NGHIEN CLTU MOT SO YEU TO ANH HUONG TOI TOG Op KHAI THAC TREN TUYEN QUOC LO 1A
DOAN TLT OA N A N G Ol QUANG NGAI
: ,1 tv i t y i ; TS. VO HOAI NAM, ThS. DO DUY DINH
ThS. B6 TRONG AN, ThS. PHAM HONG QUANG Khoa Xay dung Cau dudng - Trudng Dai hge Xay dtrng
Tom t i t : Bai bao trinh bay ket qua nghien cffu anh hudng cua mot so yeu to den toe do khai thac tren tuyen Quoc id IA doan tff Da Nang di Quang Ngai. Thong qua viec xay dffng cac phuang trinh hoi quy thuc nghiem va phan tfch ket qua khao sat, nghien cffu cho thay do bang phang cua mat dudng, khoang each tTnh khong ngang, ban kfnh dudng cong nam va suat thay doi goc ngoat dudng cong la nhffng nhan td co anh hffdng dang ke den tdc do khai thac tren doan tuyen nghien cffu.
Summary: This paper presents the results of examining some influencing factors to the oper- ating speed on National Highway IA, Danang - Quangngai section. Basing on the regression methods, the authors did revealed that IRI (International Roughness index), lateral clearance, horizontal radius and curvature change rate are significant factors effecting to the operating speed of the aforementioned road section.
1. MO DAU
Tde do khai thac (Vss) la tde do ma tai dd cac lai xe chgn de van hanh trong dieu kien ddng ttr do (AASHTO, 2001 [13]) va thtrdng dugc xac djnh bang gia trj tdc do dng vdi tan suat 85% cija bieu do tan suat tfch luy do dugc tren mdt doan dudng cu the. Do y nghTa la mdt chi tieu ca ban trong viec danh gia chat lugng khai thac cua dudng, tde do khai thac va cac van de cd lien quan de'n tdc do khai thac da dugc nghien cdu hon 55 nam d nhieu qud'c gia, tuy vay d Viet Nam hau nhu ehua cd mdt ket qua nghien cdu nao ve van de nay, dae biet hau nhu ehua ed cac nghien cdu khao sat danh gia tac ddng cua eac ye'u td anh hudng de'n tdc do khai thac trong dieu kien dudng va mdi trudng d Viet Nam.
Tdc do xe chay chju anh hudng phde tap bdi nhieu yeu td nhu: dieu kien dudng, mdi trudng, to ehdc giao thdng va ngtrdi lai. Mdc do anh hudng
cua cae yeu td cung rat khac nhau ddi vdi tdng doan dudng eu the. De cd co sd nang cao duge tde do xe chay cung nhu de xuat tde do xe ehay hgp ly eho tdng doan dudng, rat can cd nhdng nghien cdu khao sat danh gia quan he gida tdc do khai thac va cac yeu td anh hudng. Bai bao trinh bay ket qua nghien cdu anh hudng eua mdt sd yeu td den tdc do khai thac tren doan tuyen qudc Id I A doan td Da Nang di Quang Ngai.
Trong nghien cdu nay nhdm tac gia tap trung nghien cdu anh hudng eija do bang phang eua mat dudng, khoang each tmh khdng ngang, ban kinh dudng cong nam va suat thay ddi do eong (curvature change rate) den tde do khai thac tren doan tuyen nghien cdu.
2. KHAO SAT VA THU THAR SO LIEU
Nhu da de cap trong bai bao "Khao sat danh gia tdc do khai thac tren tuyen qudc Id I A doan t d D a Nang di Quang Ngai - Tap chf Cau dudng
TAP CHl CAU OadNG VIET NAM
KHOA HOC - CONG NGHE
SO 03/2010", doan tuye'n nghien cdu thudc Qudc Id 1A doan td Da Nang di Quang Ngai vdi chieu dai tuyen khoang 103km (td ly trinh Km942 den Km1045). Quy md dudng cap III ddng bang, tdc do thie't ke 80 km/h. Cau tao mat cat ngang vdi be rgng nen dudng 12.0 m bao gdm: chieu rdng phan xe ehay 2 x 3.5 = 7.0m, le gia ed (lan xe thd so) 2 X 2.0 = 4.0m, le dat 2 x 0.5 = 1.0m. Rieng doan td Km 1036 den Km 1037 be rdng nen dudng 20.0m, phan xe ehay gdm 4 lan xe 4 x 3.5
= 14.0m. Toan bd chieu dai tuyen ed do ddc dgc
< 3%, cac ban kfnh dudng eong nam > 250m.
Toan bd ehieu dai doan tuyen duge phan thanh 66 phan doan, trong dd tien hanh khao sat tde do tai 57 doan (mdt sd doan trong khu dan eu, thj tran cd cam bien han che tdc do khdng tien hanh khao sat). Phuong phap khao sat tdc do xe chay dugc sd dung la phuang phap ddng hd bam giay. Thdi gian tien hanh khao sat td ngay 18/11/2009 den ngay 26/11/2009 trong dieu kien thdi tiet tdt.
Ngoai viec khao sat tdc do xe chay, duge str giup da cua Ban QLDA dudng bd 5, Ban QLDA dudng bd 2, Khu QLDA dudng bd 5, Trung tam ky thuat dudng bd 5, Cdng ty Co phan Quan ly va Xay dung Quang Nam - Da Nang, Cdng ty Co phan Quan ly va Xay dung Quang Ngai, Cdng ty Co phan Tu van XDGT Nghe An va Cdng ty Co phan Tu van XDCT Giao thdng Trudng Djnh, cae so lieu sau cung da dugc dieu tra, thu thap:
- Sd lieu ve dac trung hinh hgc tuyen dudng:
binh dd, mat cat dgc, mat eat ngang.
- Sd lieu ve tinh trang mat dudng: do bang phlng (tri sd do ghd ghe qudc te IRI), do nham, ke't cau mat dudng, le dudng v.v..
- Sd lieu ve cae cdng trinh dgc tuyen nhu trudng hge, khu dan cu, chg bua v.v..
- Sd lieu ve td ehdc giao thdng, cdng trinh dam bao an toan giao thdng dgc tuyen: cgc tieu, bien bao, tudng hg lan, son ke vach v.v..
^ - Sd lieu ve tai nan giao thdng dgc tuyen, bao gdm: so lugng, ly trinh xay ra tai nan, thdi diem tai nan.
Dac biet, td cac so lieu ve cac cdng trinh dgc tuyen, nhdm tac gia da khao sat do dac khoang each tTnh khdng ngang, dugc djnh nghTa ia khoang each ngang td mep le dudng den vj trf cdng trinh xay dtrng hai ben dudng. TTnh khdng ngang dugc xem la yeu td the hien anh hudng cua khu dan ctr hai ben dudng den tdc do khai thac, mdt yeu td cd anh hudng Idn den giao thong tren nhieu tuyen qudc Id d Viet Nam hien nay.
Mdt sd ket qua khao sat, thu thap sd lieu dugc the hien trong Bang 1.
3. NGHIEN CIJU ANH HU'dNG CUA MOT SO YEU TO DEN TOC DO KHAI THAC
3.1. Dp bing phdng
Theo thdng ke t d Bang 1 cho thay, doan tuyen nghien cdu cd 12 phan doan vdi chieu dai 25673m (chiem 24.82% chieu dai doan tuyen nghien cdu) ed do bang phang cua mat dudng tdt, 45 doan vdi chieu dai 64899m (62.74%) co do bang phang trung binh, 9 doan cdn lai co ehieu dai 12866m (12.44%) mat dudng cd do bang phang kem can cai thien.
Sau khi loai bd cac doan bj han che tdc do theo bien bao (V < 50km/h) ngoai hien trudng, mdi quan hd gida do bang phang IRI va tdc do Vgs dugc the hien tren Hinh 1. Vv
Xet anh hudng ctia do bang phang IRI ddi vdi
tdcddVss eho thay: • - Trudng hgp IRI > 4 (do bang phang xau ddi
vdi dudng cao tdc cd tdc do 80km/h, [5]): cac cdng thdc thtrc nghiem the hien mdi quan he gida hai bien deu cd he sd tuang quan xap xi nhau va quan he tuyen tinh dugc the hien d cdng thdc (3.1), dieu nay cung cho thay khi IRR tang len thi tdc do khai thac cd xu hudng giam do than xe bj rung manh ndn phai giam tde do.
TAP CHI CAU DLTONG VIET NAM
Bang 1: Tong hop ket qua khao sat toe do khai thac va cac yeu to anh huong
D o g n
(1)
1 2 3 4 5 6 7 S 9 10 11 12 13 14 15 16 17 18 19 2 0 21 2 2 23 2 4 25 26 2 7 2 8 29 3 0 31 3 2 33 3 4 35 36 3 7 3 8 39 4 0 41 4 2 4 3 4 4 4 5 46 4 7 4 8 49 5 0 51 52 5 3 5 4 55 56 5 7 5 8 5 9 6 0 61 6 2 6 3 6 4 6 5 6 6
Ly trinh
(2) 9 4 2 + 0 0 0 9 4 3 + 1 5 0 9 4 4 + 3 0 0 9 4 5 + 5 0 0 9 4 7 + 0 0 0 9 5 5 + 0 0 0 9 5 6 + 5 2 0 9 5 7 + 1 0 0 9 5 8 + 3 0 0 9 5 8 + 6 0 0 9 5 9 + 2 0 0 9 6 0 + 0 5 0 9 6 1 + 4 2 0 9 6 2 + 8 0 0
9 6 3 + 8 7 0 9 6 4 + 9 5 0 9 6 6 + 5 0 0 9 6 8 + 7 0 0 9 6 9 + 4 0 0 9 7 0 + 3 3 0 9 7 1 + 0 0 0 9 7 3 + 1 3 0 9 7 3 + 7 0 0 9 7 4 + 9 5 0 9 7 7 + 6 0 0 9 7 8 + 2 0 0 9 7 9 + 2 0 0 9 8 0 + 0 0 0 9 8 2 + 0 0 0 9 8 3 + 0 5 0 9 8 3 + 6 5 0 9 8 8 + 9 0 0 9 9 0 + 4 2 0 9 9 6 + 7 0 0 9 9 7 + 8 0 0 9 9 9 + 5 0 0 1 0 0 0 + 1 5 0 1 0 0 0 + 7 5 0 1 0 0 2 + 0 0 0 1004+240 1 0 0 6 + 3 0 0 1 0 0 7 + 5 0 0 1 0 0 9 + 3 0 0 1010+100 1 0 1 1 + 3 9 0 1 0 1 3 + 7 0 0 1 0 1 4 + 6 0 0 1020+200 1021+000 1022+200 1 0 2 5 + 6 0 0 1 0 2 7 + 0 0 0 1 0 2 8 + 8 0 0 1 0 3 1 + 0 0 0 1 0 3 2 + 2 0 0 1 0 3 3 + 0 0 0 1033+700 1 0 3 4 + 3 5 0 1035+600 1037+370 1 0 3 9 + 2 6 0 1 0 4 0 + 0 0 0 1 0 4 2 + 2 0 0 1 0 4 2 + 8 0 0 1 0 4 3 + 6 2 0 1 0 4 4 + 1 5 0 1 0 4 5 + 0 0 0
Chieu
( m ) (3)
1 1 3 5 1 2 7 5 1200 1 5 0 0 8 0 0 0 1 4 9 4 7 1 2 1 1 9 0 3 0 0 5 2 8 8 8 7 1363 1 3 8 0 1 0 7 0 1 0 8 0 1 4 0 8 2 1 9 0 7 0 0 9 7 0 6 4 9 2131 5 7 0 1 1 7 6 2 7 7 2 5 7 3 1 3 3 8
8 0 9 1 9 6 9
9 9 2 6 0 0 5 2 3 7 1507 6 2 8 0 1 1 0 0 1 7 2 5 6 0 3 6 0 0 1 1 0 0 2 4 7 2 2 0 7 6 1 1 8 9 1 7 7 5 7 9 9 1324 2 1 8 9 10CU 5 5 9 101 ^ 124'.
3 6 4 4 1 2 1 3 1 4 8 5 2 1 5 8 1 1 5 5 8 1 2 7 Q O 6 5 0 1 2 5 0 1 8 9 9 1 9 6 3 1
7 2 6 2 2 3 5
6 0 0 8 0 3 4 5 9 8 9 6
Dja v$t 2 b§n
(4)
^^^^^H
n h a dart+ruOn8 '•
nj^ng '
n h A d S n + ru<;ng ruOne s nhd a&n + nH^ng
%f%xrm'mBSmB^
n h d d d n 4- rti^g
ruOng *
ru«ng "• ''
ruC>ns
nhd d a n + nidns
Kj? Xt ru*ns„ . ,' '..;,J nhA dan + m^OQ
n h 6 d i n + nH>ng
nhfi d&n + ruOng
^ ^ ^ ^ J h A d a n + n j ^ g
^ ^ j i U i d i n ••- r u ^ g
n h & d S n *• rti^g
J rij^nn n h d d a n ••- ruOng
""" nh* dan + rvOttg _,
^ ^ ^ ^ ^ b k d a n + ru^ng
^ ^ ^ B ^ A d a n + ni^ng
nhA d4n + ru^g n h A d a n ~+ ru^ng
nha dAn + m«na
n h * d d n * nj^ng
(km/h) (5)
4 6 6 0 51 69 8 5 4 9 7 4
6 8 5 9 6 7 7 6 73
- -
5 0 7 7
-
69.5 81 58.5
8 7 6 2 7 8 48.5 73.5 7 2 7 8
-
7 9 4 3 6 5
-
53.5 5 9 51.5
7 3 5 4 6 9 7 2
-
71.5 6 0 7 6 5 8 4 5 6 9 7 6 7 8 7 5 5 9 71 SO 5 4 71 7 0 6 0
-
7 3 71 7 0 4 9 8 2 71 7 9
(km/h) (6)
8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 SO SO 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0
Vblin b6o (km/h) (7)
8 0 8 0 8 0 8 0 8 0 5 0 8 0 4 0 8 0 8 0 8 0 8 0 8 0 8 0 4 0 8 0 8 0 8 0 5 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 4 0 5 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 8 0 4 0 8 0 4 0 8 0 SO 4 0 SO 8 0 8 0 SO SO SO 5 0 8 0 8 0 SO 8 0 5 0 8 0 8 0 8 0 SO 8 0 SO SO
LL^U \Ktiyng
(xe/ngd) (8)
5 2 2 8 5 2 2 8 5 2 2 8 5 2 2 8 5 2 2 S 5 2 2 8 5 2 2 8 5 2 2 8 5 2 2 8 5 2 2 8 5 2 2 8 5 2 2 8 5 2 2 8 5 2 2 8 5 2 2 8 5 2 2 8 5 2 2 8 5 2 2 8 5 2 2 8 5 2 2 8 5 2 2 8 5 2 2 8 5 2 2 8 5 2 2 S 5 2 2 8 5 2 2 8 5 2 2 8 5 2 2 8 5 2 2 8 5 2 2 8 5 2 2 8 5 2 2 8 5 2 2 8 3 4 2 8 3 4 2 8 3 4 2 8 3 4 2 8 3 4 2 8 3 4 2 8 3 4 2 8 3 4 2 8 3 4 2 8 3 4 2 8 3 4 2 8 3 4 2 8 3 4 2 8 3 4 2 8 3 3 6 3 3 3 6 3 3 3 6 3 3 3 6 3 3 3 6 3 3 3 6 3 3 3 6 3 3 3 6 3 3 3 6 3 3 3 6 3 3 3 6 3 3 3 6 3 3 3 6 3 3 3 6 3 3 3 6 3 3 3 6 3 3 3 6 3 3 3 6 3 3 3 6 3
ITnh khong n g a n g
( m ) (9)
5.8 9.2 3.8 12.7
-
6.6
- - -
7.3 11.8
-
4.7
-
5.2 7.7 18.3 12.2
- - -
7.8
-
9.4
-
4.8
-
12.2
-
5.3
- - - -
7.6 7.8 8.7 8.2 6.4 12.6
-
3.3 9.8 4.7 14.5 8.2 3.1 5.5
-
11.5 12.5 7.5
-
2.8
-
8.6
-
3.7 2.8
-
6.7 4.5 2.9 5.7 7.1 3.6
IRI (m/km)
(10)
2.3 2.3 2.3 2.7 2.5 3.2 2.6 2.6 2.5 2.5 2.7 2.0 2.8 4.4 2.1 2.0 2.0 2.9 3.2 2.0 4.2 4.9 2.3 2.3 2.6 2.5 2.7 2.4 2.3 2.4 2.5 2.5 2.9 2.3 1.9 2.5 2.5 2.3 2.2 2.2 3.2 3.5 3.1 2.5 2.2 3.6 3.4 3.2 2.9 4.8 2.6 2.9 5.0 5.1 4.9 3.4 3.5 3.7 2.9 2.2 4.5 2.6 4.1 3.9 2.7 2.1
n h d m ( m m )
(11)
0.08 0.06 0.08 0.19 0.43 0.18 0.13 0.09 0.09 0.10 0.11 0.07 0.19 0.18 0.32 0.35 0.36 0.28 0.30 0.25 0.20 0.S9 0.17 0.17 0.23 0.27 0.31 0.32 0.38 0.19 0.35 0.42 0.42 0.51 0.66 0.36 0.36 0.31 0.33 0.33 0.32 0.42 0.22 0.33 0.37 0.44 0.43 0.34 0.3 0.9 0.4 0.37 0.57 0.9 0.38 0.4 0.39 0.52 0.33 0.28 0.44 0.58 0.75 0.44 0.44 0.29
TAP CHi CAU DUONG VIET NAM
KHOA HOC - CONG NGHE
V85 =-15.88 IRI+ 145.1 r^ = 0.437 (3.1)
1 60
• » ^
•'CV-^.
• • • • $ • ^ • • ••
2 3 4 IF) (m/km)
Hinh 1. Quan he giffa toe do Vgg va IRI - Trudng hgp IRI < 4 (do bang phang tdt, [5]):
do mat dudng cd do bang phang tdt, cac xe gan nhu khdng chju anh hudng cua IRI khi chuyen ddng. Mdi tuong quan gida hai bien VQ^ va IRI trong trudng hgp nay la rat ye'u:
Vgs = -4.656 IRI + 84.69 r= = 0.104 (3.2)
Hinh 2. Quan he giffa toe do Vgs va IRI l<hi IRI > 4 3.2. Tfnh l(hdng ngang
De xem xet str anh hudng ctia tTnh khdng ngang de'n td'c do khai thac, cae doan bj han che td'c do theo bien bao V < 50km/h bj loai bd. Ket qua the hien tren bieu do Hinh 4 cho thay: dd'i vdi eae doan ed khoang tTnh khdng ngang nhd hon 10m thi cd 2 day td'c do khai thac: (1) qua cae thi tran, khu dan cu ddng due Vss nam trong khoang 46 - 60 km/h; (2) qua cac khu vtrc dan cu sdng rai rac, thua thdt Vgs cd gia trj trong khoang 69 - 81 km/h, dae biet tap trung trong khoang 70 - 73
km/h. Ddi vdi cac doan cd tTnh khdng ngang td 10m trd len, td'c do khai thac hau het trong khoang 70km/h - 78 km/h.
Hinh 3. Quan he giffa toe do
VQS va IRI khi IRI = 4
Do tTnh khdng ngang cua cac phan doan tuyen di qua cac khu dan cu thua thdt va cac doan dat trdng gan nhu khdng anh hudng de'n td'c do khai thac nen chi xet mdi quan he tuang quan gida hai bie'n khi di qua khu dan cu. Mdi quan he nay dugc the hien qua mdt sd cdng thdc hdi quy thtrc nghiem sau:
- Cdng thdc (3.3) the hien quan he tuye'n tfnh:
Vgg = 1.6842 L + 42.458 f = 0.423 (3.3) - Cdng thdc (3.4) the hien quan he phi tuye'n:
Vg5 = 1.5526 L2-19.861 L + 1 1 4 . 1 5
r= = 0.539 (3.4) Trong dd: L la tTnh khdng ngang (m).
5 10 15 Khoing llnh k M n g ngang (m)
Hinh 4. Quan he giffa tde do VQQ va tTnh khong ngang
Ti?LP CHI CAU DU'ONG VIET NAM
Cac quan he thtrc nghiem 3.3 va 3.4 cho thay tTnh khdng ngang la ye'u td cd anh hudng dang ke de'n td'c do khai thac dudng. Td dd cho thay rat can thtrc thi cac bien phap dam bao han che anh hudng cua khu dan ctr sinh sdng dgc hai ben dudng trong dd cd viec quy djnh khoang each tTnh khdng ngang tdi thieu dam bao an toan xe chay va nang cao td'c do khai thac dudng trong cac doan tuye'n di qua cac khu dan cu cd mat do xay dtrng tuang dd'i Idn.
3.3. Duang cong nam
Dd'i vdi cac doan tuye'n nam trong dtrdng cong quan he thtrc nghiem gida td'c do khai thac va cac yeu td anh hudng nhtr: ban kfnh, do cong eua dudng cong, mdc do thay ddi gdc ngoat cua dudng cong, sieu cao, he sd ma sat ngang gida mat dudng va ldp xe v.v.. da dugc de cap de'n trong nhieu nghien cdu d ntrdc ngoai. Trong cac yeu td anh hudng dd, mdc do thay ddi (hay suat thay ddi) gdc ngoat dtrdng cong CCR (curvature change rate) dugc nhieu nghien cdu xem la dai lugng anh hudng trtrc tiep de'n qua trinh thay ddi td'c do khai thac. Ve mat djnh tfnh, trj sd suat bie'n ddi gdc ngoat dudng cong CCR cang nhd thi td'c do khai thac cang tang va cang nang cao dugc td'c do xe chay. Ngugc lai, dudng eong cd trj sd suat thay ddi gdc ngoat cang Idn thi kha nang mat an toan xe chay cang tang len [15]. He sd suat thay doi gdc ngoat dtrdng cong CCR la thdng sd thie't ke dugc dua ra d CHLB Ddc [16].
s o ; I— 50 I
! l '
!<£. 40 l § 30 • I I
20 '•
0 ^
4
2 4 6 Jthoing ISih khing ngang (TO)
Hinh 5. Quan h& giffa toe do Vgg va tinh khong ngang doan qua khu dan eu
Trudng hgp dan gian, ddi vdi dtrdng cong trdn cd ban kfnh R va chieu dai dudng cong K , trj sd CCR dtrac xac dinh nhtr sau:
,410^ ^ . a x i o '
CCR -.^ -^
K K
K . K
, gofl/lan (3.5)
a- goc ngoat D! = —,rsd= — 61,],^ou (400goa^=2ir3d) R R
Theo [26], tieu chf danh gia nhu sau:
- Dd'i vdi cac dtrdng cong dan:
•CCRi< 180gon/km : Tdt
• 180 gon/km < CCRi < 360 gon/km: Trung binh
• CCRi > 360 gon/km : Xau - Dd'i vdi cac dtrdng cong lien tiep:
• I CCRi - CCRi+1 I 1180 gon/km : Tdt
• 180 gon/km < |cCRi - CCRi+11 < 360 gon/km : Trung binh
• I CCRi - CCRi+1 I > 360 gon/km : Xau Ngoai anh htrdng ctia trj so suat thay doi gdc ngoat dudng cong de'n chat lugng khai thac dudng, he sd Itrc ma sat ngang cung la ye'u td quan trgng anh hudng den an toan va td'c do xe chay. Hieu sd gida Itrc ma sat ngang thie't ke'
{[IQ) va he so Itrc ma sat ngang yeu cau ()4,R)
bieu thj mdc do on djnh ddng hgc bao dam an toan cho xe chay khi vao dtrdng cong.
- Cdng thdc xac djnh he sd Itrc ma sat ngang thiet ke ()J,D):
(3.6)
\^D = - 1 . 127R
- Cdng thdc xac djnh he sd Itrc ma sat ngang
yeu cau (|XR):
HR = '' - i
127R " (3.7) Trong dd: Vgs : Td'c do khai thac (km/h)
Vd : Tdc do thie't ke (km/h)
TAP CHi CAU DLTdNG VIET NAM
KHOA HOC - CONG NGHE
R: ban kfnh dtrdng cong trdn (m) qua chfnh rut ra t d cac sd lieu khao sat:
igc: do ddc ngang sieu cao (%) Tieu chf danh gia nhtr sau:
- HD - ^R S 0.01
• - 0.04 < JXD - |j,R < 0.01
• H D - ^ R < - 0 . 0 4
Tren doan tuyen nghien cdu, nhieu dudng eong nam cd ban kfnh nhd han 500m nam d khu vtrc cae thj tran, khu dan cu ddng due noi cd bien bao han che td'c do V < 40km/h, hoac la nam d vj trf cac dau cau dang dugc xay dung, sda chda trong thdi gian nghien cdu.
Vi vay, nghien cdu nay chi tap trung danh gia td'c do khai thac tren mdt so dudng cong va xem xet danh gia mdc do dn djnh cua xe khi vao cac dudng cong nay thdng qua suat thay ddi gde ngoat dudng cong CCR va he sd Itrc ma sat ngang [i nhu de cap d tren.
Ke't qua tfnh toan cac thdng sd phue vu danh gia dieu kien xe chay trong cac dudng cong nghien cdu dugc tdng hgp trong Bang 2 dudi day.
Dudi day la cac ket
(1) Ket qua khao sat cho thay tieu chf ve he sd Itrc ma sat ngang hau het nam trong gidi han tdt, chi cd 3 dtrdng cong cd tieu chf he sd luc ngang nam trong gidi han trung binh. Td do co the cho rang tren doan tuye'n nghien cdu tdc dp khai thac Vgs ft chju anh hudng bdi he sd bam ngang gida banh xe vdi mat dudng.
Bang 2: Bang thong ke cac dudng cong va thong so' phuc vu danh gia Tdt
Trung binh Xau
sn
(1) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 28 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49
Doan (2) 8 12 14 15 16 24 31 34 39
40 42 44 45 46 47 49 50 52 53 54
55
59 62 63 65
ty trinh (3) 957+404 957+834 958+237 961+169 963+486 964+171 964+270 964+597 965+42 977+213 983+929 996+909 997+394 1002+202 1002+446 1004+96 1004+392 1004+879 1005+462 1008+59 1008+619 1010+664 1010+838 1010+911 1011+180 1013+662 1015+629 1018+552 1019+12 1021+949 1022+458 1025+517 1028+117 1028+561 1030+670 1031+316 1031+448 1031+506 1031+595 1031+926 1032+358 1032+628 1036+207 1036+530 1036+662 1036+903 1040+208 1042+608 1043+893
R (m)
(4) 133 192 487 866 800 662 146 116 253 894 650 510 482 343 339 326 340 355 860 170 127 180 250 211 330 240 601 280 395 470 512 323 314 600 419 336 278 182 330 270 417 350 258 378 1059 390 300 320 591
K (m) (5) 55.5 234.28 328.49 109.98 193.8 54.92 95.97 167.1 172.68 108.06 212.72 168.4 120.68 106.84 67.78 62.56 101.24
41.24 104.16 170.01 61.44 55.62 64.76 81.24 94.4 89.3 32.56 51.74 66.42 106.78 183.14 94.46 144.16 69.52 239.36 70.74 71.74 44.02 135.74 118.08 172.56 163.44 54.8 16.7 85.2 73.78 52.94 82.16 114.46
V85 km/h (6)
-
76
- -
50 62 79
-
54
69
-
60 76 58 45 76 78 59 71 50
54
-
70 49 71
Vtk km/h (7) 80 80 80 80 80 80 80 80 80
80 80 80 80 80 80 80 80 80 80 80
80
80 80 80 80
H D - H R
(8)
-
0.006
-
|E?^g|!flp^55.
V .0.023 0.002
-
0.080 0.081 ' "t 0.084
0.038 0 036
^'•0.01,?>:.^6„
-
0.122 '/-, 0.088
>#^/ 0 104 '-'' 0.015 fx,' 0.100
^/r' 0,057 IJ/J 0.123 j y 0.087 '^/ 0.010
0.005 0.008
>*i' 0 0 7 3 '*? 0.038 .^/ 0.026
^r?/ 0.091 ,;/,'. 0.110 ft: 0159 m-- 0.093
<?.'•; 0.114 :
?#'.r 0.066 AA.M7SU^.
-
0 039 , 0 098 •
CCRi (gon/km)
(9)
C C R i - CCR(i+1) (gon/km) (10)
•HJii^^MS^.^
331,77
f r i f s ^ KiMMM
• 4 , 7 f © ; : T 96.22
M P M
^BBBH^H
251.78 71.25 "
98,00 124.90 13216 185.71 187.91 195.40 187.35
\7§^.
fJ^-^M^
353.89 254.80 301.90 193.03 265.42
' lOSTMS
227.50 161.27'--'"'J 135.53 V
t*l2il^M
197.21 202.87 106.17 152.03 189 58 229 14 350.00 193.03 235.93 182.00 246.90
^^m^^
50.15 .^163.33 'i>
212 33 199.06 , .- 0 018 • . ; 107.7851
-340 08
..^mm..
- 2 1 9
99.09 -47.10
96.70 -
-39.55 -120.86
156,97 ,
>|j>42 90
^ 3 _ 2 4 _
»a_38-:--.
TAP CHI CAU OadNG VIET NAM
(2) Xet anh hudng cua suat thay ddi do cong
Td thdng ke trong bang 2 cho thay, theo tieu chi suat thay ddi do cong CCR, cac dudng eong tai cac ly trinh Km957+404, Km964+270, Km964+597, Kml008+619 gia trj suat thay ddi do cong CCR nam trong gidi han xau. Tai cac dudng cong nay can thiet phai cd bien phap cai thien nhu tang ban kfnh dudng cong hoac la cam bien bao hieu. Hien tai 4 dudng cong nay nam d eac doan qua khu dan eu cd han che tde do V = 40 km/h theo bien bao ngoai hien trudng.
Quan he gida trj sd CCR va td'c do Vgs duge the hien tren bieu dd hinh 6 dtrdi day.
— — j - „ „ „ i , „ ,
0 00 50 00 100 00 150,00 200,00 250 00 300,00 350 00 400,00 y u i ' l ! / I ' j r " - ; .' . CCR (Son/km)
Hinh 6. Quan he giffa toe do Vgg va CCR Td quan he gida td'c do khai thac Vgs va gia trj CCR ed the thay cac gia trj Vgs gan nhu dugc chia ra lam 2 khoang rd ret dd la: Vgs > 70 km/h dd'i vdi cac dudng cong cd CCR < 150 gon/km va Vg5 < 60 km/h dng vdi cac dudng cong cd CCR
> 180 gon/km. Dieu nay cho thay trj sd CCR ia mgt dai lugng cd anh hudng dang ke de'n td'c do khai thac Vg5. . ...
Phan tfch hdi quy gida Vgs va CCR thu dugc quan he tuye'n tfnh vdi he sd tuong quan r^ = 0-321: , . , , , . . . „ . . , . . . „ , , ^ , . .
Vg5 = 75.149-0.0885 CCR " • > (3.8) Trong dd: CCR la suat thay doi gdc ngoat dudng cong (gon/km). oa v s
(3) Xet anh htrdng cua ban kfnh dudng cong R de'n \/Q^: De danh gia anh htrdng cua ban kfnh dudng cong nam R dd'i vdi td'c do khai thac Vg5, trj sd Vgs tai cac doan cd td'c do han che V < 50 km/h dugc loai bd. Ket qua khao sat tde do Vgs tai cac dudng cong cdn lai the hien trong bang 3.
Bang 3: Bang tho'ng ke cac dirdng cong va toe do Vgs
L^trinh 961+169 965+42 977+213 983+929 1002+446 1004+392 1005+462 1011+180 1013+562
R (m) 866 253 894 650 339 340 860 330 240
V85 (Km/h) 76 50 62 79 54 56 69 76 58
Ly trinh 1021+949 1022+468 1028+117 1030+670 1032+628 1040+208 1042+608 1043+893
R (m) 470 512 314 419 350 300 320 591
V85 (Km/h) 76 78 59 71 54 70 49 71
90 80 ->
70 _ 60 •
| S 0 ' g 40 I-
^ 30 I 2 0 ; 10 f 0
Ghi chu,'.
BAn kinh R (m)
: Hoi qui iviyin linh; : Hoi qui LogHriclhim ... : Hdi qui da thirc b^c 3
Hinh 7. Quan he giffa toe do Vgg va ban kinh dudng eong R
Ke't qua cho thay hau het td'c do Vgs trong khoang td 49 km/h de'n 59 km/h tuang dng vdi eae ban kfnh td 240m de'n 350m. Dd'i vdi cac dudng cong ban kfnh R > 400m, td'c do Vg5 chu yeu nam trong khoang td 70 - 80 km/h. Str gia tang dang ke td'c do khai thac khi ban kfnh dudng cong Idn hon trj sd R = 400m phan anh dung quy djnh ve trj sd ban kfnh dudng cong nam tdi thieu thdng thudng, trj sd ban kfnh tdi thieu
khuyen cao nen dung theo tieu chuan TCVN 4054-05 (theo tieu chuan nay R = 400m la trj sd ban kfnh dtrdng cong nam tdi thieu thdng thudng tuong dng vdi td'c do thie't ke' V = 80 km/h).
TAP CHI CAU DUCJNG VIET NAM
KHOA HQC - C 6 N G N G H $
Mdi quan he gida tdc do Vg5 va ban kfnh dudng eong nam R dugc the hien qua mdt sd cdng thdc hdi quy nhtr sau:
- Hdi quy tuye'n tfnh ed he so tuong quan r' = 0.234
Vgs = 0.0228 R + 54.386 (3.9) - Hdi quy bac hai ed he so tuang quan f = 0.5
Vg5 = -0.0001 R^+ 0.1924 R+14.197 (3.10) Cac md hinh hdi quy khac theo Logarit, da thdc bac 2 hoac da thdc bae 3 v.v.. deu cd he so tuong quan nam trong 2 he sd ke tren.
(4) Xet anh hudng ddng thdi etia 3 yeu td la ban kinh dudng eong R, khoang each tTnh khdng ngang L va do bang phang (chi sd IRI) ta dugc quan he hdi quy vdi he sd tuong quan f = 0.297 nhu sau:
Vgg = 0.031 IRI + 0.121 L - 0.270 R + 46.317 (3.11) 4. KET LUAN
Ke't qua nghien cdu cho thay, td'c do khai thac cd tuong quan vdi mdt sd nhan td anh hudng nhu:
do bang phlng eija mat dudng khi IRI > 4 (he sd tuang quan f = 0.437), khoang each tmh khdng ngang L (r' = 0.539), ban kfnh dudng cong nam R (r^ = 0.5), suat thay ddi gdc ngoat dudng cong CCR {f = 0.321). Ngoai ra cae sd lieu khao sat cung chdng minh rang, td'c do khai thac giam dang ke khi xay ra mdt trong cac trudng hgp sau:
(1) mat dudng cd trj sd IRI > 4, (2) khoang each tmh khdng ngang L < 10m, (3) ban kfnh dudng cong nam R < 400m, va (4) suat thay doi gdc ngoat dudng cong CCR > 180 gon/km.
Vdi ke't qua ban dau trong viec nghien cdu cac ye'u td anh hudng de'n td'c do khai thac tren tuye'n qud'c Id I A doan t d Da Nang di Quang Ngai, nhdm tac gia bai bao kie'n nghj can sdm thtrc hien cac nghien cdu cd quy md Idn nham
tim ra mdt each djnh Idgng anh htrdng cua cac dieu kien khac nhau den td'c do khai thac dudng trong dieu kien Viet Nam nham dtra ra dugc cac ehl dan thie't ke va quan ly khai thac dudng mot each phu hgp giup nang cao td'c do xe chay va chat lugng sd dung dudng - van de dugc xem la cdn nhieu bat cap d Viet Nam hien nayQ
TAI LI§U THAM KHAO
[1] CHXHCNVN, Tieu chuan Viet Nam.
Dudng d td - Yeu cau thie't ke TCVN 4054-05, Ha Ndi 2005.
[2] Cac Bao cao ke't qua de'm xe cua Khu Quan ly Dudng bd V.
[3] Cae Bao cao thdng ke so vu tai nan giao thung cua Cung ty CP Quan ly va Xay dung Quang Nam - Da Nang, Cung ty CP Quan ly va Xay dung Quang Ngai.
[4] Hd so thiet ke ky thuat Dtr an nang cap cai tao mang ludi dtrdng bd, QL1A - doan Da Nang di Quang Ngai cua Ban quan ly dtr an dudng bo 2, do lien danh T u van BCEOM va Tuvan XDGT Nghe An lap.
[5] Tap bai giang Ky thuat giao thung cua T.S Vu Hoai Nam, trtrdng Dai Hgc Xay dung Ha Ngi.
[6] ThS. Do Trgng An. Nghien cdu de xuat mdt sd giai phap nang cao td'c do khai thac tuye'n Qud'c Id I A doan t d Da Nang di Quang Ngai.
Luan van cao hgc, trtrdng Dai hgc Xay dung, 2009, ngtrdi hudng dan: TS. Vu Hoai Nam.
[7] TS. Vu Hoai Nam. ThS. Do Duy Dinh, ThS.
Dd Trgng An, ThS. Pham Hdng Quang (2010).
Khao sat danh gia tdc do khai thac tren tuyen Qudc Id 1A doan t d D a Nang di Quang Ngdi. Tap chf Cau dudng sd 3/2010.
[8] Va mdt sd tai lieu nude ngoai khac.
TAP CHl CAU DLfONG VIET NAM