Mo hinh hoa qua trinh khoan tao lo coc
• • •
khoan nhoi (chiFa xet den rui ro)
Ngay nhan bai: 6/12/2013 Ngay siia bai: 13/12/2013 Ngay chap nhan dang: 28/12/2013
Nguyen Quoc Bao, Pham Hoang
TOJVl T A T :
Tren co sd cac dac triing so va luat phan phoi cua cac cong doan chu yeu trong qua trinh thi cong khoan tao 16 cpc Ichoan nh6i, tac gia da tien hanh mo hinh hoa qua trinh thi cong nham dp bao tien dp cia qua trinh Idioan tao 16.
ABSTRACT
Based on the numerical characteristics and the law of distribution of the main steps in the drilling bored piles construction process, the author carries out simulating the construction process in order to forecast the progress of the drilling bored piles construction process.
PGS.TS Nguyen Quoc Bao Th.S Pham Hoang
Master of Civil Engineering and Industry The IVIilitary Technical Academy Di dgng: 0912.129.276
Email: [email protected]
1 . €>at van de
Be tien tdi danh gia dp tin cay ciia qua trinh thi cdng cpc khoan nhdi ed xet den cac yeu td ngau nhien va riii ro thi viec md hinh hda qua trinh thi cdng khoan tao 16 la het sUc c i n thiet.
Bai bao trinh bay cae bude md phdng qua trtnh khoan tao 16 epe khoan nhdi theo phuong phap Monte-Carlo.
2. PhUtfng phap mo phdng IVlonte - Carlo Md phdng sd Monte - Carlo cd cd sd toan hpc la phUdng phap Monte - Carlo, mdt edng cu toan hpc manh de md hinh hda cac he thdng phUe tap, trong dd cd sU tham gia ciia cac yeu td ngau nhien. PhUdng phap nay ra ddi vao khoang nhCfng nam40ciia theky hai mUdi.Ten tuoi ciia phuong phap ehinh la mat danh eiia nhUng dp an mat trong ITnh vUc ky thuat hat nhan, trong dd, lan dau tien phUdng phap ra ddi va dupc Ung dung. Vao nhUng nam tiep theo, do tinh manh me ciia phuang phap, phuong phap Monte - Cario l i n lupt dupe ap dung vao eac ITnh vue khac nhau cua khoa hpc ky thuat.
Tuy nhien Idi giai cac bai toan phUc tap theo phuang phap nay tren may tinh doi hdi nhieu ve thdi gian eung nhu bd nhd ciia may. Vi vay chi tdi nhdng nam g i n day, khi cdng nghe may tinh da dat tdi hoan thien ve mpi mat, phUdng phap Monte - Carlo mdi thuc sp dupe sd dung rdng rai.
Khi c i n giSi cac bai toan cd dac tinh ngau nhien, c h i n g han bai toan xac djnh cae dac trUng xac suit cua ham ddi sd ngau nhien, bai toan truyen cae qua trtnh ngau nhien qua eac he thdng ddng hpc, cac bai toan theo md hinh ciia ly thuyet phuc vu dam ddng... Cac ldi giai giSi tich thudng chi eho ket quS trong nhdng trudng hpp het sUc don g i i n ve dac trUng phan bd ciia cac bien ngau nhien dau vao, don g i i n ve dang ham va cac he thdng dpng hpc.
Tuy nhien thUc te ddi hdi giai cac bai toan tren trong cac dieu kien phdc tap hon, phSn anh khach quan hfln cae dien bien thuc, tham chi
khdng the md tS tudng minh cae dai lupng ra can tim theo cac dai luong vao. De giSi cac bai toan phUc tap thudc idp nay, cd the ndi cho tdi nay duy nhat chi ed phUdng phap Monte - Carlo la thUe su hieu quS va md phdng tren cd sd phuong phap nay da t r d thanh mdt trong nhUng cdng cu manh n h i t de giai eae bai toan thudc ITnh vUe phan tich he thdng va Ung dung.
Ndi dung cd bSn ciia phUdng phap tdm lupc qua bdn budc sau:
. Budc 1: Md hinh hda cac bien n g i u nhien d i u vao, cac bien ngau nhien tham gia vao he thdng. ThUc c h i t ciia qua trtnh md hinh hda la b i n g each nao dd cd the tao ra cae the nghiem eiia eae bien ngau nhien, qua trinh ngau nhien ed dac trUng xac suit mong mudn.
. Budc 2: Md hinh hda toan bd eac dien bien trong he thdng tU dau den cudi qua trinh, sao cho ta cd the nhan dupe cac the nghiem ciia cac dai lupng ra c i n tim tUOng Ung vdi cae the nghiem d i u vao va tham sd he thdng. Bang budc nay cd the coi la ta da thiet lap dupe mpt md hinh thir nghiem bat chudc he thdng thuc.
Diem e i n n h i n manh d day la thay vi phai thiet lap cac quan he toan hpc phUc tap gida dau vao va d i u ra ciia he thong, ta xay dung lupc do thi nghiem cua he thdng.
• Budc 3: Xay dpng cac chien lupc va chien thuat thU nghiem tren md hinh. Moi md hinh gan lien vdi mdt he thong thUe.Tuy nhien tren md hinh lai cd the thUe hien nhieu t h i nghiem khae nhau gan lien vdi nhieu muc dich nghien cdu khac nhau. Lap lai eac chien lupc va chien thuat thU nghiem tren md hinh mdt so hOu han l i n ta dupe tap cae ket quS d i u ra.
. Budc 4: Xd ly thdng ke tap ket quS d i u ra tren ta dupc cac ket qua mong mudn.
3. Md hinh hda thi cong khoan tao 16 3.1. Muc tliu chuang trinh
TU trudc tdi nay khi ndi den tien dp thi cdng khoan tao 16 epe khoan nhoi ndi rieng va cac edng tac trong xay dpng ndi chung deu dua
oi.2oi4nDniPBX 113
tren tieu chuin va kinh nghiem, eae mdc thdi gian dua vao deu da dupc tien djnh hda. Ddng thdi tien dp thi cdng dupe xay dung theo each lam nay chua xet den nhdng rui ro cd the gap phSi trong qua trtnh thi cdng, nhdng rui ro nay cd the dan den keo dai thdi gian thi cdng, lam tang chi phi va ed the Snh hudng tdi chit lupng ciia sSn pham. Vl vay bang tien dp thi cdng cdn d mdc ddn giSn, chua phSn anh sat thuc te khach quan.
Tren thUe te, qua trinh thi edng dien ra ngoai edng trudng, chju nhieu yeu td tac dpng ciia thdi tiet, cac yeu td ngau nhien tac ddng den qua trtnh thi edng la rit ldn nhu yeu td ngau nhien ve tSi trpng, vat lieu, kich thudc hinh hpc... va dae biet la qua trtnh thi cdng chju Snh hudng Idn bdi yeu td con ngudi, ehinh yeu td nay lam qua trtnh thi cdng khdng cdn hoan toan khach quan.
Qua trtnh thi edng chju tac dpng bdi rit nhieu yeu td rui ro, nhieu eac tac dpng ngau nhien nen yeu eau dp bao ket quS trong thi cdng la het sufc cap thiet. Vi vay cin hudng tdi hinh thanh bai toSn thi cdng nhu bai toan dp tin cay. Trong thi cdng chap nhan yeu td ngiu nhien ciia cac cdng doan thanh phan nhu la mpt tat y^u. Chat lupng cua bi§n phap thi edng la mpt ham da muc tieu gdm ky thuat thi cdng, tien dp thi edng, tinh hpp ly ve kinh te, an toan lao ddng va ve sinh mdi trudng. BSn chat ciia bai toan nay thupc ve khdi dieu khiln hpc, ed sp tham gia cCia con ngUdi, nd chju Snh hudng bdi quyet djnh cua con ngUdi nen khdng the md tS hoan toan bing cae thii tuc toan hpc dupc. Bai
bao tap trung vao dU bao tien dp thi cdng dudi gdc dp dp tin cay, eac tidu chi chat lupng khac dupc lay theo tieu chuan.
Muc tieu ciia chuong trinh md phdng qua trtnh thi cdng khoan tao 16 cpc khoan nhdi nham md tS mdt each sat thUe qua trinh thi cdng ngoai cdng trudng, giup cho ngUdi chi huy lUa chpn bien phap thi cdng mdt each tudng minh va cd cd sd khoa hpc. Gidi han cda chuang trtnh la md hinh hda tien dp thi cdng khoan tao 16.
Cac sd lieu dupc thu thap de phuc vu cho qua trtnh md phdng chi dung vdi may khoan KH180 va khoan cpc vdi dudng kinh 800mm.
3.2. Thong so tfau vao 3.2.1. Thiet bi, nhdn iUc
Thiet bj dupc sU dung trong qua trtnh khoan tao 16:01 maycaukyhieuKHISO.OI may dao giu nghjch hieu HITACHI dung de ciu dat len xe chd ra khdi cdng trudng, 01 may bdm hut sau sir dung de xir ly can ling hat mjn.
Nhan lUc gdm: 01 lai may khoan, 01 lai may eau, 04 edng nhan phuc vu khoan, 01 cdng nhan true bentonltte, 01 ky sU trie dja.
3.2.2. Bdng so lieu dau vdo
De ket quS md hinh hda dupe tin cay, can day edng theo ddi ghi chep va xU ly thdng ke cae cdng doan thanh phin. Dudi day dan ra cac ket qua xU ly thdng ke cin thiet, dii cho qua trtnh md phdng. Mdt sd trong cSc ket quS xd ly thdng ke d day da dupe trinh bay trong bai bao
"Xd ly thdng ke cae cdng doan thi cdng chii yeu ciia qua trtnh thi cdng khoan tao 16 cpc khoan nhdi"-Tap ehi xay dung 12/2013. Cac ket quS nay chi dung eho may khoan KHI 80.
Dieu kien dja chit tai vj tri thi cdng cpc khoan nhdi dupe cho trong bSng sau:
sn
1 2 3 4 TK1
5 TK2
6 TK3
7 8 9 10
Loai tf^t eat lap Setphad^ocijfng Set pha deo m^m Cat hat trunq nho chat vira Set pha deo cUng Set pha iiu chJy Cat hat tmng chat vira Set pha d§o cijfng Set pha deo m j m Cat pha chat vira Set pha deo mem Catnhi
Cuoi s6i lan cat hat trung , chat vira
Chilu day (m) 1,5 4,5 9,9 10 1,4 3 3 3,6 2,0 1,1 4,0 3,6 Cgc khoan vao
ldpnay1,5.D
Ngoai may khoan KHI80, dieu kien dja chit la sd lieu diu vao co bSn. Chuong trtnh cho phep du bao tien dp khoan cua may khoan KHI80 qua cac ldp dja chat cho trong bSng tren. Khi khoan qua cac Idp dja chit khdng c6 trong bang tren phii do dac va xir ly thdng ke bdsung.
3.2.3. Phdn chia quy trinh thi cdng khoan tqo id cgc khoan nhoi thdnh cdc cdng doqn
Viec phan chia cdng doan va bd tri may thi cdng cung nhu lao ddng dupc trtnh bay trong bSng sau:
STT 1 2 3 4 5 6 7 8 9 10 11 12 13 14
15 16 17 18 19 20 21 22 23 24
Ten cong doan Lap gau khoan D1000 mm.
Chinh tim giu khoan trung vol tim coc.
Tha'ogju khoan D1000 mm.
Chen dat quanh Casing.
Lap g3u khoan D800 mm.
Thai gian xoay gau d§n dinh h i khoan Thai gian khoan trong 3k lap Thai gian khoan trong Jat set pha deo ciing Thai gian khoan trong d i t set pha deo mim Thai gian khoan trong 6k set pha deo chay Thai gian khoan trong dk cat hat trung, hat nho chat vua Thai gian khoan trong dk cat nho
Thai gian khoan trong dat cat pha chat vija Thai gian khoan trong l a t sol cuoi
Thai gian xoay gau den vi tri d6 dat Thai gian d i d a t lap Thai gian d9 dat set pha deo cijing Thai gian do d i t set pha deo chay Thai gian d i d i t set pha deo mim Thoi gian d i d i t cat hat trung, hat nho chat viia Thai qiandi d i t cat nho
Thai gian d i d i t cat pha chat viia Thai qiandi d i t cuoi s<)i Thai gian do chieu sau ho khoan
Plian plioi Phan phoi chuan Phan phoi chuin Phan phoi chuan
Phan phii chuan Phan phoi chuan Phan phii chuin Phan phoi chuin Phan phiichuin Phan phoi chuin Phan phii chuin Phan phii chuin Phan phoi chuin Phan phii chuin
Phan phii chuin Phan phoi chuan Phan phoi chuan Phan phii chuin Phan phii chuin Phan phii chuin Phan phii chuin Phan phii chuin Phan phii chuin Phan phii chuin
Ky vpng (giay) 60 61,8
59 204 60 8,83 56,63 18,38 17,80 14,2 37,9 31,2 42,6 164,56
8,25 9,36 12,11 12,6 22,96 12,6 16,8 11,4 16,77 120
Do lech chuan 6 15,5
3 6 0,55 19,87 4,49 3,51 2,1 7,9 6,6 5,85 27,96
0,8 1,88 3,69 2,4 6,97 3,8 1,5 1,5 1,79 14
He s6 bien sai Ghi chu
0,1 1
0,25 0,05
0,1 0,06 0,35 0,24 0,2 0,15 0,14 0,21 0,14 0,17
0,1 0,2 0,3 0,19 0,3 0,3 0,09 0,13
1 M^
0,12
Tiin dinh hoa
1 1
l4B(»ni:iBin 01.2014
sn
1 2 3 4 5 6__j 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27
Ten cong doan D.on dep mat binq h i khoan Binh vi tim coc Gthmic
Lip giu khoan D1000 mm Chinh tim gau khoan trung vol tim <:oc Khoan lln 1 (din day Casing) Thao gau khoan D1000 mm Ha ing Casing Nghiem thu Casing lan 1 Chen dat quanh Casing
ciu thep hinh do ing Casing (dat canh ho khoan) Chinh Casing lin 1
Nghjem thu Casing lan 2 Chinh Casing lan 2 (neu can) Nghiem thu Casing lin 3 (niu cin) Chinh Casing lin 3 (nlu can) Nghjem thu Casing lin 4 (nlu cin) Lip giu khoan D800 mm Khoan lln 2 (din lop cuoi sol) eo chiiu sau hi khoan Khoan lin 3 (khoan b i sung 1,5D) eo chiiu sau h i khoan Cho vet ling hat tho (30 phiit) Lip giu vet chuyen dung Vet can lang hat tho Thaogau
eo chieu sau ho khoan sau vet ling
May thi cong May dao
Maykhoan May khoan May khoan May khoan May khoan
Nhan cong 01 lai may OIKS trac dia, 02 CN
02 CN 01 lai may, 01 CN 01 lai may, 02 CN 01 lai may, 01 CN 01 lai may, 01 CN 01 lai may, 02 CN 1 OIKS trie dia, 02 CN May dao
May khoan May khoan
May khoan
May khoan
May khoan May khoan
May khoan
01 lai may 01 lai may, 02 CN 01 lai may, 02 CN OIKS trac dia, 02 CN 01 lai may, 02 CN OIKS trac dia, 02 CN 01 lai may, 02 CN OIKS trac dia, 02 CN 01 lai may, 01 CN 01 lai may, 01 CN
02 CN 01 lai may, OKN 1 02 CN
May khoan May khoan May khoan
01 lai may, 01 CN 01 lai may, 01 CN 01 lai may, OKN
02 CN
3.3. Sd do thuat toSn Md phdng theo trtnh tU thi edng
Trong trinh tp tren ta cd 3 chu trtnh khoan, cac chu trtnh khoan hoat ddng theo thuat toan sau:
PhSt: -I-Thdi gian xoay gau den vjtn khoan -I-Thdi gian ha g i u den day hd khoan -HThdi gian khoan den khi diy giu -f Thdi gian keo gau len dinh ho khoan -I- Thdi gian xoay gau den vj tri do dat +Thdi gian dd dat
Phat: Ah
Lap gau khoan D1000 mm
Chinh tim g i u khoan triing tim cpc
Khoan lin 1 (den day Casing )
Thao giu khoan D1000 mm
Ha, can ehinh, nghidm thu Casing
Chen dat xung quanh Casing
Lap g i u khoan D800 mm
Khoan lin 2 (den Idp cudi, sdi)
Do chieu sau hd khoan
Khoan l i n 3 (khoan bo sung 1,SD)
Do chieu sau hd khoan
Chd30phiit,thaogauD800mm,lipgiuvetling
Vet can ling hat thd
Nghiem thu ho khoan
Thao gau v^t lang
Tinh the tich Bentonite va tdc dp cap Bentonite
h = h + ah
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3.4. Thong sd dau ra
Thdng sd d i u ra la nhdm thdng sd ve c h i t lupng bao gdm thdi gian thi cdng cac cdng doan, the tich bentonltte c i n sU dung trong moi cdng doan, tdc dp c i p bentonltte trong moi cdng doan, dp sau khoan dupc sau moi cdng doan thi cdng, dp sau tong cdng da khoan dupc sau moi cdng doan, tdng thdi gian thi cdng.
Ket quS md phdng dupc trinh bay dudi day:
Cong doan 1 2 3 4 5 6 7 8 9 10
Thai gian cdng doan(phut)
1.0000 1.0300 0 . 9 6 1 5 1.2218 1.4491 0 . 6 7 5 1 0.9584 0 . 8 6 1 1 1 . 1 2 3 1 0 . 9 2 4 3
The tich bentonitte(m')
0 . 0 0 0 0 0 . 0 0 0 0 0 . 4 5 9 8 0 . 5 0 3 3 0 . 4 7 6 4 0 . 4 9 0 3 0.4382 0 . 4 7 2 5 0 . 4 4 4 7 0.4 62 9
Toe dp cap bentonltte (m^
0 . 0 0 0 0 0 . 0 0 0 0 0 . 4 7 8 2 0 . 4 1 1 9 0 . 3 2 8 8 0 . 7 2 6 2 0 . 4 5 7 3 0 . 5 4 8 7 0 . 3 9 5 9 0 . 5 0 0 8
Ddsau khoan duoc 0 . 0 0 0 0 0 . 0 0 0 0 0 . 5 8 5 4 0 . 6 4 0 9 0 . 6 0 6 6 0 . 6 2 4 2 0 . 5 5 8 0 0 . 6 0 1 6 0 . 5 6 6 2 0 . 5 8 9 4
Dosauting
• ( m ) 0 . 0 0 0 0 0 . 0 0 0 0 0 . 5 8 54 1 . 2 2 6 3 1.8329 2 . 4 5 7 1 3 . 0 1 5 1 3 . 6 1 6 7 4 . 1 8 2 8 4 . 7 7 2 2
Tong thai gian thi cong (phut)
1.0000 2 . 0 3 0 0 2 . 9 9 1 5 4 . 2 1 3 4 5 . 6 6 2 5 6 . 3 3 7 6 7 . 2 9 6 0 8 . 1 5 7 1 9 . 2 8 0 2 1 0 . 2 0 4 5 90
91 92 93
3 0 . 0 0 0 0 4 . 8 0 0 0 1.9663 1.0001
0.0000 0.0000 0 . 0 0 0 0 0 . 0 0 0 0
0 . 0 0 0 0 0 . 0 0 0 0 o . o o o o 0 . 0 0 0 0
0 . 0 0 0 0 0.0000 0 . 0 0 0 0 0.0000
4 8 . 8 8 3 3 4 8 . 8 8 3 3 4 8 . 8 8 3 3 4 8 . 8 8 3 3
2 4 4 . 7 0 4 0 2 4 9 . 5 0 4 0 2 5 1 . 4 7 0 3 2 5 2 . 4 7 0 3 Hinh ve dudi day hien thi ket qua qua trinh mo phong. Cac ket qua nay dUOc hien thj tren cac bieu do trong hinh sau:
QUY TRINH KHOAN TAO LO 1. Lap gau khoan DIOOOmm 2. Chlnh tim gau tnjng tim ccx;
3. Khoan lan 1 (den day casing) 4.Thao gau khoan DIOOOmm 5. Ha, can chlnh, nghiem thu casing 6. Chen dat quanh Casing 7. Lap gau khoan DSOOmm 8. Khoan lan 2 (den lop cuoi soi) 9. Do chieu sau ho khoan 10. Khoan lan 3 (khoan t » sung 1.5D) 1 1 . Do chieu sau ho khoan
12. Cho 30 phut, Thao D800mm, lap gau vet lang 13 Vet can lang hat tho
14 Nghiem thu ho khoan 15. Thao gau w t lang
CHU TRWH KHOAN 1 Xsay gau den vi trt khoan 2 Ha gau den day ho khoan 3 Khoan den khi day gau 4 Keo gau len dinh ho khoan 5 Xoay gau den v tri do dat 6 Do dat
0 1 2 3
THOI GiMi CDfph) THE TICH BBg(m3) TOC DO BENCmVph)
:U
0 50 100 0 50 100 0 50 100 DOSAUCDCm) DOSAUTCm) j TMOI GIAN T(ph) 1 I 5 0 , ^ 4 0 0 ^ I
0 0-2 0 4 0 6 0.8 1 0 50 100 0 50 100 0 50 100
4. Ket luan:
- Qua qua trinh theo ddi thi cdng, tSc gia da tien hanh do dac va xd ly thdng ke cae edng doan eiia qua trinh lam thdng sd d i u vao cho md phdng qua trinh thi cdng khoan tao 16 cpc khoan nhdi.
K^t quS md phdng cho t h i y tong sd cdng doan, tong thdi gian thi edng, dp sau hd khoan kha phii hpp vdi thuc te. Nhu vay qua trinh chuan bj sd lieu va md phdng la dang tin cay.
- Chuong trtnh cd khS nang xay dung cac phan phdi d i n s u i t - phan phdi tong cua mdt sd cdng doan thanh phan lam co sd de md phdng cae he phdc tap hdn nhu md phdng thi cdng cpc ddn va thi cdng he cpc.
-TUcac so lieu tren ta cd the de dang tinh toan cac thdng sd c h i t lupng eua qua trinh thi cdng cpc n h u tong thdi gian khoan tao 16 trung binh, hieu s u i t sit dung phuong tien va nhan luc, ehi p h i . . . NhCfng v i n de nay se dupc hoan thien va trinh bay trong cac bai bao tiep theo.
TAILIIUTHAMKHAO
1. Ths Pham Hoang, PGS.TS Le Kieu, PGS.TS Nguyen Quoc B3o & Ths Nguyen ChiTho - "X(i ly thdng ke cac cong doan chi yeu cua qua trinh thi cong khoan tao 16 coc khoan nhoi'-Tap chi xaydimgs612/2013.
2. PGS.PTS. Nguyen Ba Ke' - Thi cong coc khoan nhoi - Nha xuat bin xay dung-1997.
3.TCVN9395:2012-Cgc khoan nhoi-Thi cong va nghiem thu.
4. Averill M.Law & W.David Kelton - 2nd ed. Simulation Modeling & Analysis.
