trn c th xc nh c cc i lng nh sau : e Zmax
J W DW = = = = B/A = 2,66 (cm) 10,63 (cm) 2 C - e .A = 1901,38(cm4)
J/Zmax = 178,87 cm4
3.Sng nm75 10 125
(W Wo ).100% = 3,43% < 5% = Wo
10
Nh vy, quy cch np ng ca vch la chn trn tha mn c yu cu ca Quy
phm
800
Sng ng vchTheo iu 27.6.5 ca Quy phm, gi tr mun chng un ca tit
din sng vch khng c nh hn tr s tnh theo cng thc sau y : W trong : =
7,13.C 1 .k.Shl 02
= 5589,85 (cm3)
C 1 - h s ph thuc vo L, chn C 1 = 1. k h s vt liu ph thuc vo loi
thp, chn k = 1. S - chiu rng vng m sng phi , bng khong cch gia hai
sng ng, S = 2,8(m) l0 - chiu ca sng c xc nh theo cng thc sau: l 0 =
k 1 .l = 10,054 m. l chiu di ca ton b sng, l = 12,412 m. Trang
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KT CU TU THY
PGS.TS.TRN GIA THI
k 1 - h s hiu chnh do m c xc nh theo cng thc sau k1= 1
ngang.
0.65 (b1 + b2 ) = 0,81 l
b1 v b2 l chiu di cnh m ti cc mt tng ng ca sng b1 = 2,5.h 1 = 2
m. b 2 = 2.h 1 = 1,6 m. h 1 : chiu cao tit din sng ngang boong. h 1
= 700 mm. h - khong cch thng ng t trung im l, l sng ng n nh boong
vch o ng tm tu(m), ly h = 6,3304 (m). Mp km S = 12 mm b = min
(0,2.l ; S) = 700 mm, chn b = 700 mm. 450 x12 Trn c s chn sng ng
vch c quy cch T . 1000 x12 Bng tnh chn thpSTT 1 2 3 Quy cch 450x12
1000x12 700x12 Fi (cm2) 54 120 84 Zi (cm) 101,26 51,2 0,6 Fi.Zi
(cm3) 5468,04 6144 50,4 Fi.Zi2 (cm4) 553693,73 314572,8 30,24 io
(cm4) 18,77 230400 38,88
A = 258 B =11662,4 C = 1098754,42 T cc kt qu trong bng tnh trn c
th xc nh c cc i lng sau : e Zmax J W DW = = = = B/A = 45,2 (cm)
101,26 (cm) C - e2.A = 571650,1 (cm4) J/Zmax = 5645,36 (cm4) 2.Sng
ng 3.Sng nm
(W Wo ).100% = 0,994% < 5% = Wo
Nh vy, quy cch sng ng vch la chn tho mn yu cu ca Quy phm
Sng nm vch .Theo iu 27.6.5 ca Quy phm, gi tr mun chng un ca tit
din sng vch khng c nh hn tr s tnh theo cng thc sau y : W trong : =
7,13.C 1 .k.Shl 02
=
8881,51 (cm3)
C 1 - h s ph thuc vo L, chn C 1 = 1. k h s vt liu ph thuc vo loi
thp, chn k = 1. S - chiu rng vng m sng phi , bng khong cch gia hai
sng ng, S = 2,8(m) l0 - chiu ca sng c xc nh theo cng thc sau: l 0 =
k 1 .l = 5,184 m. Trang 12
NHM 2-LP:51TTDT-1
KT CU TU THY
PGS.TS.TRN GIA THI
l chiu di ca ton b sng, l = 6,4 m. k 1 - h s hiu chnh do m c xc
nh theo cng thc sau k1= 1 ngang.
0.65 (b1 + b2 ) = 0,81 l
b1 v b2 l chiu di cnh m ti cc mt tng ng ca sng b1 = 2,5.h 1 = 2
m. b 2 = 2.h 1 = 1,6 m. h 1 : chiu cao tit din sng ngang boong. h 1
= 800 mm. h - khong cch thng ng t trung im l, l sng ng n nh boong
vch o ng tm tu(m), ly h = 6,3304 (m). 480 x12 Sng nm vch c quy cch
T (gia cng hn) 1000 x12 Mp km S = 12 mm b = min (0,2.l ; S) = 700
mm . Chn b = 700 mmBng tnh chn thp STT Quy cch 1 2 3 4 700x14
110x12 480x12 1000x1 2 Fi (cm ) 112 13.2 57.6 120 A=302.82
Zi (cm) 0,7 6,9 102,2 51,4
Fi.Zi (cm ) 78.4 91.08 5886.72 6168 B=1224,23
Fi.Zi2 (cm ) 548.8 628.452 601622.7 8 317035.24
io (cm4) 38,88 177.47 34,13 14745,6
C=934831.32
T kt qu trong bng trn c th tnh cc i lng e Zmax J W DW = B/A =
102.2 = C - e2.A = J/Zmax = = 4.04 = 929889,14 = 9098,72 (cm) (cm)
(cm4) (cm4) 2.Sng ng
(W Wo ).100% = 2,44% < 5% Wo
Nh vy, quy cch sng nm la chn trn tho mn yu cu ca Quy phm
3.3.2.Dn boong Dn boong c kt cu theo h thng dc vi khong cch gia cc
x dc boong l S = 700 mm vi s kt cu nh m t trn hnh 5.3
NHM 2-LP:51TTDT-1
Trang 13
KT CU TU THY
PGS.TS.TRN GIA THI
2
5
3
4
1.Vch ngang 2.X dc boong 3.Sng ngang boong 4.Sng dc boong 5. X
ngang boong2100
1000
1000 3000
1000
1000
1000
Hnh 2.5 : Kt cu khung dn boong tu Sng ngang boong . Theo iu
27.6.5 ca Quy phm, gi tr mun chng un ca tit din sng vch khng c nh
hn tr s tnh theo cng thc sau y : W trong : = 7,13.C 1 .k.Shl 02
= 3182,54 (cm3)
C 1 - h s ph thuc vo L, chn C 1 = 1. k h s vt liu ph thuc vo loi
thp, chn k = 1. S - chiu rng vng m sng phi , bng khong cch gia hai
sng ngang, S = 2 (m) l0 - chiu ca sng c xc nh theo cng thc sau: l 0
= k 1 .l = 10.072 m. l chiu di ca ton b sng, l = 12,412m. k 1 - h s
hiu chnh do m c xc nh theo cng thc sau k1= 1 -
0,65 (b1 + b2 ) = 0,81 l
b1 v b2 l chiu di cnh m ti cc mt tng ng ca sngngang.
b1 = 2,5.h = 2000 mm b2 = 2.h = 1600 mm h: l chiu cao tit din
sng ngang boong. h = 520 mm h - khong cch thng ng t trung im ca S n
mp trn ming khoang hng: h = d + 0,038.l = 10,39 (m). chn h = 2,2
m.Mp km S = 12 mm ; b = min (0,2l ; S) = 500 mm Bng tnh chn thp STT
1 2 3 4 Quy cch 200x12 750x10 500x12 Fi (cm2) 24 75 60 A = 159 Zi
(cm) 76,2 38,1 0 Fi.Zi (cm3) Fi.Zi2 (cm4) 139354,56 108870,75 0 io
(cm4) 2,88 35156,25 7,2
700
700
700
1828,8 2857,5 0 B = 4686,3
C = 283391,64 Trang 14
NHM 2-LP:51TTDT-1
KT CU TU THY
PGS.TS.TRN GIA THI
T kt qu trong bng c th tnh cc i lng e Zmax J W Dw = = = = = B/A
= 2947 cm 47,33 cm C - e2.A = 145269,58cm4 J/Zmax = 3069,52 cm4 ( W
Wo ).100%
200
10 750
Wo Quy cch trn tho mn yu cu ca Quy phm
= 3,7% < 5%
500 12
X dc boong.
Theo iu 8.3.1 ca Quy phm, mun chng un ca tit din x dc boong khng
nh hn tr s tnh theo cng thc sau: 2 Z = 1,14.S.h.l = 133,66 cm3
trong : S - khong cch gia cc x dc boong (m), ly S = 0.7 m h - ti
trng boong, tnh theo bng 4, ly h =43,44 KN/m2 l - khong cch nm
ngang gia cc sng ngang hoc t sng ngang n vch ngn ngang (m), ly l =
2(m). X dc c qui cch L 125x125x10 Mp km S = 10 mm ; b = min (0,2l ;
S) = 700 cm Bng tnh chn thp Quy cch 700x10 125x125x10 Fi (cm2) 70
28,9 A = 98,9 Zi (cm) 0,7 12,01 Fi.Zi (cm3) 47 347,09 B = 396,09
Fi.Zi2 (cm4) 764,59 1851,94 io (cm4) 11,43 422
STT 1 2
C = 3049,96
T kt qu trong bng c th tnh cc i lng 2.Sng ng e Zmax J W Dw = = =
= = B/A = 4 cm 9,9 cm C - e2.A = 3049,96 cm4 J/Zmax = 308,23 cm4 (
W Wo ).100%
Wo Sng dc boong
= 2,69% < 5%
Theo iu 27.6.5 ca Quy phm, gi tr mun chng un ca tit din sng vch
khng c nh hn tr s tnh theo cng thc sau y : W trong : = 7,13.C 1
.k.Shl 02
= 3182,54 (cm3)
C 1 - h s ph thuc vo L, chn C 1 = 1. k h s vt liu ph thuc vo loi
thp, chn k = 1. Trang 15
NHM 2-LP:51TTDT-1
12
KT CU TU THY
PGS.TS.TRN GIA THI
S - chiu rng vng m sng phi , bng khong cch gia hai sng dc, S = 2
(m) l0 - chiu ca sng c xc nh theo cng thc sau: l 0 = k 1 .l =
10,072 m. l chiu di ca ton b sng, l = 12,412m. k 1 - h s hiu chnh
do m c xc nh theo cng thc sau k1= 1 ngang.
0,65 (b1 + b2 ) = 0,81 l
b1 v b2 l chiu di cnh m ti cc mt tng ng ca sng b1 = 2,5.h = 2000
mm b2 = 2.h = 1600 mm h: l chiu cao tit din sng ngang boong. h =
600 mm h - khong cch thng ng t trung im ca S n mp trn ming khoang
hng: h = d + 0,038.l = 10,39 (m). chn h = 2,2 m. Mp km S = 12 mm
chiu rng mp km b = min(0,2l ; S) = 700 mm, chn b = 700 mm.Bng tnh
chn thp STT 1 2 3 4 Quy cch 700x12 220x12 800x12 110x12 Fi (cm2)
128 26,4 78,8 -13,2 A = 220 Zi (cm) 0 82,4 82,4 7,45 Fi.Zi 0
2900,18 4218,88 -139,46 B = 8,85,82 (cm3) Fi.Zi2 (cm4) 0 97853,63
127369,97 -9246,67 io (cm4) 27,31 68266,67 10,92 -213,55
C = 174897,66
T kt qu trong bng c th tnh cc i lng e Zmax J W= DW = B/A = 32,5
(cm) = 50,68 (cm) = C - e2.A = 194667,52(cm4) J/Zmax = 3841,35
(cm4) =
( W Wo ).100% = 0,58 % < 5 % Wo220 x12 tho mn yu cu ca quy
phm 800 x12
Quy cch trn T 3.3.3.Dn mn
2 4 1 Khung dn mn tu c3 kt cu theo h thng ngang gm sn thng, sn
kho vi khong cch sn S = 500 mm, chiu dy tn mn tnh phn trn l t = 12
mm
NHM 2-LP:51TTDT-1
5
1.Tn boong 2.Sn thng 3.Sn khe 4.Sng dc mn 5.Tn y
Trang 16
KT CU TU THY
PGS.TS.TRN GIA THI
Hnh 2.6 : Kt cu khung dn mn
Sn thng thuc khoang hng trong vng 0,15L = 14,96 m t mi n vch
chng vaTheo iu 5.3.2.1 mmen chng un ca tit din sn ngang khoang : W
= C 0 .C.S.h.l2 = 382,75 (cm3) trong C 0 : H s tnh theo cng thc sau
y nhng phi khng nh hn 0,85. e C 0 = 1,25 = 2,83 l e - chiu cao cua
m hng o t mt di ca l (m). C - h s c gi tr C = 1,813 S - khong cch
sn S = 0,5 m l - chiu di nhp, l = 2,8 m h - Khong cch thng ng t mt
di ca l ti v tr cn o n im d + 0,038L pha trn ca tn gia y. h = d +
0,038L - 2 = 14,57 m. Mp km S = 12mm chiu rng mp km b = min(0,2l ;
S) = 500 mm, chn b = 500 mm. Chn sn ngang boong c quy cch
L125x125x14. Bng tnh chn thp STT 1 2 Quy cch 500x12 125x125x14 Fi
(cm2) 60 33,4 A = 93,4 Zi (cm) 0,6 12,21 Fi.Zi (cm3) 36 407,81 B =
443,81 Fi.Zi2 (cm4) 1034,22 1857,89 io 7,2 482
C = 3381,31
T cc s liu trong bng tnh cc i lng : e Zmax J W = B/A = 4,75 (cm)
= 8,95 14 (cm) = C - e2.A = 3381,31(cm4) = J/Zmax = 377,87 (cm4) (
W Wo ).100% DW= = 1,29% < 5 % Wo
125
125
500
14 12
Chn thp L125x125x14 lm sn thng khu vc mi l tho mn yu cu Quy
phm
NHM 2-LP:51TTDT-1
Trang 17
KT CU TU THY
PGS.TS.TRN GIA THI
Sn thuc khoang hng trong vng 0,15L = 14,96 m n vch ui.Theo iu
5.3.2.1, gi tr mmen chng un ca tit din sn ngang khoang hng trong
-vng 0,15L = 11,47 m n vch ui khng c nh hn gi tr tnh theo cng thc :
W trong : = C 0 . C * .S.h.l2 = 497,575 (cm3)
C * - h s c gi tr C = 1,3.C S, l, h tnh tng t nh trn
Mp km S = 12mm chiu rng mp km b = min(0,2l ; S) = 500 mm. Chn b
= 500 mm. Chn sn ngang boong c quy cch L 160x160x10 bng tnh chn thp
nh sau : Bng tnh chn thp STT 1 2 Quy cch 500x12 160x160x10 Fi (cm2)
60 34,4 A = 104,4 Zi (cm) 0,6 15,41 Fi.Zi (cm3) 36 530,1 B = 579,1
Fi.Zi2 (cm4) 1644,52 3346,41 io (cm4) 11,43 844
C = 5846,36
T cc s liu trong bng tnh cc i lng = B/A = 5,55 (cm) = 11,85 (cm)
= C - e2.A = 5846,36 (cm4) = J/Zmax = 493,24 (cm4) ( W Wo ).100%
DW= = 0,88 < 5 % Wo Nh vy, chn thp c quy cch L160x160x10 sn thng
khu vc ny l tho mn yu cu ca Quy phm e Zmax J W
2.Sng ng 3.Sng nm
Sn kheTheo iu 5.4.2/1 mun chng un ca tit din sn kho phi khng nh
hn tr s tnh theo cng thc sau y : W= trong : C 1 .S.h.l2 = 24978,42
(cm3)
C 1 - h s c gi tr C 1 = 6,33 S - khong cch sn kho, S = 2 m l -
khong cch thng ng t mt trn ca ngang y n mt trn cng ca sn kho , l =
10,912 m h - ti trng tc dng ln sn khe chiu chm ton ti d = 9,92 m h
= max (d + 0,044.L - 0,54 ; 1,43.l) = 16,57m
NHM 2-LP:51TTDT-1
Trang 18
KT CU TU THYTrn c s , tin hnh chn quy cch thp nh sau :
PGS.TS.TRN GIA THI
- Ly mp km S = 12 mm Chn chiu rng mp km b = min(0,2l ; S) = 500
mm. 600 x12 Chn sn khe c quy cch T v bng tnh chn thp nh sau : 1500
x12 Bng tnh chn thp STT 1 2 3 Quy cch 600x12 1500x12 500x12 Fi
(cm2) 72 180 60 A = 320 Zi (cm) 152,1 76,1 0 Fi.Zi (cm3) 18252
22830 0 B = 41082 Fi.Zi2 (cm4) 277129,2 1737363 0 io (cm4) 40
562500 44,37
C = 5076076,57 2.Sng ng 3.Sng nm
T cc s liu trong bng trn, c th tnh chn cc i lng nh sau : e Zmax
J W DW = = = = B/A = 77,51 (cm) 75,59 (cm) C - e2.A = 1891678,97
(cm4) J/Zmax = 25026,58 (cm4) ( W Wo ).100% = = 0,19% < 5%
Wo
Nh vy, quy cch sn khe c chn nh trn tho mn yu cu ca Quy phm Sng
dc mn Theo iu 27.5.1-2, gi tr mun chng un ca tit din sng dc mn khng
c nh hn gi tr tnh theo cng thc sau : W = 100.C 1 . C 2 .S.h.l2
trong : = 1369,51 cm3
S - khong cch sng dc mn, S = 2,8 m l - khong gia cc sng ngang
(m). l = 2 m. h - ti trng tc dng ln sng dc mn chiu chm ton ti d =
9,92 m h = d + 0,038.L = 16,57 m C1 - h s ph thuc vo L, chn C1 = 1.
C2 - h s ph thuc vo cng th sau : C2 = k =0,074 24 k
Trong :
k h s vt liu ph thuc vo loi thp . chn k = 1. = 10,5 Trang 19
NHM 2-LP:51TTDT-1
KT CU TU THYTrn c s , tin hnh chn quy cch thp nh sau :
PGS.TS.TRN GIA THI
Ly mp km S = 12 mm Chn chiu rng mp km b = min(0,2l ; S) = 500
mm. 260 x12 Chn sng dc mn c quy cch T v bng tnh chn thp 500 x10 Bng
tnh chn thp
STT 1 2 3 4
Quy cch 500x12 260x12 500x10 24x10
Fi (cm2) 60 31.2 60 -2,4 A = 148,8
Zi (cm) 0.6 51,8 26,2 10,15
Fi.Zi (cm3) 36 1616,16 1572 -24,36 B = 3199,8
Fi.Zi2 (cm4) 21.6 83717.1 41186,4 -247,25
io (cm4) 17,07 8,87 16666,67 -606,69
C = 140763,77
T cc s liu trong bng trn tnh chn cc i lng : = B/A = 21,5 (cm) =
= 51,8 (cm) = C - e2.A = 71980,97 (cm4) = J/Zmax = 1389,59 (cm4) (
W Wo ).100% DW = = 1,1,47% < 5% Wo Nh vy, quy cch ca sng dc mn
chn la trn tho mn c yu cu khot l sn thng c quy cch 125x125x14 chui
qua. 3.3.4.Dn y . e Zmax J W 2.Sng ng 3.Sng nm
Khung dn y c kt cu theo h thng dc vi khong cch gia cc dm dc s =
700 mm c m t nh trn hnh 2.5, vi lu chiu dy ca mi c cu trong y i ln
hn 6 mm4 5 6
3700 700 700
1000
1000 3000
1000
1000
1000
Hnh 2.7 : Kt cu khung dn y i Tn y
- Chiu dy tn y ngoi NHM 2-LP:51TTDT-1Trang 20
2100
2 1
1. Vch ngang 2.Dm dc y 3.Sng chnh y 4. Sng ph y 5. ngang c 6. Dn
mn
KT CU TU THYChiu dy tn ti thiu : tmin =L = 9,987 mm
PGS.TS.TRN GIA THI
Chiu dy tn (h thng dc) : t = C1C2S d + 0,035 L + h1 + 2,5 =
11,22 mm ; chn t = 12 mm
- Di tn gia y (tn sng nm) : gi nguyn trn sut chiu di tu vi kch
thcChiu rng tn sng nm bsn = 2L + 1000= 1199,5 mm Chiu dy tn sng nm
tsn = t + 1,5 = 13,5 mm ; chn tsn = 14 mm ; chn bsn = 1200 mm
- Chiu dy tn y trn (iu 4.7.1)tmin = C ' S h +2,5 = 10,84 mm ;
chn t =12 mm
Sng hng tuTheo iu 4.5.3, sng hng phi c chiu rng v su vo pha
trong tu tnh t ng chn m hng, vi chiu dy sng hng tsh tng thm 1,5 mm
so vi chiu dy tn y trn tsh = C ' S h +2,5 + 1,5 Sng chnh y v sng ph
y. = 13,34 mm ; chn t = 14 mm
- Theo iu 27.6.3.1, chiu dy ca sng chnh v sng ph c tnh theot =
max(t 1 , t 2 , t 3 ) = 14 mm. tmin =
C .a + 2,5 = 11,87 mm. k
'' 1
- Theo iu 4.2.3, chiu cao sng chnh v sng ph do, khng c nh hngi
tr B/16 = 1,75 m nhng trong mi trng hp khng nh hn 700 mm. Chn do =
1800 mm Chn sng chnh c qui cch dng thp tm : 1800 x 12 Chn sng chnh
c qui cch dng thp tm : 1800 x 12 - Np gia cng sng ph Theo iu
4.2.6-2 trong Quy phm, chiu dy ca cc np gia cng cho sng ph y bng
chiu dy tm sng ph, cn chiu cao ca tit din phi khng nh hn 0,08.do =
144 mm. Vy chn quy cch ca np gia cng sng ph c qui cch
L200x200x12
ngang c ( thp tm)Theo iu 4.3.2, ngang c b tr cch nhau khng qu
3,5 m
NHM 2-LP:51TTDT-1
Trang 21
KT CU TU THY
PGS.TS.TRN GIA THI
- Chiu dy bn thnh ngang khe (iu 27.6.3.2). t = max (t 1 , t 2 ,
t 3 ).
t1 = C 2 K
SbhB 2 y + 2.5 = 12,64 mm. d 1 b' d02 2 ' 1
t 2 = 8.63t3 =
H .a (t 2.5) + 2.5 = 9,01 mm C k2
8,5S 2 k
+2,5 = 6,75 mm.
Chn t = 14 mm Trong : S khong cch gia cc ngang c (m). Chn S = 2
m. b khong cch tn mn v vch dc tm o vng tn y gia tu (m). Chn b =
14m, b khong cch t vch dc ca mn kp ( gia hai cnh trong ca kt hng,
nu c kt hng ) n vch dc tm o theo mt tn y trn ngang ang xt (m). Chn
b = 12m. h B - tr s c xc nh theo cng thc sau. h B = max(h 1 ,h 2 )
= 10,502 m. h 1 = 0,6d + 0,026L = 10,502 m. h 2 = h ( d 0,026L) =
7,042 m. h khong cch t tn y trn n ming khoang hng. Chn h = 12,421m.
y khong cch theo chiu ngang ca tu ti ngang ang xt t tm ca b n im
ang xt (m). Chn y = 6m.
d 0 - chiu cao tit din c ti im ang xt (m). d 0 = 1,8 m. d 1 -
chiu cao l khot ti im ang xt (m). d 1 = 0. C 2 - h s ly theo bng
2A/ 27.10 ty thuc voB . Chn C 2 = 0,035. lH
a chiu cao ngang ti im ang xt (m). Chn a = 1,8m. C '2 - h s nh
theo bng 2A/ 27.11. Chn C '2 = 64. H tr s xc nh theo cng thc sau: -
Nu ngang cl khot khng c gia cng. H = 1 + 0,5 = 1. Trong : - ng knh
l khot (m). Chn = 0. - tr s no ln hn a hoc S .(m). - Trong cc trng
hp khc trn, chn H = 1. S 2 - bng S 1 hoc a, ly tr s no nh hn. Chn S
2 = 0,5m.1
K h s ph thuc vo vt liu, chn K = 1. Chn qui cch ngang y c dng
thp tm: 1800x12 Lin kt gia mn v ngang y bng m sn. - Np ng gia cng
ngang kho
NHM 2-LP:51TTDT-1
Trang 22
KT CU TU THY
PGS.TS.TRN GIA THI
Theo iu 4.3.3, bn cc np ng ln hn bn thanh thp dt c chiu dy bng
chiu dy ngang tm, chiu cao tit din ln hn 0,08do = 144 mm (do - chiu
cao sng chnh) Chn np ng gia cng ngang c L200x200x12. Do y i c kt cu
theo h thng dc nn theo iu 4.7.1 ca Quy phm th ti mi mt sn gia ca cc
sng dc phi b tr cc dc khung vi kch thc ca dm dc y trn v dm dc y di
tnh theo iu 4.4.
Dm dc y. - Gi tr mun chng un ca dm dc y di ln hn gi tr tnh theo
cng thc : W = 100. C1C 2 .Shl2
=
555,65 cm3
trong :
C - h s ph thuc vo L, C = 1 v L < 230 m. C 2 - h s xc nh theo
cng thc sau. k C2 = = 0,12 24 15 ,5 f B k
f B - t s gia m un chng un ca tit din ngang thn tu lm bng thp
thng v m un chng un thc thn tu ly ly i vi y tu, f B = 1. k h s vt
liu, ph thuc vo loi thp. k =1 i vi thp thng. l - khong cch gia
ngang y c, l = 2 m S - khong cch cc dm dc, S = 0,7 m h Khong cch t
dm dc ang xt n im cao hn mt trn ca tn gia y mt khoang tnh theo cng
thc: h = d + 0,026.L = 10,47 L chiu di tu, L = 99.75 m. Ly mp km S
= 12 mm Chn chiu rng mp km b = min(0,2l ; S) = 500 mm. Bng tnh chn
thp STT 1 2 3 Quy cch 500x12 L 160x160x12 Fi (cm2) 60 37,4 A = 97,4
Zi (cm) 0,6 15,51 Fi.Zi (cm3) 36 580,07 B = 616,07 Fi.Zi2 (cm4)
21,6 4377,89 io (cm4) 17,07 913
C = 5329,56
T cc s liu trong bng tnh cc i lng e Zmax J W DW = = = = B/A =
6,3 (cm) 12,11 (cm) C - e2.A = 6444,73 (cm4) J/Zmax = 532,01 (cm4)
( W Wo ).100% = = 4,44% < 5% Wo 3.Sng nm
NHM 2-LP:51TTDT-1
Trang 23
KT CU TU THYNh vy, quy cch ca dm dc y di L160x160x12 l tho mn yu
cu Quy phm
PGS.TS.TRN GIA THI
- Gi tr mun chng un dm dc y trn ln hn gi tr tnh theo cng thc sau
: W trong : = 100. C1C 2 .Shl2
=
555,65 cm3
C - h s ph thuc vo L, C = 1 v L < 230 m. C 2 - h s xc nh theo
cng thc sau. k C2 = = 0,12 24 15 ,5 f B k
f B - t s gia m un chng un ca tit din ngang thn tu lm bng thp
thng v m un chng un thc thn tu ly ly i vi y tu, f B = 1. k h s vt
liu, ph thuc vo loi thp. k =1 i vi thp thng. l - khong cch gia
ngang y c, l = 2 m S - khong cch cc dm dc, S = 0,7 m h Khong cch t
dm dc ang xt n im cao hn mt trn ca tn gia y mt khoang tnh theo cng
thc: h = d + 0,026.L = 10,47 L chiu di tu, L = 99,75 m. Ly mp km S
= 12 mm Chn chiu rng mp km b = min(0,2l ; S) = 500 mm. Bng tnh chn
thp STT 1 2 3 Quy cch 500x12 L 160x160x12 Fi (cm2) 60 37,4 A = 97,4
Zi (cm) 0,6 15,51 Fi.Zi (cm3) 36 580,07 B = 616,07 Fi.Zi2 (cm4)
21,6 4377,89 io (cm4) 17,07 913
C = 5329,56
T cc s liu trong bng tnh cc i lng e Zmax J W B/A = 6,3 (cm)
12,11 (cm) 12 2 C - e .A = 6444,73 (cm4) J/Zmax = 532,01 (cm4) 500
( W Wo ).100% DW = = 4,44% < 5% Wo Nh vy, quy cch ca dm dc y di
L160x160x12 l tho mn yu cu Quy phm160 12
= = = =
160
- Theo iu 4.4.4.2, din tch tit din thanh chng ng khng nh hn tri
s tnh theo cng thc sau:
Theo iu 4.2.4, dm dc y trn v y di lin kt vi sng chnh v sng hng
bng m c chiu rng ln hn 0,05B = 1400 mm v chiu dy ln hn chiu dy tnh
nh sau : 0,6 L + 2,5 = 10,44 mm, chn t = 12 mm.
Kt cu m ni
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16
KT CU TU THYChn qui cch m ni : 1400x12.
PGS.TS.TRN GIA THI
- Thanh chng dm dc. Theo iu 4.4.4, din tch tit din thanh chng ng
thng khng c nh hn cng thc thnh sau : A = 1,8CSbh = 9,74 cm 2 .
Trong : S khong cch gia cc dm dc, S = 0,7 m. b chiu rng m vng thanh
chng phi , b = 0,5m h chiu cao tnh theo cng thc sau ( nhng trong
moi trng hp khng c nh hn d ): h=
d + 0,026 L' + hi = 12,82. 2
L chiu di tu, L = 99,75 m. h i = 11,1708 m. C tnh theo cng thc
sau y nhng khng c nh hn 1,43:
1 0,5l s = 1,055. C= 1 kl s - chiu di ca thanh chng, chn l s =
1,6 m. k bn knh nh nht ca tit din thanh chng tnh theo cng thc sau:
I k= = 15,42. A I mmen nh nht ca tit din thanh chng, I = 913 cm4 A
din tch tit din thanh chng, A = 3,84 cm 2 . Chn qui cch thanh chng,
L250x250x12. - M sn M sn lin kt gia m hng vi sn c quy cch dng ch T
1400 x12 . 1800 x1800 x12 Theo iu 1.1.1.4 ca Quy phm, lin kt gia m
vi boong bng m, chn m c mp t do rng 1400 mm tit din ch
T1400x1800x12. - M hng Theo iu 4.6.1, chiu dy lin kt sn khoang vi
sng hng c tng thm 1,5 mm 0,6 L + +2,5 + 1,5= 11,94 mm, chn t = 12
mm Cn cnh t do c gia cng tm c chiu rng, b = 0,05B = 1,4 m. Chn m c
qui cch 1400x12. 3.4.Kt cu khu vc mi tu 3.4.1.Dn boong Dn boong tu
c kt cu theo h thng ngang, trong cc x ngang boong
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KT CU TU THY
PGS.TS.TRN GIA THI
t ti mi khong sn mi a =500 mm, sng dc boong t ti mt phng dc tm
tu (hnh 5.6) 1.X ngang boong thng 2.Sng dc boong 3.X ngang boong
kho 4.Sng chnh boong Hnh 2.8 : Kt cu khu vc mi tu
Chiu dy tn boong (iu 15.3.1)t = 1,25CS h + 2,5 = 12,82; chn t =
14 mm
X ngang boong iu 8.4.3 quy nh gi tr mun chng un tit din x ngang
boong khng nh hn : Wo trong : = 0,43 Shl2 = 118,7 (cm3)
S - khong cch gia cc x ngang boong, S = 0,50 m h - ti trng boong
tnh theo bng 3.5.1, h = 63 KN/m2 l - khong cch nm ngang t nh trong
ca m x n sng dc boong hoc l gia cc sng dc boong (m), l = 2,8 m
Ly mp km S = 12 mm Chn chiu rng mp km b = min (0,2l ; S) = 700
mm. Trn c s chn quy cch x ngang boong l L110x110x8 Bng tnh chn thp:
STT L S e Zmax J W Quy cch 700x12 110x110x8 Fi (cm2) 84 16,8 A =
100,8 Zi (cm) 0,6 8,55 Fi.Zi (cm3) 50,4 143,64 B = 194,04 Fi.Zi2 io
(cm4) (cm4) 30,25 27,31 1228,12 198 C = 1483,68
B/A = 1,925 (cm) 8,55 (cm) C - e2.A = 1110,15 (cm4) J/Zmax =
129,84 (cm4) ( W Wo ).100% Dw = = 4,38% < 5 % Wo Quy cch trn tho
mn yu cu quy phm Sng dc boong
= = = =
2.Sng ng 3.Sng nm
Theo iu (10.2.1), gi tr mun chng un tit din ngang ca sng dc
boong khng c nh hn gi tr tnh theo cng thc :
NHM 2-LP:51TTDT-1
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KT CU TU THYW= trong : 1,29.l.(l.b.h + kw) = 1906,83 cm3
PGS.TS.TRN GIA THI
l - khong cch gia cc ng tm ct, l = 4010,93 m. b - khong cch gia
trung im hai nhp k nhau c bi sng, chn b = 2,8 m. h - ti trng tc dng
ln sng dc boong, tnh theo bng 3.5.1, h = 25,67 KN/m2 . kw = 0
- Chn thp T gi tr mddun chng un nu trn, tin hnh chn quy cch thp
cho sng dc boong nh sau : Mp km S = 12 mm chn chiu rng ca mp km b =
min (0,2.l ; S) = 700 mm. 250 x12 Chn sng dc boong c quy cch T ta c
bng tnh chn thp nh sau : 600 x12 Bng tnh chn thp: STT 1 2 3 4 Quy
cch 700x12 110x12 600x12 250x12 Fi (cm2) 84 -13,2 72 30 A = 171,84
Zi (cm) 0 7,7 31,8 62,6 Fi.Zi (cm3) 0 -109,03 2289,6 1878 B =
4058,57 Fi.Zi2 (cm4) 0 -839,55 72809,28 117562,8 io (cm4) 38,88
-219,07 28800 8,53
C = 218121,99
T cc s liu trong bng tnh trn c th tnh c cc i lng nh sau : B/A =
23,62 (cm) 62,6 (cm) C - e2.A = 122251,7 (cm4) J/Zmax = 1952,9
(cm4) ( W Wo ).100% Dw = = 2,42% < 5 % Wo 250 x12 Nh vy, quy cch
sng dc boong T 600 x12 nu trn l tho mn yu cu ca quy phm e Zmax J W
= = = = 2.Sng ng 3.Sng nm
Ct chng Theo iu 9.2.1, din tch mt ct ngang ca ct chng khng c nh
hn gi tr tnh theo cng thc sau y :
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KT CU TU THY
PGS.TS.TRN GIA THI
trong :
0,233 .w 1 A1 = = 19,77 (cm3) 2,27 ko l - chiu cao ct chng c gi
tr l = 2,261 (m) ko - bn knh qun tinh ti thiu ca tit din ct. Chn ko
= 25 cm.
w - ti trng boong m ct (KN) tnh theo cng thc quy nh iu 9.2.2 w =
kw 0 + S.b.h = 184,95 (KN).
S - khong cch trung im hai nhp k nhau ca sng c ct , S= 2 m b -
chiu rng vng sng c gi tr b = 4 m h - ti trng boong m ct phi , h =
18,77 KN/m2 w 0 - ti trng boong m chic ct ni boong trn phi . w 0 =
20,55 KN k h s tnh theo cng thc sau y, ty thuc vo khong cch nm
ngang a i (m) t ct n ct ni boong trn, chia cho khong cch l j (m) t
ct n ct hoc n vch.a k = 2 i l j 3 ai +1 = 1 l j 3 2
T s liu trn chn ct chng c tit din l trn rng c ng knh ct d p =
250 mm vi chiu dy nh nht ca tit din ct tnh theo iu 9.2.3.1 t =
0,022.dp + 4,6 = 10,1 mm. Chn t = 12 mm Chn s b ct chng quy cch
250x12 ng knh trong ct chng dt = 226 mm. Trn c s tnh nghim li ct
chng theo quy phm vi h s = 0,9 I A2 = = d 4 p 64 1 4
(
)
= =
6590,86 cm4 89,68 cm2
2 dp d2 t 4
(
)
Nh vy ct chng c quy cch 250x12 la chn trn tho mn yu cu Quy phm
3.4.2.Dn mn vng khoang mi Dn mn vng khoang mi cng c t chc theo h
thng ngang nh trn hnh 5.7
NHM 2-LP:51TTDT-1
1.Sng dc mn Trang 28
KT CU TU THY
PGS.TS.TRN GIA THI2.Sn kho4 1
14400
25600
3.Sn thng 4.Sng mi
3
Hnh 2.8 : Kt cu dn mn khu vc mi tu Quy cch cc c cu khu vc mi tu
c tnh chn nh sau :
Chiu dy tn mn (iu 14.3.2)t = 12 mm
Sn ngang mn .iu 5.6.1 quy nh mun chng un tit din sn ngang di
boong mn kh nh hn W = 8.S.h.l2 trong : = 256,12 (cm3)
S - khong cch sn, S = 0,5 m l - khong cch hai gi ta ca sn mn, l
= 2 m h - ti trng tc dng, h = d + 0.038L = 16,57 m
Mp km S = 8 mm chn chiu rng ca mp km b = min (0,2.l ; S) = 500
mm. Chn quy cch L125x125x10. Bng tnh chn thp: STT L S e Zmax J W
Quy cch 500x8 125x125x10 Fi (cm2) 40 24,3 A = 64,3 Zi (cm) 0,4
11,81 Fi.Zi (cm3) 16 286,98 B = 302,14 Fi.Zi2 io (cm4) (cm4) 743,74
2,133 1224,27 360 C = 2330,14 2.Sng ng 3.Sng nm
B/A = 4,71 (cm) 8,59 (cm) C - e 2A = 2330,14 (cm4) J/Zmax =
271,33 (cm4) ( W Wo ).100% Dw = = 0,279% < 5 % Wo Quy cch trn
tho mn quy phm Sng dc mn
= = = =
Gi tr mun chng un tit din sng dc mn ln hn gi tr tnh theo cng thc
sau : W = 8Shl2 = 3393,54 cm3 Trang 29
NHM 2-LP:51TTDT-1
KT CU TU THY
PGS.TS.TRN GIA THI
trong :
S - chiu rng din tch c bi sng dc mn (m), S = 6,4 m l - khong cch
cc gi ta ca sng (m), l = 2 m h - ti trng tc dng, h = d + 0.038L =
16,57 m
Mp km S = 12 mm chn chiu rng ca mp km b = min (0,2.l ; S) = 500
mm. Chn chiu rng mp km b = 500 mm 350 x12 Chn sng dc boong c quy
cch T ta c bng tnh chn thp nh sau : 800 x12 Bng tnh chn thp:
STT 1 2 3 4
Quy cch 500x12 135x12 800x12 350x12
Fi (cm2) 60 -16,2 96 42 A = 181,8
Zi (cm) 0 8,55 41,8 82,6
Fi.Zi (cm3) 0 -184,68 5350,4 4625,6 B = 9791,32
Fi.Zi2 (cm4) 0 -19756,023 1157,48 107467,63
io (cm4) 24,3 -328,05 11,95 11,95
C = 156843,94
T cc s liu trong bng tnh trn c th tnh c cc i lng nh sau : e Zmax
J W Dw = B/A = 38,79 (cm) = 44,61 (cm) 2 = C - e .A = 156843,9
(cm4) = J/Zmax = 3516,12 (cm4) ( W Wo ).100% = = 3,6 % < 5 % Wo
2.Sng ng
Quy cch trn tho mn quy phm Lin kt - M lin kt gia sn mn thng vi x
ngang boong c quy cch nh sau : Chiu di cnh m lm = 1/8.l = 0,125 m
lm = max(lx boong ; lsn mn) = 1 m 1 125 x12 Chn m ch T 2 1000 x1000
x12 4.4.3.Vch ngang Vch ngang kt cu h thng ngang gm np ng, sng ng,
sng nm, khong cch gia cc np ng a = 800 mm, sng vch c t ngay ti mt
phng dc tm tu (hnh 5.8). Quy cch cc c cu vch ngang c tnh chn nh sau
:
NHM 2-LP:51TTDT-1
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KT CU TU THY
PGS.TS.TRN GIA THI
Chiu dy tn vch (iu 27.4.1) : t = 12 mm Np ng vchiu 11.2.3 quy nh
gi tr mun chng un tit din np vch ln hn tr s : W = 2,8.CShl 2 = 726
(cm3)
S - khong cch gia cc np ng thng (m), S = 0,7 m l - chiu di nhp
np, o gia cc ln cn np k c chiu di lin kt, l = 6,4 (m) h - khong cch
thng ng tnh t trung im ca np ng l cho n nh boong vch, o ng tm tu h
= 6,3304 m. C - h s cho bng 2 - B/11.2 tu thuc kiu cc lin kt mt np
bng m C = 1 Mp km 12 mm chiu rng mp km b = min (0,2l ; S) = 500 mm,
chn b = 500 mm. Chn np vch c quy cch L160x160x12. Bng tnh chn thp:
STT L S e Zmax J W Quy cch 500x12 160x160x12 Fi (cm2) 80 49,1 A =
129,1 Zi (cm) 0,8 15,91 Fi.Zi (cm3) 64 781,18 B = 845,18 Fi.Zi2 io
(cm4) (cm4) 2641,98 17,07 4304,65 1175 C = 8138,7160 12 160
= B/A = 6,55 (cm) = 11,05 (cm) = C - e2.A = 8138,7 (cm4) =
J/Zmax = 736,3 (cm4) ( W Wo ).100% Dw = = 1,42% < 5 % Wo Quy cch
trn tho mn yu cu quy phm
500 16
Sng nm np vch- Theo iu 11.2.6, gi tr mun chng un ca tit din sng
vch khng c nh hn gi tr tnh theo cng thc sau y : W trong : =
4,75.Shl2 = 985,31 cm3
S - chiu rng vng m sng phi (m), S = 2,8 m. l - chiu di nhp o gia
cc gi ln cn ca sng (m), l = 2,8 m h - khong cch thng ng tnh t trung
im l ca sng ng n nh ca boong vch o ng tm tu h = 6,3304m.
- Chn thp
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12
KT CU TU THY
PGS.TS.TRN GIA THI
Mp km 12 mm chiu rng mp km b = min (0,2l ; S) = 500 mm, chn b =
500 mm. 160 x12 Chn sng nm vch c quy cch T 400 x12 Bng tnh chn thp
: STT 1 2 3 4 Quy cch 500x12 400x12 160x12 176x12 Fi (cm2) 80 64
25,6 -28,16 A = 141,44 Zi (cm) 0 21,6 42,4 10,4 Fi.Zi (cm3) 0
1382,4 1085,44 -292,86 B = 2174,98 Fi.Zi2 (cm4) 0 2478,15 18693,69
-697,64 io (cm4) 17,07 8533,34 5,46 -726,9
C = 1017,27
T cc s liu trong bng trn tnh cc i lng : B/A = 15,38 (cm) 27,82
(cm) C - e2.A = 28303,15 (cm4) J/Zmax = 1017,27 (cm4) ( W Wo ).100%
Dw = = 3,24 % < 5 % Wo 160 x12 Nh vy, quy cch ca sng nm vch T
400 x12 c la chn tho mn yu cu ca Quy phm e Zmax J W = = = =
Sng ng sng nm-Theo iu 11.2.6, gi tr mun chng un ca tit din sng
vch khng c nh hn gi tr tnh theo cng thc sau : W = 4,75.Shl2 trong :
= 1970,63 (cm3)
S - chiu rng vng m sng phi (m), S = 6,4 m l - chiu di nhp o gia
cc gi ln cn ca sng (m), l = 2,8 m h - khong cch thng ng t trung im
ca sng ng l n nh boong vch o ng tm tu (m), h = 6,3304 m
- Chn thp Mp km 12 mm chiu rng mp km b = min (0,2l ; S) = 500
mm, chn b = 500 mm. 220 x12 Chn sng ng (sng kho) vch c quy cch T
500 x12 Bng tnh chn thp STT 1 Quy cch 220x12 Fi (cm2) 26,4 Zi (cm)
51,3 Fi.Zi (cm3) 1354,32 Fi.Zi2 (cm4) 69476,62 io (cm4) 3,17 Trang
32
NHM 2-LP:51TTDT-1
KT CU TU THY
PGS.TS.TRN GIA THI
2 3
500x12 500x12
60 70 A = 156,4
25,3 0
1542 0 B = 2896,33
39629,4 0
12500 11,43
C = 121620,62
T cc s liu trong bng trn tnh cc i lng : B/A = 18,52 (cm) 33,38
(cm) C - e2.A = 67984,62 (cm4) J/Zmax = 2036,61 (cm4) ( W Wo ).100%
Dw = = 3,35 % < 5 % Wo 220 x12 Quy cch sng ng sngnm vch T 500
x12 tho mn Quy phm Sng mi Theo iu 2.1.1, quy cch sng mi tu c tnh
chn nh sau : e Zmax J W = = = =
2.Sng ng
-
Chn kiu sng mi tm c chiu dy tn t = 1,5 L 50 + 3 =13,58mm, chn t
=14 mm - Chiu rng bn thnh sng mi bng 600 mm - Gia cng sng mi bng cc
m cch nhau 500mm v cc m ngang cch nhau 1m.
3.5.Kt cu khoang my 3.5.1.Dn y Dn y h thng ngang vi ngang t ti
mi khong sn cch nhau 500 mm, sng chnh v sng ph chuyn tip t khoang
hng sang t thm sng ph bng b my.1 2 32400
1.Bng my 2.Sng chnh 3.Sng ph 4. ngang y
4
Hnh 2.11 : Kt cu y khoang my Sng chnh v sng ph Sng chnh v sng ph
khoang my chuyn tip t khoang hng sang nn c quy cch ly ng nh khoang
hng l sng chnh y 1800x14 v sng ph y 1800x12.
ngang y c. NHM 2-LP:51TTDT-1Trang 33
KT CU TU THY
PGS.TS.TRN GIA THI
- ngang y c ly tng t vng khoang hng chuyn sang - ngang kho c quy
cch 1800x14 - ngang gim nh thay ngang khung c quy cch 1800x14 v c
khot cc lgim trng v l cho ngi chui vi chiu cao l trong phm vi 0,1B
k t mn tu, chiu cao ca l khot hl phi nh hn 1/5 ln chiu cao ca tit
din ngang : hl 1/5.do = 360 mm. Gia cc np ng c khot l chui c quy
cch 1080x540
B myDo tu c kt cu y i nn theo iu 19.2.2, cc sng ph b sung c t y
i, vi my chnh c cc kch thc l LxBxH = 3069x1000x2000 t trc tip ln tn
y trn. Chiu cao ca ng tm thnh b my c xc nh bng 900mm sao cho khi t
my th chiu cao ca ng tm trc my trng vi ng trc chn vt trong tuyn hnh
tu thit k. Da vo cc kch thc t y ccte ti ng tm trc ta c cc kch thc c
th nh sau : - Chiu cao thnh b my do = 1800 mm - Chiu dy tm thnh b
my S1 a3
Q + k = 15,05 mm, chn S1 = 18 mm (Q = 50 tn, k = 4, a = 3)
- Chiu dy bn cnh - Chiu dy m v tm m 3.5.2.Dn mn
a = 4,65 ; S2 a = 2,50 ; S3
= 13,13 mm, chn S2 = 14 mm = 11,21 mm, chn S3 = 12 mm
Dn mn c kt cu h thng ngang vi khong cch gia cc sn S = 500 mm, gm
cc sn thng xen k vi sn kho v sng dc mn t cch tn y trn 2,4 m. Cc sn
thng cch nhau 0,50m , cn cc sn kho t cch nhau 2 m (hnh v) 1.Sng dc
mn 2.Sn thng 3.Sn kho 4.Vch ngang
Hnh 2.12 : Kt cu dn mn khoang my
Sn thngTheo iu 5.3.2, gi tr mun chng un tit din ngang sn ln hn
gi tr sau: W C 0 CShl2 = 625,4 (cm4).
S - khong cch sn, S = 0,50 m
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Trang 34
KT CU TU THYl
PGS.TS.TRN GIA THI
- khong cch thng ng t mp trn ngang y n n mt trn ca x boong nh
sn, l = 1,662 m h - khong cch thng ng t mt di ca l ti v tr cn o n
im : d+0,038L=16,75 m pha trn ca tn y gia. Chn h = 14,75 m. C =
1,66 .e = 1,17 l Mp km 14 mm chiu rng mp km b = min (0,2.l ; S) =
500 mm, chn b = 500mm. Chn sn thng c quy cch L200x200x12.
C 0 = 1,25 - 2
Bng tnh chn thp: STT 1 2 Quy cch 500x14 200x200x12 e Zmax J W Dw
Fi (cm2) 70 46,56 A = 116,56 Zi (cm) 0,7 16,7 Fi.Zi (cm3) 49
777,552 B = 826,552 Fi.Zi2 (cm4) 34,3 12985,12 io (cm4) 57,6
3466
C = 16543
= B/A = 7,1 (cm) = 16,7 (cm) = C - e2.A = 10667,21 (cm4) =
J/Zmax = 638,75 (cm4) ( W Wo ).100% = = 2,13 % < 5 % Wo
2.Sng ng
Quy cch trn tho mn yu cu ca quy phm Sn kho (iu 5.4.2.2) - Chiu
dy bn thnh t ca ca sn khe l gi tr ln nht trong hai gi tr sau : t =
max (t1 ; t2) = 12 mm vi t1, t2 l hai h s c xc nh theo cng thc : t1
t2 =
C 2Shl 1000 d o
+ 2,5
= 10,74 mm
2 d o ( t1 2,5) + 2,5 = 11,72 mm k S - khong cch cc sn kho, S =
2 m l - khong cch thng ng t tn y trn n mt sn kho, l = 12,412 m h -
khong cch thng ng t trung im ca l n im , h = 1,43.l = 17,75 m L -
chiu di tu, L = 99,75 m do - chiu cao tit din sn kho, do = 0,1.l =
1,2412 m. Chn do = 1,25 m. C1, C2 - h s c gi tr C1 = 6,19 ; C2 =
51,4 i vi sn kho sau 0,15L t mi tu
= 8,6 3
NHM 2-LP:51TTDT-1
Trang 35
KT CU TU THYk - h s c gi tr k = 11,1 (Bng 2-A/6/2)
PGS.TS.TRN GIA THI
- Chn t = 12 mm - Gi tr mun chng un ca sn kho khng nh hn gi tr
tnh theo cng thc sau : W = C1.S.h.l 2 - Chn thp Mp km 14 mm chiu
rng mp km b = min (0,2l ; S) = 500 m, chn b = 500 mm. 850 x14 Chn
sn kho c quy cch T 1500 x12 Bng tnh chn thp: STT 1 2 3 4 e Zmax J W
= = = = Quy cch 500x14 1500x12 850x14 Fi (cm2) 70 18 11,9 A = 99,9
Zi (cm) 0,7 8,9 17,1 Fi.Zi (cm3) 49 160,2 203,49 B = 412,69 2.Sng
ng Fi.Zi2 (cm4) 34,3 1425,78 3479,68 io (cm4) 1837,8 472,6 312,43 =
330,5 (cm3).
C = 7562,59
B/A = 4,1 (cm) 17,1 (cm) C - e2.A = 5883,27(cm4) J/Zmax = 344,05
(cm4) ( W Wo ).100% Dw = = 4,1 % < 5 % Wo Quy cch trn tho mn yu
cu ca Quy phm 3.5.3.Dn boong
Dn boong ca khoang my c kt cu theo h thng ngang vi cc sng ngang
boong t cch nhau 2 m, cc x ngang boong t cch nhau 0,50 m (hnh 5.11)
1.X ngang boong kho 2.X ngang ming khoang 3.Vch kn nc 4.X ngang
boong thng 5.Sng dc ming khoang my 6.Sng dc boong
1
2 3 4 5
2400
KHOANG MA Y 6 0 x1 6 8 0 2 00
6
19500
Hnh 2.13 : Kt cu dn boong khoang my Tn boong Chiu dy tn boong ca
khoang my thuc vng 0,2.L k t ng vung gc ui v c tnh trong phn trc l
t = 12 mm
NHM 2-LP:51TTDT-1
Trang 36
KT CU TU THY
PGS.TS.TRN GIA THI
X ngang boong thng Theo iu (8.3.3), mun chng un ca tit din x
ngang boong ln hn gi tr W= trong : 0,43.Shl2 = 201 (cm3)
S - khong cch gia cc x ngang boong (m), S = 0,5 m h - ti trng
boong tnh theo bng (3.5.1), h = 39,02 KN/m2 l - khong cch nm ngang
t nh trong ca x n sng dc boong hoc gia cc sng dc boong (m), l = 3,2
m
Mp km 8 mm chiu rng mp km b = min (0,2l ; S) =500 mm,chn b = 500
mm. Chn x ngang boong thng c quy cch L90x90x8. Bng tnh chn thp: STT
1 2 3 e Zmax J W Dw = = = = Quy cch 500x8 L90x90x8 Fi (cm2) 40
96,56 A = 136,56 Zi (cm) 0,4 7,75 Fi.Zi (cm3) 16 748,34 B = 764,34
Fi.Zi2 (cm4) 6,4 5799,6 io (cm4) 2,133 94,3
C = 5902,433
B/A = 5,6 (cm) 7,75 (cm) C - e2.A = 1619,9 (cm4) J/Zmax = 209
(cm4) ( W Wo ).100% = = 3,98 %
