• K H O A H Q C C Q N G N G H | : •
K^T QUA THi NGHIEM MO HJNH THUY LU'C AU THUY^N CONG TRiNH LEN - THANH HOA
PGS.TS. TRAN Q U 6 c THlTdNG THS. PH^JW ANH TUAN Vifn Khoa hpc Thiiy lgi Vift Nam
Tdm tdt: Cdng trinh thuy lgi song Len, Thanh Hda Id cdng trinh thdy lgi Idn. co nhiiu hgng m\ic cong trinh nen cdn thiit phdi thi nghiem md hinh thuy luc de kiem chung vdi tinh todn. Bdi viit neu tdm tdt kit qud nghiin cuu thi nghiim di chgn ket cdu du thuyin sdng Len hgp ly.
Abstract: Len headwork of water resources project is large structure, consisting of various components. Therefore, it requires to conduct physical model tests in order to verify with detail design. In this paper, summary of experimental results on physical model are being presented, of which these data will be served for reasonable selection of structure in Len navigation lock.
Key word: navigation lock, model test, reasonable structure I. GIOI THIEU CONG TRINH VA
NHIEM VU THi NGHIEM 1, Nhi?m vu cua cong trinh
fl, Cy^m cdng trinh: ndm tren sfing Len tgi vi tri ben dd Ghenh thudc xd Da Ldc, huyen Hdu Ldc va xa Nga Thuy huyen Nga Son, each cua bien khodng 3,5km ve phia thuang luu.
b, Nhi^m vyi cua cdng trinh
Ngdn man, gid ngot d8 dam bao ngudn nudc cung cap nudc cho 23 255 ha dat canh tdc va nudi trdng thuy san; cap eho sinh hogt, ch3n nudi vd cac ngdnh kinh te khae thugc cdc huy$n Hgu LQC, Nga Son, Hd Trung, Bim Son hogt dpng fin dinh; ung phd vdi bifin doi khi hgu vd nudc bien ddng dnh hudng dfin ngufin nudc cung cdp cho khu vuc du an. Cy the nhu sau:
- Di?n tich ddt canh tdc: 18 821 ha;
- Dien tich nudi trfing thuy san: 4 434 ha;
- Cdp nudc cho sinh hogt: 613 344 ngudi;
- Vat nudi cdc loai: 458 761 con;
- Dien tich cdc khu cdng nghiep cae loai: 1 619 ha.
c. Cap cong trinh vd cdc hang muc - Cdp cdng trinh: Cap II
- Cdng ngdn man, giu ngot:
• Kifiu logi: Ddp tni dd
• Chieu rong thdng nudc: 03x40m = 120m
• Cao trinh ngudng cfing: -5,00 m.
• Cao trinh dinh tru pin: +4,00m
• Cao trinh dinh eua van: +2,60 m.
• C6ng cd ket eau bdng BTCT, xd ly nin bdng CQC BTCT 40x40cm, chiSu ddi 12-24m.
- Au thuy en:
• Cdp giao thfing dudng thuy: Cdp I
• Chieu rdng au thuyin: B= 14 m.
• Chieu dai hiiru ich budng du; L=150m;
• Cao trinh day du thuyin: -5,0 m;
• Cao trinh dinh tru pin du: +4.00;
• Hinh thdc cdp nudc: Phan tan bdng cdng ngam;
• Cao trinh dinh eua van: +2.60;
• Logi cua van: Cua chu nhdn 2 ldp;
• Thiet bi dieu khien cua van au:
Xylanh thuy luc - Cau giao thfing:
• Tdi trong cdu: HL93
• Ddm c^u:
Dam thep lien hop SCP;
• Be rdng nhip cdu: 45,0(hn
• Cao do ddy ddm cdu: +12,60m
72 TAPCHfTAl NGUVeNNl/CSCSO 1-2019
• KHOA HQC CONG NGHE •
• Chifiu rdng cau: B= 7,5 m.
• S6 luong nhip cdu: 10 nhip.
• DO dfie dgc cdu 2 ben bd: i=6,0%;
2. Muc dfch nghien cvra mo hinh thuy luc Thi nghiem mo hinh thdy lye dau moi Lhn nham:
- Kiem tra khd ndng thodt nudc qua cdng trinh;
- Kiem tra tinh hinh thuy lye, tieu ndng phdng xdi cua do dn thilt kfi;
- De xuat phuang dn sua d6i, dilu chinh lgi cdc hang muc thiet ke sao cho cd Igd vl m^t thuy luc di den hodn thien thilt kl cdng trinh;
- Ddnh gia che dp thdy l\rc bdt lgi khi cda van ggp s\r cfi (bi ket) trong giai dogn vgn hdnh khai thdc gay mat on djnh cho cfing trinh;
- Cung cap ca sd khoa hgc cho tu van thiet kl trong giai dogn thiet kl kf thuat, thi cfing.
Ket qud nghien cuu thi nghipm mfi hinh vgt ly sS ly gidi rd han cdc vdn dl tinh todn ly thuylt. Su kit hap gida If thuylt vd thi nghiem mfi hinh se giup cho Tu van thiet ke.
Tu vdn thdm tra ky thuat, Chu ddy tu va cdc chuyen gia ky thudt lya ehgn dugc ket cau vd qui md cae hgng myc cdng trinh ddm bdo ky thuat, an todn cao trong qud trinh xdy dyng va khai thac sd dyng, ddp ung myc tieu, nhipm vy cua cfing trinh mOt cdch cd hi$u qud nhat, dac biet la au thuyen.
II. KlfcT QUA THI NGHIDM 1. M6 hinh hda
De dgt dugrc myc tieu vd ddp dng yeu cdu thi nghifim vdi cac ndi dung ciia chu ddu tu, thi md hinh thi nghiem thuy lye dugc chpn Id md hinh tong thfi chinh thai Idng cimg (Idng khong xdi dugrc), cy thfi nhu sau:
a, Chpn mo hinh:
- Mfi hinh dau mdi cong sdng Ldn la mo hinh tdng the ehinh thdi Idng cdng, t^ 1^ md hinh l/40(dnhlva2)
b, Pham vi md hinh:
Kich thudc thuc tl: Ddi x rpng x cao (LxBxH)=1600x640x40(m)
Kich thudc mfi hinh: Dai x rpng x cao (LxBxH)^0xl6xl,0(m)
i ij fc •.
Anh 1: Md hinh tdng the Len - nhin tir thirang luu Anh 2: Md hinh cdng vd du thuyen Len 2. Ket qua thi nghifm phuong an thilt kl Thiet ke cua vdo vd eua ra au thuyen vdi gdc u, cdu tao cua vdo vd cua ra du thuyen a ^ 45" (hinh 1 va 2, anh 3 va 4)
TAP CHI T A I NGUYEN Nl/(3C S(5 1-2019 73
• KHOA HQC CONG NGHf •
' I ' l l 1 1 1 1
1 1 1 1 1 1 1 U i R O 1 1 1 1 1 ' 1 1 1 1 1 1 i e = i 5 i j 1 1 1
L^A^j-uj. .^'.^Ai' ^ ' 1' 1' 1' 1' iJd:-^*ldJJEE:'--*l^5iT-'-T^T-4 ' 1 ' 1 ' 1
j|KftftSggSi333
•(y<y<y^cy<>£
^Gtc cita vao><><>
t K 1 1 1 1
' i , " i ' i ' i ' i "
\ / \ /
' I ' I ' I ' ^ S O J I ' I ' I ' I V ^ S
^ ' i ' i ' i ' i ^ ; ' : ; ^ F f e % E ^ ^
1 ' 1 1 1 l ^ A I > - , . L 1 J L ^ U I ' 1 1 1 1 1
1 1 1 1 \ A-f 1 \ \ I A I 1 1 1 1 1 1 ( l 1
•-tWiW'Gdc cda ra "tH-fc
=H=m du 45'* ii=c>
^ ^--^^-^4^^i|4lt^f^-jw<^
Hinh 1 vd 2. Gdc md tudng cua vdo vd cua radu a = 45
Anh 3 vd 4: Gdc tirdng ben cua vdo du vd cua ra du a 45 b. Kit qud thi nghidm
- Khi md c6ng vd du thuyen
Ddng chay qua cdng Id chu yeu, ddng chdy qua au thuyen nhd, nen che dp thuy Ivc trong du thuyen khfing phdc tap.
Ddng qua du thuyen phdn bd kha deu, ddng em. 6 thupng vd hg luu du, tai khu vuc md rpng mang du, luon cd xoay cupn nhp, pham vi rpng B=8-12m; ddi L=40-50m; Pham vi xoay d hg luu Idn hon d thugng luu. Cudi khu vuc tudng hudng tdu (culi pham vi nao vet), do dia hinh ty nhien chua dugc ngo vet, nhd ra nhu bdi nho chdn ddng chdy mpt phdn tao nen ddng qudn ben bd trai, mgt phdn ddy ddng tu phia trdi hudng dan ra gifta sdng. Cdc cgt hudng tau tao
thanh cdc gdn nudc.
Van tfic ddy ddng chdy trong au Idn nhdt khodng l,2m/s.
Chieu cao sdng nhd khodng 0,1m.
- Khi chi md du thuyin.
+ Thu&ng luu vd than au: Vdi Qmaxi% - 308m''/s, Zhi=0,61m ddng qua au chdy xiet, nudc chdy dgng sdng keo dai td dau tdi cudi du, chilu cao sdng khodng 0,5^0,7m. Ddng qua cua vdo vd cda ra au thuyen cd co hpp Idn. Do anh hudng cua co hpp, m\rc nudc d cda vdo hg thdp h=0,9-^l,4m, chfinh l^ch ben trai Idn hon ben phai. Muc nudc d cua ra hg thap h=0,6m.
Mang thugng luu au thuyin cd ddng quan, xoay cu0n Idn.
74 TAP CHf T A I NGUYEN Nl/(5C SC5 1 -2019
• KHOA HOC CONG NGHE • + Vdi Qio%=19W/s, Zw-™„=-l,03m: 6 nua
dau au thuyfin dfing van chay xik, dang song, chieu cao song Ichu vuc dSu au sau cua vao la hs= 0,32m.D6ng qua cijra vao §u thuyfin c6n co h?p Ion, mure nuoc a c\la vao ha thip h=
0,8-^l,32m, CO h?p ben trai ion ban ben phai. CJ niia cufii au thuyen, song trong fiu giam d ^ . Co h?p tai cira ra au thuyen Ichfing Ifim, muc nuac ciia ra h^ thSp Idioang 0,4m. CJ mang thupng luu du thuyen co dong qudn, xoay euon, nho hon voi Q=308mVs.
-K3 hsi lim au: Mang h^ luu au thuyen co khu qu3n, xoay cufin pham vi rfing B=l(H-14m; dai L=36-i-50m. Dong trfin kfinh d ^ g ch4y song, dong cfin xifit vk hircmg thing vao phia hb ph^, khu v^c each tim cfing khoang 420m, dfing tap trung ben ba ph^, theo Igch sau ciia long dan tu nhien. Sfing tren sfing khu vuc h? luu cfing trinh khoang 0,16-0,20m.
-I- van t6c ddy lan nhit; Q = 308mVs, v« 4,4 m/s; Q =199mVs, v = 3,4m/s
Mo ta dong chay qua au a cac anh 5,6,7 va 8.
Anh 7. Dong ciia ra du chdy song huang thdng sang baphai
Anh 8. Xoay cudn a mang ha luu du
- Nhan xet va kien nghi: nghi nhu sau:
Qua thi nghifim phuang an thifit kfi vfi au + Nhan xet:
thuyfin, chiing toi co mot so nhdn xet va kien Do anh huang ciia goc ma cua vao, cua ra a TAPCHfTAlNGUYeNNUOCSO 1-2019 75
• KHOA HQC CONG NGH|: •
Idn nen sinh ra xoay nudc, ddng qudn d cua vao va ra. Ddng thdi cd sdng Idn khoang gan Im d trong du thuyin, cda vao au cd bac thut Idn khoang 1,40m, cua ra au cd bdc thut khoang 0,6m. Van tdc ddy Idn nhat khoang 4,40m/s.
Chi dg thuy luc phuc tap se gdy ra bdt Ipri eho tau thuyen qua au, ddc biet Id xoay nudc, sdng, bdc thyt cung nhu van tfic ddng chdy Idn la nhihig yeu t l can hgn che khdng duac xdy ra khi thiet ke du thuyen.
Do dd da kiln nghi mdt sd van de sau:
+ Kien nghj
• Bgt mai bd ben phdi thugng luu de ddng
chdy thudn.
• Thu hep gdc cda vdo vd cda ra du thuyen, ed thi tu 45" xufing 17°
• Nen xd luu lugng nhd khoang 199 m^/s qua au.
3. Ket qud thi nghidm phinmg an sfra doi a. San doi goc cira v^o %^ cim ra cua au tbuyat Do gdc md cda vdo va cua ra cua du thuyen Idn (45^) nen dnh hudng tdi che dg thuy lye cua du thuyfin. Qua thd nghiem da thong nhat vdi ca quan thilt kl thu hpp gdc md eua vdo vd eua ra cua au thuyen tir 45 xudng 17 .
Mfi td eua vao va ra au thuyen (hinh 3 va 4, dnh 9 vd 10)
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Sira goc cua vao autu-45<'-^17°
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Hinh 3 vd 4. Goc md cua vdo vd cua ra du a =17^
Anh 9 vd 10. Goc md cua vdo vd cua ra du a =17^
b. Kit qud thi nghiem - Khi md cdng vd du thuyen:
Tuong tu nhu phuang an thiet kl ddng chdy qua cdng Id chu yeu, ddng chay qua du thuyin 76 TAP CHf TAI NGUYEN Nl/OC S6 1 -2019
' KHOA H p c CONG NGHE • nhd, nen che dg thuy luc trong au khdng phuc tgp.
O mang cua vao vd cua ra au cd khu ddng qudn nhe, pham vi ddng quan nhd hon phuong an thiet kl nhilu. Cdc cgt hudng tau tao thanh cac gan nudc, tuy nhien chilu cao chi bdng 2/3 chilu cao eua phuang an thilt kl.
Vdn tdc day ddng chdy trong du Idn nhat khodng l,00m/s.
- Khi chi md au thuyin:
+ Cua vao du: Hinh thdnh co hep idn, tgo bac thut hg thap khodng 1,26m; trudc cua vao au khdng xuat hien ddng quan, xoay nudc. Ddng CO hep giam so vdi phuang an thiet kfi.
+ Than au: Ddng qua au Id ddng chay xiet, dang sdng, sdng giam ddn theo chieu ddi au;
chilu cao sdng gidm ddn ve phia cda ra au.
+ Cua ra du: Co hep tai cua ra du nhd, muc nudc tai cda ra tgo bac thut ha thap khoang 0,42m.
Sau cua ra du, ben bd trai tin tai ddng vgt nhp.
+ CJ ha luu du: Ddng tren k€nh dang chdy sdng nhp, ddng chu luu bdm theo dudng cong bd trdi.
+ Vdn tfic day ddng chay trong au vdi Q=199mVs,v«3,40m/s.
Md ta ddng chdy qua du d cdc dnh 11, 12, 13 vd 14.
Anh 11. Dong co hep qua cua vdo du Anh 12. Dong chdy dgng song dgc theo todn du
Anh 13. Ddng chdy d hg luu sau cua ra du Anh 14. Ddng qudn hg luu sau cong III. THAO LUAN VA KET LUAN trinh du thuyen Len chung tdi cd mot sd nhan 1. Nhan x6t xet nhu sau:
Qua thi nghiem mfi hinh thuy lye cdng - Gdc md cua vao va cua ra au thuyin theo
TAP CHfTAl NGUY6N N U < 5 C S 6 1-2019 77
• KHOA HQC CONG NGH|: • thiet ke Idn (a =45 ) nen gay ra che do thuy l\rc
phdc tgp d long du, thupmg va hg luu au: Sdng trong au Idn khodng 0,70m, xudt hipn bac thut d cua vao au (khoang 1,40m) vd cua ra du (khoang 0,6Dm). Cd ddng qudn, xody cudn ... d thugng va hg luu au thuyen.
Vgn tdc ddng chay trong du Idn (vdi Q = 308mVs, Vd « 4,4m/s; vdi Q =199m^/s, Vd ^ 3,4m/s). Do do cdn chpn gdc md cua vdo va cda ra du hgp ly, dd tiln hanh thi nghiem nhieu phuang an vd chpn gdc md a =17**.
Vdi gdc md cua vdo va cda ra au a=l7 da cdi thipn che dO thuy l\rc cua au, nhu: tript tifiu ddng qudn xody cudn d cda vao va ra du, chieu cao sdng trong au gidm so vdi phuang an ban dau.
Vgn tdc ddng chay trong Idng au (vdi Q = 199mVs,Vd« 3,4m/s)
Vdi vgn toe day nhu vgy Idn ban vgn tdc xdi cho phep cua vung cong trinh [v] kx = 0,95m/s, neu dung au thuyen de xa bun cat Id dam bdo vdi Q = 199m^/s, Vd « 3,4m/s > [v] kx = 0,95m/s.
Khdng nen xa luu lugng Idn hon 199m^/s se gay b4t lgi cho cfing trinh.
Ket qua thi nghipm sua ddi da dap ung yeu cdu vfi lam vi^c cua au thuyen la khdng cd ddng quan xoay cudn d cda vdo vd cda ra au thuyin gay bdt lgi cho tdu thuyin qua du.
Tuy nhien thi nghipm cdn it npi dimg vd cdc md hinh cue bp. Xin neu thi nghipm 1 du thuyen cua Trung Quoc de tham khdo.
2. Thi nghipm md hinh thiiy lure au thuyen sl 2 Cat Chau Ba, Trung Quoc [91
a, Gi&ithifu chung
Tram thuy dipn Cat Chau Bd cd chilu ddi budng au 280m, rdng 34m, chilu sdu nudc tren ngudng la 5m, trudc mdt cho qua dpi tau cdng 3xl500t, trong tuang lai cho qua dpi tdu cung
4x3000t, chfinh Ipch muc nudc Idn nhdt Id 27m, lugng chuyin nudc cua buong au 287.000m , thdi gian nap (thdo) nudc budng au yeu cau Id 12-15 phut, luu luang tue thdi Idn nhat nap nudc buong du Id 800m^/s. Day Id Idn dau tifin d Trung QuIc thiet kl va xay d\mg au thuyin loai Idn vdi quy md nhu vay. Phdi nhd vdo thi nghipm md hinh, di sau nghien cuu tim tdi, phdt trien van dfi va gidi quyet vdn de.
Viec thi nghifim mo hinh thuy lye au thuyfin sd 2 Cat Chau Bd dugrc tifin h^inh trong 10 nam (bdt ddu tu ndm 1971) da tien hanh cac cdng tdc nghien cuu thi nghipm nhu: mo hinh chinh thi he thfing chuyen nudc au thuyen, md hinh eye bg, md hinh thuy lye cda van chuyen nudc au ...
lan lugt dd ldp nhieu ban bdo cdo nghifin ciJru thi nghipm, da gidi quyet kip thdi hang logt v ^ dl ky thudt trong thilt kfi vd thi cdng, dam bdo cho cfing trinh dupfc tiln hdnh thuan loi. Td th^g 5 den thang 6 ndm 1981, du thuyfin s6 2 bdt dJiu van hdnh thd, da tifin hanh mpt sd quan trdc thyc te ve m^t thuy luc, thdng 2 nam 1984 lgi tiln hdnh m§t sd quan trdc thuc tfi, kfit qud sa bd cua cdc quan trdc thyc te chdng td kit qud nghifin cdu thi nghipm Id ddng tin cdy, du thuyen vgn hdnh an toan.
6, Thi nghidm mo hinh chinh the h$ thing chuyin nudc au thuyen
Muc dich ciia thi nghipm md hinh chinh the he thdng chuyen nudc du thuyfin la tim ra sy bfi tri he thfing chuyin nudc thich hpfp. Yeu cau ddi vdi su bo tri h? thfing chuyin nudc cua au thuyen sd 2 Cdt Chdu Bd Id:
- Cda vao vd cua ra khdng dugc sinh ra xody nudc cd hgi;
Tdu thuyen qua au, d trong dudng dan thugng, hg luu vd trong budng au, cSn cd dilu kipn do ddu tfit, luc bupc cap hudng dpc Idn nhdt cua nd khdng dugc vugt qud 49.03KN (5t), 78 TAPCHfTAl NGUYEN Nl/OC S6 1-2019
• KHOA HQC CONG NGH$ •
lye huge cdp hudng ngang Idn nhdt khfing vugt qua29.12KN(3t);
- Thdi gian nap (thao) nudc budng au la 12 - 15 phut, ddng nudc vdo budng du khdng dugc trfin nhilu khi;
De nghien cuu thi nghiem da xdy dyng md hinh vdi ty 1^ 1/40.
- Ket qud thi nghiem:
+ Lua chpn hp thdng chuyen nudc:
Trong hai budng au giap nhau, dd tien hdnh thi nghiem 8 phuang an bd tri hp thdng chuyfin nudc vdi hinh thdc khac nhau, cudi cung da chgn hinh thuc cua vdo hudng bfin cd nhilu lo nhanh dp dung cho cda vao cua he thdng chuyen nudc, cdn vipc thdo nudc cua hp thong chuyfin nudc thi dung hai hanh lang thdo nudc d ben trdi, ben phai. Trong buong au thi dung phuang dn hanh lang nhdnh ngang, dgc.
Cach bd tri hp thong chuyin nudc dang tren cd nhihig dac diem nhu sau:
• Hdnh lang nhanh trong budng du dugc chia lam 3 nhdm: Hanh lang nhdnh dgc trudc, sau, va hanh lang ngang d gida, td do dua ddng nudc thdng qua 228 lo nhdnh ben, di qua mang hd tieu ndng, phan bo deu trong todn bp budng du. So vdi each bl tri da dimg d nudc ngoai, lam cdc hdnh lang nhdnh ngang so le nhau d trong khodng 1/3 gi&a cua budng au (nhu au thuyen Holt d My), thi nd cd uu diem la ddng nudc phan bd trfin dipn rgng; va so vdi each bo tri cdc hanh lang nhdnh ngang nhu kieu phdn nhdm (nhu du thuyin ICE Harbor d M^) thi nd lai trdnh dugc nhugc diem Id, neu md van d mgt bfin, hodc md khdng ddng bg van d hai ben, thi cd thi gay ra luc tac dung cua ddng chdy hudng dgc qua Idn.
• Do 5 cda vdo cua hanh lang nhdnh dugc phan bfi trong phgm vi chilu ddi 70m cua hdnh lang chinh d moi ben phdn gida budng du, nhd
dd cd the gidm dugc chieu cao cua hdnh lang nhdnh, thda man dugc yfiu cdu cda thiet ke va thi cdng Id cfi gdng giam khdi lugng ddo da goc d hulng au, tilt ki$m 6ka tu cdng trinh. Tuy nhien, hinh thuc bd tri nay vin cd the sinh ra lye tdc dyng nhdt dinh cua sdng trong thdi gian bat ddu ngp nudc vao budng au, nhung lye dd khdng Idn, khdng cd tdc dung khong che.
+ Ddc tinh thuy Iyc chuyen nudc budng au:
Trong thi nghipm, da do thdi gian nap (thdo) nude buong du vdi cdc td hgp muc nudc khdc nhau, va thdi gian md van khdc nhau.
Thdi gian chuyen nudc ty lp thudn vdi thdi gian gian md van, t;y' so cua hai thdng sd Id mpt hang s6 nao dd, tdc = k. Dfii vdi h? thing
AT;
chuyin nudc nay, tu cdc sd li^u trfin day, bSng phuong phap do gidi, tim dugc k=0,552 (ngp nudc hai ben). Khi chenh l^ch muc nudc thilt ke Idn nhdt H=27m (myc nude thugng luu 66.0m, myc nudc ha luu 39.0m) xdc dinh dugc dudng d^c tinh thuy lye chuyin nudc buing du.
Khi thdi gian md van hai bfin la 5 phut, thdi gian ngp nudc buong au la 12.17 phut, luu lugng ngp nudc Idn nhdt la 730 m^/s, hp sl luu lugng Id 0.74, thdi gian thao nudc bufing du la 14.77 phut, luu lugng thao nudc Idn nhdt Id 625 m^/s, hp sd luu lugng la 0.565. Sau khi tinh todn hi^u chinh cac thdng sd thuy lye d md hinh va nguyen hinh, cho thdy tdng the so sdc cdn dgc dudng cua nguyen hinh gidm di 0.38 so vdi md hinh. Cd tdng hp sl sue cdn thyc do cua mfi hinh la:
£5 = 1 1
- = 1.826 (1) K (0.74)-
Do do, tfing h$ sfi siic can cua nguyen hinh se la:
SS, =1.826-038 = 1.446 (2) H? s6 luu lupng ciia nguyen hinh se la;
TAP CHl TAlNGUYtN NUdc S6 1-2019 79
• KHOA HQC CONG NGHE •
= 0.832 (3)
Do md hinh khong trdnh khdi rd ri nudc, cho nen tri s6 qudn tinh cua mfi hinh thudng thien nhd, khdng nhu tinh toan theo cong thdc
d = — ^ , trong do, cr la dien tich van, Q Id dien tich vung nudc budng du, Lnp la chifiu ddi tinh ddi cua hanh lang (266.7m), tim dugc
(0.832)'x55.0x266.7
d = ^ - = 0.94m
10836
Sau khi xdc dinh sd p vd d, cd the tinh todn chinh xac ngay dugc thdi gian chuyfin nudc, hi sd T, ung vdi thdi gian md van va chenh Ipch myc nudc bdt ky. Cfing thuc tinh todn nhu sau:
_ 2Q(M+d-yfd)
\-Ktv (4) ptu^fZg
Tinh todn dugc T=10.47 phut, nit ngan 1.7 phut so vdi mfi Wnh. Tilp theo cd the tinh dugc luu lugng Idn nhdt nap nudc budng au la 800 m^/s.
Tdc la, khi myc nude trong budng du dang Ifin din cao dg thim ngang, thi myc nudc budng au se xd vl phia thim, lam cho dgi tdu 4x3000t phdi chiu lye sdng rat Idn, ma dd khdng phai la loi cua bdn than h? thing chuyfin nudc. Do do, tudng che thim rgng thdng dung dugc sua thdnh kilu mdi dfie hinh tam giac (nhin tir trfin xufing).
Chilu dai thim ngang rut ngdn cdn 2.7m (tu chan nudc day cua chu "nhan" den ddu cudi them ngang), dieu kipn dau do da dugc cdi thien. Lye neo huge nhd ban tri sd cho phep.
- Ngodi thi nghipm tren cdn thi nghiem ede ndi dung sau:
+ Nghien cuu thi nghipm ciia van chuyin nudc:
• Thi nghipm chpn loai cda van
• Thi nghiem lye ddng md cua van + Thi nghipm dieu kipn dung dd cua tdu thuyen qua du;
+ Xdc dinh lye khdp gdi va mach dgng khdp gfii;
+ Xdc dinh phSn bd dp Iyc d thdn cua van;
+ Thi nghipm md hinh giam dp d cda van;
+ Thi nghipm lye ddng md cda chu "nhan"...
+ Kilm chdng so sanh thi nghipm vdi thyc te van hdnh du thuyfin.
3. Kit lugn
Qua thi nghipm md hinh da sda ddi ket cdu cua vao vd ra cua au thuyen cdng trinh Len nhu hinh 3 vd 4.
Kit cdu sua dfii dd ddp ung yeu cau ve che do thuy lye Id khdng xuat hien ddng quan, xody cudn d cua vao vd ra du thuyen de thugn lgi cho tdu thuyen qua au.
Tuy nhien qua tham khdo tdi lieu thi nghiem du thuyen sd 2 Cdt Chdu Bd cua Trung Qudc, de nghi cdc CO quan qudn ly nfin cho thi nghipm nhieu md hinh eye bg de phuc vu cho thiet ke vd thi cfing du thuyin Len ndi rieng vd cac cdng trinh thuy Igi, thdy dipn ndi chung dugc hipu qud vl kinh tl - ky thugt ban.
TAI LIEU THAM KHAO 1. Trdn Quoc Thudng, Thi nghiem md hinh thuy luc cdng trinh, NXB xay dung, 2005.
2. Tieu chuan qudc gia TCVN 9147:2012, Cdng trinh thuy Igi - Qui trinh tinh toan thuy Iyc dap tran.
3. Tieu chuin Vipt Nam TCVN 8214:2009, Thi nghifim md hinh thuy Iyc cdng trinh thuy lgi, thuy dipn.
4. Thi n g h i ^ mfi hinh thuy lye au thuyen Kinh Lp, Vipn khoa hpc thuy lgi VietNam, 2010.
5. Thi nghipm md hinh thuy lye au thuyen Cdu Xe, Vipn khoa hpc thuy Igi Vipt Nam, 2013. v.v.
Ngudi phdn bi$n: PGS.TS VG Hoang Hirog Phdnbmxong: 11/2018
80 TAP CHf T A I NGU Y E N N U C C S 6 1 -2019
