1 bg thuc hanh trac diadc

7/23/2019 1 BG Thuc Hanh Trac DiaDC

1/24

TRNG I HC NNG LM TP. H CH MINH

KHOA QUN L T AI V BT NG SN________

TI LIU HNG DN THC HNHMN TRC A I CNG

GV son KS. inhQuang Vinh

-Nm 2011-


2/24

Khoa Qun l t ai v Bt ng sn 2011 KS. inh Quang Vinh (0908708325)

Hng dn thc hnh mn Trc a i cng 2

BI 1. S DNG MY KINH V QUANG HC I. Cu to ca my kinh v quang hc.

II. Quy trnh t my trn mt trm o. - Bc 1. Di tm: l thao tc dng hai chn my a tm ca my trng vi tm mc trn mt t. - Bc 2. Cn bng s b: l thao tc dng cc c trn cc chn my a bt thy trn vo gia.

i vi nhng my khng c bt thy trn th dng ngay ng thy di cn bng s b. - Bc 3. Cn bng chnh xc: l thao tc dng cc c cn trn my a ng thy di vo gia.

III. o khong cch bng my kinh v quang hc v mia. Gi s cn o khong cch gia hai im ta thc

hin cc bc sau y:- t my kinh v ti mt im, dng mia ti mt

im.- Quay my ngm mia ri iu chnh tiu c

nhn r hnh nh ca mia.- Dng c vi ng ngang iu chnh ch di ca

li ch ch thp trng vo mt vch chn gn nht trn mia sau tnh khong cch t my n mia theo2 cch sau y:

+ Cch 1: m t ch di ln ch trn xem lbao nhiu centimet th cng chnh l s mttnh t my n mia. Cch ny nn dng khi khongcch t my n mia ngn.

+ Cch 2: Ly hiu s c ca ch trn v ch

di ri cng thm khong l. Cch ny nn dng khikhong cch t my n mia di.* Lu : Trng hp ni trn p dng cho hng snhn K=100, tc l 1cm trn mia tng ng vi1m ngoi thc a. Nu K=200 th 1cm 2m.* V d: Theo hnh 1 th khong cch t my n mial 9,2m. Cn gi tr trn hnh 2 l 20,7m.


3/24



IV. Cch c gi tr gc ca mt s my kinh v quang hc. 1. My THEO 010B.a. Cch c s bn ng.

- Bn ng ca my THEO 010B l loi bn ng khc vch lin tc nn gi tr c cchnh l gi tr gc thin nh (Z). Bn ng khc vch lin tc c gi tr t 01800.

- Gc thin nh (Z) l gc hp bi hng tia ngm vi hng nh tri.

b. Cch c s bn ngang.

2. My DAHLTA.a. Cch c s bn ng.

- Bn ng ca my DAHLTA l loi bn ng khc vch lin tc nn gi tr c c ch nh

l gi tr gc thin nh (Z). Bn ng ca my DAHLTA c chia vch t 0200gr (vi 1gr = 100c;1c =100cc).


4/24



b. Cch c s bn ngang.- Bn ngang ca my DAHLTA c chia thnh 400 phn bng nhau, mi phn nh vy l mt

grat (gr), (vi 1gr = 100c; 1c =100cc).

3. My 3T5K.a. Cch c s bn ng.

- Bn ng ca my 3T5K l loi bn ng khc vch i xng nn gi tr c c trnbn ng chnh l gi tr gc ng (V). Bn ng khc vch i xng c gi tr t 0900.

- Gc ng (V) l gc hp bi hng tia ngm vi hng nm ngang.


4. My 4T30.a. Cch c s bn ng.

- Bn ng ca my 4T30 l loi bn ng khc vch i xng nn gi tr c c trn bn ng chnh l gi tr gc ng (V). Bn ng khc vch i xng c gi tr t 090 0.



5/24



V. Cch o gc bng.1. Phng php o n gin.

Phng php ny p dng khi s hng bng 2. Gi tr thu c sau khi o l gi tr gc. Gi s cn o gc gia 3 im: GPS6, KV1-1, KV1-2 thao tc o c th nh sau: t my kinh v ti

im KV1-1.- v tr thun knh: Ngm im GPS6 v a bn ngang v 00 sau quay my ngm im

KV1-2 v c s c trn bn ngang v ghi vo s o gc.- o knh: Ngm chnh xc im KV1-2 ri c s trn bn ngang v ghi vo s sau quay

my ngm im GPS6 ri c s trn bn ngang v ghi vo s. n y l kt thc mt ln o ngin.* Lu : Nu gc phi o nhiu ln th gi tr ban u ca mi ln o s thay i mt gi tr c tnh theo

cng thc :n

1800

. Trong n l tng s ln o.

2. Phng php o ton vng.Phng php ny p dng khi s hng 3. Gi tr thu c sau khi o l gi tr hng.

Gi s cn o gc bng phng php o ton vng ti im GPS6 n cc hng KV1 -3, GPS5,KV1-1 nh hnh v th thao tc o c th nh sau: t my kinh v ti im GPS6.

- v tr thun knh: Ngm im KV1-3( im c khong cch trung bnh so vi cc hng cnli) ri a gi tr bn ngang v 0 0 sau ln lt ngm v cc im GPS5, KV1 -1 v KV1-3 cs c ca bn ngang v ghi v s o gc.

- o knh: Ngm chnh xc im KV1-3 ri c s trn bn ngang v ghi vo s sau ln ltquay my ngm im KV1-1, GPS5 v KV1-3 ri c s trn bn ngang v ghi vo s. n y l ktthc mt ln o ton vng.* Lu : Nu gc phi o nhiu ln th gi tr ban u ca mi ln o s thay i mt gi tr c tnh theo

cng thc :n

1800

. Trong n l tng s ln o.


6/24



Ngi o: Nguyn Vn Hng TRM O: KV1-1 Loi my: PentaxNgi ghi: L Vn Nam S my: 123456Bt u lc: 7h 30 Thi tit: NngKt thc lc: 8h 00

S LIU O CNH NG CHUY NCnh t: KV1-1 n: GPS6 Cnh t KV1-1 n: KV1-2 Cnh t. n Cnh t. n

L1= 99.942 m L1= 95.754 m L1= .... L1= ....L2= 99.938 m L2= 95.756 m L2= ........ L2= ........LTB= 99.940 m LTB= 95.755 m LTB= . LTB= .

L no

i mngm

S cbn tri

S cbn phi

2CTr gi gcna ln o

Tr gi gcmt ln o

Tr gi gccc ln o

Ghi ch

1 GPS6 0 00 00 180 00 00 00 252 10 34252 10 33

KV1-2 252 10 34 72 10 32 +02 252 10 32252 10 34

2 GPS6 90 00 00 270 00 02 - 02 252 10 35252 10 35

KV1-2 342 10 35 162 10 37 - 02 252 10 35

S o ni


7/24



Ngi o: Nguyn Vn Hng TRM O: GPS6 Loi my: PentaxNgi ghi: L Vn Nam S my: 123456Bt u lc: 8h 15 Thi tit: NngKt thc lc: 9h 10

S LIU O CNH NG CHUY NCnh t: GPS6 n: KV1-3 Cnh t GPS6 n: KV1-1 Cnh t.n Cnh t.n

L1= 128.381 m L1= 99.939 m L1= .... L1= ....L2= 128.379 m L2= 99.941 m L2= ........ L2= ........LTB= 128.380 m LTB= 99.940 m LTB= . LTB= .

L no

i mngm

S cbn tri

S cbn phi

2CTr gi hng

na ln oTr gi hng

mt ln oTr gi hng

cc ln oGhi ch

1 KV1-3 0 00 00 180 00 02 - 02 0 00 00 0 00 01 0 00 00 Quy 0= 202

GPS5 156 11 33 336 11 31 +02 156 11 33 156 11 32 156 11 30 156 11 3131

KV1-1 279 38 18 99 38 16 + 02 279 38 18 279 38 17 279 38 15 279 38 1616

KV1-3 0 00 04 180 00 02 +02 0 00 04 0 00 03

2 KV1-3 90 00 00 270 00 00 00 90 00 00 90 00 00 0 00 00 Quy 0= 90 00 0100 156 11 31

GPS5 246 11 33 66 11 33 00 246 11 33 246 11 33 156 11 3233 123 26 45

KV1-1 9 38 19 189 38 17 + 02 9 38 19 9 38 18 279 38 1717

KV1-3 90 00 03 270 00 01 +02 90 00 03 90 00 02

S o ni


8/24

BI 2. HAI BI TON TRC A C BN

I. Bi ton thun.1. Ni dung bi ton thun.

- Cho 1 im c ta )( ,YXA AA , khong cch gia 2 im AB l SAB v gc phng

v ca cnh AB l AB .- Tnh ta ca im )( ,YXB BB .

2. Cch tnh bi ton thun.Theo hnh v, ta im B c tnh nh sau:

XXX ABAB YYY ABAB

Trong :

CosSX ABABAB . SinSY ABABAB .

* Lu : tnh ton nhanh cc gi tr X v Y bng my tnh cm tay ta thc hin nh sau:

II. Bi ton nghch.1. Ni dung bi ton nghch.

- Cho 2 im bit ta )( ,YXA AA , )( ,YXB BB .

- Tnh khong cch gia hai im AB SAB , gc phng v ca cnh AB AB .2. Cch tnh bi ton nghch.

- Tnh khong cch gia 2 im AB:

Sin

Y

Cos

XYXSAB

AB

AB

ABAB

22

- Tnh gc phng v ca cnh AB:

XY

AB

ABAB

arctg

* Lu : tnh ton nhanh SAB v AB bng my tnh cm tay ta thc hin nh sau:


9/24



BI 3. MT S NG DNG CA MY KINH V TRONG TRC A I. o chi tit bng phng php ta cc.

- Bc 1. t my trn mt im trm o (di tm, cn bng s b, cn bng chnh xc). - Bc 2. nh hng: l vic ngm ng knh v mt trm o khc v a bn ngang v 0 0.- Bc 3. o chi tit: l vic quay my ngm n mia dng ti cc im chi tit (gc ranh, gc

ng, gc ngot ca sng sui) thu thp cc s liu v gc v cnh ri ghi vo trong s o chitit.II. o khong cch gin tip.

Khong cch o c t my n mia ngi ta gi lkhong cch trc tip, cn khong cch gia hai mia c gil khong cch gin tip.Gi s cn o khong cch gia 2 im dng mia B v C ta lmnh sau:

- t my ti 1 im bt k (A) sao cho c th ngm ncc im dng mia (B, C).

-Ngm mia dng ti B v C ri o gc v o khong cch t my n 2 mia ta c cnh bv c nh hnh v.

- Tnh khong cch gin tip (a) theo cng thc:

Coscbcba ...222

III. o gc dn tip.Gc o c ti im t my ngi ta gi l gc o trc tip,cngc xc nh c ti cc im khng t my ngi ta gi l gco gin tip. Gi s cn xc nh 2 gc B v C nh hnh v ta thc

hin nh sau:- t my kinh v ti im A, dng mia ti 2 im B v C.- Ngm mia dng ti B v C ri o gc v o khong

cch t my n 2 mia ta c cnh b v c nh hnh v. - Tnh khong cch gin tip (a) theo cng thc:

Coscbcba ...222

- Tnh gc B v C theo cng thc:

IV. o, tnh ta ca mt im bng phng php im dn (Cc ph).

Gi s cn tnh ta im T khi c cc s liu gc v sliu o nh hnh v ta tin hnh nh sau:

- Tnh gc phng v ta cho cnh gc )(AB :

0547129 "'0

AB - Tnh gc phng v ta cho cnh BT:

1800

traitruocsau (1)

hoc 1800

phaitruocsau (2)


10/24



Theo hnh v, gc o c l gc tri nn p dng cng thc (1), tc l:

451770180 "'00

^

BABBT - Tnh s gia ta ca cnh BT.

CosSX BTBTBT . SinSY BTBTBT .

- Tnh ta cho im T:

xXX BTBT yYY BTBT

V. o tnh din tch bng phng php ta vung gc.

1. o chi tit cc im cn tnh din tch bng phng php ta cc. - t my kinh v ti im A.

- nh hng v im B.- Quay my n cc im chi tit 1, 2, 3 thuthp cc s liu o gc v cnh ri ghi vo s o chitit.

2. Tnh ton ta cho cc im chi tit.TT

S x y X Y1 40 30 30 60,5 24 33 46 55,025 25,149 555,025 625,149

2 60 45 15 80.0 44 48 31 56,757 56,379 556,757 656,379

3 80 50 50 70,9 64 54 06 30,074 64,206 530,074 664,206

- Tnh gc phng v cnh gc: 1603164 "'0

BA

- Tnh gc phng v cho cc cnh n cc im chi tit.

1800

traitruocsau

hoc 180

0

phaitruocsau

- Tnh s gia ta x, y cho cc cnh n cc im chi tit.- Tnh ta cho cc im chi tit.

xxx AiAi yyy

AiAi

STT

S1 40 30 30 60,5

2 60 45 15 80.0

3 80 50 50 70,9


11/24



3. Tnh din tch.C th p dng 1 trong hai cng thc sau y tnh din tch:

)(11

12 YYXP ii

n

i

)(11

12 XXYP iin

i

Theo hnh v, din tch ca vng 123 c tnh nh sau:

mYYXYYXYYXYYXP iin

i

2

243132021111

866,8462 )()()()(

Trong : ));););141433

(((( yyxxyyxx oo .VI. o chiu cao cng trnh. xc nh chiu cao ca mt cng trnh ta lm nh sau:

- t my ti mt im bt k sao cho khi t my trnim ny c th nhn thy nh v chn cng trnh.

- Dng mia chn cng trnh v xc nh khong cchngang t my n mia (D).

-Ngm ng knh ln nh cng trnh ri c gi tr gcng (V1).

-Ngm ng knh xung chn cng trnh ri c gi trgc ng (V2).

- Tnh chiu cao cng trnh (H) theo cng thc:

HHH 21 Trong : VtgDH 11 .

VtgDH 22 . VII. Giao hi thun.

Giao hi thun l vic t my trn 2 im bit ta (A, B) v o cc gc n im cn xcnh ta (C) xc nh ta cho im (C).

Gi s t my kinh v ti A v B ngm v Cv o c 2 gc nh hnh v. Khi cc bc tnhton ta cho im C c thc hin nh sau:

im S X Y X Y

C 1051,964 779,94140 03 07 590,446 +451,964 +379,941

A 70 30 15 600.000 400.000110 33 22 854,400

B 40 15 20 300.000 1200.000330 48 42 861,335 +751,964 -420,057

C 1051,964 779,943


12/24



1. Tnh gc phng v ta cho cnh gc.

2233110 "'0

AB 2233290 "'0

BA

2. Tnh gc phng vcho cnh AC v BC.

070340180 "'00

BAAC

4248330180 "'00

^

BABBC 3. Tnh gc C:

251469180 "'0

^0

^

)( BC 4. Tnh khong cch AC v BC.

mSinBSinCSS ABAC 446,590.

mSinASinCSS ABBC 335,861.

5. Tnh s gia ta cho cnh AC v BC.6. Tnh ta cho im C theo im A.

XXX ACAA

C

YYY ACAA

C 7. Tnh ta cho im C theo im B.

XXX BCBB

C

YYY BCBB

C

8. Tnh ta trung bnh cho im C.

mXXXB

C

A

CC 964,1051

2

mYYYB

C

A

CC 942,779

2


13/24



BI 4. XY DNG LI KHNG CH MT BNG I. nh ngha li khng ch mt bng.

Li khng ch mt bng l h thng cc im c lin quan hnh hc cht ch vi nhau. Cc im nyc nh du ngoi thc a bng cc mc c bit v c xc nh ta thng nht theo h ta quc giahoc theo h ta gi nh.II. Nguyn tc xy dng li khng ch.

- T tng th n cc b.- T chnh cc cao n chnh xc thp.

III. H thng li khng ch cc cp.1. Li Nh nc.2. Li a chnh c s.3. Li a chnh.4. Li khng ch o v.

IV. Cc dng li ng chuyn kinh v.1. im dn (Cc ph).

2. ng chuyn treo.

- L ng chuyn xut pht t mt im gc, saukhi i qua cc im ng chuyn thkhng khp v imgc no khc.

3. ng chuyn khp kn.

- L ng chuyn xut pht t mt im gc, sau khii qua cc im ng chuyn th khp v im gc ban u.

4. ng chuyn ph hp.

- L ng chuyn xut pht t mt im gc, sau khii qua cc im ng chuyn th khp v im gc khc.

5. ng chuyn 1 im nt.

6. ng chuyn nhiu im nt.


14/24



V. Quy trnh xy dng li khng ch mt bng.- Bc 1: Thu thp s liu, ti liu, bn , nh hng khng.- Bc 2: Kho st thc a- Bc 3: Thit k s b li khng ch trn bn hoc trn nh.- Bc 4: Chn im, chn mc ngoi thc a- Bc 5: o khng ch

- Bc 6: Tnh chuyn ta cc im gc (nu cn).- Bc 7: Tnh ton bnh sai

VI. Ni dung o c trong li ng chuyn.1. o cnh.2. o gc.

a. Phng php o n gin.b. Phng php o ton vng.

VII. Tnh ton bnh sai.


15/24



A - BNH SAI GN NG NG CHUYN KINH V PH HP

I. S li

II. S liu gcSTT X (m) Y (m)

GPS1 1200000.000 600000.000

GPS2 1200078.220 600115.970

GPS3 1200023.020 600360.660

GPS4 1200061.940 600490.430

III. Bng tnh ng chuyn

imV

S (m)Vx

X(m)Vy

Y(m) X(m) Y(m)GPS1 1200000.000 600000

+ 02 56

000

03

GPS2 23104839 - 0.001 + 0.007 1200078.220 600115+ 02 107 48 44 91.360 - 27.947 + 86.980

KV1-1 14905457 0.000 + 0.007 1200050.272 600202+ 01

77

043

43

83.220 + 17.688 + 81.318

KV1-2 22204443 0.000 + 0.007 1200067.960 600284+ 02 120 28 27 88.612 - 44.940 + 76.371

GPS3 13204950 1200023.020 60036073

018

19

GPS4 1200061.940 600490

Tng 73701809 263.192 - 55.199 + 244.669


16/24



IV. Cc bc tnh ton bnh sai1. Tnh gc phng v cnh gc: 030056

"'0

21

GPSGPS v 191873 "'0

43

GPSGPS

2. Tnh tng cc gc o: o= 737018093. Tnh tng cc gc l thuyt:

LT

= (cui u) + ( + 2)x1800

hoc LT= (cui u) + ( - 2)x1800

Trong : l s im cn xc nh to .

Theo hnh trn : 180)22(2143

GPSGPSGPSGPS

LT

1618737 "'0

4. Tnh sai s khp gc f

:

7"

LTo

f 5. Tnh sai s khp gc cho phpfcp :

gmf cp

"2

Trong : - g : tng s gc o ca ng chuyn- "m : Sai s trung phng o gc. Sai s ny quy nh c th cho

tng cp li. V d theo quy phm thnh lp bn a chnh c th i vi ngchuyn KV1 v KV2 th "15m . Vy trong trng hp ny "604"152 f cp 6. So snh f

vf

cp:

- f>fcp th kim tra li kt qu tnh ton, nu kt qu tnh ton khng c sai stth tin hnh xc nh gc no sai tin hnh o li gc .

- ffcp th tin hnh tnh s hiu chnh v gc phn phi cho cc gc.7. Tnh s hiu chnh v gc (V) v phn phi cho cc gc:

4

)"7(

gfv

Tc l: 3 gc s hiu chnh (+2), cn li gc c s chnh lch khong cch gia2 cnh nh nht s hiu chnh (+1).8. Kim tra fv

9. Tnh gc phng v to cho cc cnh ng chuyn

180( 0) Vtraitruocsau

hoc 180( 0) Vpha itruocsau

10. Kim tra180(

0

1 )

Vtraincuoi hoc 180(

0

1 )

Vpha incuoi

- Theo hnh trn ta c: 191873180( "'00

31243 )

VtraiGPSKVGPSGPS 11. Tnh s gia to ),( yx cho cc cnh:


17/24



12. Tnh tnh

xv

tnh

y

)(199.55 mtnh

x

)(669.244 mtnh

y

13. Tnh sai s khp s gia to ff yx v )(001.0)( mxxf ucuoi

tnh

x

lthuyt

x

tnh

xx

)(021.0)( myyf ucuoi

tnh

y

lthuyt

y

tnh

yy

14. Tnh sai s khp cnh fs

)(021.022

mfff yxs

15. Tnh sai s khp tng iT

1

12532

11

sTf s

16. So snhT

1 viTcp

1

-Tcp

1c quy nh c th cho tng cp li. V d theo quy phm thnh lp bn

a chnh c, vng nng thn th4000

11

Tcpi vi KV1 v

2000

11

Tcpi vi KV2.

-Nu TcpT11 th kim tra li kt qu tnh ton, nu kt qu tnh ton khng c sai

st th tin hnh xc nh cnh no sai tin hnh o li cnh .

- NuTcpT11

th tin hnh tnh s hiu chnh v s gia to vv yx v ri hiu

chnhcho cc cnh.17. Tnh s hiu chnh v s gia to vv yx v ri hiu chnh cho cc cnh.

sf

v ixxs

sf

v iy

y

s

18. Kim tra cc gi tr:

fv xx fv yy 19. Tnh to cc im:

vxx xxtrucsau vyy yytrucsau


18/24



B - BNH SAI GN NG NG CHUYN KINH V KHP KN

I. S li

II. S liu gcSTT X (m) Y (m)

GPS5 1200013.640 600807.680

GPS6 1200043.450 600955.380

III. Bng tnh ng chuyn

im V

S (m)Vx

X(m)Vy

Y(m) X(m) Y(m)GPS5 1200013.640 600807.

- 03 78

035

22

GPS6 12302645 0.000 + 0.003 1200043.450 600955.- 02 22 02 04 99.940 +92.640 + 37.494

KV1-1 25201034 0.000 + 0.003 1200136.090 600992- 02

94

012

36

95.755 -7.030 + 95.497

KV1-2 26903834 0.000 + 0.004 1200129.060 601088- 02 183 51 08 113.428 - 113.172 -7.620

KV1-3 27803247 -0.001 + 0.005 1200015.888 601080- 02

28202353 128.380 +27.563 -125.386GPS6 15601131 1200043.450 600955.

258035

22

GPS5 1200013.640 600807.

Tng 1080 00 11 437.503 +0.001 - 0.015


19/24



IV. Cc bc tnh ton bnh sai1. Tnh gc phng v cnh gc: 223578

"'0

65

GPSGPS v 2235258 "'0

56

GPSGPS 2. Tnh tng cc gc o: o= 1080000113. Tnh tng cc gc l thuyt:

-Nu o cc gc ngoi ca a gic: 1080180 00

)2( cLT

-Nu o cc gc trong ca a gic: 180

0)2(c

LT

Trong : c l tng s cnh cn o ca ng chuyn

4. Tnh sai s khp gc f:

11"

Lythuyto

f 5. Tnh sai s khp gc cho php fcp :

gmf cp

"2

Trong : - g : tng s gc o ca ng chuyn- "m : Sai s trung phng o gc. Sai s ny quy nh c th cho tng cpli. V d theo quy phm thnh lp bn a chnh c th i vi ng chuyn KV1v KV2 th "15m .6. So snh fv fcp:

- f> fcp th kim tra li kt qu tnh ton, nu kt qu tnh ton khng c sai stth tin hnh xc nhgc no sai tin hnh o li gc .

- f fcp th tin hnh tnh s hiu chnh v gc phn phi cho cc gc.7. Tnh s hiu chnh v gc (V) v phn phi cho cc gc:

5"11

gfv

Tc l: 4 gc s hiu chnh (-2), cn li gc c s chnh lch khong cch gia 2cnh ln nht s hiu chnh (-3).8. Kim tra fv

9. Tnh gc phng v to cho cc cnh ng chuyn

180( 0) Vtraitruocsau

hoc 180( 0) Vpha itruocsau

10. Kim tra180(

0) Vtraitruocsau

11. Tnh s gia to ),( yx cho cc cnh:

12. Tnh tnh

xv

tnh

y

)(001.0 mtnh

x )(015.0 m

tnh

y


20/24



13. Tnh sai s khp s gia to ff yx

v

)(001.0)( mxxf ucuoitnh

x

lthuyt

x

tnh

xx

)(015.0)( myyf ucuoi

tnh

y

lthuyt

y

tnh

yy

14. Tnh sai s khp cnh fs )(015.0

22

mfff yxs

15. Tnh sai s khp tng iT

1

29166

11

sTf

s

16. So snhT

1 viTcp

1

-Tcp

1c quy nh c th cho tng cp li. V d theo quy phm thnh lp bn

a chnh c, vng nng thn th4000

11

Tcpi vi KV1 v

2000

11

Tcpi vi

KV2.

-NuTcpT11

th kim tra li kt qu tnh ton, nu kt qu tnh ton khng c sai

st th tin hnh xc nh cnh no sai tin hnh o li cnh .

-Nu TcpT11 th tin hnh tnh s hiu chnh v s gia to vv yx v ri hiu

chnh cho cc cnh.17. Tnh s hiu chnh v s gia to vv yx v ri hiu chnh cho cc cnh.

sf

v ixx s

s

fv i

y

y s

18. Kim tra cc gi tr:

fv xx

fv yy 19. Tnh to cc im

vxx xxtrucsau

vyy yytrucsau


21/24



BI 5. XY DNG LI KHNG CH CAOI. H thng li khng ch cao.Li khng ch cao ca Vit Nam gm 3 cp:

- Li khng ch cao Nh nc (I IV).- Li khng ch cao k thut.- Li khng ch cao o v.

II. Mt s dng ng chuyn cao.

1. ng chuyn treo.

2. ng chuyn khp kn.

3. ng chuyn ph hp.

4. ng chuyn 1 im nt.

5. ng chuyn nhiu im nt.


22/24



III. Cc phng php o chnh cao.1. Phng php o cao lng gic.

Trong phng php o cao lng gic ngi ta s dng tia ngm nghing ca my kinh v xcnh chnh cao gia 2 im. Gi s cn xc nh chnh cao gia 2 im AB ta t my knh v ti imA, dng mia ti im B sau o v thu thp cc s liu sau y:

- DAB : Khong cch ngang t my n mia- L : Chiu cao tia ngm (t mt mc n ch gia li ch ch thp)- i: chiu cao my (t mt mc n trc quay ng knh)- V: Gc ng. Nu yu cu xc nh hAB vi chnh xc cao th phi o V 2 v tr bn

(thun knh, o knh) v o 1 ln bng phng php 3 ch hoc o 3 ln bng phng php 1 ch.

Khi chnh cao gia 2 im AB l hAB c tnh theo cng trc sau y:LitgVDh ABAB

-Nu 0hAB c ngha l im dng mia cao hn im dng my.-Nu 0hAB c ngha l im dng mia thp hn im dng my.

2. Phng php o cao hnh hc (o thu chun). Trong phng php o thu chun ngi ta s dng tia ngm ngang ca my thu chun xc

nh chnh cao gia 2 im. Da vo cch t my thu chun khi o chnh cao ta c 2 cch o thuchun sau y:a. o thu chun pha trc.

* Thao tc o: Gi s cn xc nh chnh cao gia 2 im A v B ngi ta t my thu chun ti A,dng mia ti B v tin hnh thu thp cc s liu sau y:

- Chiu cao my (i).- Chiu cao ch gia ca mia dng ti B.


23/24



* Tnh chnh cao (hAB ): tihAB b. o thu chun t gia.

* Thao tc o: Gi s cn xc nh chnh cao gia 2 im A v B ngi ta t my thu chun gia 2im AB v dng mia ti 2 im ny ri tin hnh thu thp cc s liu sau y:

- Chiu cao (s) ca ch gia dng ti mia sau (mia dng ti im bit cao).

- Chiu cao (t) ca ch gia dng ti mia trc (mia dng ti im cha bit cao).* Tnh chnh cao (hAB ):

tshAB

IV. Cc sai s trong o thu chun v cch khc phc. TT Loi sai s Cch khc phc

1 Mia khng thng ng Gn ng thu trn trn mia2 Mia b ln trong qu trnh o Dng mia trn mia3 Sai s c s trn mia Cn thn trong qu trnh c s4 My b ln trong qu trnh o t my ni n nh, chc chn

5

Sai s gc i t my thu chun gia 2 imcn o6 Sai s khi ghi s, tnh ton h Cn thn trong qu trnh ghi s, tnh ton h7 nh hng ca cong tri t o thu chun t gia8 iu kin ngoi cnh (chit quang khng

kh, thiu nh sang trn mc tiu..)Chn thi im o thch hp

V. Tnh ton bnh sai li thu chun.1. Bnh sai gn ng ng chuyn cao ph hp. a. hnh.

Hnh III.9

b. S liu gc.STT Tn im cao (m)

1 A 50.0002 B 55.000


24/24



c. Cc bc bnh sai.Tn im )(mhi )(mSi )(mVhi )(mHi

A 50.000

+1.523 142.0 -0.0031 51.520

+2.324 150.0 -0.003

2 53.841+1.482 125.0 -0.002

3 55.321-0.318 152.7 -0.003

B 55.000Tng 569.7

- Bc 1: Tnh sai s khp cao f h

:

mmHHhhhf daucuoidolythuyetdoh 11)( - Bc 2: Tnh sai s khp cao cho php:

+ V d li cao k thut khi o vng ng bng: mmf Lmm

hcp 3850

vi L l chiu di ng chuyn tnh bng km.

- Bc 3: so snh f h

vi f hcp

+ Nu ffh hcp th kim tra li kt qu o.

+ Nu ffh hcp th tin hnh tnh s hiu chnh phn phi sai s khp chnh cao.

- Bc 4: Tnh s hiu chnh Vhi v phn phi sai s khp chnh cao

SL

fV i

h

hi

- Bc 5: Kim tra: fV hhi - Bc 6: Tnh cao cho cc im:

VhHH hiiii 1 - Bc 7: Kim tra:

VhHH hnnncuoi 1

1 bg thuc hanh trac diadc

Documents