13.Huongdan Da Kcbtct 1

8/13/2019 13.Huongdan Da Kcbtct 1

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N KT CU BTNG 1

[1] TCXDVN356-2005, Tiu chun thit kb tng v btng ct thp, Nhxut bn Xy dng, 2006.

[2] TCVN 2737-1995, Ti trng v tcng Tiu chun thit k, Nh xut

bn Xy dng, 1995.[3] n mn hc kt cu b tng Sn sn ton khi loi bn dm (Theo

TCXDVN 356-2005), V B Tm (ch bin), Nh xut bn Xy dng,2007

B MN CNG TRNH GV: TS. Nguyn Minh LongKhoa K Thut Xy Dng E-mail: [email protected] Bch Khoa, TP. HCM

N KT CU B TNG 1 SN NH CNG NGHIP

Ti liu tham kho


2/38

1. Thit kbn sn

2. Thit kdm ph

3. Thit kdm chnh.

1. Tm tt ni dung n

2. Trnh tthit k

1. Xcnh s tnh v nhp tnh ton

2. Xcnh ti trng tc dng: tnh ti v h ot ti (tiu chun v tnh ton)

3. Thp ti trng v xcnh ni lc.

4. Tnh ton ct thp

5. Btr ct thp6. Biu vt liu

7. Thng k thp

8. Thhin bn v


Bn sn 1


3/38

3. BN SN MT PHNG3.1 Phn loi


Bn sn 2

a) Bn lm vic 2 phng: 2

1

2L

L

b) Bn lm vic 1 phng:

L1 chiud icnh ngn ca bn

L2 chiud icnh di ca bn

3.2 Xcnh sb kch thc cc bphn sn

a) Bn sn: 1b Dh Lm= m hsph thuc vo loi bn bn 1 phng: m =(30~35) bn 2 phng: m = (40~45)

D hsph thuc v o t i trng: D =(0.8~1.4)

b) Dm:- Dm ph:

1 1

12 16dp dph L

=

- Dm chnh:1 1

8 12

dc dch L

=

1 1

2 4b h

=

- Chiu rng dm:

Lu : Khi chn h v b, nhlm trn v nn chngi trl bi sca 50 mm !


4/38

Bn sn 3


3.3 Xcnh s tnh

EDCBA

L2L2L2L2 L2

F

4

3

L1

L1

L1

L1

L1

L1

L1

L1

2

1

L1

S O II

Dm chnh

Dm ph

Sn 1 phng Ct di c chiu rng b = 1m tnh

Sn tnh theo s khp do

1m

bdm

L1 L1L1

bdpLob1 Lo1

hb

1

bdp

hdp

bdp

2

Lo1

L1

Lo1


5/38

Bn sn 4


3.4 Xcnh ti trng

Trng lng bn thn ca cc lp cu to sn: f,i : hstin cy ca ti trng lp thi i : trng lng ring lp thI

hi : chiudy l p thi

3.4.1 Tnh ti(TT)

( ),s i i f ig h =

3.4.2 Hot ti(HT) Hot ti tnh ton: f,p : hstin cy ca hot ti pc : hot ti tiu chun

,s f p cp p=

3.4.3 Tng hp kt qu tnh ton ti trng

Bng 3.1 Ti trng tc dng ln sn (v d)


6/38

Bn sn 5


3.4.4 Thp ti trng

( ) 1s s sq g p m= + (ti trng trn 1 n v di !)

3.5 Xcnh ni lc

ps

L01 L01Lob1

gs

20

1

11 s bq L

20

1

11 s bq L

201

1

16 sq L

201

1

16 sq L

Hnh 3.1 S tnh v biu m-men

Gi tr ni lcc xcnh trn csxut hin khp do !

1

(kN/m)


7/38

Bn sn 6


3.6 Tnh ct thp

2mb b o

M

R bh

=

Tnh nhcu kin chu un c tit din b h = 1000 hb (mm)

Rb15 MPa : pl= 0.3 ; pl= 0.37 Rb > 25 MPa : pl= 0.255 ; pl= 0.3 15 < Rb25 MPa : ni suy plvpl

a) Chn a (a = 15 mm khi hb100 mm; a = 20 mm khi hb > 100 mm)

b) Tnh ho: ho = hb - ac) Tnh m,m :

d) Kim tra iu kin sdng ct nm plhocm pl

1 1 2 m =

e) Tnh din tch ct thpb b os

s

R bhA R

=

f) Kim tra hm lng ct thp

0.05% s b bmin pl o s

A R

bh R

= =

Tra bng suy ra slng

ct thp thc tV du: d10 a 150


8/38

Bn sn 7


3.6 Tnh ct thp (tt)

a) Chn ng knh: d6, 8, 10

3-3

2-2

1-1

As (mm2/m)@ (mm)d (mm)(%)(mm2/m)(kNm)

Chn ct thpAsmMTit din

Bng 3.2 Tnh ton ct thp cho sn

3.7 Btr ct thp

b) Khong cch ct thp: 100 @ 200 mm, chn gi tr chn tin thi cng !

c) Un ct thp: un theo gc nghing 30o hoc tl 1:2d) Ct thp cu to cho sn chng m-men m ti v tr cc gi bin v vng

giao tip vi dm chnh

As,ct= max (d6@200; 50%Asgia nhp)


9/38

Bn sn 8


3.7 Btr ct thp (tt)e) Ct thp theo phng 2 (phng cnh di) phn bnhsau:

,s pbA

20% As khi 2


10/38

Bn sn 9


3.7 Btr ct thp (tt)

Hnh 3.4 Btr thp bn sn

Trng hp hb100 mm (v d)

L1

L1/6 As,pb

L1

L1/4 L1/4bdp

As

L1/4 bdp

hb

1

1 2 3

1

2 3

2

11

3d8@200 d8@200

d8@200 2200 mm/thanh

L0b1 L01


11/38

Bn sn 10


3.7 Btr ct thp (tt)

Hnh 3.5 Btr thp bn sn

Trng hp hb > 100 mm:

L1

L1/8 As,pb

L1

L1/6 L1/6b

dp

As

L1/6b

dp

hb

1

1 2 3

1

2 3

2

11

3d8@200 d8@200

d8@200

Tn dng ct thp chu m-men dngnhp un ln gichu m-men m (v d)

L1/4 L1/4 L1/4


12/38

4. DM PH


Dm ph 11

EDCBA

L2L2L2L2 L2

F

4

3

L1

L1

L1

L1

L1

L1

L1

L1

2

1L1

S O II

Dm chnh

Dm ph

bdm

L2 L2L2

bdc bdcLob2 Lo2

hdp

AB C

hdc

4.1 Xcnh s tnh

Dm lin tc Tnh theo s khp do

Hnh 4.1 S dm ph


13/38

Dm ph 12


4.2 Xcnh ti trng

Trng lng bn thn ca dm: f,o : hstin cy ca ti trng dm BT, f,o = 1.1 bt: trng lng ring ca b tng, bt= 25 kN/m3

4.2.1 Tnh ti( )0 ,0f bt dp dp bg b h h =

4.2.2 Hot ti

1dp og g g= +

4.2.3 Tng ti trng tnh ton:

Tnh ti tsn truyn vo: 1 1sg g L=

Tng tnh ti:

Hot ti tsn truyn vo: 1dp sp p L=

dp dp dpq g p= +

4.3 Xcnh ni lcpdp

Lo2 Lo2Lob2

gdp

A B C

Hnh 4.2 Ti trng tc dngln dm ph


14/38

Dm ph 13


4.3 Xcnh ni lc (tt)

4.3.1 Biu bao m-men

4.3.2 Biu bao lc ct

202dpq L=

Lo2 Lo2Lob2

A B C

2dp oQ q L=

0.425Lob2

0.15L02

0.15Lo2 0.15L02

0.5L02

1 2 3 4 5 6 7 8 9 10 11

12

M

V0.4

0.6

0.5 0.5

0.5

Hnh 4.3 Biu bao m-men ca dm ph

Hnh 4.4 Biu bao lc ct ca dm ph


15/38

Dm ph 14


4.3 Xcnh ni lc (tt)

0.333-0.0180-0.0330-0.0625-0.0210-0.0210-0.0240-0.0400-0.01755.0

0.324-0.0160-0.0320-0.0625-0.0200-0.0200-0.0220-0.0390-0.01754.5

0.314-0.0150-0.0300-0.0625-0.0180-0.0180-0.0210-0.0380-0.01754.00.304-0.0130-0.0290-0.0625-0.0170-0.0170-0.0190-0.0370-0.01753.5

0.285-0.0100-0.0280-0.0625-0.0140-0.0140-0.0160-0.0350-0.01753.0

0.270-0.0060-0.0250-0.0625-0.0090-0.0090-0.0120-0.0330-0.01752.5

0.250-0.0030-0.0230-0.0625-0.0060-0.0060-0.0090-0.0300-0.01752.0

0.2280.0040-0.0190-0.06250.00000.0000-0.0030-0.0260-0.01751.50.2000.0130-0.0130-0.06250.00900.00900.0160-0.0200-0.01751.0

0.1670.0280-0.0030-0.06250.02400.02400.0220-0.0100-0.0175 0.5

12, 13111098765

H s min

ti cc ti t din

0.06250.0580.0180.0200.0750.0910.0900.0650.5L7, 8, 126, 9, 11430.425L21

k

H s max

ti cc ti t din

p/g

Bng 4.1 - Hs tnh tung biu bao m-men ca dm ph u nhp theo s khp do


16/38

Dm ph 15


4.4 Tnh ct thp

Tit din tnh ton ti gibf

hb

hdp

bdp SfSf

fS

(1/6)L2(1/2)L026hf

bf= bdp + 2Sf

hdp

bdp

Lo2 Lo2Lob2

A B C

Tit din tnh ton gia nhp

4.4.1 Tnh ct thp dc


17/38

Dm ph 16


Ti nhp tnh theo tit din chT, ti gi tnh theo tit din hnh chnht

Rb15 MPa : pl= 0.3 ; pl= 0.37 Rb > 25 MPa : pl= 0.255 ; pl= 0.3 15 < Rb25 MPa : ni suy plvpl

a) Chn a (a = 40~50 mm)

b) Tnh ho: ho = hdp - a

d) Tnh m,m :

e) Kim tra iu kin sdng ct nm plhocm pl

e) Tnh din tch ct thpb b o

ss

R bhA R

=

f) Kim tra hm lng ct thp

0.05% s b bmin pl o s

A R

bh R

= =

c) Nu tnh theo tit din chT phi kim tra v tr vng nn ca btng

4.4.1 Tnh ct thp dc (tt)

Tra bng suy ra slng

ct thp thc tV du: 4d16


18/38

Dm ph 17


4.4.2 Tnh ct thp ngang

a) Kim tra kh nng chng nn vca b tng di t c d ng ca US nn chnh

s

b

E

E= w

w

s

s b s =

b1 1 b bR =

= 0.01 vi btng nng, btng ht nh= 0.02 vi btng nh

w1 10.3 b b b oQ R bh

w1 w1 5 1.3s = +

Chn w1=1


19/38

Dm ph 18


4.4.2 Tnh ct thp ngang

Chn ng knh ct ai - d, chn snhnh - n

s = min (stt, smax, sct)

( ) 2222

1b f n b bt ott sw sw

R bhs R n d

Q

+ +=

( ) 24 1b f n b bt omax

R bhs

Q

+ +=

sctmin (h/2, 150 mm) nu h 450 mm

s = 150 mm

c) Tnh khong cch gia cc ct aivng gn gi (l/4)

d) Tnh khong cch gia cc ct aivng gia dm

sctmin (0.75h, 500 mm) nu h > 300 mm

b) Kim tra kh nng chng ct ca b tng

( )3 1b f n b bt oQ R bh + + b3 = 0.6 Btng nng

b3 = 0.5 Btng ht nh


20/38

Dm ph 19


4.5 Ct, un v neo ct thp

Xcnh vtr ct l thuyt

4.5.1 Ct ct thp

s,inc

sw

0.8Q-QW= 5 20

2qd d+

Xcnhon ko di W

- Q : l c ct ti tit din ct l thuyt

- Qs,inc : kh nng chu ct ca ct xin trong vng ct bt ct dc- qsw : kh nng chu ct ca ct ai ti tit din ct l thuyt

- Xcnh slng thanh thp dc cn ct

- Tnh kh nng chu m-men M ca tit din vi slng thanh thp dccn l i- Tm gi tr m-men M va tnh trn biu bao m-men ca dmxcnh

v tr ct l thuyt

sw swsw

R nAq =

s


21/38

Dm ph 20


4.5 Ct, un v neo ct thp

Bng 4.2 Gi tr on ko di W

4.5.1 Ct ct thp (tt)

(mm)(mm)(mm)(kN/m)(kN)(mm2)(kN)

WTT20dWLTqswQs,incAs,incQThanh thpTit din

4.5.2 Un ct thp Tn dng ct dc chu m-men dngnhp un ln gichu m-men

m hay lm ct xin chu lun lc ct.

Gc un ct thp:

- h 800 mm, = 45o

- h > 800 mm, = 60o

h-2ao

45o 60o

h-

2ao

h-

2ao


22/38

Dm ph 21


4.5 Ct, un v neo ct thp4.5.2 Un ct thp (tt)

im bt u un phi cch tit din trc mtonho/2 (nhm bomiukin chu m-men trn tit din nghing).

Khong cch t im cui ca lp ct xin thnhtnimu ca lp ctxin thhai phi < smax

Trong trng hp ct xin khng kh nng chu lc c t hsdng ct vai b> h0/2

h0/2smax

> h0/2

h0/2


23/38

Dm ph 22


4.5 Ct, un v neo ct thp4.5.3 Neo, ni ct thp

Chiu dion neo cn theo qui nh nhsau:

lan

3

0d

lan 15d

Chiu dion ni cn theo qui nh nhsau:

-on ni trong vng ko: 30d

-on ni trong vng nn: 20d

20d

20d


24/38

Dm ph 24


4.6 Biu vt liu4.6.1 Khi nim

Biu vt liu thhin kh nng chu lc (m-men M) thc tca tngtit din ca dm.

Biu vt liu cn bm st biu bao m-men nhm tn dng tiakh nng chu lc ca vt liu.

Biu vt liu c trc honh l trccuad m v truc tung l trc gi tr

ca m-men M. Biu vt liu thhin tnh chnh xc v mc hp l ca vic tnh

ton, sbtr ct thp trong dm.

4.6.2cim

Trong on dmc t it din, sthanh thp khng i, biu c dngng nm ngang

Tiim ct l thyt, biu c bc nhy Trong on un ct thp, biu c dngng xinng vi im bt

u v k t thc caon un.


25/38

Dm ph 25


4.6 Biu vt liu4.6.3 Trnh tthnh lp biu vt liu

Hon thnh vic tnh ton v btr ct thp trong dm

Vbiu bao m-men M trn mt ct dc ca dm.

Dkin trc phngnct, un ct thp.

Vmt ct dc ca dm ng tl.

Xcnh v tr ct l thuyt ca ct thp

- Tnh kh nng chu m-men ca tit din dm trc (M1) v saukhi ct thp (M2)

- Thhin ng tl (M1) v (M2) ln biu bao m-men bnghai ng nm song song vi trc dc ca dm vi qua ccgi trM1 v M2

- Giaoim cangi qua gi trM2 vi biu bao m-men nh du v tr ct thp l thuyt.

- Tnhon ko di W xcnh v tr ct thp thc t.


26/38

Dm ph 26


4.6 Biu vt liu

4.6.3 Trnh tthnh lp biu vt liu (tt)

Xcnh v trim un ca ct thp

- Tnh kh nng chu m-men ca tit din dm trc (M1) v sau khi unthp (M2)

- Thhin ng tl (M1) v (M2) ln biu bao m-men bng hai ngnm song song vi trc dc ca dm vi qua cc gi trM1 v M2

- Trnngi qua gi trM1, im btu un snm ti v tr cch gitrM1 mt khong ho/2. Tv tr ny v ng xin so vi trc dm theogc bng vi gc un ca ct thp, ng xin ny sctng ngang diqua gi trM2 ti mtim.im ny chnh lim kt thc un.

- on xin vacp thhin kh nng chu lc thc tca dm trong

on un ct thp.


27/38

Dm ph 27


4.6 Biu vt liu4.6.4 Tnh kh nng chu lc ca tit din

a. Xc nh li chiu cao lm vic ca dm

b

h

ho,tt

a1

As1a2

As2

att,o tt tt h h a=

1 s1 2 s2

s1 s2

A A

A Att

a aa

+=

+

b. Lp bng kt qu tnh ton

4

3

21

(%)(kNm)(mm)(mm)(mm2)

MMmho,ttattAsGhi ch ct thpTit din

Bng 4.3 Kh nng chu lc ca tit din


28/38

Dm ph 27


4.6 Biu vt liuV d (Lu y chl chl v d mang tnh minh ha, do trang sile kch thc nh

nn khng ththhin ht cc thng scng nhcc chtiu. C thhn cntham khoti liu s3 trangu tin ca bi ging ny)

35

45

1

1

2

2

3

3

4

4

5

5

Cho dm nhhnh v. Di t c d ng ca ti trng, m-men ti gia nhp ca dmMn =35 kNm v ti gi lMg= 45 kNm. Gisvi Mn = 35 kNm, cn thit phi btr

(2d16+ 1d20) v vi Mg= 30 kNm, cn (3d20+2d16).

W4

W3

30

(2d16) (2d16)

30

(2d16+1d20)38

38

(3d20+2d16) 4949

32(3d20)

10(2d20)


29/38

Dm ph 28


35

45

1

1

2

2

3

3

4

4

5

5

W4

W3

30

(2d16) (2d16)

30

(2d16+1d20)38

38

(3d20+2d16) 4949

32(3d20)

10(2d20)

2d12

2d16

2d12

2d16

2d20

2d16

2d20

2d16

1d20

1

2

5 5

21d201 1d201

2 2

3 31d20

1

2d20

2d16 2

3

11d20

4 2d16

1d201

5 2d12

2 2d16

3 2d20

4 2d16


30/38

Dm ph 29


4.7 Thng k vt liu4.7.1 Cch thng k ct thp

- Cc thanh thp c cngng knh, hnh dng v kch thc sk hiu cng mts

4

3

21

(kg)(m)(mm)(mm)(mm)

Trng lngTng chiudi

Slngthanh

Chiu di1 thanh

ngknh

Hnh dng vkch thc

Skhiu

Tn cukin

Bng 4.4 Thngkct thp

- Thp sn nn thng k trong tng bn, sau nhn vi slng bn sn ct thanh thp thng k

- Thp dm, m tng thanh trong dm ri nhn vi slng thanh

4.7.2 Cc bng thng k vt liu


31/38

Dm ph 30


4.7 Thng k vt liu

Trng lng (kg)

ng knh (mm)

Nhm thp

Bng 4.5 Tng hp ct thp

4.7.2 Cc bng thng k vt liu (tt)

Ton sn

Trng lng ct thp trn 1 m2 din tch mt sn (kg/m2):

Dm chnhDm ph

Bn sn

(kg/m3)(mm)(mm)

Hm lng ct thp trong 1 m3 b tngTrng lngct thp

Thtch btng

Tn cukin

Bng 4.6 Chtiu kinh tkthut



32/38

5. DM CHNH


Dm chnh 31

EDCBA

L2L2L2L2 L2

F

4

3

L1

L1

L1

L1

L1

L1

L1

L1

2

1

L1

S O II

Dm chnh

Dm ph

3L1

hdp

1 2 3

hdc

5.1 Xcnh s tnh

Dm lin tc Tnh theo s n hi !!!

4

L1 L1 L1 L1 L1 L1 L1L1 L1

3L1 3L1



33/38

5. DM CHNH


Dm chnh 32

5.2 Xcnh ti trng

Ti trng truyn ln sn,sn truynvod m phu,

dm ph truyn lnd mchnh di dng ti tptrung

3L1 3L1

hdp

1 2 3

hdc

4

L1 L1 L1 L1 L1 L1 L1L1 L1

3L1

P

G

P

G

P

G

P

G

P

G

P

G

P Hot tiG Tnh ti

L1 L1

hdphdc

0.5L1 0.5L1

hs



34/38

5. DM CHNH


Dm chnh 33

5.2 Xcnh ti trng

Ti trng truyn ln sn,sn truynvod m phu,

dm ph truyn lnd mchnh di dng ti tptrung

P

G

P

G

P

G

P

G

P

G

P

G

P Hot ti

G Tnh ti

L1 L1

0.5L1 0.5L1

hdphdc

hs

a) Tnh ti - G G = Go + G1Go Trng lng bn thn dm chnh: Go = f bt bdc So

So

So = (h hs)L1- (hdp- hs)bdpG1Tnh ti dm ph truyn lnd m chnh: G1 = gdp L2

b) Hot ti- P

G1Hot ti dm ph truyn lnd m chnh: P = pdp L2



35/38

5. DM CHNH


Dm chnh 34

5.3 Thp ti trng v xcnh biu bao m-men v lc ct

a) + b1) Biu m-men M1

G G G G G G

P P P P

P P P P

P P P P

a)

b1)

b2)

b3)

a) + b2) Biu m-men M2 a) + b3) Biu m-men M3

Vchng cc biu m-men M1, M2,

M3 ln cng mt h trc ta vi cngmt tl, biu bao chnh lngvin ngoi cng ca cc biu trn.

G

P

G L

P L

=

= (hs traph lc 9, ti liu s3 trangu

tin ca bi ging ny)



36/38

5. DM CHNH


Dm chnh 35

5.3 Thp ti trng v xcnh biu bao m-men v lc ct

a) + b1) Biu m-men Q1

G G G G G G

P P P P

P P P P

P P P P

a)

b1)

b2)

b3)

a) + b2) Biu m-men Q2 a) + b3) Biu m-men Q3

Vchng cc biu lc ct Q1, Q2,

Q3 ln cng mt h trc ta vi cngmt tl, biu bao chnh lngvin ngoi cng ca cc biu trn.

G

P

Q G

Q P

=

= (hs traph lc 9, ti liu s3 trangu

tin ca bi ging ny)



37/38

5. DM CHNH

sw sw

1

A R

dc dp

o

h hF

hmn


Dm chnh 36

5.4 Ct treo

hdphdc

hs

bdp 5050

s 50

bdp 5050

s 50 hdp hdc

hs

10d: vng chu nn20d: vng chu ko, ,

sw sw

1 2 sin

A R

dc dps inc s inc

o

h hF A R

hm

n



38/38

5. DM CHNH


Dm chnh 37

Cc mc khc (tnh ton ct thp, biu vt liu, btr ctthp) tng tnhtrong phn dm ph !!!

Documents

13.Huongdan Da Kcbtct 1