CAU T~O NEN MONG VA TUONG NHA
2/ M6ng chiu tai trong dQng: (Hinh 2-13)
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, I 1..2 : Ban vorn nguoc : Ap dung khi co yeu cau v~d¢ chiu udn Ian. D6i vel cong trinh khong len, ban vom co th~ cau tao bang gach da xay, betong vdi e = (0,301 + 0,30m) va
d¢ yang cua vom f = 1/71 - 1/101 .
1-3 : Ki~u co siren : Chieu day cua ban d1i9'C chon e = ir 1 - .Jr 1 vdi
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toan b¢ nha co tang ham, kho, b~ ve sinh, b6n chira nircc, hd bci, nha nhieu tdng co ke't csu chiu hrc nhay lun khong d~u. Mong be ducc cau tao bang cac y~t li~u chu ye'u Iii bstong va betong c6t thep theo cac hinh thirc sau :
1-1 : Ban p hang (mong tran n~n phu). Thong thirong chieu day cua ban diroc c11Qn
~.=1/61 vel khoang each gitta cac cQt 1 < 9m va tai trong 1000 t6n/c¢t.
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4/- M6ng dum nuoe :
Giai phap mong toi llU cho cong trinh dU<1inU<1cla th\1c hi~n cac lo~i mong' sau.
Tuy nhien khi co yeu cau cau ~o va thl1c hien m6ng trl1c tiep len dat nen chlu tai cao
(j duOi day nU<1Cthi tuy thea m6i truC1ng hQ'p rna co the chQn bi~n phap thi cong thea 3 phuong cach nhu sau :
4.1: D~pt~m, vong vay (H.2-15a) : bao quanh Vl tri xay mong vOi d~p t~m duqc cau t~o bling dat set, CQCvan g6, thep, betong cot thep. Khi chieu sau h cua nUO'c0,80m, dung d~p t~m b~ng dat set, vOi h>0,80m dung d~p dat co tang euemg CQCvan go, thep ho~e betong cot thep. Chieu rQng 1 eua than d~p tuy thuQc vao ehieu cao h clla m'l1c
nUO'c, vOi h < 2,50m ; 1 = h, h > 2,50m, I = h + 1/2 (h - 2,50).
4ã2 : Xay, due ehim (H.2-15b) : Ap d1.}.ngtrong tTUemghero nU<1CdUng yen va khong
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thep. TUy thea chieu dai va chieu r<}ngcua cong trinh, khoang each giiia cac khe duqc chia trong giOi han 30 < 1 < 40m. Khe co dan c~t nha den rmrc ga mo ng vi the mong
cua cQt kep, tuang vach cUng (j vi tri khe nhiet do duQ'c cau t~o thanh mQt khoi lien
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nhau. Thong thuemg khe co dan va khe lun (neu co) nen chQn trung nhau tren m~t bang cua cong trinh kien truc.
b ecru tao mongo. khe liin :Phan mong thanh hai phan rieng g9i la mong khe lun vdi chieu rong cua khe la 2cm -3cm. Khi tai trong nho, mong co th~ lam khong doi xirng (rnong lech tam). Khi tai trong krn, mong lam theo hinh thirc phan doan xen ke.
f>ai vrri mong d khe cau tao can phai xet tdi trong tai cua nha moi va kha nang mong cua cong trinh san co. Khi xay mong mci, c~n co bien phap tich eire d~ khong gay anh huang tac hai d~n cong trinh hoac phil hoai mong nha cu. Trong trircng hop ndy co t11~ap dung hinh thirc dam COl1gxon, mong mrri va cii tach rrri nhau .
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3-2 : (J khe eo dan (khe nhiet deằ : Khe co dan duoc cau tao d~ chan dung hien tuong mrt ne l~m hu hong cac be>phan ben tren cua cong trinh do anh huang cua su thay d6i nhiet dO, lam bien dang k~t cau cong trinh nhat la dai vdi ke't cau betong c6t
.,
3-J : (Jkhe Inn: Mong se diroc cau tao d vi trf rna cong trinh co kha nang san sinh
ra lun kh6ng d~u va g~y nen hien tirong nirt, gay ket cau cong trinh,
a Truo-ng hq-p ecru too khe liin 0- mong :
ai : Cong trinh qua dai hoac tai trong cua cong trinh phan b6 tuong doi khac nhau hoac co sai biet v~chieu cao 10m.
a2 : Giai phap mong trong cling mot cong trinh buoc phai chon khac nhau vi tinh
chat cua dat n~n thay d6i qua nhieu hoac dat nen chiu tai khong deu.
a3 : V] tr itiep giap gitra nha cii va nha mrri, trircng hop n~y ap dung giai phap mong
d khe cau tao.• ã
241
- - x
- - x
- - x
- - x
125mm 180
240 180 240 240
125 x
125 x
125 x
180 x
180 x
240 x
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x
- -
1/2 g~ch 3/4 g~ch
I g,:\ch 3/4 g~ch
1 g(;\ch I gC;lch 1/2 g~ch x
1/2 g~ch 1/2 g~ch 3/4 g~ch 3/4 g~ch
I g~ch
b- Quy each:
- Kfch thu<1ccac dUOng 6ng thong hoi va thoat kh6i thuOng bang Chieu day 1/2 g~ch + 2 m~ch vila = (105 + 20)
Kfch thuac 16 thoat kh6i thuOng lam co m~y co chinh :
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a- V! tri : Ong khoi va 6ng thong hoi nen b6 trf a nrong trong, khong nen b6 trf a
tuong ngoai VI v~ mua dong khong khi trong 6ng khoi va 6ng thong hoi bi lanh lam trc ngai cho hru thong khong khi, do do anh huong t61 thoat khoi va thong hoi, khi b6 trf nhieu dirong Dng khoi va thong hoi, t6t nh~t nen b6 tri t~p trung tai mot ch6. Vi nhu v~y kh6ng khi ben trong cac dUOng 6ng chju anh hUOng cua nhi¢t dQ t~o di~u ki¢n thu~n lqi cho viec thoat kh6i va thoat hoi .•
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qua sau (h < 1,50m). Vng dung phirong phap dO b.etl>ng dudi mnrc vdi loai b~tl>ng ke't cltng nhanh, bang each dung bao tai hoac dung 6ng di chuysn thang dirng' d~ dua betong
VaGvi tri hoac phun vira ximang.
4-3 : Gie'ng chim hoi ep (H.2-15c) : Khi tinh hinh dia chat thuy van phirc tap, dat tren mat la ye'u va d~y hoac ng~p mnrc, lai khong th~ ap dung giai phap mong tren CQC hoac gie'ng chim thi co th~ xlt Iy thanh gie'ng chim hoi ep g6m 2 bQ phan chmh : budng gi6ng, than gie'ng.
Budng gie'ng la ch6 chira khi nen d~ dAy nuoc ra ngoai va la .nci d~ cong nhan thao taco Than gie'ng la ke't cAu chu yeu cua mong sau khi gie'ng ha den dO sau thiet ke'.
N goai ra, con co buong hot ep la b¢ phan d~ ngutrl ra VaGbudng gieng ddng thoi d~
di chuydn vat lieu va se diroc thao gfJ khi thi cong xong mongo Tuy gie'ng chim hoi ep la mot ki~u mong sau co hieu qua nhirng viec thi cong no khong phai d~ dang cdng k~nh, thinrng d~ gay nguy hi~ln cho cong nhan hie thao tac trong budng gie'ng~ Gia thanh cao.
IV Cau tao tumlg co dumlg 6ng.
4-1 : Tltang co dUdng ong khoi, thong hoi: (H3-14) Trong kie'n true dan dung
d~ thoat hoi va kh6i tlt bep, tlt cac 10 sUdi hoac thong gi6 trao d6i khong khi, trong .
A .
,:truong hop can thiet phai lam cac 6ng kh6i va 6ng thong hoi Am VaGthan tmrng d~
i tang them 6n dinh, .
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- Dien tich tiet dien 6n.g kh6i : Loai thong dung 400mm2
Loai d~c biet 650mm2 (d nha an tap th~, cac cira hang)
- Chieu day ducng ong khong nen nho hon 1/2 gach ( 105mm), phia trong dircng
ong can dircc cau tao that phang d~ d~ thoat khoi. D~ thi cong thuan tien co th~ dung
dirong ong bang dat nung hoac betong due san d~ thay gach, ong sanh co cac loai : 100,
120, 150,200,250 va 300. (Hinh H3-14).
- Chieu cao 6ng kh6i : D~ tranh gi6 dap VaG6ng khoi gay kho khan cho vise thoat khoi, 6ng khoi Call phai cao hon mai nha, dQ cao phu thuoc VaG khoang each tir 6ng kh6i de'n dinh l10Cnha, chieu cao nho khoi mai khong duoc nho hen 30cln, cang xa dinh
mai dO cao co th~ giam (H3-14). BQ phan nho len cao nell dung vira mac cao d~ xay,
tuong ong kh6i nen lam thang, neu phai lam gay g6c thi khong duoc nho hen 60° d~
thoat kh6i diroc d~ dang.
Lam duong ong khoi rieng cho m6i tang thi rat tot, nhung lam nhir v~y doi vo! nha
cao tallg Ollg kh6i se nhieu, chiem dian tich trong turrng 1&11,nell thirong cau tao thea
~ A'
kieu 2 orng. Ong thoat khoi chungcho cac tallg va 6ng dung rieng cho tirng tallg. (H3-14)
I
- Duong 6ng thong hoi nen d~t 16 thoat hoi each tran tit 20 - l Scm. Duong thong hoi
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khong chi dat a tirong thea phuong thang dirng rna con co the dat thea phuong ngang tren tran nha, (H3-15).
4.2. Duong Gng do rae :
Trong cac nha cao tang, d~ tao dieu kien thuan lei cho viec chuyen rae a cac tang
tren cao xuong, can thiet ke' cac duong ong d6 rae.
Y! trf 6ng d6 rae nen d*t tai nlurng nut giao thong trong nha nhung kin dao,
Duong 6ng d6 rae yeu cau ben trong phai nhan de khi d6 rae khoi bi tac, nen tot nhat lam bang 6ng sanh, nhom hoac betong due san. Phia tren 6ng d6 rae nen lam ong thong hoi virot khoi mai va tren lam mot bo phan thong hoi dac biet d~ tang them kha nang
thong hoi ur nhien. D~ d6 rac t~i cac tang lam cac ctta d6 rac, ctta mi~ng d6 rac phai kin hoi va Slr dl;lng thu~n ti¢n, phfa duai (tang tr~t) nen co thung rac co banh xe keo ra vao d~ ti~n hot dQn. D~ tiet ki¢m dUOng ong d6 rac ta co th~ lam 2 hQ dung 1 6ng ho*c 1 don nguyen ho*c 1 tang nha dung m¢t dUOng 6ng d6 rac.
V- Cau t~o ~o cua s6 tang ham : (H3-13)
L6 ctta s6 tang ham chu yeu lay anh sang va thong thoang cho tang ham.
Cac giai phap cau t~o :
(H3-15a)
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a nhUng noi khi h~u n6ng ho~c l~nh thl than tUOng ngoai nhi~m Vl;!chiu l,!c, ch!u tac dl;!ng clla mua, gio, con phai co kha nang giu nhi~t, cach nhi~t nhat djnh. G~ch thong thuOng kha nang cach nhi~t kern, muon d~t duqc yeu ctiu cach nhi~t phili tang them chieu day cua tUOng, nhu v~y se tang trQng lUQl1gclla tUOng, tang v~t li~u va anh l)uOng den gia thanh - D~ giai quyet van d~ nay co 2 cach :
- Cai tien v~t li~u lam than tUOng.
- Caj tien cau t~o than tuOng.
VII- TuOng giu nhi~t v.I each nhi~t :
Khe bien dang trong kien true nham d~ phong lun do nhiet dO dong dat va cac nguyen nhan khac lam cho mong, tucng, san gac, mal hinh thanh cac ve't mrt gay anh huong' khong t6t de'n stt dung va lam hir hong cong trinh.
Khe bien dang .gdm cac loai :
- Khe Iun : Khe lun chia cong trinh ra lam cac phan d9C l~p tir mong toi mai d~
d~ phong lun khong d~ll gay pha hoai cong trinh. Vi trf khe lun thircng d~t d cac nci :
+ Nhirng ch6 dat khong ddng nhat co Call tao dia chat thay d6i dot ngot.
+ Cho rna ngoi nha co do cao chenh l~ch va tai trong khac nhau tuong doi 1&11.
+ Ch6 tie'p giap giira 2 phan nha rna thoi gian xay dung khac 1111all.
+ DQ sau va chieu rQng cua m6ng Ian can khac 1111audan de'n hieu s6 lun giira 2 phan qua Ion.
- Khe nhiet d(> : Do su thay d6i ella nhiet dQ lam cho tuong eo th~ bi dan no. Nhirng birc urong dai ean phai lam cho cac khe co dan (khe nhiet do) d~ nrong co th~ dan no nr do duoc, Khe nhiet d¢ phan cong trlnh thanh cac phan nr mai den phdn tren cua mongo V! tri khe nhiet d9 t6t nhat dat b noi bien hoa cua nha. Khoang each giira 2 khe nhiet d9 tu), thea loai ket cau va vat lieu lam nrong rna bien thien tir 15 - 40m. Cau tao khe nhiet de? phai dam bao cac phan bien dang tu do, phai dam bao che mua ... tai cac khe. Khe nhiet d9 va khe hin thuong ket hop voi nhau.
- Truong hop du chieu cao thi Call tao cira s6 nhu binh thircng - Trinrng hop khong du chidu cao thi Co 3 each cau tao.
+ Cau tao tu Idi d tirong be cua sa t~ng tret.
+ Call tao san chim, dung loai n~y tot nhirng hoi date
+ Cau tao 16 cira trong b~ day cua tircng ham - Loai nay it hoac khong nen dung.
VI Cau tao khe bi€n dang : (H3-19)'
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b- Tuong co lop each nhiet d giiia : O? gitra cac lap tUOng g~ch thong thuOng d~t them mQt lap v~t li~u cach nhi~t : Xl than, b~tOng bQt hay lap kh6ng khf ... Hai tam tUOng c6 the Jien ket voi nhau bang sat ho~c g~ch cau.
Chi~u day cac tUOng chiu IlJc thuOng 1/2 - 1 g~ch, can can cli kha nang chju llJc quyet dinh. Nha thap tang c6 th~ lam 1/2 g~ch. DQ day cua lap kh6ng khi vao khoang SOmm khong nen 1611 han vI 1611 han hi¢u qua cach nhi¢t khOng tang nhi~u, rna cac tuOng lien k~t nhau kh6 khan va khong tot, anh hUOng tm kha nang chju l,!c. y~t li~u cach nhi¢t nen lam bang cac v~t li¢u nhy, c6 h~ s6 dAn nhi¢t be, t6t nhat la v~t li¢u vo CO - V~t li¢u cach nhi¢t khong thich hqp vm tUOng Am cho nen cac ch6 Am u6t nen xay tUOng d~c
(h¢ tUOng, xung quanh 16 ctra s6). (H3-26).