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MARCH 2014 INTAKE- SITE SURVEYING ( QSB60103 ) GROUP MEMBER: JOSHUA CHUA SHU MIN, KELLYANN HIEW YAU MEI, JAKE SIA CHYI SERN, GOH JENG JHIEH Site Surveying Report I Leveling Site Surveying (QSB60103) Mr. Chai Voon Chiet Joshua Chua Shu Min (0313572) Kellyann Hiew Yau Mei (0319532) Jake Sia Chyi Sern (0314396) Goh Jeng Jhieh (0315080)

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Page 1: Site surveying

MARCH 2014 INTAKE-

SITE SURVEYING

( QSB60103 )

GROUP MEMBER: JOSHUA CHUA SHU MIN, KELLYANN HIEW YAU MEI,

JAKE SIA CHYI SERN, GOH JENG JHIEH

Site Surveying Report I

Leveling

Site Surveying (QSB60103)

Mr. Chai Voon Chiet

Joshua Chua Shu Min (0313572)

Kellyann Hiew Yau Mei (0319532)

Jake Sia Chyi Sern (0314396)

Goh Jeng Jhieh (0315080)

Page 2: Site surveying

MARCH 2014 INTAKE-

SITE SURVEYING

( QSB60103 )

GROUP MEMBER: JOSHUA CHUA SHU MIN, KELLYANN HIEW YAU MEI,

JAKE SIA CHYI SERN, GOH JENG JHIEH

1.0 OBJECTIVE

The objective of leveling: -

To find the elevation of the given point with respect to some assumed

reference lines, datum.

To establish point at required elevation respect to datum.

To determine the difference in height of two discrete points

To analyze the probable errors that occurs while carrying out the

survey.

2.0 INTRODUCTION

Leveling is the determination of variations in altitude of points. It is usually

performed with and “engineer’s level” and a leveling staff or better known as

the “spirit leveling”.

There are situation that there is no Ordnance Bench Mark (OBM) which exist

near to a construction site. Henceforth, a temporary bench mark (TBM) must

be established. The leveling should be carried forward from the nearest OBM

to establish the TBM value.

When the heights of points above a datum is being determined, the values

are known as “reduced levels”

Page 3: Site surveying

MARCH 2014 INTAKE-

SITE SURVEYING

( QSB60103 )

GROUP MEMBER: JOSHUA CHUA SHU MIN, KELLYANN HIEW YAU MEI,

JAKE SIA CHYI SERN, GOH JENG JHIEH

2.1 TERMS USED FOR LEVELING

(a) Back-sight (BS)

Back-sight is the reading of the leveling rod in its unchanged position

when the leveling instrument has been taken to a new position.

(b) Intermediate sight (IS)

Intermediate sight is a reading taken between back-sight and foresight.

It is any reading taken on a point of unknown elevation from the same

set up of the level.

(c) Foresight (FS)

Foresight is basically the last reading taken towards a new station

before the instrument is shifted

(d) Turning Point (TP)

Turning Point is a capricious point, which allows the leveling to

continue from a new point. It is also known as change point (CP).

(e) Line of collimation (HI)

Line of collimation is basically the line that intersects with the cross

hair of the optical center of the telescope. The height of this line above

the datum is named as height of instrument or height of

collimation.

Page 4: Site surveying

MARCH 2014 INTAKE-

SITE SURVEYING

( QSB60103 )

GROUP MEMBER: JOSHUA CHUA SHU MIN, KELLYANN HIEW YAU MEI,

JAKE SIA CHYI SERN, GOH JENG JHIEH

2.1 OUTLINE OF APPARATUS

(a) Automatic Level

An automatic level is an optical instrument that is used to establish

checkpoints in the same horizontal plane.

1. Gun sight

2. Circular level (pond bubble)

3. Leveling Screw

4. Base Plate

5. Objective Lens

6. Focusing Knob

7. Horizontal fine motion screw

Figure: Automatic Level Image retrieved from

http://www.vpcivil.co.in/topcon-auto-levels-at-b2-at-b3-at- b4/

Figure: Sectional and Plan View of Automatic Level Image retrieved from

http://www.vermessungsseiten.de/englisch/vermtech/guide/levinfo.htm b4/

Page 5: Site surveying

MARCH 2014 INTAKE-

SITE SURVEYING

( QSB60103 )

GROUP MEMBER: JOSHUA CHUA SHU MIN, KELLYANN HIEW YAU MEI,

JAKE SIA CHYI SERN, GOH JENG JHIEH

8. Horizontal circle window

9. Horizontal circle setting ring

10. Reticle adjusting screw cover

11. Eyepiece

(b) Leveling Staff

Leveling staff or also called as leveling rod is an instrument used to

determine the differences in elevation n.

(c) Tripod

Figure: Leveling Staff Image retrieved from

http://www.qrbiz.com/buy_instruments-used

Figure: Tripod Image retrieved from

http://tbt-scietech.en.alibaba.com/product/345164680-

209881742/Aluminum_Tripod_for_Total_Station.html

Page 6: Site surveying

MARCH 2014 INTAKE-

SITE SURVEYING

( QSB60103 )

GROUP MEMBER: JOSHUA CHUA SHU MIN, KELLYANN HIEW YAU MEI,

JAKE SIA CHYI SERN, GOH JENG JHIEH

A tripod is a three-legged frame instrument, which allows the automatic

leveling device to be fixed unto the tripod.

2.2 SETTING UP AN AUTOMATIC LEVEL

STEP 1: Set up the tripod stand approximately above the chest height.

Ensure that it is stable and mount at the level on the top by stepping

on the tripod leg in order to drive it onto the ground.

STEP 2: Attach the automatic level onto the tripod stand by screwing

it.

STEP 3: Adjust the leveling screws until the bubble pond is situated

right at the center.

STEP 4: Before taking the reading, use the gun sight to aim in order to

make sure that the automatic level’s focusing range is relatively near

to the leveling staff.

STEP 5: Adjust the reticle until the crosshair is clear.

STEP 6: Fine-tune the objective lens until the leveling staff that you

are sighting is clear to read.

Page 7: Site surveying

MARCH 2014 INTAKE-

SITE SURVEYING

( QSB60103 )

GROUP MEMBER: JOSHUA CHUA SHU MIN, KELLYANN HIEW YAU MEI,

JAKE SIA CHYI SERN, GOH JENG JHIEH

3.0 FIELD DATA (RISE AND FALL)

ERROR DISTRIBUTION

= (100.033 – 100.000) / 11

= (0.033) / 11

= 0.003

3.1 ADJUSTED DATA (RISE AND FALL)

Back-sight Intermediate

Sight

Foresight Rise Fall Reduce

Level

Remarks

1.333 100.000 BM 1

1.640 3.640 2.307 97.693 TP 1 1.475 1.612 0.028 97.721 TP 2

1.385 1.548 0.073 97.648 TP 3 1.530 1.425 0.040 97.608 TP 4 1.280 1.270 0.260 97.868 TP 5

1.325 1.320 0.040 97.828 TP 6 1.290 1.525 0.200 97.628 TP 7

1.435 1.265 0.025 97.653 TP 8 3.045 1.370 0.065 97.718 TP 9

1.365 0.700 2.345 100.063 TP 10 1.395 0.030 100.033 BM 1

17.103 17.070 Σ

17.103

100.033

-17.070

-100.000

0.033

0.033

Back-sight Intermediate

Sight

Foresight Rise Fall Reduce

Level

Adjustment Final

Reduce Level

Remarks

1.333 100.000 BM 1

1.640 3.640 2.307 97.693 -0.003 97.690 TP 1

1.475 1.612 0.028 97.721 -0.006 97.715 TP 2

1.385 1.548 0.073 97.648 -0.009 97.639 TP 3

1.530 1.425 0.040 97.608 -0.012 97.596 TP 4

1.280 1.270 0.260 97.868 -0.015 97.853 TP 5

1.325 1.320 0.040 97.828 -0.018 97.810 TP 6

1.290 1.525 0.200 97.628 -0.021 97.607 TP 7

1.435 1.265 0.025 97.653 -0.024 97.629 TP 8

3.045 1.370 0.065 97.718 -0.027 97.691 TP 9

1.365 0.700 2.345 100.063 -0.030 100.033 TP 10

1.395 0.030 100.033 -0.033 100.000 BM 1

Page 8: Site surveying

MARCH 2014 INTAKE-

SITE SURVEYING

( QSB60103 )

GROUP MEMBER: JOSHUA CHUA SHU MIN, KELLYANN HIEW YAU MEI,

JAKE SIA CHYI SERN, GOH JENG JHIEH

4.0 FIELD DATA (HEIGHT OF COLLIMATION)

ERROR DISTRIBUTION

= (100.033 – 100.000) / 11

= (0.033) / 11

= 0.003

4.1 ADJUSTED FIELD DATA (HEIGHT OF COLLIMATION)

Back-sight Intermediate

Sight

Foresight Height of

Collimation

Reduce

Level

Remarks

1.333 101.333 100 BM 1

1.640 3.640 99.333 97.693 TP 1 1.475 1.612 99.196 97.721 TP 2

1.385 1.548 99.033 97.648 TP 3 1.530 1.425 99.138 97.608 TP 4 1.280 1.270 99.148 97.868 TP 5 1.325 1.320 99.153 97.828 TP 6

1.290 1.525 98.918 97.628 TP 7 1.435 1.265 99.088 97.653 TP 8

3.045 1.370 100.763 97.718 TP 9 1.365 0.700 101.428 100.063 TP 10

1.395 100.033 BM 1

17.103 17.07 Σ

17.103

100.033

-17.070

-100.000

0.033

0.033

Back-sight Intermediate Sight

Foresight Height of Collimation

Reduce Level

Adjustment Final Reduce Level

Remarks

1.333 101.333 100 BM 1 1.640 3.640 99.333 97.693 -0.003 97.69 TP 1 1.475 1.612 99.196 97.721 -0.006 97.715 TP 2

1.385 1.548 99.033 97.648 -0.009 97.639 TP 3 1.530 1.425 99.138 97.608 -0.012 97.596 TP 4 1.280 1.270 99.148 97.868 -0.015 97.853 TP 5 1.325 1.320 99.153 97.828 -0.018 97.81 TP 6

1.290 1.525 98.918 97.628 -0.021 97.607 TP 7 1.435 1.265 99.088 97.653 -0.024 97.629 TP 8 3.045 1.370 100.763 97.718 -0.027 97.691 TP 9 1.365 0.700 101.428 100.063 -0.03 100.033 TP 10

1.395 100.033 -0.033 100 BM 1 17.103 17.07 Σ

Page 9: Site surveying

MARCH 2014 INTAKE-

SITE SURVEYING

( QSB60103 )

GROUP MEMBER: JOSHUA CHUA SHU MIN, KELLYANN HIEW YAU MEI,

JAKE SIA CHYI SERN, GOH JENG JHIEH

Summary

Leveling is the determination of variations in altitude of points. In order to find

out the altitude, Back-sight (BS), Intermediate sight (IS) and Foresight (FS)

must be determined. The readings for BS, IS and FS can be taken using an

Automatic Level together with a leveling staff and a tripod. There are 2

methods that can be used to find the altitude – Height of Collimation Method

and Rise & Fall Method.