Tnnmg Dur Dir T o m tSt: Cdng ngh^ chdng giir su dung neo cdt thep ket hgp neo cdp la logi hinh cdng nghe chong giir chu dgng.. Ndm 1996, ky thugt chong giO bdng neo cdp ehit ddo trong
Trang 1I PHI ONG PHAP KH.AO SAT DANH GIA DIEU KIEN DIA CO MO
N A NGUYEN T \ C THIET KE CHONG NEO KET HQfP NEO CAP
TS Trinh Dfing Hirag, KS Nguyen \ an Bac
Viin Khoa hgc Cong nghe Mo - Vinacomin
KS Pham Quy Manh
Ban QLDA Khe Chdm Il-IV-Cdng ty than Hg Long-TKV
Bien tap: TS Tnnmg Dur Dir
T o m tSt:
Cdng ngh^ chdng giir su dung neo cdt thep ket hgp neo cdp la logi hinh cdng nghe chong giir chu dgng V&i nhOng iru diem vugt trdi, day dugc cai Id cdng ngh4 chdng giir rdt ly tuang nhimg den nay vdn chua dugc dp dung rgng rai tgi cac mo than hdm Id Viet Nam A'i/ Irong nhirng nguyen nhdn ca ban do Id khdu khdo sdt ddnh gid phuc vu thiit ke chong giir vdn chira dugc thtrc hien day du va bdi bdn Do do cdn hodn thi^n khdu khdo sdt dank gid phye vu thiet ke, gdp phdn dp diing rgng rdi cong nghe chong giir chu dong ndy
1 M d dau
Ket cau chong giO bdng neo vd neo cdp da
dupe ^p dyng ph6 bien d nhieu nudc trdn the
gidi nhu My Anh, Oe Trung Qu6e Ndm 1996,
ky thugt chong giO bdng neo cdp ehit ddo trong
edc dudng Id md dd dupc nghidn ciru irng dyng
thdnh cdng tgi Trung Quoc tip dd neo ket hpp
neo cdp chat ddo dupc sir dyng rpng rdi trong
cdc md than h i m Id Qud trinh dp dyng logi hinh
ket e i u ch6ng giu ndy eho thiy nhilu uu dilm:
ching gii> ehu ddng d i t dd, gid thdnh khdng
dit, d l ldp ddt, tdng muc dp on djnh cdng trinh
dudng Id hau nhu khdng phdi chong xdn sua
chua Igi Neo cdp c6 kha ndng mang tdi eao
chju tdi ngay sau khi lip ddt, tgo dupc dp irng
Ipc trong neo, cd t h i l i p ddt vdi ehilu ddi bat
ky trong khdng gian chgt hpp Phgm vi dp dyng
rdng, trong cdc dudng Id dpc via than ho$c
trong cdc khu vpc ngd ba, ngd tu d Viet Nam,
cdng ngh0 ehlng giCp bdng neo cdp v i n cdn khd
mdi md, chua dupc dp dyng rpng rdi Mpt so
md cung dd dua vdo dp dyng, nhung cdng tdc
khdo sdt dilu kipn dja eo md chua 6u?(?c thpc
hi^n mOt cdch d i y du vd bdi bdn cho nen cdng
tde thilt k l chua dupc sdt vdi dieu kign thpc te
hi0n tnj'dng Do dd, rat c i n phai khdo sdt ddnh
gid dieu ki0n dja eo md mpt cdch ti mi vd khoa
hpc, d l phye vy thilt k l chong giu- dupc higu
qud nhit, d l ti> dd, gdp phdn thuc day ieng dyng
rdng rdi k i t c l u chong neo k i t hpp neo cap chat
ddo cho cdc md than h i m Id Vi0t Nam
2 Khao sat danh gia dieu kien dja c o md
o l t da bao quanh cdng trinh ngam vd ciing phuc tap, trong dd, bao hdm cdc logi mgt khdng lidn tyc, nhu khoi nirt vd ke nirt sp t6n tgi eCia nh&ng mdt khdng lien tye ndy ldm thay doi
rd rgt d$c trung cudng dO vd biln dgng cua d i t
dd, khiln cho cudng dp cua khoi dd vd m i u dd chenh Ipch nhau khd Idn Do dd, tat cd cdng
vide lidn quan d i n d i t dd d i u e i n phdi du^qtc
hilu rd d i y du ddc trung eo hpc dja chit d i t dd xung quanh Can thiet phai tien hdnh cdng vigc kiem tra cudng dp, thdnh phin vdt chit vd c l u triic d i t dd Cdc hgng myc kilm tra ndy da dupc cde don vi thilt ke Trung Quic sir dyng Id m0t
hd thing do dac kiem tra nhanh dieu kipn d i t dd tgi hipn trudng Npi dung edng vigc tien hdnh kiem tra ehu y l u nhu trong bang 1
2.1 Kiem tra nguyen vj cuang dQ dit di
a) Phtrang phap do luang
Sudyng phuong phap lo khoan sdu tiln hdnh kilm tra cudng do dat dd xung quanh dudng Id Phuong phdp ndy da cd nh&ng uu dilm nhu sau: (1) K i t qua do dgc khd g i n vdi thyc t l
d i t dd; (2) cd kha ndng do dgc dupc cudng dO
d i t dd than mem y l u bd rdi md khdng t h i l i y dupc m i u ; (3) ed kha nang phdn tich vd do dgc cudng dO d i t dd khdng ciing trong Idp, khdng cung dp sau trong lo khoan; (4) dyng ey thao tdc khd don gidn, cd t h i do dgc d p toe; (5) cd the thir nghipm kieh thude Idn tgi hign trudng r i t kinh t l so vdi nhung thiet bj khde
Trang 2^
Bang ) Bo rfac kiim tra diiu ki^n dia ca tnd dit di xung quanh duang Id diin hinh
N^i dung kiem (ra Phirong phap do d$c
Cudng dQ d i t dd
C l u tnJc d i t dd
K i l m tra nguyen vi
thdm dd tiep xiic l6
khoan Soi tham do Id khoan
Vl tri 16 khoan
Noc vd hong 16
Noc to
£>d s a u
l6 khoan (m)
10
10
Dudng kinh
lo khoan (mm}
56
28/56
Ghi chd
K i l m tra nguydn vj, khdng
c i n l i y ldi phdn dnh chfln
th^t c u d n g dp d i t 06
N i m rd ty my tinh trgng phat t n l n khe ni/t
Xae djnh cuiyng dO dat da trong l5 l<hoan
du-oc tien hanh nho trong hinh 1 Mot tram do hai
16 tthoan: Tien h^nh i<hoan mot i6 Ithoan vuong
g6c vdi dat da phan giOa noc id difdng Itinh io
khoan 56mm d0 sau 10m, dung de do iu'ong
cu'6'ng do d^t da nbc id; l<hoan mot io i<hoan
ph^n giifa ben hong 16, dirirng l^inh 56mm, do
sSu 10m, di do cu^ng dO cua via than hoac dat
di phia hdng id
DSn ti^n cua Piston d^u thdm do hogt dong
trong diu cao ip sinh ra djch chuyen l<hien doan
d^u cua i^im tham d6 ip vio thanh i5 lihoan
Dich chuyin cua l<im thSm d6 do dung eg do chi
th| dich chuyin bilu thj Ditiri tie dung cua liim
tham d6 trodc l<hi thdnh lo Ithoan dat toi ap life
pha huy giOi han, kim tham d6 dirng im khOng
djch chuyin, tiiy vao sy tang l§n cua ap iyc, kim
tham d6 tac dung l§n thSnh i l khoan se nhanh
ChOng dgt d i n ap lyc gioi han, dat da thanh 16
khoan se bj pha huy, ding h i dyng cu do djch
chuyin kim tham db d$t ngot ntiiy I6n, luc niy
ding h i ap lyc cua bom se ghi lai gia tn ap lyc
cao nhit do dirtfc tai dilm ndy cua d i l da thanh
l l khoan Qua tinh toan, c6 I h i xae djnh du'oc
cif o'ng dp khang nen don tnjc dat da 6 vj tri niy
b) Thiit bi do lu'dng Sir dung WQCZ-56 d l l i p dgt xae djnh
cydng dp dat da qua 16 khoan nhd (hinh 2) Sen hanh kiem tra cydng do dat da Thilt bj ndy stf dyng Id khoan dydng kinh nhd, cd t h i tiln hinh nhanh chdng, do dac cydng dp d i t da xung quanh vdi mdt di$n tich kha Idn Thilt bj niy dypc to hop tif d i u tham dd, chi thj djch chuy4n kim tham dd, cdt l i p dat, bom cao ap Th6ng
s i ky thu^t CO ban ciia thilt bj do lydng:
- Oudng kinh |6 khoan 56mm
- Dp sau tham dd Idn nhit 30m
- Cd t h i do cydng dp Idn nhit tdi 140MPa
c) Bi tri tram do vi s6 Itfifng
Hgng myc dy tinh trong dydng 16 Sic tnfng
ap dyng phyong an se lam 6 lo khoan kilm Ira nguyen vj cydng do d i t da
Khi do dgc, trong Id khoan kilm tra mli ao?n 300-500mm liy mdt mat c i t kilm tra, mli mjl cat xae dinh 3 dilm, lay gia trj tmng binh cija3 diem iam gia trj ap lyc tdi han cua dit da cua vj tri mdt c i t nay Sau khi hodn t i t kilm tra t o *
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Hinh I.SadS nguyin ty xic dinh cuong dg dat di
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Hinh 2 Thiit bj kiim tra curing d( dil di
Trang 3Dil un cua lo Idnw (m) —
-fn>staaata
a Kit qua kiim tra t^i ch& (nguydn vi) b Ket qua kiim tra tai ch6 (nguydn vi)
cudng dg dit da ndc cucmg dg tnj than hdng Id
Hinh 3 Kit qud kiem tra cucrng J dit da ndc va hdng Id
Hinh 4 Hg thing quan chdc toan cinh l5 khoan
b0 dilm do, chuyin doi ra cudng dp khdng ndn
don tn,ie cua moi mgt cdt kiem tra ding thdi ve
ra dudng cong phdn b l eudng dp theo chieu
sdu eua lo khoan
Trong hinh 3 Id mdt vi dy dudng cong k i t
qud kiem tra eudng dp d i t da ndc vd hdng cua
dudng Id dpc vfa than Dudng cong nay cimg
vdi k i t qud quan trde k i t cau dat tuong ung
nhau, hieu rd hon tinh khdng dong nhat cua d i t
dd kit c l u , tdch Idp, ddi phd huy doi vdi mirc
dp dnh hudng ciia cudng dp dat dd Anh hudng
eua tinh ding nhat doi vdi cudng dp dat dd, dua
ra mdt dudng loi hipu qud trpc quan
2.2 Kiim tra ciu tnic dit di
a) Phuong phip va thiit bj do ludng
Sir dyng mdy soi l5 khoan dign tu kilu todn
cdnh (Hinh 4) quan sdt tinh hinh phdn b l c l u
tnJc d i t dd thdnh l6 khoan Phuong phdp ndy
vd ket qui quan chic ciu true dit da Id khoan
khdng chi quan sat trong lo khoan kiem tra mpt each chuydn nghidp, md cdn trp giup quan sdt
lo neo va neo cdp, thudn tidn, nhanh ehdng, gid thdnh re, thich hpp cho quan sat nhanh dipn tich Idn cau true dat da xung quanh dudng Id Sau khi khoan xong lo, dau tidn mang mdy soi cdm vdo trong lo khoan Lo khoan cd t h i Ipi dyng lo khoan kiem tra dja irng lue (dudng kinh 56mm) hogc lo khoan neo edp (dudng kinh 28mm) tiln hdnh quan sat k i t e i u d i t dd
b) Bo tri diem do va so lietyng
Dpa theo hgng myc ydu c l u , tiln hdnh kilm tra hipn tnfdng, tim hilu tinh trgng phdt triln khe nirt cua dat dd phdn doan tinh dong nhat cua dat dd Tiiy theo ydu c l u cua thilt ke vd dieu kipn ey the cua cdng trinh ma xae djnh s6 lupng cdc lo khoan kiem tra nguydn vj c l u triic
d i t dd xung quanh eho dudng Id Ipa chpn dp
KHCN.M S6 1/2017 • CNKT H.AM LO
Trang 4dyng chong neo
2.3 Thu nghiem kha ning iim viec cua neo
vi phin tich thinh phin vat chit dit di
a) Thir nghiem kha nang iam viec cua neo tai
hien tnrdng
Thif nghiem kha nang lam viec cua neo tgi
thyc t l hi^n tnrdng la cdng viec eo ban tiln hanh
tnfdc khi thilt ke chong neo, dac biet la ddi vdi
he thong chong giir neo va neo cap dy ifng lyc
Idn, kha nang iam viee cua neo Id rat quan trpng
anh hydng tdi thdnh cdng hay khdng eCia thilt
k l chong neo Quy phgm thilt k l chong neo
Trung Quic quy djnh "tien hanh thir nghipm nJt
nho neo theo yeu eau chong giy tai hien trydng
hogc trong dieu kien dit da tlfong ty, moi lan
khdng it hon 3 thanh neo" Dya theo ket qua thif
nghidm d l phan doan tinh kha thi cua neo trong
dit da Do dd, trydc khi thilt k l ehlng neo, rit
c i n phai dyoc thir nghipm kha nang lam vipc
cua neo trong dit da, de lya chpn hpp ly cic
tham s6 CO b i n va hinh thirc ehlng giCr
b) Phin tich thinh phin vat chit vi chit kit
dinh trong dit di
Thdng qua phan tieh thanh phan khoang vdt
dit da xung quanh va chit dinh kit trong d i t
dd, d l hilu ro todn dipn hdm lyong va thdnh
phin khodng vgt dit dd xung quanh, d l tip dd
phdn dodn dgc tinh tryong nd vd mem hda khi
gdp node ciia d i t dd, qua d6 djnh hydng thilt
k l ehlng gio vd quylt dinh ky thudt thi edng
Thdng qua lya chpn bipn phdp ky thudt hyp ly,
gidm hit mirc cd t h i anh hu^ng ciia nyde d l i
vdi tinh I n djnh cua dat da, gidm thilu mipc do
khd khdn trong chong giif 16 Thdng qua vipc
tiln hdnh liy mau tgi hipn tnfong va sir dyng
phyong phdp phan tich X-quang tien hdnh plidn
tich thdnh phan khodng vdt
3 Nguyen t i c t h i l t ke chong neo
Hi§n nay, cdng tdc thilt ke ehlng neo dang
dope dp dyng d cdc md h i m Id viing Quang
Nmh chya bdm sat difpc hit eac nguyen t i c
thilt k l C i n dya vao tac dyng tifong ho giOa
dit dd vd ket eau ehlng, dgc dilm di/dng Id,
yeu cau cy the eiia cdng trinh, khi thiet k l eiri
phai chil y cdc nguyen tie thiet ke ching giy
dydi ddy:
(1) Nguyen tic ching giif mot tan Ching
neo n6n thiet k l sao cho mdt i l n ehlng giif cd
hipu qua khong che d i t dd bien dgng, tranh vi4c phai chong giy hay chong xen Igi nhilu Iln M^ khac, theo yeu cau san xult an todn, hi|u qui, thuc day dao Id nhanh, dam bao dydng 16 in ffinh trong ky hgn sir dyng de phye vy khai thac, khdng phai siia chOa lai Ben cgnh dd, gyong
Id vifa dyoc khai dao Igp tire tien hdnh ching neo hieu qua se r i t tot, cdn n l u de dat dd bj bo rdi, tdch Idp, thi hipu qua chong giy se bj anh hydng rd ret
(2) Nguyen tic khuich tin dtf img tifc vi cao dii img life Dy irng lyc la nhan to quan trpng
trong chong giO neo, la tham s i cho sy khdc bipt giya chong bj dong hay la ehlng chii dOng, chi CO neo cao d y ifng lyc mdi thdt sy Id ching giif chil ddng, mdi cd the phdt huy day du tdc dyng ehlng giO ciia ned Mpt m$t, c i n cd bi^n phdp hi^u qua gdy ra chp ned mpt dy irng lire tifong doi idn; mgt khdc, thong qua t l m d^m,
thanh npp, nhirng phy kipn khdc dh thye hi0n
khuech tdn dy irng lyc cua neo, md r$ng phgm
vi tdc dyng ciia d y ifng lyc neo, ndng cao dO cirng t i n g t h i cua h§ thong gia co
{3) Nguyin tic 3 cao 1 thip Tire Id cyftng
dp eao, dp cimg Idn, tinh kha thi cao vd m§t iJi thip O l ndng cao codng dp neo (tdng dydng kinh neo hodc ndng cao cydng do v|t li^u thanii neo), dd cirng (ndng eao dy irng lyc neo, tdng chilu ddi neo hogc gia c l todn than), bdo dim
d l tin cdy eiia hp thing chdng giif, giSm m^t di ehlng giy, giam s i lypng neo tren mdt don vj dipn tich, nang cap toe do ddo chong Id
(4) Nguyen tic cuvng do tiri han vi dO cimg
Hp thing ehlng neo ton tai dp cirng va cifdng
dp chong gio tdi hgn, n l u nhy dp cimg vl eydng dp ching giir nhd hon gia tn gidi hgn, du'dng Id thdi gian ddi d vdo trgng thdi khing
I n dinh, d i t dd pha hiiy, bien dgng khdng difpc khong c h l hipu qua Do dd, thilt k l dd cirng vl cydng dp ciig hp thing ching neo nen Idn hon gig trj gidi han
(5) Nguyen tic phii htfp tuong hi Cac phv
kipn neo bao g i m t l m dpm dai 6c, thanh nppvl cac tham so khdc, phli hyp tyong ho tinh ndng
CO hoc, d l phdt huy t6i da tdc dyng ching giO long t h i cua hp k i t c l u ching giif
^ (6) Nguyin tic khi thi trong thao tic Thilt
k l chong neo c i n phai cho thiy tinh hi$u qui
KHC VM SOI 2 l i r - C S K T I U M L O
Trang 5trong thao tdc vdn hanh, thudn Ipi cho thi cdng
vd ndng eao ^ dp dao chong Id
(7) Nguyen tic bao dim hieu qua chong giir
va ning cao mirc do an toin trong qui trinh thi
cdng: chi phi hop ly gdp phan lam ha gid thdnh
tong the ddo chong Id
4 Ket ludn
Thpc t l chong gi& su dyng neo cot thep k i t
hpp neo edp chit deo d cde nude phdt trien
nhu Trung Quoc da cho thiy hipu qua rd ret
Ld mpt loai hinh chong gi& ehu dpng, khai thdc
toi da kha ndng mang tai cua khoi dd, kip thdi
ngdn can dupc hien tupng sdm tdch Idp va cd
t h i tgo ra dupc d u ung luc, ndng eao khd ndng
chiu tai cua d i t dd xung quanh, ddm bao duy tri
dO I n djnh cua dudng Id, ndng cao chat lupng
chong giu
Vdi nhung uu diem co ban cua neo cdt thep
k i t hpp neo cdp chat deo d l ndng eao higu
qud :;hong giu edng trinh ngim, can thiet phai
phdt triln dp dyng k i t cau chong ndi tren trong
thuc t l cac md ham Id Viet Nam D l phdt then
dp dung, can thuc hi$n phuong phdp khao sdt ddnh gia va bam sat ede nguyen t i c thiet ke ndi trdn, dong thdi hoan thien quy trinh thilt ke Qua dd gdp phdn nhdn rdng vd phdt trien dai trd cdng nghd chong gi& nay eho cae md than
h i m Id Viet Nam./
Tai lieu tham khao:
[1] Trinh Dang Hung, Ndng Viet Hiing,
Nguydn t h j Thu (2013), Nghiin cuv si> dyng
neo kit /7pp neo cip trong chong giir cdng trinh ngim md[J] Tgp chi Cdng nghiep mo
[2] Trinh Dang Hung, Chen Chang Hua
S c i g Jia Lin (2012) >Ac(/Ve support works in
underground mining construction execution and Trends of its application, Proceedings of the 4th International symposium on mine safety China
Liaoning Technical University
[3] 1104-2009, Cpng hda nhan dan Trung
Hoa Quy pham ky thu$t chong glii' neo 16 than
MT/T
Method for investigating and evaluating the mine geomechanical conditions and the principles for designing works in supporting operations with using reinforcing anchors and cable anchors
Dr Trinh Dang Hung Eng Nguyen Van Bac
Institute ofMuiing Science and Technology — Vinacomin
Eng Pham Quy Manh
Ha Long coal company
Sunimar>':
Supporting technology « ith using reinforcing anchors and cable anchors is an active supporting one K 1th many dominant advantages, this has been considered as an ideal supporting technology, hul so far, is has noi been widely applied lo Vietnam underground coal mines One of the main causes is that, the investigation and evaluation worLs for serving the design in supporting operations are insufficient Therefore, it is necessary lo improve the investigation and evaluation txniks for serving the designing works in this field