Ky niem 43 nam thanh lap Vien Khoa hoc Cong nghe Mo Vinacomin I/NGH!EN,CUU AP DUNG KET CAU KET HOP SUT DUNG NEO VA NEO CAP NHAM NANG CAO HIEU QUA CHONG GIUTCONG TRINH NGAM Active support structure wit[.]
Trang 1I/NGH!EN,CUU AP DUNG KET CAU KET HOP SUT DUNG NEO VA NEO CAP NHAM NANG CAO HIEU QUA CHONG GIUTCONG TRINH NGAM
Active support structure with using reinforced anchors and
cable anchors has many dominant advantages However,
during its application, it is necessary to have some control
methods for increasing its supporting efficiency and then, as a
result, for orientating the support design and selecting the
reasonable output and input parameters to increase the mutual
assistance between reinforced anchois end cable anchors The
paper refers to some methods in the coordinate uWization of
anchors and cable anchors for increasing the supporting
efficiency at underground constructions and mine dnfts
TS TRINH eANG HUNG
KS PHI VAN LONG
KS NGUYEN VAN CONG
KS HOANG PHUONG THAO
Vi$n Khoa hoc Cdng ngh$ Md - Vinacomin
Bien tip: TS Truxmg Dtrc Dif
LDatvdndl
Vgi nhung uu diem ca v l kha nang ching
giu, an todn, gid thdnh hp cung nhu phpm vi dp
dung, tLP Idu, k i t c l u chong Id bang vi neo da
dugc O-ng dung rpng rdi trong vipc ching giu
cac cdng trinh nglm, dudng Id md tren t h i gidi
vd g Vi^t Nam Trong qua trinh phdt triln, da cd
r i t nhilu k i t c l u neo dugc siJ' dgng trong thg'C
t l Theo cc ehe chju tai, ngudi ta chia ra neo ma
sdt, (neo nem che, neo Ing, ), neo dinh k i t
(neo be tdng cot thep (BTCT), chit deo c i t thep
(CDCT), neo cdp, )
Trudc day, nhung loai k i t eau neo nay
thudng dugc su dgng dpc lpp, tuy nhien, qua
thyc t l dp dgng cho thay, vipc su dgng mpt logi
neo ehua phdt huy dugc toi da nhung uu diem
cua k i t c l u chong neo Vi dg, khi ching giij" cdc
Id dpc via chiu anh hudng cua dp Ig'C Id chg,
hope cdc nga ba, ngd tu, khiu dp chong gii> Idn,
n l u chi' su dgng den thuin neo BTCT hope neo
CDCT, se khdng dam bao an todn Trong trudng
hgp ndy, n l u su dgng neo cdp se giai quylt
dugc bdi toan v l kha nang chong giu, tuy nhi^n,
gid thanh ching Id se tang
Hipn nay, a cdc nudc tidn t i l n trdn t h i gidi,
ngudi ta dd dua vdo dp dgng h0 k i t c l u ching
giu cdc edng trinh ngam cung nhu dudng Id md,
vdi vi$c k i t hgp neo vd nee cdp Ket c l u ndy
khdng nhQ'ng phdt huy dugc toi da uu diem cua
tung Iopi neo, dam bao kha nang ching giu on
djnh, an todn, md cdn giam gid thdnh ddo ching
Id
Bdi bdo ndu ra mOt s l phugng phdp k i t hgp
su dgng neo vd neo cdp nhim ndng cao hipu
qua chong giu cdng trinh ngam eung nhu cdc dudng Id trong cde md h i m Id
2 Nguyen ly k^t hp'p neo cdp vd neo cdt thep trong vipc chdng g i u cdng trinh n g l m Neo cot thep (BTCT, CDCT) va neo cdp d i u
la k i t c l u chong chu dpng, chju Ig'C theo cc c l u bam dinh Trong dd, neo cot thep cd chipc nang chu yeu Id lien k i t cac Icp da tao thdnh ban dam phia tren ndc Id, hgn che kha nang "freo" ching
da ndc tach khoi nguyen khoi Doi vci neo cdp, dgc diem cc ban la chilu dai len, chu'c nang
chinh Id "treo" da ndc len Icp vach cc ban Tu
do, trong h$ k i t cau ndy, neo cdp cd the tgo ra dugc dy ung Ig-c cao va nang Ig-c nhdn tai len, cdn hp thong neo cot thep xung quanh hinh
thdnh ban dam vd dugc neo cap "treo" len vdch
cc ban Nhu vdy, k i t c l u ndy sg hinh thdnh dam
t l hgp, bao vp da vach, han c h l djch dpng, ngan ngOa sy phdt trien cua vdm sgp Ic, khien cho lyc tdc dgng cua neo cdp vd neo cdt th6p lan can tucng hd cdng hucng, t l hgp hinh thanh len mpt dam da mdi, vci do day do cung, cucng
dp khdng cat cua d i m da nay tang len, ap luc ndc Id thong qua trg bao ve chuyin djch vdo sau bdn trong Thdng qua do, cai thien dilu ki0n chju lyc cua ducng Id, khing c h l hipu qua su djch chuyin cua dat da ndc va hdng Id
So sdnh vci neo cot thep, thi neo cdp ed dp sau gia co va lye gia co len, cd the tao dy ung lyc khd Idn vd hang logt nhung yu diem khdc,
ta mpt trpng nhung ky thugt quan trpng khdng
t h i thilu trong gia co cac cdng trinh nglm cd
d i l u kipn khd khdn phi>c tgp Neo cdp cd cdc logi khdc nhau, nhu neo cdp dy ung lyc d i u
Trang 2neo neo cdp dy yng lyc todn thdn, neo cdp phi
dy Cmg lye todn thdn neo cdp vdi hinh thCre
khde nhau thi co che gia co chdng giy cung khac
nhau Trong dd neo cdp dy ijng lyc dau neo
dugc sy dyng r^t pho bie'n Log! neo ndy chu
y l u Id tdc dgng treo Neo cdp mang Idp d i t dd
khdng on djnh Idp dydi treo vdo Idp d i t dd dn
djnh d phia tren Ddng thdi, do neo cdp cd t h i
tgo ra dy yng lyc khd Idn, ed t h i keo cang vd
dp chat cdc Idp dd, khe mit, nhijng mat khdng
lien tgc, Idm tang len lyc ma sal giOa cde mat
Idp, tip dd, nang cao cydng dd tong the khdi da
Neo edt thep vd neo cap khdng phai ch? don
gian Id tdc dgng ehdng giy k i t hop gia eydng
md con Id ehdng giy tyong hS i l y ddi b l trg
ngin, dac tinh cua hd 'ket cau chong-khdl di'vi
die tinh eo hgc eua hd "neo cdt thep - neo cip"
ed sy kit hop Trong dilu kidn dit da mdm y l u
bd rdi, dit dd xung guanh dydng Id biln dang
Idn, sau khi khai ddo ldp tCrc sy dyng neo cap,
cd t h i do dd ddn ddi cua neo cap bi vygt gud
gidi han md dan toi phd huy Do dd, d giai doan
diu, ddo Id th] ehi ldp dgt neo ed't thep, thdng gua
tdc dgng gia cd eOa neo edt thep ma hg kit c l u
chdng-khdi dd da cd khd nang chju tdi nhit djnh,
eho phdp phdt sinh biln dang, gidi phdng mdt
phin biln dang trong khdi dd, d i t da trong pham
vi biln dgng nhit djnh cd t h i giO gin t y thdn dn
dinh[3i Tuy vdo mye dg bien dgng eua d i t dd
xung guanh md tdng Idn, khd ndng chju tai vd dg
dn dinh cua hg "kit ciu chdng-khdi di" giam di,
trydc khi tinh t y I n djnh cua hg "kit ciu
chdng-khdi di" dat d i n gidi han, khi biln dgng dy cua
dit da nhd bing dg dan ddi eho phep cIJa neo
cdp, liic ndy tiln hdnh ldp dgt neo cdp se Idm
giam nhd ydu clu v l dg ddn ddi cua neo cdp ddi
vdi dit dd, bdo dam giO eho hg "kit ciu
chSng-khii ifd"dn dinh (hinh 1 b) Thdng gua hd neo cot
thdp k i t hgp neo cdp, se ndng eao dygc lye
chdng giCf, giam biln dang eua d i t dd Neo kit
hop neo cdp phdt huy uu t h i I l n nhau, dydng
Id d giai dogn ddu khai ddo thi tinh deo cua neo
thydng se dygc phdt huy, d i n giai dogn sau
khai ddo thi tdc dgng treo cua neo cdp se dygc
phdt huy hai tinh chit ndy tyong ho bd trg oho
nhau, Ily ddi bd trg ngin, t y dg, md eai thidn tinh
ndng ehing giy tdng t h i cua hg thdng, dgt dygc
mgc dieh khdng c h l sg- biln dgng Idn eua dat
dd Do dd tdc dgng ching giir ndy cd t h i ggi Id
tdc dung chdng giy tyong hd bo trg neo kit hgp neo cap Thdng gua tdc dgng ndy Idm tdng len tinh on tfinh vd khdng c h l s y phdt trien nCrt ne trong khdi dd xung quanh bao dam an todn trong san xuit
3 Nghien CLPU hodn thien k i t edu chdng giu* cdng trinh n g l m k i t hQ'p neo vd neo cdp Chong giO' dyong lo la khdng c h l dat dd xung quanh biln dgng va duy tri bao vd dydng 16 Trong trydng hop chung ngodi cdc ylu td dia
ky thudt qud trinh hinh thdnh tdi tnpng tae dgng Idn k i t c l u chdng giy cdn chju sy anh hydng rit Idn cua mdt logt cac y l u td nhy; thdi diem ldp dyng kit eiu chong; dd cung cua kit clu chong;
do linh hogt cua k i t c l u ehdng vd nhOng y l u t i khdc[2i Xu t h i hign nay Id sO dung kit clu ehdng giy chii dgng (tang khd ndng mang tai ciia khdi dd bao quanh cdng trinh nglm coi bd ph^n chju tdi chlnh la khdi dd tao thdnh hg vd ehdng-khli dd nhy neo, bd tdng phun, bom ep vu'a gia eydng ) Chdng giQ" bdng neo cd higu qua khdng c h l dygc b i l n dang cua d i t dd bao quanh hay khdng, ehii y l u la d logi hinh kit cau neo vd cdc tham s l chong giy dd hgp ly hay chya Trong dieu kign d i t da nhit dmh, mgt do neo dydng kinh neo, chieu ddi neo do ddi gia
cd cua neo md tang Idn thi biln dang eua dit
dd bao quanh dydng Id se gidm d mye dg khdc nhau Trong qud trinh thilt k l eIn tong hgp xem xet gid thdnh chong giu' vd higu qua chdng giiJ ddp yng ydu c l u Idn nhit d ca hai phyong dign
ky thugt vd kinh t l
3.1 Phin tich sv sip Id cue bd xiy ra khi
chdng bang neo cdt thep ket hap neo cap
Thyc td' tai mgt so dydng Id chdng bing neo
k i t hgp neo cdp da xdy ra sy phd huy cgc bp
Od eao Id ndc eua dydng Id Idn hon dg sdu gia
e l cua neo thydng nhyng nhd hon dg sdu gia
c i eiia neo cdp Sau khi Id ndc dgi da sd neo cdp bi dirt, dogn gia c i neo cdp vdn lyu trong khii dd cdn Igi d trdn ndc cdn todn bd neo thydng bj roi xudng than neo thydng vd phg kidn van tit Nguydn nhan ehu y l u Id ndc Id: Trong qud trinh ddo Id I l p d§t neo vd neo cdp cdng vdi thi edng Id chg, md men d y Cmg lyc khi
i l p dgt neo Id lOON.m, sinh ra dy i>ng lyc rit nhd (10 - 15kN) khdng ed tdc dyng ching giO chu ddng khdng t h i khing c h l hidu qua dit da
Trang 3b i l n dgng thdi ky d i u Nhyng d y yng lyc eiia
neo cdp r i t cao (khoang 80kN) d i n tdi tai trgng
thdi k^ d i u ching glQ' t$p trung vdo neo cdp cdn
neo cot thep mat dl tdc dgng chu dao chju tdi
Trong qud trinh ddo Id biln dang elp tdc cua d i t
dd neo va neo cap d i u bj keo dan ddng thdi lyc
kdo cung tdng len Nhyng do dan ddi cua neo
cdp r i t thip dd dan ddi eua neo thydng r i t cao
dd biln dgng eiia 2 logi chenh Igeh Idn, khdng
thich ling vdi kha ndng bien dgng eua d i t dd,
trong ca qud trinh ching giy khdng the ddng bd
chju tdi khdng hinh thanh hop lyc idm t i c dd
tdng tro lyc len neo cdp qua nhanh khi lye keo
cila nd vygt qud gidi hgn se bj dCrt cdp d i n tdi
sgp td ndc Id ma neo thydng v i n khdng t i n hgi
gl Cho ndn trong ehing giy k i t hop neo cot
thep vd neo cdp dgt dygc hieu qua ching giir
ly tyong c i n phai phii hop ian nhau kha nang
biln dang cua ca hai logi [4]
3.2 Didu chinh ket du sal thdp, ning cao dd
dan dai cOa nd trong neo cip
Lyc keo dyt cdp vd kdt c^u sol cdp thdp cua
neo cdp ddng vai trd rd't quan trgng Neo cdp khi
Ilp dgt se tgo ra mdt dy Crng lyc can thiet Trong
cdp se xuit hien lyc cdng T Trong pham vl biln
dgng dan h i i quan hd giya T vd dd dan ddi cua
cdp Al Id ty ig bac nhit Cdp dang d trang thdi t y
do, khi gap tryong hop d^t dd biln dgng kjch ligt,
cdp cd the' se bj dan ddi, vygt qud gid th gidi
hgn, khi dd lyc cang trong cdp T > T] [T] -Lyc
kdo dCrt gidi han cua cdp) S y gidn edng ndy phg
thudc vdo tCrng logi cap, cdng nghd c h l tao, tieu chuin san xuit Dg dan dai cua sgi thep neo cdp va k i t c l u cua nd cd m i i quan hg r i t Idn, thing thydng neo cdp van hay sy dgng cdp 1x7
dg dan ddi chi Id khoang 3,5% thich Crng vdi kha ndng biln dgng cua d i t dd, nhyng rit khd thich Crng cung vdi neo eha't deo cdt thdp Ngdy nay logi cdp mdi c h i tgo quy each sgi cap thep Id 1x19, ed nhieu sgi hon, rdt yu vigt ddi vdi ket
c l u cdp thep kieu soi, dg day ddc cua k i t c l u
t i n g t h i vygt xa mat dg k i t c l u cdp thep 1x7 ndng cao dp on djnh, vCra bao dam dd cCrng vya lam tang he s i tinh mem cua cap bdo dam gian tien thao tdc tgi hign trydng, dd dan ddi khdng nhd hon 7% ndng cao thich Crng kha nang biln dgng kich lidt eua d i t dd ndc Id
3.3 Phdi hap diiu chinh lech thdi gian thi
cdng neo vi neo cap
Quan hg tdc dgng tyong hd cua he ehing giy-khii da dygc thd' hidn nhy trong hinh 1 Dydng dgc tinh co hgc cua neo cdp (4) vd
dydng dde tinh eCia he "ket cau chdng-khdi di"
(3) vd dydng dac tinh co hgc cua k i t c l u ching giQ-thdng thydng Id khdng gidng nhau, nang lyc nhan tai cua he k i t c l u ching-khii da Id tiiy vdo biln dang tang Idn thi khd nang chju tai se giam
di Dydng cong 11d dydng ddc tinh khii dd, bleu thi m i l quan hd giya eydng dd ching giy va bien dgng d i t dd Dya vdo nhyng phdn tieh trdn,
n l u dydng dgc tinh cua he k i t e i u ching giy -khii dd vd dydng dac tinh cua neo cap khdng
jBien dang cua dat da|
|)i£n d ^ R cua ddt da|
1 Budng die tinh dit di: 2 Dudng die tinh ching giO kit hap neo vi neo dp Uo - Dich chuyin hi mit dudng Id: 3 Budng die tinh cOa hi kit eiu ehing - khdi di AL -Bddin dii cua neo dp:
4 Budng die tinh neo cip Hinh 1 Quan hi tie dung tuong hi kit ciu ching vi dit di
Trang 4^^^^^Hmh^Hinh 'inh'neo cip'
t h i cung vdi dydng eong 1 giao cat nhau dilu
dd eho thiy ddc l^p su' dgng neo cdt thep hodc
die ldp sO dung neo cdp d i u khdng the khing
c h l dit dd dat dygc i n djnh N l u ehing giy neo
c i t thep vd neo cdp k i t hop, dydng dgc tinh
edng tdc dgng ehing giy 2 vd dydng eong 1
giao nhau, bilu thi ehing giu k i t hop neo cot
thep vd neo cdp da nang cao kha ndng chiu tai
cua hd k i t c l u ehing, tgi dilm giao elt, biln
dgng cua dit dd dgt dygc sy khing c h l bao
dam duy tri dg i n dinh eiia dat dd xung quanh
dudng Id [4] Nhy vdy se ed hai trudng hop:
- Trong tm'dng hop khi neo vd neo cdp ddng
thdi dygc Ilp d^t (hinh la), bdo dam tiln d l
thdnh edng ehing giu' neo k i t hop neo cdp la khi
d i t dd xung quanh dat dygc 6n djnh d i biin
dang Uo nhd hon dg ddn ddi gldl hgn eOa neo
cdp Thda mdn dilu kien tinh i n djnh eua dat dd
thi trong trydng hop ndy ndi ehung Id khd tdt khi
dd cd t h i thdng qua lya chon hgp ly ede thdng
s i vd quy cdch neo d l sir dung neo ddc Igp ed
t h i bdo dam duy tri dd i n djnh eua d i t dd
- Trang tnfdng hgp dydng Id qua d i t dd mIm
ylu vd ndc Id rdi vgn mCre dd biln dang Idn giai
dogn d i u khai ddo dydng Id tiln hdnh ehing giCr
bing neo cot thep, chu y l u dya vdo tinh mIm
eiia neo cdt thep, md giai doan sau khai ddo mdi
phdt huy tdc dgng treo ciia neo cdp Cd nghTa Id,
neo cdp se dygc ldp dgt sau, khi dd, neo c6t thep vd neo cdp khdng d i n g thdi cCing tdc dgng gia eydng, ma Id tyong hS lay ddi b i trg ngan, tCr dd eai thign dygc r i t nhilu tinh ndng ching giQ' ting the hd thing ehing neo, thyc hign dygc tdc dgng khing c h l d i t dd biln dgng Nguyen ly tdc dung tuong ho chong giO nglu hgp lan 2, neo cap lap dgt sau neo cdt the'p (hinh lb) Trong cdc dydng Id dgc via phdn tang sau ktii khai ddo, t i e dd bien dgng cua d i t dd khong ngyng thay ddi, thydng trai qua 3 giai doan: giai dogn anh hydng cua qud trinh dao Id, giai dogn
on iflnh vd giai doan anh hydng cua hogt ddng khai thde Giai dogn anh hydng ciia dao Id trydng Crng suit nguyen sinh phdn bd Igi, tic dO bien dgng nhanh, ydu c l u ddi hdi neo edt thep
vd neo cdp cd do dan ddi khd Idn d l thich ling vdi biln dgng d i t dd, eho ndn, trong thyc t l thi cdng, cung vdi viec thi cdng gyong Id ehg, ndn
c i n tgo ra cho neo cdt thep m i t dy yng lyc kha cao, khdng c h l biln dgng sdm cOa dit dd C6n-neo cdp th) nen thi cdng lap dgt sau C6n-neo cdt thep, khi biln dang e l p tdc chuyin sang biln dgng ehgm d i n , khi dd Id giai doan t i t nhit dd Ilp d|it neo cap
3.4 Phdi hap thuc hiin diiu chlnh dd Idn du ung tuc neo va neo cip
Trong ehing giO k i t hop neo edt thdp vd neo cdp, neo cdt thep khing c h l bien dgng vd tacli Idp dit dd ndc trong phgm vi gia c i ciia nd, tuy vdo biln dgng vd tdch Idp dd't da' ndc Id tdng len,
neo bj dan ddi, neo a trong qud trinh kdo dan,
lye kdo cung tang Idn kha nang khing chl liiln dang d i t da eung tdng len Do phgm vi gia c6 cua neo cdp bao hdm phgm vi gia c i cua neo cdt thep, eho ndn neo edt thep d trong qud trinh kdo dan thi neo cdp cung bj kdo ddn Trong qud trinh thi edng thyc t l nen tgo d y lyc khd Idn eho neo cdt thep, giam thd'p nhat biln dgng vd tdch idp cua d i t dd neo cap nen tgo d y Crng lyc nhd d l
do biln dgng vdn cdn d y trong neo cdp d l thich Crng vdl biln dang va tdch Idp giai dogn sau ciia
d i t dd I"' Cdng thCrc suy ludn dilu kidn phii hgp kha nang bien dgng neo cdt thep va neo cdp nhi/ sau:
Khi khing d y Crng lyc:
Pamax ~ K « Aimax
Pgmax = Kfl Z^gmax
Trang 5K=' nYld'a^,
Khi ed d y ung lyc:
Psmax = Pso + K s A s
Pgmax — Pgo + K g A g
Bat tudn cd hay khdng cd d y ung lye, gid tri
K d i u Id khdng thay d l i , do dd d i l u kipn phii
hgp khd nang biln dgng Id As=Ag, tuc la
dl<^ lA
Trong dd:
Psmax, Pgmax - Khd ndng chiu tai gici hgn cua
neo cdp vd neo cot thdp; Ks, Kg - H# s l nh^n lyc
neo cdp vd neo cot thdp; Asmax, Agmax- Bq dan ddi
gidi hgn cua neo cdp va neo cot thep; ds - 0 u c n g
kinh sgi cdp thep neo cap; n- So sgi thep neo
cdp; dg -Ducng kinh neo cot thep; 5bs,
5bg-Cudng dp gidi hgn v^t Ii$u neo c6t thep vd neo
cdp; U, Ig - Chilu ddi nep cap vd neo cot thep;
5s, 5g- Dp dan ddi cua neo cdp va neo cot th6p;
Pso,Pgo - Dy ung lyc neo cdp vd neo cdt thep
Ndng cao dO b i n cua hp neo cot thep ket hgp
neo cdp d l i vci hipu qua chong giu rat quan
trpng, d y i>ng lyc eua npo ed tdc dgng quylt
djnh, gay ra cho neo mpt d y ung lyc khd len,
d i n g thci, thdng qua t i m dpm, thanh nep vd
nhCmg c l u ki^n khdc, thyc hipn l^uech tdn dy
ung lyc Id phucng phap hij'u hipu nang cao hipu
qua ehing giu neo Phii k i t hgp d u ung lyc hdi
hda giua neo cdt th6p vd neo cdp d l ching giu
d i t da xung quanh dudng Id dugc hipu qua
nhit
4 K i t lu$n
Cdng nghp ching giO su dgng neo cd't thep
k i t hpp neo cdp trong cdc dudng Id md cho thiy
hi|u qua rd r#t Ld m$t logi hinh chong giQ- chu
d|ng, hudng cdng nghe chong giu nay phat trien dya tren hieu i>ng khai thdc t i i da kha ndng mang tai cua khii dd gia cudng Ching giu kjp thci ngan can dugc hipn tugng sdm tdch Icp vd
ed t h i tgo ra dugc d y ung lyc, ndng cao kha ndng chju tai cua dat da xung quanh Dam bao duy tri dp I n dinh eua ducng Id, ndng cao chdt lugng ching giu
Tren cc sd phan tich qua trinh biln dang dat
da xung quanh ducng Id, nhdn t l anh hucng ehu y l u d i n biln dgng phd huy dudng Id ehing neo bao gom: Tinh chat cc hpc cua d i t dd, Cpng suit d i t dd xung quanh, tinh ding nhit lien khoi cua khii dd tilt dipn ducng Id, v$t lipu vd k i t
c l u ehing giO, anh hucng t u ban than Id ehg khai thdc vd Id chg Idn cgn Trong d6, nhung thdng sd' cua hp ket cau neo cdt th^p k i t hgp neo cap Id rdt quan trpng, nhu lua chpn dp dan dai eua cap lam neo; dieu chinh l$eh thci gian thi edng neo cot thep vd neo cdp; dieu chinh dp len
d y ung lye neo cot thep vd neo cap, de sao cho
hp ket eau Idm vipc hi#u qua nha't, phd huy dugc
t i t ca cdc Igi S\em eua hai logi neo Ti> dd, gdp
phin eho vipc (^nh hudng vd nghien cuu sdu de toi uu hda cde thdng s l thilt k l vd thi cdng dao ching, lya chpn hinh thuc vd vd cde tham so ching giu thich hgp, nhdm ndng cao dp on ^inh eua dudng Id, dam bao an todn va hipu qua kinh
t l ky thudt./
rdi li^u tham khio:
[1] Trinh Dang Hung, Ndng Vipt HCing,
Nguyin Thj Thu, (2013) Nghidn c&u su- dung
neo kit hop neo cap trong chong gid cong trinh ngim, mo {J] Tgp chi Cdng nghipp md
[2] Trinh Dang Hung, Chen Chang Hua, Song
Jia Lin, (2012), Active support works in
under-ground mining construction execution and trends
of its application, Proceedings of the 4th Interna-tional symposium on mine safety China Liaoning
Technical University
[3] Zhaoqing Biao, Houchao Jiong.Manian
Jie, (2015), Phuang phap tinh toan vi nguyen iy
bo trq chong giCr neo va neo cip Tgp chi Oai hpc
Cdng nghp moTrung Quoc
[4] Wangfei Hu, (2001), Nghien ciru phuang
phip xic dinh cic tham so thiit ke va ca ly chong giu neo di/ ung iuc trong cong trinh ngam
Dpi hpc Cdng ngh$ Tdy An, Thilm Tay, Tdy An