KHAO SAT THIET KE XAY DUNG TAI BIEN TRl/dT LCf DAT DA TREN SlTClN DOC Dl/CiNC GIAO THONG VUNG MIEN NUI TINH QUANG BINH ThS NGUY§N DCfC L?™ GS , TSKH NGUYEN THANH'''''''''''' 1 Sd Khoa hgc va Cong nghe tinh Qua[.]
Trang 1KHAO SAT - THIET KE X A Y D U N G
TAI BIEN TRl/dT LCf DAT DA TREN SlTClN DOC Dl/CiNC
GIAO THONG VUNG MIEN NUI TINH QUANG BINH
ThS NGUY§N DCfC L?™
GS., TSKH NGUYEN THANH'''
1 Sd Khoa hgc va Cong nghe tinh Quang Binh
2 Dai hgc Hue
Tom tat: Trong thai gian qua, tren cac tuyen
duang giao thong vung mien nui tinh Quang Binh, dac
biet vao mua mua lu thuang xay ra hien tugng trugt la
dat da tren sudn doc, mai doc (goi tat la suan doc),
lam ach tac giao thong, anh huang den luu thong
hang hoa, pha huy nhieu doan duang va cong trinh
giao thong quan trong gay thiet hai lan ve kinh te xa
hgi va cong trinh
Bai bao gidi thieu nhdng ket qua nghien ciru mdi
nhat ve tai bien trugt la dat da tren suan doc duang
giao thong vung mien niii tinh Quang Binh
1, Gidi thieu
Tinh Quang Binh nam d Bac Trung Bd Viet Nam
vdi dien tfch tu nhien 8.065,26 km^ dan sd nam 2009
la 858.802 ngudi
Quang Binh cd vj tri dia ly dugc gidi han bdi cac
toa do dia ly d phan dat lien la: diem cue Bac: 18°
05'12" vTdd Bac; diem cue Nam: 17°05'02" vTdd Bac;
diem cue Ddng: 106°59'37" kinh dg Ddng va diem cue
Tay: 105°36'55'kinh do Ddng ,
Tren dja phan viing mien nui phia Tay tinh Quang
Binh cd nhieu tuyen dudng giao thdng quan trgng di
qua nhu dudng Hd Chf Minh (HCM), dudng xuyen A,
dudng qudc Id 12A, cac dudng tinh Id: TL 10, TL 11,
TL 16, TL 20 Cac tuyen dudng nay la tuyen giao
thdng huyet mach quan trgng, cd y nghTa chien luge
trong tat ca cac ITnh vuc: chfnh trj, an ninh qudc
phdng, kinh te va van hoa - xa hdi cua dat nude, cua
khu vuc mien Trung ndi chung va tinh Quang Binh ndi
rieng
Ndi dung bai bao la ket qua nghien curu tai bien
trugt Id dat da d 197 diem sut, trugt (bao gdm ca ddng
biin dat da) thudc tuyen dudng TL 10, TL 11, dudng
HCM (trU nhanh Ddng, tU km 847+120 den km 942 +
402, tu km 00^ +00 den km 167^ + 200 thugc nhanh
Tay) va dudng qudc Id 12A (doan km 104 den bien
gidi Viet - Lao tai cCra khau ChaLo - km 142)
2 Dac tfnh dja chat cong trinh cac thanh tao dait da cau tao cac khoi trUdt chu yeu
Qua ket qua dieu tra, khao sat va thf nghiem cd the tach dat da cau tao cac khdi trugt vung nghien curu thanh 2 thanh tao chinh sau dSy:
Tang da gdc (tang dudi): chu yeu la cac da phien set, da set bdt ket, da bdt ket, da vdi set bj phong hoa vUa den manh Phan Idn mat Idp cOa da gdc cam ddc xudng dudng (thuan hudng) va ddng thdi chung chfnh
la mat trugt cua khdi trugt
Tang phu: la tang dat da da bj phong hoa manh thanh dat cd thanh phan chu yeu la set pha lln cat, dam, san, ft hon cd set, va cd be day bien ddi Chung la san pham phong hoa tU nhieu loai da gdc khac nhau Trong dieu kien tu nhien, dat co sUc khang cat cao nhung khi bao hoa nude sire khang cat giam di
rd ret Ket qua thf nghiem mau dat lay tai cac vj tri trugt cua vung nghien cUu cho thay, sure khang cat cCia dat
d trang thai bao hoa nude cd the giam gan hai lain so vdi dat d trang thai tu nhien khdng bao hoa nude
Ket qua thf nghiem tfnh chat cd ly dat tan - sudn tfch phat trien tren da gdc d 10 diem trugt Idn nhat dac trung va dai dien cho 10 he tang tuong irng, cu thd nhu sau:
- D/en? trWcft km 111 + 583 thugc he tang Rao Chan -D,rc
He tang Rao Chan chi phan bd trong pham vi nghien ciru tU km 108 +815 den km 114 + 000 dudng 12A; tu km 861 + 225 den km 862 + 692 va tU km 886 + 140 den km 887 + 389 dudng HCM Be day tang phii bien ddi tU 2 m den 5 m, trung binh 3 - 4 m, thanh phan tang phu chii yeu la dat set pha lin dam san Diem trugt nay cd chieu day tang phu trung binh h = 3
m va gdc ddc mat trugt binh quan p = 38°
- Diem trWcft Km 114 + 251 thupc he tang Ban Giang • Z7,.^ bg
He tang Ban Giang ph§n bd rdng trong pham vi nghien ciru tU km 104 +350 den km 108 + 815, tU
Tap chi KHCN Xdy dung - sd 312010
Trang 2KHAO SAT - THIET KE XAY D U N G
km1l4 + 000denkm 114 + 841, tU km 117+060 den
118+162 dudng 12A; tU km 860 + 779 den km 861 +
225, tu km 863 + 919 den km 866 + 387, tU km 874 +
237 den km 875 + 486, tU km 894 + 987 den km 895 +
981, tu km 12U 410 den 12^ + 770, tU km 22^+ 680
den 26^ + 125 dudng HCM Be day tang phii bien ddi
tu 4 m den 12 m, trung binh 8 -10 m, thanh phan tang
phii chii yeu la dat set pha lan dam san bj phong hoa
manh Diem trugt nay cd chieu day tang phii trung
binh h = 6 m va gdc ddc mat trugt binh quan (5 = 25°
- Diem trupt km 124 + 163 thupc he tang Bai Dinh •
J^.2 bd
He tang Bai Dinh phan bd rdng va Idn nhat trong
pham vi nghien ciru tU km 120 + 467 den km 122 +
585, tu km125 + 300 den km 125 + 670, tU km 128 +
486 den 133 +'300, tU km 134+800 den 142 dudng
12A va hau nhu vang mat tren cac tuyen dudng HCM,
TL 10 va TL 11 Be day tang phii bien ddi tU 3 m den
10 m, trung binh 7 - 8 m, thanh phan tang phii chii yeu
la dat set pha lan manh dam vun cat ket, bdt ket bj phong hoa manh Diem trugt nay cd chieu day tang phii trung binh h = 5 m va gdc ddc mat trugt binh quan
p = 30°
- Diem trwat km 127 + 000 thupc he tang il/luc Bai •
Dig mb
He tang Muc Bai cung phSn bd rat rdng Idn trong pham vi nghien cUu tU km 104 + 000 den km 104 +
350, tUkm 115 + 841 den km 117 + 060, tU km 118 +
162 den km 120 + 467, tU km 122 + 585 den km 125 +
300, tu km 125+ 670 den 128 +486 dudng 12A va tU
km 923+003 den km 924+394 dudng Hd Chf Minh Be day tang phu bien ddi tU 4 m den 12 m, trung binh 8
-10 m, thanh phan tang phii chii yeu la dat set pha lan dam san da gdc bj phong hoa manh Diem trugt nay
cd chieu day tang phu trung binh h = 6 m va gdc ddc mat trugt binh quan p = 23° (anh 1 va hinh 1)
Anh 1 Iraqi dat da tai km 127 + 000 duang 12A (03/10/2009)
MAT CAT t)!A CHAT CONCi TKINII KM 127+00 - J)LrON(; I2A
TY Lfc: l/3((0
( l l t i C I A l : Sci plia tail - sLion ikli luii d;liii san mau Da pillion sci mau n^u do - ndu v i n j
f:^:Tv;Ij lieiaiif Mut Itai
•'hung hua villi - manh 22f III!
224 01)
222110 22(),(H) 2IK 00
2 Ifi 00
212 00
210 011 I
im.m J
206.0(1 I
2(I4.(M) J
202.0(11
: x a m v j n ^ - tidu
~ * " ^ T r i i i i t i h J i dtio t i ^ n j ; , _ _ Set pha t a i l ' suuii l i c h h\ii ditm san, m a u •'• ] x ^ m vikni; - nflu
' ^ " ' I r a i i g t h a i deo chiiy
9A9
• J i ' ' ••; _
\ D2gmb
Kb»;int! t a i h ( i n ) | 20.96 '
lie Iiy liajf pbii ituoii Wnh = (,()m
Ci,k- ,nii ,l,lc.40« (1,,, ,1,1, „ „ , „ „ , 23 , „ , j ^ „ , „ ,|j ^^^ , j j b Hinh 1 Mat cat dia chat cong trinh tai diem trugt km 127+ 000 duang 12k
Tap chi KHCN Xdy dipig - so 312010
Trang 3KHAO SAT - THIET KE XAY DUNG
- Diem trWcft km 134 + 0400 tiiupc he tang Bac Scfn
• C-Pbs
He tang Bac Sdn trong pham vi nghien ciru thugc
dudng 12A, chi phan bd tU km 133 + 300 den km 134
+ 800, cdn tren tuyen dudng HCM thi phan bd rgng, cu
the tu km 862 + 904 den km 863 + 919, tU km 867 +
280 den km 868 + 814, tU km 879 + 832 den km 880 +
106, tu km 3^ + 110 den km 4^+770, tu km 12^ +250
den km 12^+410, tU km 12^ + 770 den km 15^+ 770,
tu km 16^ + 953 den km 17^+ 749 va tU km 28^ + 077
den km 29"^+ 732 dugng HCM Be day tang phii bien
ddi tu 3 m den 15 m, trung binh 10 -12 m, thanh phan
tang phii chii ye'u la dat set va dat set pha l§n dam
san Diem trugt nay cd chieu day tang phii trung binh
h = 8 m va gdc ddc mat trugt binh quan p = 23° (ddi
vdi bac I - bac dudi) v^ h = 5 m, p = 28° (ddi vdi bac II
-bac tren)
- Diem trWcft km 930 + 500 thupc he tang Dong Thg
•D^-Djfrdt
He tang Ddng Thg phan bd tU km 855 + 940 ddn
km 857 + 831, tU km 917 + 387 ddn km 923 + 003 va
tu km 924 + 394 den km 936 + 062 dudng HCM; Hg tang nay hoan toan vang mat tren tuyen dudng 12A,
TL 10 va TL11 Be day tang phu bien ddi tU 1 m den
12 m, trung binh 4 - 8 m vdi thanh phan chii yeu la dat set pha lan dam san mau nau, xam bac; tang dudi la
da cat ket mau xam sam, phong hoa vUa - manh thudc
he tang Ddng Thg Diem trugt nay cd chieu day tang phii trung binh h = 6 m va gdc ddc mat trugt binh quSn
P = 27° Day la diem trugt cd tai hoat ddng (anh 2 va hinh 2)
Anh 2 TrucA dat da tai km 930 + 500 dudng HCM (10/11/2006)
266.00
2 6 2 0 0
2 5 8 0 0 254-00 250.00 246,00 242.00
238 00 234,00 230.00
22600
222 00
2 1 8 0 0
MA r CAT BIA C H A T CONCJ TRINH KM 930+500 • B U d N ( ; HO CHI MINH
TY Lfi: 1/400
C H O G I A I :
Sot [iha tdn - fiUim tich Un il il&m- tang miu
r ,',, <• ! Xiim n^u, xam hac I—^ • Trang thai deo timg ilij'n deo mtfm
I Cat kijl mau xam sam - HO t^ng DOng Tho
I ^^ Phong hoa vua manh
cdQ
^-11
:> LK3
; TCn 16 khoan Khoang each (m)
[ h6 diiy [^ng phu irung binh = 6.0m
\G6c m^i drfc =3^'; G6c drtc mat trucil =21'\ C6c cSm da grtc =25"
> LK2
:_TZZ
<» LKI
Hinh 2 Mat cat dia chat cong trinh tai diem trugt km 930 + 500 dudng HCM
Trang 4Oi-Wl - i n i C I KC AMY u u N G
- Diem trWcrt km 46' + 600 thupc phWc he TrWdng
Sc/n-GaC^ts
PhUc he Trudng San phan bd tren dudng TL 11 va
doan tu km 43^^ + 300 den km 56 ^ + 796 dudng HCM
va vang mat tren tuyen dudng 12A va dudng TL 10
Be day tang phii bien ddi tU 0,5 m den 4m, trung binh
tu 2 den 3 m vdi thanh phan chii yeu la Idp set pha lan
dam san mau nau xam, xam vang cd ngudn gdc tan
tich Tang dudi la da magma gdm cac khoang vat
thach anh, fenpat, mica cd mau xam trang bj phong
hoa vUa - manh Diem trugt nay cd chieu day tang phii
trung binh h = 3 m va gdc ddc mat trugt binh quan p =
36°
- Diem trWcft km llff + 000 thupc phu he tang
Long Dai 3: O3 -5, idj
Phu he tang nay phan bd tren dudng TL 10 va
doan tu km 83^+ 128 den 90^+069, tU km 107^+715
den 119^ + 295 dudng HCM va hoan toan vang mat
tren tuyen dudng 12A, TL 11 Be day tang phu bien
ddi tu 1,0 m den 6m, trung binh tU 3 den 4 m vdi thanh
phan chii yeu la Idp set pha lln dam san mau nau
xam, xam vang cd ngudn gdc tan tfch Tang dudi la da
phien set mau nau xam phong hoa manh, ddi chd lan
dat cd chieu day Idn Diem trugt nay cd chieu day tang
phii trung binh h = 4 m va gdc ddc mat trugt binh quan
p = 33°
- Diem trWcft km 12 f + 000 thupc phu he tang Long
Dai 2: Oj-Si Id 2
Phu he tang nay phan bd tren tuyen dudng TL 10,
TL 11 va doan tu km 26^ + 125 den 210^+010, tU km
32^ + 682 den 33^ + 050, tU km 39^ + 232 den 39' +
922, tu km 119^+295 den 130'+ 739 dudng HCM va
hoan toan vang mat tren tuyen dudng 12A Be day
tang phii bien ddi tU 0,5 m den 4m; Trung binh tU 2
den 3 m vdi thanh phan chu yeu la Idp set pha lin
dam san mau nau xam, xam vang cd ngudn gdc tan
tich Tang dudi la da phien set mau nau xam phong
hoa manh, ddi chd lin dat cd chieu day Idn Diem trugt
nay cd chieu day tang phii trung binh h = 3 m va gdc
ddc mat trugt binh quan p = 37°
- Diem trWcft km 16f + 900 thupc phu he tang Long
DailiOrSiid,
He tang nay phan bd tren tuyen dudng TL 11 va
doan tu km 40'+ 613 den 40'+ 959, tU km 42'+ 748
den 43' + 300, tU km 56' + 796 den 72' + 187, tU km
146'+ 591 den 148'+ 161, tUkm 149'+ 166 den 150' + 129, tu km 150'+ 789 den 167'+ 200 dudng HCM
va hoan toan vang mat tren tuyen dudng 12A, TL 10
Be day tang phii bien ddi tU 0,5 m den 4m; trung binh
tu 2 den 3 m vdi thanh phan chii ye'u la Idp set pha lan dam san mau nau xam, xam vang cd ngudn gdc tan tfch Tang dudi la da phien set mau nau xam phong hoa manh, ddi chd lan dat cd chieu day Idn Diem trugt nay cd chieu day tang phii trung binh h = 3 m va gdc ddc mat trugt binh quan p = 39°
Ket qua phan tfch chi tieu cd ly cac miu dat dac trung cho cac he tang va phu he tang ndi tren dugc trinh bay dbang 1
3 Kiem toan do on djnh trUcrt sUdn doc
De tien hanh kiem toan do dn djnh trugt cac sudn ddc chung tdi mudn de cap den mdt sd dieu kien tien quyet trong chgn sd dd, phuong phap kiem toan cung nhu lua chgn cac yeu td anh hudng va cac thdng sd dua vao cac cdng thUc tinh toan
Trudc het, ddi vdi tang phu dat loai set nam tren
da gdc nurt ne thdng thudng phat sinh trugt dat vdi mat trugt phang (gan nhu song song vdi mat sudn ddc), do
dd khdng the kiem toan dn djnh theo phuong phap mat trugt cung trdn nhu trong dat dfnh ddng nhat
Trong thdi gian mua keo dai, dat loai set tan tfch bj bao hoa gan nhu hoan toan Song do da gdc nirt ne va sudn ddc nen nude mua dd dang ngam xudng sau va hinh thanh tang chiira nude khe nirt ma khdng hinh thanh tang chira nude Id rdng de tao ap luc thu^y- ddng cung nhu ap luc thu^ tTnh de doa su dn djnh ciia tang phu dat loai set d phfa tren, tUc la trong kiem toan dn dinh trugt sudn ddc se khdng xet tdi tac ddng ciia ddng ngam nam sSu trong da nUt ne d phia dudi
Trong danh gia dn djnh trugt sudn ddc, ngoai cac yeu td hinh hgc dac trung ciia sudn ddc, chung tdi chu trgng nhieu hdn vai trd cua nude mua ngam sau trong viec lam giam luc dfnh ket, gdc ndi ma sat va gia tang khdi lugng the tfch dat
Phudng phap kiem toan dn djnh sudn ddc dugc tien hanh theo phuang phap mat trugt nam nghieng vdi "lang the dai dien"
y^„.h,.\.\.cosB.te(p, -i-c, l.l
Vdi ;;, = ^^^ ^-^^^ '• (1)
r,.ih \.\.sm/3
Ket qua kiem toan do dn djnh sudn ddc bj bien dang trugt ddi vdi cac khdi tai km 111 + 583, km 114 +
Trang 5KHAO SAT - THIET KE X A Y D U N G
251, km 121 + 163, km 127 + 000, km 134 + 040, km
930 + 500, km 46' +600, km 116' +600, km 121' +
800, km 162' + 900 dac trung va dai dien cho cac he
tang tuong irng: Rao Chan, Ban Giang, Bai Dinh, Muc
Bai, Bac Son thudc dudng 12A va Ddng Thg, phirc he Trudng Sdn, cac phu he tang Long Dai 3, Long Dai 2 v^ Long Dai 1 thugc dudng HCM dugc trinh bay tai bang 2
Bangl Gia tri trung binh ch! tieu ca ly c^c mau dat loai set pha thuoc c^c he tang
Cac chi
tieu
w,„
A
Ytn
Yc
G
n
e
Si-?
c,„
CPtn
w,,
Ybh
Cbh
tPbh
Cac chi
tieu
w,„
A
Yin
Yc
G
n
e
a,.;
c,„
(P,„
w,,
Yhh
Cbh
9 h h
Don vi tfnh
% g/cm' g/cm' g/cm^
%
% -cm^/kg T/m^
do
% g/cm^
Jim'
do Dan vi tfnh
% g/cm' g/cm' g/cm^
%
% -cm^/kg
Tim'
do
% g/cm^
Tim'
dd
Hg tang Rao Chan
20,69 2,70 1,92 1,59 80,15 41,11 0,697 0,026 3,49 20o52' 25,79 2,0 2,18
l e ^ i r
Ban Giang 17,65 2,69 1,91 1,62 71,83 39,78 0,661 0,024 3,0 22o10' 24,69 2,02 1,80 15°24'
Bai Dinh 17,56 2,69 1,92 1,63 72,67 39,39 0,650 0,025 3,1 23o18' 23,93 2,02 1,85 15'54'
Muc BSJ 21,66 2,69 1,94 1,59 83,47 41,09 0,698 0,032 2,84 20o07' 25,79 2,01 1,60 14°26'
Bac Son 20,02 2,69 1,98 1,58 76,71 41,26 0,702 0,023 3,05 22o29' 26,58 2,00 1,80
15 "44'
He tang Dong Tho
19,67 2,71 1,96 1,64 82,90 39,12 0,643 0,027 3,32
230 23,78 2,03 2,10 15° 20'
PhUc he Truong son 21,15 2,70 1,93 1,59 81,81 41,11 0,698 0,028 2,95
230 20' 25,79 2,00 1,90 15° 45'
Long Dai 3 20,61 2,71 1,95 1,62 82,99 40,22 0,673 0,029 3,26
220 45' 24,69 2,02 2,00 15° 50'
Long Dai 2 19,85 2,72 1,94 1,62 79,52 40,44 0,679 0,031 3,37
220 50' 24,69 2,02 2,10 16° 40'
Long Dai 1 19,23 2,73 1,97 1,65 80,15 39,56 0,655 0,030 3,56
230 12' 24,24 2,05 2,16 17° 10'
Bang 2 Tong hgp ket qua kiem toin do on dmh trugt suan ddc
Khoi trugt
Km 114+ 583
Km 117+ 251
Km 124+ 163
Km 129+ 489
Km 137+ 200
Km 517+ 812
Km 46T +600 Km116T+600
Km121T + 800
162T + 900
He tang Rao Chan Ban Giang Bai Dinh Muc Bai Bac San Dong Tho Trudng San Long Dai 3 Long Dai 2 Long Dai 1
Hg so dn dinh trugt ri Dieu kien tu nhien r|tn
1,47 1,49 1,39 1,46 1,47 1,45 1,46 1,41 1,52 1,49
Dieu kien bao hoS r|bh
0,96 0,94 0,86 0,94 0,95 0,92 0,93 0,89 0,97 0,94 Ket qua kiem toan cho thay trong dieu kien tu gay trugt nhd han tdng luc chdng trugt kha nhieu nhien 7, > 1, sudn ddc hoan toan dn dinh do tdng luc Ngugc lai, trong dieu kien bao hda nude //^ < 1, cd
Trang 6KHAO SAT - THIET KE X A Y DUNG
nghia la tdng luc gay trugt Idn hon tdng luc chdng trugt
nen phat sinh, phat trien trugt va thuc te da dien ra
diing nhu ket qua da kiem toan ndi tren
4 Hien trang va quy luat phan bo trUdt Id dat da
tren si/dn doc viing nghien cifU
De phuc vu du bao, phan vung nguy cd trugt Id dat
da tren sudn ddc vung nghien cUu, viec tdng hgp hien
trang va quy luat phan bd trugt Id cd y nghia quan
trgng
Tren co sd nghien cUu mdi quan he giUa sd diem
sut, trugt (ke ca ddng biin dat da) va cac yeu td tu
nhien va nhan tao rut ra hien trang va quy luat ph^n
bd sut, trugt dat da tren sudn ddc trong vung nghien
ciru nhu sau:
Bang 3 Ket quit thdng ke phan bd sd diem sut, trugt phan chia theo he tang
- Quy luat phSn bd sd diem sut, trugt theo dja tang
va thanh phan thach hgc da phong hoa:
Tren tuyen dudng thudc vung nghien ciru chii yeu gap cac da tram tich, da bien chat Ket qua dieu tra, khao sat cho thay, 193/197 diem trugt (chiem 97,97%) deu thugc cac he tang lien quan den da tram tfch, da bien chat, 04/197 diem trugt thudc phUc he Trudng Son lien quan den da Magma Cac da da bi phong hoa tao ra Idp phii phong hoa day hon va khdng ddng nhat, tao dieu kien cho nude mua d§ xSm nhap lam tam udt khdi dat, gay ra su bien ddi trang thai c§n bang Ung suat trgng luc va lam bien ddi tfnh chat cd ly dat da din den lam phat sinh, phat trien sut, trugt Theo he tang, sut, trugt dat da xay ra chii ye'u trong cac he tang Muc Bai, Ddng Thg va Bai Dinh (bang 3)
Dat e-dQ thuoc he tang Long Dai 1
Long Dai 2 Long Dai 3
He tang Rao Chan Tan Lam
He tang Ban Giang
He tang Muc Bai
He tang Ddng Thp Xom Nha
PhUc he Trudng San
La Khe
He tang Bac San
He tang Bai Dinh
Cong
So diem sut, trugt
10
16
6
7
04
13
28
35
01
4
21
14
38
197
Tl le % 5,08 8,12 3,05 3,55 2,03 6,60 14,21 17,77 0,50 2,03 10,66 7,11 19,29
100
- Quy luat phan bd sd diem sut, trugt theo do cao
tuyet ddi ciia dia hinh:
Theo do cao tuyet ddi cua dia hinh, khu vuc
nghien cUu cd the phan thanh 2 bac de xem xet va
danh gia mdi quan he do cao dja hinh vdi qua trinh
trugt, cu the nhu sau: Bac thir nhat < 200 m, sudn
thoai, cac dinh trdn Bac thir hai cao tU 200 m trd len,
sudn ddc cd do ddc cao hon, va khdi trugt, sut thudng
Idn hon Ket qua cu the dugc the hien d bang 4
Bang 4 Ket qua thdng ke phan bdsddiem sut,
truat theo do cao dia hinh
- Quy luat phan bd sd diem sut, trugt theo do cao
sudn ddc, mai ddc Theo do cao sudn ddc cd the phan thanh 2 bac de xem xet, danh gia anh hudng do cao sudn ddc ddi vdi trugt Id dat sau day: H < 10 m va H > 10 m Ket qua thdng ke dugc trinh bay tai bang 5
Bang 5 Ket qua thdng ke phan bd sd diem sut,
truat theo do cao suan ddc
06 cao (m)
<200
>200
Conq
So diem sut, truat
74
142
216
Tl le % 34,26 65,74
100
Dd cao (m)
<10
>10 Cgng
Sd diem sut, trugt
39
177
216
Tl le % 18,06 81,94
100
TU ket qua thdng ke trugt de dang nhan thay, cac
diem sut, trugt tap trung chii yeu d khu vuc cd do cao
tu 200 m trd len
- Quy luat phan bd sd diem sut, trugt theo be day tang phu tan sudn tfch:
Theo be day tang phii cung da phat hien mdi quan
he vdi qua trinh sut, trugt cua khu vuc nghien curu: cac qua trinh phong hoa anh hudng rat Idn den bien ddi tfnh chat cd ly cua dat da d sudn ddc Tuy theo mirc
Trang 7KHAO SAT - THIET KE XAY DUNG
do phong hoa ma tfnh chat ciia dat da: khdi lugng the
tich, do rdng, khe nirt, do ben, do hap thu nude bj bidn
ddi Khi bi phong hoa da cUng bien th^nh da nira
cdng, tiep tuc bj phong hoa se trd thanh dat xdp, dat
loai set mem dfnh Mure do gay trugt Id phu thudc vao
tfnh chat ciia dat da cau tao nen tang phu nay
Be day tang phii tren tuyen dudng khu vuc nghien
cUu bien ddi tU dudi 1 m den 10 m 6 cac dinh niii,
chieu day vd phong hoa chi xap xi 2 m, d giOa sudn
nui tu 3 den 7 m, d chan niii cd the dat den 5 -10 m
De xem xet quan he giira quy luat phan bd sd diem
sut, trugt vdi be day vd phong hoa, sd diem sut, trugt
Ung vdi cac be day: < 2 m, 2 -10 m va > 10 m da dugc
thdng ke va md ta d bang 6
Bang 6 Quan he giUa phan bd diem sut,
trugt vdi be day tang phu
Bang 7 Ket qua thdng ke phan bd ciic diem sut,
trugt theo dd ddc dia hinh
Be day (m)
<2
2-10
10-20
Cong
So diem sut, trugt
46
151
0
197
Ty- le % 23,35 76,65 00,00
100
TU bang 6 de dang nhan thay sut, trugt xay ra
nhieu nhat d nhOng nai cd be day tang phii tU 2 m den
10 m
- Quy luat phan bd cac diem sut, trugt theo do ddc
dja hinh (sudn ddc)
Trong trugt theo mat trugt nam nghieng, thdng
thudng gdc mat trugt tuong duang vdi gdc sudn ddc
(dg dd'c dja hinh)
Chung tdi da sir dung thang do dd'c sudn ddc:
<20°, 20°- 35°, 35°- 65° va > 65° de danh gia va nghien
cUu quy luat phan bd cac diem sut, trugt theo do dd'c
dia hinh Ket qua thdng ke dugc trinh bay d bang 7
Dd ddc (m)
<20°
20°-35°
35°-65°
>65°
Cong
Sd didm sut, truat
0
61
136
0
197
T916 % 00,00 30,96 69,04 00,00
100
Nhu vay, cac diem sut, trugt tren tuyen dudng vung nghien ciru tap trung nhieu nhat va chu yeu vao cac sudn cd do ddc tU 35° den 65°
TU sd lieu dieu tra khao sat gdc ddc dja hinh (tuong dUdng gdc nghieng mat trugt) cd the lap bang quan he cudng do, quy md trugt dat da vdi gdc ddc dia hinh (bang 8); quan he cudng do, quy md sut dat da vdi gdc ddc dja hinh (bang 9) va quan he cudng dd, quy md ddng bun dat da vdi gdc ddc dja hinh (bang 10)
Bang 8 Anh huang trugt dat da theo gdc ddc dia hinh
Goc nghieng suon ddc a
<20°
20°- 35°
35° - 65°
>65°
Anh hudng truat dat da Cudng do
Rat it xay ra VUa - Manh Manh - Rat manh Rat it xay ra
Quy md Rat ft xay ra Rat Idn - Ldn Ldn - Trung binh - Be Rat ft xay ra
Bang 9 Anh huang sut dat da theo gdc ddc dia hinh
Goc nghieng sudn doc a
<20°
20° - 35°
35° - 65°
>65°
Anh hudng sut dat da Cudng dd
Rat ft xay ra VUa Manh Rat manh
Quy md Rat ft xay ra Rat be
Be - Trung binh Ldn
Bang 10 Anh huang ddng bun dat da theo goc ddc dia hinh
Goc nghieng sudn dd'c a
<20°
20° - 35°
35° - 65°
> 6 5 °
Anh hudng dong bun dat da Cudng do
Rat it xay ra VUa - Manh Manh - Rat manh Rat it xay ra
Quy md Rat ft xay ra Ldn - Trung binh Trung binh - Be - Rat be Rat ft xay ra
NhCi-ng khu vuc cd do ddc dia hinh tU 0 - 20° la
nhung be mat thoai hoac gan nhu nam ngang (be mat
bdc mdn hoac tfch tu), nen khdng hoac rat ft xay ra
hien tugng sut, trugt dat da
Nhung khu vuc co do ddc dja hinh Idn hon 65° rat
dd'c, be day tang phu mdng hoac rat mdng nen rat ft
xay ra trugt va ddng bun dat da; thudng xay ra sut dat
da, sut da va dd da
- Quy luat phan bd sd diem sut, trugt theo quy md khdi dich chuyen:
Can cir vao quy md khdi dich chuyen, sd cac diem sut, trugt dugc phan bd theo bang 11
Trang 8KHAO SAT - THIET KE XAY D U N G
Bang 11 Kef qua thdng ke phan bd c&c diem sut, trugt theo quy md khdi dich chuyen
Quy mo khoi dich chuyen
Be va rat be ( < 1 0 W ) Trung binh (10"-lO^m^
Ldn(10^-10°m^
Rat Idn (10°-10'm^
Cucldn(10'-10"mM Cong
Sd diem dich chuyen
175
17
05
00
00
197
Ty le % 88,83 08.63 02,54 00,00 00,00
100
- Theo loai hinh sudn ddc tu nhien (d each xa dudng giao thdng) va sudn ddc khdng tu nhien (bao gdm mai ddc va sudn ddc gan ke dudng giao thdng), phan bd cac diem sut, trugt dugc md ta tai bang 12
Bang 12 Phan bd cac diem trugt, sut va dong bun theo loai hinh suan ddc
STT
1
2
Loai hinh sudn doc
Tu nhien Khdng tu nhien Cong
Sd diem dich chuyen
03
194
197
Ty le % 01,52 98,48
100
- Quy luat phan bd cac diem sut, trugt theo loai hinh djch chuyen:
Theo loai hinh djch chuyen, cac diem sut, trugt dugc ph§n bd theo bang 13 (khdng tfnh loai hinh sut da va dd da) hoac theo bang 14 (khi tfnh ca loai hinh sut da va dd da)
Bang 13 Kef qua thdng ke phan bd cac diem sut, trugt
theo loai hinh dich chuyen (khong tinh loai hinh sut da va do da)
STT
3
4
5
Loai hinh dich chuyen Trucft dat da Sut dat da Ddng bun dat da Cong
Sd diem dich chuyen
18
168
11
197
Ty 16 % 9,14 82,28 8,58
Bang 14 Kef qua thdng ke phan bd cic diem sut, trugt theo
loai hinh dich chuyen (tinh ca loai hinh sut da va dd di)
STT
1
2
3
4
5
Loai hinh dich chuyen
Dd da
Sut da Truat dat da Sut dat da Ddng biin dat da Cong
Sd diem dich chuyen
03
16
18
168
11
216
Ty 16 % 1,39 7,41 8,33 77,78 5,09
5 Ket luan
Tren cd sd ket qua nghien cUu, kiem toan va danh
gia do dn dinh sudn ddc dudng giao thdng viing mien
nui tinh Quang Binh, cd the rut ra mdt sd ket luan nhu
sau:
- Qua trinh sut, trugt dat da tren sudn dd'c, mai dd'c
cac tuyen dudng giao thdng vung mien niii tinh Quang
Binh chii yeu phat sinh, phat then tren cac sudn ddc,
mai ddc khdng tu nhien da chju su tac ddng ciia cac
hoat ddng kinh te, xay dung, cdng trinh va ddt pha
rUng lam nudng riy ciia con ngudi, chiem 98,48%
tdng sd diem dich chuyen dugc khao sat, nghien cUu;
- Theo loai hinh, djch chuyen trgng luc dat da khu
vuc nghien ciru chiem phd bien nhat la sut dat da
(chiem 82,28 %), trugt dat da (chiem 9,14%), cdn lai la ddng bun dat da chiem 8,58% tdng sd cac diem djch
chuyen Neu tfnh ca sut da va dd da thi [^ le nay la: dd
da (1,39 %), sut da (7,41%), trugt dat da (8,83%), sut dat da (77,78%) va ddng bun dat da (5,09%) tdng sd cac diem djch chuyen;
- Trong vung nghien curu, sut, trugt xay ra nhieu nhat trong he tang Muc Bai (chiem 14,52%), Ddng Thg (chiem 18,99%) va Bai Dinh (chiem 20,67% tdng sd diem sut, trugt), it nhat cd he tang Xdm Nha, TSn LSm
va phurc he Trudng Son Be day tang phii vd phong hoa cua cac khdi sut, trugt dao dgng chii yeu tU 2 den
10 m (chiem 76,65%) Cac diem sut, trugt phat sinh, phat trien nhieu nhat d do cao tuyet ddi dia hinh tren
Trang 9KHAO SAT - THIET KE XAY DUNG
200 m (chiem 65,74%) Phan Idn cac diem sut, trugt
CO do cao sudn ddc tu nhien tir 10 m trd len (chiem
81,94%) va do ddc dja hinh (gdc sudn ddc tu nhien)
35° - 65° (chiem 69,04%) Cac khdi sut, trugt cd quy
md chii yeu la be va rat be (nhd hon 10" m^) va chiem
88,83% tdng sd diem sut, trugt; khdng cd loai quy md
ratldn(10^-10°m^)
Cac khdi trugt be va rat be xay ra d khu vuc cd
gdc dd'c mat trugt cao 30° - 45° hoac > 45°; Cac khdi
trugt trung binh va Idn xay ra d khu vuc cd gdc dd'c
mat trugt be va vUa tU 20° - 30° Cac khdi sut deu cd
quy md be va rat be, thudng phat sinh, phat trien chu
yeu tren cac sudn ddc, mai ddc cd gdc dd'c > 45° Cac
khdi ddng biin dat da cd quy md rat be va xay ra chii
yeu tren cac sudn dd'c bac thang va sudn ddc cd gdc
ddc tu 35° - 45°; dac biet do dja hinh chung ciia ca
vung rUng nui Trudng Sdn ddc nen tren khu vuc
nghien cUu, ddng bun da xay ra cung rat ft Do da va
sut da vdi quy md rat be va tan suat xay ra cung rat ft
Hien tugng trugt da chua phat hien d khu vuc nghien
ciru
- Sut, trugt dat da thudng phat trien manh d khu
vuc ddi niii, nhat la cac deo cao, dja hinh phan cat
phUc tap, hoat dgng xam thuc bdc mdn manh me, nai
Id da gdc d§ bj phong hoa, pha Uu^ do cac tac ddng
ngoai sinh, tich tu tan tfch, sudn tfch day, da va dang
phat sinh nhieu khdi trugt Id cd va hien dai Trugt
thudng xay ra trong tang dat set pha, set va chu yeu la
trugt theo mat phang nam nghieng ciia Idp da gdc
hoac theo ddi yeu gan ke cam thuan xudng dudng
giao thdng
Qua ket qua khao sat, nghien curu va kiem toan, cd
the khang dinh: nhOng khu vuc cd gdc ddc mat trugt
nam nghieng dudi 20° la nhung be mat thoai hoac gan
nhu nam ngang (be mat bdc mdn hoac tfch tu) nen
khdng hoac rat ft xay ra hien tugng sut, trugt dat da
Nhung khu vuc cd gdc ddc dja hinh Idn han 65° vdi be
day tang phii mdng hoac rat mdng cung rat ft xay ra
trugt; thugng xay ra dd da, sut da va mdt phan ft sut
dat da
- Nguyen nhan kjch phat quan trgng nhat lam phat
sinh, phat trien sut, trugt dat da tren sudn ddc vung
nghien cdu la tac dgng ciia mua vdi cudng do Idn va
keo dai Thuc te khao sat, nghien ciru cho thay: sut,
trugt dat da hau nhu chi xay ra d at vao miia mua lu
vdi cudng dd va lugng mua Idn, keo d^i tU 2 - 4 ngay lien tuc, cdn vao mua khd hiem khi xay ra
- Kiem toan do dn dinh cOa sudn ddc, mai ddc can sir dung gia trj cac dac tfnh dia chat cdng trinh trong mua bat Igi nhat - mua mua 10, tUc la trong dieu kidn dat da bj bao hoa nude
- Ddi vdi viing nui cao nhu khu vuc nghidn ciru, phuong phap kiem toan dn djnh theo mat trugt nam nghieng la phu hgp va dung vdi thuc trang dieu kien dja chat cdng trinh khu vuc
TAi Ll£U THAM KHAO
1 Bao cao ket qua khao sat dia chat cdng trinh - Du an nang cap cai tao qudc Id 12A doan Khe Ve - ChaLo
Cdng ty cd phan tu van xay dung giao thong 533, Da Ning, 2006
2 Bao cao tdng quan dja chat va tai nguyen khoang san
tinh Quang Binh Cue Dia chat va Khoing san Viet
Nam, Hi Noi, 2001
3 LOMTADZE V.O Dja chat cdng trinh - Dia chat dong
luc cdng trinh, NXB Dai hoc vi trung hoc chuyen
nghiep Hi Noi, 1982
4 Bao cao thiet hai bao, lut nam 2005 Sd Giao thong Van
tai Quang Binh, Quang Binh, 2005
5 Bao cao thiet hai bao, lut nam 2006 Sd Giao thong Van
tai Quang Binh, Quang Binh, 2006
6 Bao cao ket qua de tai Dieu tra nghien cUu tong hgp Dia chat va Khoang san phuc vu quy hoach phat trien
kinh te va bao ve mdi trudng tinh Quang Binh Trudng
Dai hoc Mo Dia chat, Ha Noi, 2004
7 Bao cao tai bien dja chat sut Id taluy duang, am, lu
quet d Viet Nam - Hien trang, nguyen nhan, du bao va
mot so giai phap phdng tranh giam thieu hau qua Vien
nghien cUu Dia chat vi Khoing san Hi Noi, 2005
8 E M E J l b i l H O B A E n OcHOBHbie
aaKOHOMcpHOCTH onojisHCBbix npoueccoB usd
Hedpa-MocKea, 1972
9 MACJIOB H.H ycjlOSHJI yCTOHHHBOCTH CKJIOHOB
H OTKOCOB B r H / i p 0 3 H e p r e T H M e C K 0 M
CTponTe.nbCTBe rocsHepeousdam, 1955
Ngay nhan bai: 7/7/2010