Engineering / Surveying– 3D map is prepared using CAD that depicts all features and contour lines....
Transcript of Engineering / Surveying– 3D map is prepared using CAD that depicts all features and contour lines....
Engineering / Surveying
Anas Malkawi
Objective
• This session provides information on how to read engineering/construction plans and the techniques and principles of surveying. Possible career fields will be demonstrated
Engineering
• Application of scientific, economic, social, and practical knowledge in order to design, build, and maintain structures, machines, devices, systems, materials and processes.
• Using mathematics and science to solve everyday problems
Surveying
• Technique, profession, and science of accurately determining the 3D position of points and the distances and angles between them.
• Notable Surveyors – George Washington
– Thomas Jefferson
– Abraham Lincoln
– Meriwether Lewis & William Clark
– Charles Mason & Jeremiah Dixon
Public Works
• Infrastructure projects • Financed and constructed by the government • Examples:
– Public services (Utilities/Pipelines): • Water supply • Sewage • Electrical • Gas
– Transportation • Roads • Bridges • Railroads • Ports • Airports
– Public spaces / facilities • Public squares • Parks • Beaches • Schools • hospitals
Engineering Plans
• Scale
• Layout of drawings
– Plan
– Profile
– Cross Section
• Line weight and line formatting
• Elevations
• Details
Scale
• Ratio of a distance on the map/plan to the corresponding distance on the ground.
• Examples
– Scale bar
– Scale ratio
Layout of drawings
Detail Drawings
Line weight and formatting
• Size/type of line
• Size/type of font
• layering
Facility layout
Surveying tools
• Traditional – Compass – Chain – Transit – Theodolite
• Contemporary – Total Station – Level – Computer Aided Design (CAD)
• Advanced – GNSS / GPS – Laser Scanner – 3D CAD – Geographic Information System (GIS)
Traditional Tools
• Compass
• Chain
• Transit
• Theodolite
• Drafting tools (T-Square, protractor, triangle, …etc)
Contemporary Tools
• Total Station
• Level
• Computer Aided Drafting
Advanced Tools
• GNSS / GPS
• Laser Scanner
• 3D CAD
• Geographic Information System (GIS)
• GPS Machine Control
GIS in Public Works
• Location of assets and facilities
• Navigation to assets
• Attributes (pipe diameter, length, depth, material, …etc)
GNSS / GPS
Surveying methods
• Basic – Pacing – Compass – Measuring tape / wheel
• Conventional / Traditional – Traverse – Leveling
• Contemporary / Advanced – GNSS / GPS – Remote Sensing
Public Works Surveys
• Topographic Survey: gather XYZ data about the natural and man-made features of the land. – 3D map is prepared using CAD that depicts all features and contour lines.
• Construction stake out: locating and marking reference points that will guide the construction of new structures (buildings, roads, pipe bends, appurtenances, …etc.) based on the CAD design
• As-built Survey: a survey that verifies that a constructed project has been
built in accordance with design specifications. – Adjusts plans to existing “as-built” conditions – Prepare a site plan for a facility that we never had plans for
• Boundary/Property Survey: – Research property records / Plats – Check the accuracy of a property line
• Setting or restoring monuments/markers at corners of the parcel
Slope
• Vertical change in a line
• Rise / Run
• 100’ of 10” RCP with a 1’ invert elevation = 1% slope
Levelling
Levelling
• Levelling: measurement of geodetic height using an optical instrument and a level staff or rod having a numbered scale.
• Finding the elevation of a given point with respect to the given or assumed Datum.
• Benchmarks: a point with a precisely known relationship to the level datum of the area (typically MSL).
Levelling
• Benchmark examples:
– Bronze disc set in concrete
– Rebar driven to refusal
– Railroad spike on a telephone pole
– Square cut in concrete on a bridge
– Concrete property monument
Levelling
Levelling
Levelling
Levelling
Levelling
HI = BS reading + Last Elevation New Elevation = HI – FS reading
Pace Count
• Used to measure distance by counting the number of paces between two points
• Average pace count (feet/pace)
– Usually between 2.3-3.3
• If my pace count is 3, how many paces will it take to travel 300 feet?
300/3 = 100 paces
Pace Count
• Exercise in the hallway/outside
Measuring / Redundancy
• The more observations the better to get a more precise answer
• Take mean of measurements
• If asked to get a distance from manhole to manhole, take several measurements 50.3’, 49.5’, 49.9’, 50.1’
Mean = sum of observations
number of observations
Mean = 50.3+49.5+49.9+50.1 = 49.95’
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Engineering Team
• Director of Engineering
• Chief Engineer / Program Manager
• Project Manager
• Utilities Engineer (Civil / Environmental)
• Planner
• Construction Inspector
• Engineering Technician
• GIS/CAD Technician
Surveying Team
• Project Manager: QA/QC and legal responsibility. Public relations.
• Survey Crew Chief: field operations
• Survey Technician: Data computations / drafting
• Instrument Operator: Data collection
• Rodman: carry prism/rod and
Surveyor Duties
• Research property records
• Establish grades for a new pipeline
• Check the accuracy of a property line
• Licensed Surveyors are licensed by the state to be legally responsible for information collected by a survey party.