section i surveying measurements -...
TRANSCRIPT
![Page 1: Section I Surveying Measurements - Weeblykamalmahmed.weebly.com/uploads/4/6/9/8/46985149/3-_horiz_and_slo… · Section I Surveying Measurements Leveling, horizontal and slope](https://reader030.vdocuments.net/reader030/viewer/2022021501/5a9e30707f8b9a36788c76e5/html5/thumbnails/1.jpg)
Section ISurveying Measurements
Leveling, horizontal and slope distance, angles and directions
2. Horizontal and Slope Distances
![Page 2: Section I Surveying Measurements - Weeblykamalmahmed.weebly.com/uploads/4/6/9/8/46985149/3-_horiz_and_slo… · Section I Surveying Measurements Leveling, horizontal and slope](https://reader030.vdocuments.net/reader030/viewer/2022021501/5a9e30707f8b9a36788c76e5/html5/thumbnails/2.jpg)
Horizontal Distance Measurement
TapeOdometer
Subtense BarStadiaEDM
Readings: 6-1,6-4, 6-6, 6-7,6-8, 6-14, 6-17 to 6-24
Readings: 6-1,6-4, 6-6, 6-7,6-8, 6-14, 6-17 to 6-24
![Page 3: Section I Surveying Measurements - Weeblykamalmahmed.weebly.com/uploads/4/6/9/8/46985149/3-_horiz_and_slo… · Section I Surveying Measurements Leveling, horizontal and slope](https://reader030.vdocuments.net/reader030/viewer/2022021501/5a9e30707f8b9a36788c76e5/html5/thumbnails/3.jpg)
Tape Measurement• Accuracy and speed considerations for civil
engineers.• Sources of Errors:
• Incorrect length of the tape• Temperature difference• Sag• Poor alignment• Tape not horizontal• Improper Plumbing
![Page 4: Section I Surveying Measurements - Weeblykamalmahmed.weebly.com/uploads/4/6/9/8/46985149/3-_horiz_and_slo… · Section I Surveying Measurements Leveling, horizontal and slope](https://reader030.vdocuments.net/reader030/viewer/2022021501/5a9e30707f8b9a36788c76e5/html5/thumbnails/4.jpg)
![Page 5: Section I Surveying Measurements - Weeblykamalmahmed.weebly.com/uploads/4/6/9/8/46985149/3-_horiz_and_slo… · Section I Surveying Measurements Leveling, horizontal and slope](https://reader030.vdocuments.net/reader030/viewer/2022021501/5a9e30707f8b9a36788c76e5/html5/thumbnails/5.jpg)
![Page 6: Section I Surveying Measurements - Weeblykamalmahmed.weebly.com/uploads/4/6/9/8/46985149/3-_horiz_and_slo… · Section I Surveying Measurements Leveling, horizontal and slope](https://reader030.vdocuments.net/reader030/viewer/2022021501/5a9e30707f8b9a36788c76e5/html5/thumbnails/6.jpg)
![Page 7: Section I Surveying Measurements - Weeblykamalmahmed.weebly.com/uploads/4/6/9/8/46985149/3-_horiz_and_slo… · Section I Surveying Measurements Leveling, horizontal and slope](https://reader030.vdocuments.net/reader030/viewer/2022021501/5a9e30707f8b9a36788c76e5/html5/thumbnails/7.jpg)
Other methods
• Odometer• Subtense Bar• Stadia
![Page 8: Section I Surveying Measurements - Weeblykamalmahmed.weebly.com/uploads/4/6/9/8/46985149/3-_horiz_and_slo… · Section I Surveying Measurements Leveling, horizontal and slope](https://reader030.vdocuments.net/reader030/viewer/2022021501/5a9e30707f8b9a36788c76e5/html5/thumbnails/8.jpg)
Electronic Distance Measurement
• Early types:• Transmit light, measure up to 25 miles• Transmit microwaves, measure up to 50
miles• Classification of EDM:
• Electro-optical: laser or infra red reflected from passive prism or surfaces, the US has installed a prism on the moon.
• Microwave: two positive units.
![Page 9: Section I Surveying Measurements - Weeblykamalmahmed.weebly.com/uploads/4/6/9/8/46985149/3-_horiz_and_slo… · Section I Surveying Measurements Leveling, horizontal and slope](https://reader030.vdocuments.net/reader030/viewer/2022021501/5a9e30707f8b9a36788c76e5/html5/thumbnails/9.jpg)
![Page 10: Section I Surveying Measurements - Weeblykamalmahmed.weebly.com/uploads/4/6/9/8/46985149/3-_horiz_and_slo… · Section I Surveying Measurements Leveling, horizontal and slope](https://reader030.vdocuments.net/reader030/viewer/2022021501/5a9e30707f8b9a36788c76e5/html5/thumbnails/10.jpg)
Topcon EDM attached to a WILD theodolite
![Page 11: Section I Surveying Measurements - Weeblykamalmahmed.weebly.com/uploads/4/6/9/8/46985149/3-_horiz_and_slo… · Section I Surveying Measurements Leveling, horizontal and slope](https://reader030.vdocuments.net/reader030/viewer/2022021501/5a9e30707f8b9a36788c76e5/html5/thumbnails/11.jpg)
![Page 12: Section I Surveying Measurements - Weeblykamalmahmed.weebly.com/uploads/4/6/9/8/46985149/3-_horiz_and_slo… · Section I Surveying Measurements Leveling, horizontal and slope](https://reader030.vdocuments.net/reader030/viewer/2022021501/5a9e30707f8b9a36788c76e5/html5/thumbnails/12.jpg)
Topcon DM-S2 EDM attached to a WILD theodolite
![Page 13: Section I Surveying Measurements - Weeblykamalmahmed.weebly.com/uploads/4/6/9/8/46985149/3-_horiz_and_slo… · Section I Surveying Measurements Leveling, horizontal and slope](https://reader030.vdocuments.net/reader030/viewer/2022021501/5a9e30707f8b9a36788c76e5/html5/thumbnails/13.jpg)
Reflectors (Prisms)
Pole and bipodPrism and sighting target
![Page 14: Section I Surveying Measurements - Weeblykamalmahmed.weebly.com/uploads/4/6/9/8/46985149/3-_horiz_and_slo… · Section I Surveying Measurements Leveling, horizontal and slope](https://reader030.vdocuments.net/reader030/viewer/2022021501/5a9e30707f8b9a36788c76e5/html5/thumbnails/14.jpg)
Laser Distance measuring Devices
![Page 15: Section I Surveying Measurements - Weeblykamalmahmed.weebly.com/uploads/4/6/9/8/46985149/3-_horiz_and_slo… · Section I Surveying Measurements Leveling, horizontal and slope](https://reader030.vdocuments.net/reader030/viewer/2022021501/5a9e30707f8b9a36788c76e5/html5/thumbnails/15.jpg)
Distance Computation
• All measured is phase shift , different signals of wave length: 10 100 1000 10,000 m are sent. Each fraction provides a digit(s).
• (Phase shift / 360)*wave length = non complete cycle length.
• Example: how a distance 3485.123 is measured.
![Page 16: Section I Surveying Measurements - Weeblykamalmahmed.weebly.com/uploads/4/6/9/8/46985149/3-_horiz_and_slo… · Section I Surveying Measurements Leveling, horizontal and slope](https://reader030.vdocuments.net/reader030/viewer/2022021501/5a9e30707f8b9a36788c76e5/html5/thumbnails/16.jpg)
![Page 17: Section I Surveying Measurements - Weeblykamalmahmed.weebly.com/uploads/4/6/9/8/46985149/3-_horiz_and_slo… · Section I Surveying Measurements Leveling, horizontal and slope](https://reader030.vdocuments.net/reader030/viewer/2022021501/5a9e30707f8b9a36788c76e5/html5/thumbnails/17.jpg)
![Page 18: Section I Surveying Measurements - Weeblykamalmahmed.weebly.com/uploads/4/6/9/8/46985149/3-_horiz_and_slo… · Section I Surveying Measurements Leveling, horizontal and slope](https://reader030.vdocuments.net/reader030/viewer/2022021501/5a9e30707f8b9a36788c76e5/html5/thumbnails/18.jpg)
The Idea:To measure the distance between two points (A)
and (B) the EDM on point (A) sends electromagnetic waves. The waves received at (B) are reflected back or resent to (A) by a device on (B).
Electronic Distance MeasurementEDM
•Knowing the speed of electromagnetic waves in the air, the EDM computes the distance by measuring the time difference or the shift of the wave phase angle (will be explained in details later).
![Page 19: Section I Surveying Measurements - Weeblykamalmahmed.weebly.com/uploads/4/6/9/8/46985149/3-_horiz_and_slo… · Section I Surveying Measurements Leveling, horizontal and slope](https://reader030.vdocuments.net/reader030/viewer/2022021501/5a9e30707f8b9a36788c76e5/html5/thumbnails/19.jpg)
![Page 20: Section I Surveying Measurements - Weeblykamalmahmed.weebly.com/uploads/4/6/9/8/46985149/3-_horiz_and_slo… · Section I Surveying Measurements Leveling, horizontal and slope](https://reader030.vdocuments.net/reader030/viewer/2022021501/5a9e30707f8b9a36788c76e5/html5/thumbnails/20.jpg)
Phase Angle φ
0°
90°
180°
270°
Assume that λ = 2 m If φ1 = 80°, it corresponds to a distance = (80/360) * λ = 0.44 mIf φ2 = 135°, it corresponds to a distance = (135/360) * λ = 0.75 mIf φ3 = 240°, it corresponds to a distance = (80/360) * λ = 1.33 m
![Page 21: Section I Surveying Measurements - Weeblykamalmahmed.weebly.com/uploads/4/6/9/8/46985149/3-_horiz_and_slo… · Section I Surveying Measurements Leveling, horizontal and slope](https://reader030.vdocuments.net/reader030/viewer/2022021501/5a9e30707f8b9a36788c76e5/html5/thumbnails/21.jpg)
Reflectors (Prisms)• Are made of high quality glass, excellent reflection
capability.• Accept rotation to right and left, and maybe up and
down, why?? And can be mounted on a tribrach or a pole, why??
• Reflect the energy at the same path it came through. The theory is that if a ray of light hits a mirror and is reflected to hit another mirror and exit the system, the angle between the first and last rays is double the angle between the mirrors. The angle between the mirrors is 90°, three of them resemble three mirrors installed on the walls at the corner of a room, That is why they are called “corner reflectors”
![Page 22: Section I Surveying Measurements - Weeblykamalmahmed.weebly.com/uploads/4/6/9/8/46985149/3-_horiz_and_slo… · Section I Surveying Measurements Leveling, horizontal and slope](https://reader030.vdocuments.net/reader030/viewer/2022021501/5a9e30707f8b9a36788c76e5/html5/thumbnails/22.jpg)
The angle between the rays A and C is double the angle between the two mirrors = 2 *90° = 180°
Notice that the objects will look upside down, notice the box at the tail of the arrow
A
C
B
![Page 23: Section I Surveying Measurements - Weeblykamalmahmed.weebly.com/uploads/4/6/9/8/46985149/3-_horiz_and_slo… · Section I Surveying Measurements Leveling, horizontal and slope](https://reader030.vdocuments.net/reader030/viewer/2022021501/5a9e30707f8b9a36788c76e5/html5/thumbnails/23.jpg)
Prism Constant
Why to consider it?
![Page 24: Section I Surveying Measurements - Weeblykamalmahmed.weebly.com/uploads/4/6/9/8/46985149/3-_horiz_and_slo… · Section I Surveying Measurements Leveling, horizontal and slope](https://reader030.vdocuments.net/reader030/viewer/2022021501/5a9e30707f8b9a36788c76e5/html5/thumbnails/24.jpg)
Aiming at a prism through the telescope of a total station in azoo!
![Page 25: Section I Surveying Measurements - Weeblykamalmahmed.weebly.com/uploads/4/6/9/8/46985149/3-_horiz_and_slo… · Section I Surveying Measurements Leveling, horizontal and slope](https://reader030.vdocuments.net/reader030/viewer/2022021501/5a9e30707f8b9a36788c76e5/html5/thumbnails/25.jpg)
Reflectors (Prisms)
Pole and bipod
Prism and sighting target
Fully rotating prism
![Page 26: Section I Surveying Measurements - Weeblykamalmahmed.weebly.com/uploads/4/6/9/8/46985149/3-_horiz_and_slo… · Section I Surveying Measurements Leveling, horizontal and slope](https://reader030.vdocuments.net/reader030/viewer/2022021501/5a9e30707f8b9a36788c76e5/html5/thumbnails/26.jpg)
u A reflector might include a single prism or a group of prisms
u Reflectors can be a simple reflecting paper-sticker, they are called sheet-prisms, paper prism, or reflective sheeting. Very instrumental in construction sites and deformation monitoring of structures.
u The sighting target might be lower than the prism itself, why???
![Page 27: Section I Surveying Measurements - Weeblykamalmahmed.weebly.com/uploads/4/6/9/8/46985149/3-_horiz_and_slo… · Section I Surveying Measurements Leveling, horizontal and slope](https://reader030.vdocuments.net/reader030/viewer/2022021501/5a9e30707f8b9a36788c76e5/html5/thumbnails/27.jpg)
Remarks
• Accuracy: 3mm, and 3ppm is the most common
• Prismless EDM: up to 100 m, can reach hard places.