Tgp chi Khoa hoc - Cong nghe Thuy sdn THONG BAO KHOA HQC NGHIEN ClTu TOI iTU HOA KET cAu TAU VO THEP SlT DUNG KET HOP PHU'OfNG PHAP MAT CAT VANG VA TIM KIEM TRlTC TIEP OPTIMIZATION OF STEEL SHIP STRUCTURES BY COMBmiNG THE GOLDEN SECTION SEARCH METHOD AND DIRECT SEARCHING AiGORITHM Phgm Bd Linh' Ngay nhan bai 25/6/2014; NgAy phan bi?n thong qua 26/8/2014; Ng^y duy?l dang: 01/12/2014 TOM TAT Trong thiet ke ket cdu tau v6 thep hi4n thuang tinh theo quy phgm ngudi thiet ke thuang g^d thiet truac cdc hdi thuac cua ket cau vd tien hdnh Hem tra theo cdc yeu cdu Phuang phdp ndy nghiem nggt nhung kit cdu thdn tdu duac thiet ke chua a dgng toi uu Tren ca sa ket hap phircmg phdp mat cat vdng vd thugi loan lim kiem true tiep, bdi bdo trinh bdy ket qud nghien cim thiet ke toi uu ket cau tdu v6 thep nham tiet hem vdt lieu, gidm trpng lu(mg kit cdu qua co the ndng cao tinh ndng hdng hdi cua tdu Tir khoa: loi uu hoa, mgt cdt vdng, tim kiem true tiep ket cau tdu, toi uu kit cdu ABSTRACT In the structural design, steel ship structures are now commonly calculated by rules of norm Designers usually predefine the sizes of the structure and conduct the verification according to the requirements This method is strict but the designed structure is nonoptimal shape Base on the golden section method and direct searching algorithm, the structural optimality of steel ship can befound in order to save materials, reduce structural weight as well as to improve the performance of maritime vessels Keywords: optimization, golden section, direct searching, structural optimality I DAT V A N Dt Tdi uu hda kit cau Id mot nhdng bdi toan quan trpng qua trinh thilt k l tau thuy Hidn nay, k i t c l u thdn tdu chu y l u duac tinh chpn theo ede yeu eau eiia Quy ph$m ding tdu hien hanh [2] Thvc le nhan thay, viec linh theo Quy pham thudng phdi chip nhdn t i n kdm vdt lidu vd tdng trpng lup-ng eua tdu vi ban than k i t eau chua d dgng hp'p ly nhat Chinh vi t h i , cae Quy pham tinh k i t eau than tdu hidn d i u cho phep vd khuyin khich ngudi thiet ke tinh ehpn lal kich thudc cdc k i t eau thdn tdu theo eac phuang phap mdi, trdn ca sd ddm bdo d | ben vdi chi phi vdt lieu Id it nhit Thilt k l t i l u'U k i t clu khdng chi cho phdp tilt kiem vdt lieu, gid san phim ma cho phdp ndng eao cdc tinh ndng hdng hai ciia tdu, chdng hgn nhu edi thien toe dp nhd gidm bdt trpng lu-png tdu [4] Bdi loan toi uu ndi chung dupe phdt bieu nhir sau[3,8,9]T)m tdphp'pcdcgidtriX = (x,,Xj \) d l eho ham so Z= f(x,, Xj, x j dgt ci^e bi, dong thdi thda man cdc dilu kien sau: (i = ^ n) (-1 Trong ham Z gpi Id hdm myc tidu dilu kidn (1) Id he gom nhilu hdm rdng buOc Ridng dli vdi bdi todn toi uu h6a k i t c l u , hdm myc tidu ZcdVnk Id trpng ludng gid thdnh, thdi gian c h i tao eua kit elu Cdc hdm rdng bu$c cd the Id v l dO ben, dO edng, dO I n ^ n h hodc dieu kipn cdn bang, x'^ ''max '^ 9'^ *''! "^^ "^^* ^^ ' ° ' " "^^* ^'^^ *^i^n thilt kl, ' ThS Piiam Bd Linh' Khoa Xay dgng - Tordng Ogi hpc Nha Trang 46 • TRLTONG OAI HOC NHA TRANG ^ [I < ' t , i, So 4/2014 Tgp chi Khoa hoc - Cong nghj Thuy s cd the la chieu ddy; chiiu eao song chinh; song phy; xa dpc mgn; chieu day tdn v6 trong; vd ngodi; tdn hdng Khi dd, tdp hdp gid in X = (x,, x, , xJ thda man lat ca dilu kign rdng bu|c gpi Id mpt nghigm dd nghigm Idm hdm Z dgt cyc trj (cyc dgi hay cyc tilu) Id nghidm t i i uu Miin tgp hp'p tat ca nghigm gpi la mien nghigm hay khdng gian bien thilt k l [3] Cac phuong phdp t i i uu hda hidn tgi cd the duvc chia thdnh ba nhdm: phuang phap tim kiem (Heunstic methods), phuang phdp quy hogeh todn hpc (Mathemabeal programming models) vd cac thudt todn i l l uu dua tren nin tdng cua sy lien hda [5] Nhdm phuang phap tim kiem (Phuang phdp khung, phuong phap dO die, phuang phdp gradient ) xuat phdt tif mpl nghigm ban dau tu tim kilm cdc nghidm cho gid tri hdm myc tieu tot han tren ca sd phdn tieh ede ham rang bupc Nhom ndy yeu c l u phai cd hdm rdng bu|c hfdng minh vd thudng chi eho nghiem toi uu eye bp, toe dp hpi ty phu thupc nhilu vdo nghidm ban d i u [1, 3,8,9,5] Nhdm phuang phdp quy hogeh todn hpe (Phuang phap d l thj, phuang phdp dan hinh, ) phil hap cho bdi todn toi uu tuyen tinh, d l i vdi bdi loan toi uu hda phi tuyen nhom ehii yeu eho nghiem t i i uu cyc bo Cung nhu nhdm phuang phdp tim kiem, nhom yeu eau phdi ed ham rdng budc tudng minh [3,8.9] Nhdm cdc Uiudt todn dya trdn n i n tang tiln hoa (giai thugt di truyen - GA tiln hda - DA, md phdng qud trinh ii - SA ) co uu diem khdng can cae ham rdng bupc tudng minh nhung d l tim dupe nghidm i l l uu loan eye thi c l n so iln ldp rit Idn, thong thudng nhdm phuang phap dupe dilng d l lya ehpn nghiem gan vdi nghiem t i i uu va dung nghiem dd lam nghigm ban dau cho cdc phuang phap khde [8, 6j Trong bai todn thiet k l kit c l u tdu thing Ihudng phai lua ehpn cdc thdng so ciia kit eau de thda mdn dd b i n ehung va dp b i n eye bp theo yeu cau Quy phgm, d nghidn ciru Igp tmng vdo toi uu kit d u theo dp ben chung cua thdn tau Doi vdi bai loan vigc tim mOt hdm rang bupc tudng minh r i t khd khan va khdng khd thi, nhu vgy de xac ^ n h cae thdng so toi \iu cho k i t cau ehi eo nhom phuang phdp dya tren nen tang lien hda Ngoai cung cd the eho thu tat cd cdc phuang dn d i u vdo (thudt todn tim kilm tryc tilp), tif dd phdn tich k i t c l u vd tim nghi$m i l l uu Bdy khdng phai la phuang phap toi uu nen khit lup-ng tinh todn Idn, thdi gian tinh todn rit Idu nhung no cho phep tim nghigm loi uu loan cyc vd khdng c l n ham rang bupc tudng mmh Nhu vgy, de gidm thdi gian tinh loan, tang l i e dp hpi ty cln phdi cai tiln thugt todn Nghidn euu k i t hpp phuang phdp mgt eat vdng (Id mpt thudt toan diing d l tim nghigm ham mpt bien) vdi thugt todn tim kiem true tilp vdo vigc gidi bai loan t i l uu kit eau tdu vd thep se cho phdp lim nghigm toi uu nhanh chong, tif dd gidi quylt bdi loan toi uu hda k i t cau tdu thdi gian nhanh han vdi dp chinh xae eao nhat II OOl TLfgNG VA PHU'aNG P H A P NGHIDN CLTU Odi tucmg nghien cihi Doi tuang nghien euu Id thilt k l k i t cau t i i uu ddm bao dp ben chung ciia tau chd hdng rdi 2000 DWt Tong cdng ty Cdng nghigp tau thuy (CNTT) Nha Trang ddng nam 2001 theo quy pham phdn cap vd ddng tdu bien v6 Uiep TCVN 6952 : 1997 vd dupc dang kilm Viet Nam kiem duyet [2 7] Phuo'ng phap nghien cuti 2.1 Phifong phap phan tich kdt ciu Hidn cd hai nhdm phuang phdp d l xac dinh dupc dd bin chung ciia vd tdu dudi tdc dyng cua mo men uln dpc Nhdm phuang phdp thu nhat la xdc djnh Infc tilp (Phuang phap Caldwell, phuang phap phan tu huu han phi luyln) vd nhdm cdn lal la xae dinh bang phan tieh tang dan (Phuang phdp ISUM, phuang phap Smith) [11-14] Phuang phdp xac dinh tryc tilp la phuang phap tinh loan xdc ^nh ung suat tung phan l u eiia k i t cau vd so sanh vdi dng suat cho phep cua vat lieu, nhdm phdn tich lang dan xuat phat td bien dang eua kel eau va cho kit c l u biln dgng tang dan cho den bj pha hOy td xac dinh tai trpng gay bien dgng Idn nhat ma kit cau co t h i dap dng Tieu bleu eho nhdm phuang phdp thir hai la phuang phap noi tieng ciJa Smith [14] Rat nhilu cdng trinh nghien cuu da cong bo v l vide ddnh gid bin chung cua tau bdng phuang phdp Smith vd phuang phdp da dupc ddng kilm I ACS chip nhdn [10] vi vdy, qud trinh tinh todn t i i uu, nghien cdu sd dung phuang phdp Smith d l phdn tich k i t cau tdu de kilm tra dilu kien rdng bude eua bdi todn 2.2 Md hinh tinh fr T "1„ '±_ t^ - -ir ^ 'L J~ ' ' " -ft - ? " "7 -^^Jj Hinh Mat cat ngaog giira tau 2000 DViTT TRUONG DAI HOC NHA TRANG • 47 So 4/2014 Tgp chi Khoa hoc - Cong nghe Thuy s n = 0.3; Lfng suit chdy s^ = 297 MPa [7] Mgt eal ngang duac phan chia Ihdnh 15 phln td danh s6 tii d i n 15, vdi vi tri vd thdng so kich thude cua cdc phan tir nhu bang Bdng Bang thdng so cdc phan tu> ciia mgt cat ngang Hinh thi hidn mat eat ngang giua tdu 2000 DWT vdi cdc thing so kieh thudc dupe cho true tiep frdn hinh ve Thdng so vgt lidu nhu sau: Md dun dan hoi E = 207000 MPa, He s i Poisson Phan tir IhO 10 11 12 13 14 15 Tam 1600-xl 1600*x1 1600*x1 1343.6-xl 1338*x, 1475*x, 1600*x, 1100*10 1900M0 1600-8 1600-8 1600-x, 1600*x, 1450-x, 1100'x, Vj bi gSc ph^n tiiPhuwigz Phirong y Kich thuiK cua phan tir N,p gia cu^g FB (x,-x,-x,)/,*x3 FB {x^-x,-x,)/,*x4 FB (x^-x,-x,)/,'x4 FB (x^-x,-x,}/2*x FB (900-x,)/2 x2 T X, V X X Tx,-xAX FB 850-x, 1400*10/100*10 1400*8/100*10 1400*8/100*10 FB {x^-x,-x,)/2*x FB (x.-x,-x,)/2*x FB (x,-x,-x,)/2*x FB (x^-x,-x,)/2*x Trong mo hinh tren, xem nhu kit clu boong khdng doi, cae tham so eua bai toan t i i uu ehi bao gIm cdc k i t cau tdn vd ngoai vd trong, song ehinh, sdng phy vd xd dpc mgn 2.3 Lidn kit biSn thiit ke Cd t i t cd bien thiet ke d md hinh tinh nhu tren dupe ddt ten tu x, d i n Xg nhu sau x,: ehilu day tdn vd ngodi, x^: chilu ddy ton v6 trong, x^ ehilu ddy sing chinh, x^; chilu ddy song phu, x^: ehilu cao sing chinh vd song phy, x^: chilu ddy bdn bung xd dpc mgn, x,: chilu cao ban byng xd dpc mgn, x^' ehilu ddy ban cdnh xd dpc mgn, x9: ehilu eao ban ednh xd dpc man Vdi s i lupng biln bai todn trd nen cong kenh va thdi gian tinh todn Idu, dd can thilt phai lien k l l eac biln thilt ke Igi d l giam so lupng bien [1, 9] Ket qua lien k i t biln thilt ke nhu sau: - X, Id biln ehleu day Ion v6, bao gIm hai bien X, vd Xj Gia trj ma bien X, nhdn duac Id to hpp cua hai biln (vi dy X, = [10 8] Id tdn vd ngoai cd gid tri 10 mm vd t i n vd co gid tri mm - X^ Id biln song dpc ddy, bao gom ba biln X3, x^ va Xg Gid tn md bien X^ nhdn dupe la to hpp ciia 0 1600 3200 4500 5400 5400 5400 5400 3200 1600 Ghi chll Do! xij'ng 0 750 2200 3700 5400 5426.5 5429.8 5431.7 750 1600 3200 4500 750 G6c Doi Xi>ng D6i Xijiig 750 750 ba bien eon (vi dy X^ = [12 10 750] la chieu ddy song ehinh, song phy vd chieu cao c6 gia tri tuang dng 12,10 vd 750 mm Tuy nhidn d l dam bdo t h i ticti khoang hang thi eo djnh gid tn biln x^, nhu vdy thuc chat biln X^ ehi bao gIm hai biln eon Id x^ vd x^ - Xj Id bien xd dpc mgn, bao gom bon bien Xg, x^, Xg vd Xg Gid tri ma bien X3 nhgn dupe Id A hpp eiia bin biln (vi dy X^ = [10 100 250] la ehieu day, chieu cao ban byng xd dpc man vd chieu day chieu eao ban cdnh xd doc man cd gid trj tuong ung 10,100, vd 250 mm Trdn ca sd khao sat ede thong so eiia thep ddng tdu, xdy dung eac bang t i l l dign luang ung vdi cac biln thiet ke da lidn k i t [7] 2.4 Xay dung h4im mi,tc tidu Ham muc tieu nghien cuu la trpng lupng eiia k i t c l u , nhien theo chilu ddi tdu, mat oil ngang k i t cau hlu nhu khdng thay doi (Chi thay doi d phan mui vd phdn dudi tdu) va xem rang vdt lieu ddng tdu cd trpng lupng rigng nhu nen ham myc tidu trpng lupng k i t eau eo t h i chuyin thdnh dign tich eua mgt eat ngang khu vyc giua tdu Nhi/ vgy ham myc tidu dupe xdc djnh Id: Z = 20913,3.x,+(10800-2.Xi).x-,+ X3.X5 + 4.X4.A5 + 4.X6.A, + 4.X^.Kg (2') D l thugn tien eho bdi todn toi uu ta se vilt lai theo ede biln lidn kit: SA-3 do: S^, = 0913,3.X| + (10800 - x,).X2; S^, = X3.X5 + 4.X4.X5; S ^ = 4.X6.X, + x „ x 48 • TRL/ONG OAI HOC NHA TRANG {2) So 4/2014 Tgp chi Khoa hoc - Cong nghe Thuy sdn 2.5 Xay dung ham r^ng budc Hdm rang bude bdi todn t i i uu hda k i t eau Id rdng budc v l dd bin, dp eung, ehuyen vj on djnh Tuy nhien theo phuang phdp Smith, ehii y l u tdp trung vdo bai loan mat on djnh mien deo va da ddm bao rang bupc ve on djnh thi ede rang bupc ve dp ben, dp eung se thda man [14] Khi md men u l n doc tdu tdc dung vao mat eat ngang tang dan thi gdc xoay giua hai mat cat ngang va ung suat tren tung phan tu k i t cau cung se tang len Vdi gid trj gida hai mat cat ngang Idn nhdl ma tat ea eac phan tu van dam bao dieu kien on dinh se xdc dinh dugc gia trj tdi han md tuang dng vdi no la mo men Idn nhat ma mat cat ngang chju duac Nhu vdy ung vdi mpt mat cdt ngang cu the thi se xae djnh dupe mpl gia trj mo men uon Idn nhit mat cdt ngang dd cd t h i chju duac theo dilu kien on ^ n h Do dieu kien rang bude dupc xdc djnh theo d n g thuc: (3) Trong M ^ vd Mg^ la mo men uon Idn nhdt ma mat eat ngang chju duac tdu nam a dinh sdng (Hogging condition) va ddy song (Sagging condition), cdc gid tri [iW„„^ va [M^^ la gia tn md men uon eho phep hai frudng hpp tau nam d dinh sdng va day sdng dupe tinh theo quy phgm eua to chdc ddng kilm lACS [10] Xdy dijvg thu$t toan Bai toan t i i uu hoa kit clu tau vd thdp thupc ldp bdi toan toi uu hda phi tuyen eo rdng bu|c, cac hdm rdng buOc khong t h i xae djnh dudi dang eac ham ludng minh Nhu da phdn tich d tren, d l tim nghiem t i i uu loan eye eo t h i su dung eac phuang phap thupc nhom dya tren nen tang tiln hda Nhdm phuang phdp xuat phdt tu mdt quan t h i ban dau vdi hu-u han so cd t h i ma mli cd the Id mpt nghidm cua bai loan toi uu Sau cdc bai todn ti> ddt biln, lai ghep, ehpn loc, tdi sinh se lim dupc mpt quan the mdi eo eac ea the (la ede nghiem) ed gia tn hdm muc tieu bang hogc t i t han (eu t h i bdi loan la nhd han) Mil quan the mdi ndy dupc gpi Id mOt t h i hg va nghiem loi uu todn cue se dupc xac djnh sau mpt s i hifu hgn the he Tuy nhidn de dgt dupe nghiem thi so lan lap rat Idn va thuc t l thudng chap nhgn sal so so vdi nghiem toi uu loan cue d l gidm khli lupng tinh todn Gidi thuat ndy phu hpp eho vide tim kiem nghigm sa bp, thu gon khdng gian tim kiem de Idm dau vao eho ede phuang phdp khde han Id ty than no tim nghiem t l i u u [ 15] Vdi thugt toan tim kiem tryc tilp, chae chan cho nghiem toi uu loan cue va nhupc dilm khoi luang tinh todn Idn se duac khac phuc bang each kit hpp vdi phuang phdp mat cdt vdng la phuang phdp dp dyng cho trudng hpp tim nghiem t i l uu ciia eiia hdm mpt biln Npi dung Ihuat todn kit hpp Irinh bay d hinh oan [AZ] mnh Str thu3t todn k^t hop TRUONG OAI HOC NHA TRANG • 49 So 4/2014- Tgp chi Khoa hgc - Cong nghe Thuy sdn Trong thudt todn k i t hpp, bude kilm tra nghigm Id bude phdn tich k i t eau theo phuang phap Smith, d budc n l u thia man dieu kl§n rdng bupc thi phuang an dua vao kilm tra Id mOt nghigm Khi gan [X] = [X\^^^ n l u phuang an la nghigm cd nghTa Id vdi cac l i l t didn bd nhit bdng tilt dign k i t c l u v i n dam bdo dp ben Nhu vgy e l t h i k i t ludn day la nghidm t i l uu ctia bdi todn Dieu ndy xdy xdy dyng bang tilt dign da sd dung cdc t i l l dien Idn hen yeu eau eua k i t cau, do c l n xdy dyng Igi bdng tilt didn vdi cdc tiet dign nhd han vd quay Igi bdi toan toi uu Khi gan [X\ = [X]^^ neu phuang an khong phdl la mpt nghidm cd nghTa Id vdi ede tilt dign Idn nhit k i t c l u cung khdng dam bdo ben Lue ein xay dyng Igi bdng tilt dign vdi eac tiet dign Idn han vd quay Igi bai todn t i l uu Trong trudng hpp [X] = [JSn„,„vd nghigm vd [X] = IX\^, cd nghi$m, tiln hdnh'"tfnh gid trj Z^^ theo phuang phdp mdt eat vdng va tim nghigm trdn cdc phuang dn c6 gid trj ham myc tieu Z = Z ^ Nlu tim thiy nghiem se gdn Z^^ Z^^ vd ngupc Igi gan Z^= Z^^ va quay Igi tinh Z^,, theo phuang phdp mat e l l vdng Dilu kien ddng eiia vdng Idp Id AZ - ZJJ-ZL< [AZ], tdc la khoang each gid trj can trdn va edn dudi gia trj hdm myc tieu x l p xi Sai s6 cho phdp AZ cang nhd tht ket qua t i l uu cdng chfnh xdc, Bude dd lim nghigm la mpt thudt toan con, qud trinh d l tim, vdi mSi phuang dn sd dupc kilm tra nghidm d l xae djnh phuang dn cd phai la nghidm hay khong Thudt todn tim nghigm trinh bay d hinh Hinh Stf thu&t loan d5 Dm nghidm thay nghigm se tang biln X, len 91a trj ke tiep Bat dau tim tu X, = X,^^^ va Xj= X^^,^, gid bang t i l l dign X, Chuang trinh dung Igi tim thiy tn biln X3 dupe tinh tu cong thirc d l ddm bdo nghiem (ed nghidm) hogc ca X, va X^ dat gia tri phuang an dang xdt la phuang dn lam cho Z=Z.g Idn nhat md vdn khing tim thay nghiem (v6 nghidm) Tuy nhien gid tn X3 Eheo tinh toan Id mpt gia tri bien khdng ndm bang tilt dien da xdy dung, can III K^T QUA NGHIEN CLTU VA T H A O L U A N phdi hidu chinh bien X3 bdng mot gid tri g i n nd nhit Thugt loan tim kilm true tilp, phuang phdp kit cd bang tilt didn hpp vd phuang phdp tiln hda dupc ldp trinh bdng Sau mli phuang an thay doi eac bien thiet ke ngdn ngd Matlab, ca ba chuang trinh ndy eung can phdl kilm tra dieu kign nghiem Neu phuang dupc su dyng d l tinh nghiem t i l uu trdn eiing mot an dang xet khong phai Id nghiem thi tang gid tn bp thdng s6 d i u vdo (cdc bang tilt dign) Xj len gia tri ke tilp bang tilt didn X^ Trong trudng hap X^ tang d i n X^>Xj^^^ ma van chua tim Kit qud tinh toan t i i uu trinh bay bdng Bang Bang so sdnh ket qua t i i uu T.ng„ (mm) X,/X, x^x Xs xA x./Xo S (mm^) N (lan) Chieu d^y t6n v6 ngo^i/ Chieu day ton song chinh/phu Chieu cao song chinh, song phu Chieu day/chieu cao ban byng xa dpc man Chieu day/chieu cao ban canh xa dpc man Dien tich mat cit ngang (phan toi i^u) So lĐn phan tich kĐt cau 50 ã TRt;ONG DAI HOC NHA TRANG Theo th\rc TheoTTTK te che 190 tivctiep 10/10 12/10 750 8/250 10/100 367933 TSi uu theo Keth?p KithTp thu|lt todn ahutmg phdp phuvng phap tienhOa chia dfil m^tcitvanq 9/9 9/9 9/9 16/13 16/13 16/13 750 750 750 8/200 8/200 8/200 10/150 10/150 10/150 348657,7 348667.7 348657,7 4526 121500 3851 9/9 16/15 750 8/300 8/100 350057,7 5801 Tgp chi Khoa hgc - Cong nghe Thity sdn Do phuang phdp tiln hoa cd tfnh nglu nhien, mli lan tinh toan toi uu cd t i c dO hpi ty khde nen nghien cdu da tinh todn nhieu lan de tinh ket qua trung binh Mgt khac nlu yeu c l u tim nghidm t l i uu todn cue, diuang trinh se tinh r l l lau dd nghidn cuu chap nh|n sai so 2% d l gidm thdi gian tinh todn Theo thugt todn tim kiem tn^c lilp dd xdc djnh nghigm toi uu va luang ung vdi nghigm Id gid tri hdm myc lieu (dign tich mgt cdt ngang) Z = 348657,7mm^ So sdnh vdi tau thyc t l da c h i tao (Z = 367933mm^) thi k i t c l u sau toi uu da giam 5,24 % didn tieh mgt cdt ngang Vdi phuang phdp k i t hpp thugt todn tim kiem tryc tilp vdi thugt todn chia doi da xac dinh nghidm toi uu toan cyc hodn todn chinh xdc nhung da gidm so i l n phdn tich ket cau tu 121500 lan xuing 4562 lan, luang ung gidm 96.3% Vdi phuang phap k i t hpp mgt eat vdng thudt todn tim kiem tryc tilp vdi phuang phdp mat cdt vdng, da xdc djnh nghigm toi uu todn cue hoan todn ehinh xdc nhung da giam so Iln phdn tich kit clu td 121500 lan xuIng 3851 i l n , tuang dng gidm 96.8% Vdi phuang phdp lien hoa, xac djnh nghigm ung vdi gia In hdm myc tieu Z=350057,7 mm^ Id So 4/2014 nghiem t i t nhat qud trinh linh, ddy ehua phai Id nghigm toi uu Tuy nhien n l u lya chpn phuang an ndy cung se giam dign tich mgt cdt ngang dupc 4% So lan phdn tich kit eau so vdi thugl todn tim kilm tn/e tilp giam tir 121500 xuong 5810 lan tuang irng gidm 95% Tuy nhien so vdi phuang phdp ket hpp mat cat vdng, so Idn phdn lich ket cau van Idn han 1950 lan, tuang ung Idn han 33,6% Mgt khde, phuang phdp t l i uu tien hda ed thdi gian tinh loan trung binh gap ba Idn fridi gian tinh theo phuang phdp k i t hap Sd dT Ihdi gian tinh todn kdo ddi khdng ty Id vdi so lan phan tich k i t cau la ed nhieu budc (ma hoa, dpi biln, giai ma, lai ghep ehpn Ipc) xen ke ede lan phan tich ket eau lam cho khoi lupng tinh toan tang len dang k l IV K^T LUAN Kit hap Ihugt todn lim kilm true tilp vdi phuang phap mat cat vdng cho phep tim dupe nghiem t l i uu todn eye vdi so iln tinh nho nhat eac phuang phdp da so sdnh Tilp tyc nghidn cdu thugt loan tiln hda theo hudng sd dung phuang phap Id nghiem ban dau cho cdc phuang phap khac TAI LIEU THAM KHAO 10 11 12 13 14 15 TiSng Vi^ V6 Nhu ciu 2003 Tinh kSt c5u theo phirong phap t6i iru NXB Xay dipig Dang kiim Vigl Nam, 1997 Quy pham phan cSp va dong tau biSn v6 thep TCVN 6952 : 1997 Ha Npi IA Xuan Huynh, 2005 Tinh toan k^t c^u theo ly thuyei toi uu NXB Khoa hoc va ky thuat Phgm Ba Linh, 2014, Nghien ciru toi uu hoa ket cau t^u v6 thep sir dung ket bpp thuat toan chia doi va dm kiSm imc tiep Tap chi Khoa hgc - cong ngh? Thuy san So ! PhamHfingLuan, D.T.N., 2010 NghiencihiiingdunglhuattoanACO(Antcolony optimization) toi uu thai gian va clii phi xay dung Tap chi phat trien KH&CN, T?p 13, Ql Trin Minh, Nguyin Quan Thang, Hoang Manh Khang, 2012 Giai bai toan loi ini hoa ket cau duoi may bay tnrc thang bang thuat toan tien hoa HQC V I ^ Ky thuat quan sir So 148 Nha may dong tau Nha Trang, 2001 H6 sa thifit kl ky thuat tau hang 2000DWT Nguyen Dinh Thuc, 2009 Tri tu? nhan tao - lap trinh tien hoa NXB Giao Due Nguyen \^ilt Trung, 2003 Thiai kfi tdi mi NXB Xay dung Tieng Anh International Association of Classification Societies lACS 2010 Caldwell J B., 1965 Ultimate Longitudinal Strength Transaction of RINA, 107: 411-430 Cho, S.R., Choi, B.W„ and Frieze, P.A, 1998 Ultimate strength formulation for ship's grillages under combined loadmgs Proceeding of the 7th International Symposium on Practical Design of Ships and Mobile Units PRADS'98, Hague, 125-132 International Ship and Offshore Stuctures Congress ISSC Report of special task committee VI.2 (Ultimate hull girder strength) 2000 Nagasaki, Japan Smith, C.S 1977 Influence of local compressive failure on ultimate longitudinal strength of ship's hull Proceeding of the Intemaiional Symposium on Practical Design in Shipbuildmg Un Kirsch, Optimum structural design New Yoric, US A McGraw - Hill Book Company TRUONG DA! 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