Post on 20-Jan-2022
transcript
Data Specifications/ Contract Requirements
- Features to be surveyed
- Feature Presentation
- Relief Presentation (e.g. contour)
- Symbology
- Attribute Data (e.g. Pipe Dimension)
- Format of Product
Things to be Considered for Topographical Surveying
Common Survey Methods for Topographical Surveying
Traditional Methods
Total Station/ Laser Scanner
Aerial Photogrammetry
RTK GPS
Airborne Lidar
Common Survey Methods for Topographical Surveying
New Methods
- Overcome survey limitations
- True 3D topographic Presentation
- Full Coverage of Topographic features
- Reality Presentation
- Integrated Solutions
Imaging Survey System (Close Range Photogrammetry + Total Station +GPS)
UAV Survey System (Photogrammetry + Lidar + INS +GPS) Mobile Mapping System
(Photogrammetry + Scanner + INS +GPS)
Things you must know…
- Factors affecting design of topo survey
- Features of topo survey
- Choice of instrument
- Mapping specification in HK
- Types of maps in HK
- Basic working principles of different instruments
- Coordinate systems in HK
What is Utility Surveying?
… the process of identifying and labeling public utility mains that are underground. Utility Surveying includes lines for telecommunication, electricity distribution, natural gas, cable television, fiber optics, traffic lights, street lights, storm drains, water mains, and waste water pipes.
This profession strives to provide solutions that help to solve a range of underground utility problems at different stages, from (1) initial systems and design, then (2) intermediate surveying and construction, and (3) long term monitoring and maintenance, data, operational and asset management.
… they can be divided to two major types ... for the layout of new systems and for locating existing systems … both above or below ground.
What is Utility Surveying?
Utility Survey (Alignment and Level)
Condition Survey (Condition of Utility)
Utility Information Management
(Information System)
Underground Inspection (e.g. Void/ leakage)
Utility Asset Management (Long-term Maintenance)
Things to be Considered for Utility Surveying
Legal Requirement
Occupation
(License by LandsD)
Operation
Excavation
(XP by HyD/LandsD)
Cap. 406 / Electricity Ordinance
Cap. 51 / Gas Safety Ordinance
Cap. 102 / Waterworks Ordinance
Cap. 106 / Telecom. Ordinance
Cap. 28
Land (Miscellaneous Provisions)
Ordinance
Occupation of
unleased land
Control of excavations
in unleased land Protection
Measures
Equipment for Utility Surveying
Pipe Cable Locator (Electromagnetic Properties of
Electric Current)
Ground Penetration Radar (Detect Reflection of Microwave Band
Signal)
Equipment for Utility Surveying
CCTV Inspection (Video Inspection)
Leak Noise Detector (Correlation of Soundwave)
Total Station/ Laser Scanner