Types of Surveys U2 PDF

Types Of Surveys TCS110 - Surveying Level 1 Unit 2  TCS110 - Surveying Level 1 Topics. Classification of surveys - Primary Classification and Secondary classification Other types of survey - Topographica...

Types Of Surveys TCS110 - Surveying Level 1 Unit 2  TCS110 - Surveying Level 1 Topics. Classification of surveys - Primary Classification and Secondary classification Other types of survey - Topographical Surveys - Hydrographic Surveys - Cadastral Surveys - Asbuilt Surveys - Construction Survey - Equiptment Safty - Application of the types of survey Types of Surveying Classification A. Primary Classification or Primary Division B. Secondary Classification or Division  Primary Classification of Survey 1. Plane surveying 2. Geodetic surveying 1. Plane Surveying The shape of the earth is spherical. Thus the surface is obviously curved. But in plane surveying the curvature of earth is not taken into account. This is because plane surveying is carried out over a small area, so the surface of the earth is considered as a plane. The degree of accuracy required in this type of surveying is completely low. Plane surveying is done on an area of less than 250 sq.km Plane Surveying Plane Surveying Surface Plane Surveying  Primary Classification of Survey 2. Geodetic surveying In geodetic surveying the curvature of the earth is taken into consideration. It is extended over a large area greater than 250 sq.km. The line joining any two points considered as a curved line. Very refined methods and instruments are used in this type of surveying. In this method very high precision or accuracy is required  Geodetic Surveying Geodesy (Geodesist) The science of accurately measuring and understanding the earth’s geometric shape, its orientation and gravity field.  Types of Surveying Surface Examples of Ellipsoids WGS84 (World Geodetic System) GRS80 (Geodetic Reference System)  Secondary Classification of Survey Survey can be classified on different bases: 1. Based on instrument: Chain Survey Compass survey Plane Table survey Theodolite survey Tacheometric Survey Photographic survey 2. Based on methods: Triangulation Survey Traverse Survey. 3. Based on Objects: Geological survey Mine survey Archeological Survey Military survey 4. Based on nature of field Land Survey Sea Survey Marine survey Astronomical survey.  Other Types of Surveys Topographic Hydrographic Property (Cadastral Survey) Final (As-built) Aerial Construction (Engineering) Route  Topographic Surveys Topographic surveying is the process of determining the positions, on the earth’s surface, of the natural, and artificial features of a given locality and of determining the configuration of the terrain. Planimetry – location of features Topography – configuration of the ground Both produce a topographic map which shows the true distance between objects & their elevations above a given datum Topos can be done by field methods, or by photogrammetric methods. (Photo also requires some field work) Topo map is 1st step in a construction project.  Topographic Surveys  Collecting data and preparing maps showing the locations of natural man-made features and elevations of points of the ground for multiple uses. TOPOGRAPHIC SURVEYS HYDROGRAPHIC SURVEYS The science of measuring and depiction those parameters necessary to describe the precise nature and configuration of the seabed, its geographical relationship to the landmass, and the characteristics and dynamics of the sea. Usually shorelines, water depths and marine features are shown on hydrographic map or electronic chart. Hydrographic Surveys Hydrographic map of water depth (Bathymetric Map) RMS Rhone 1867 shipwreck Hydrographic Surveys  Property Surveys (Cadastral Surveys) The discipline of land surveying that is related to the laws of the land ownership and the definition of existing property boundaries or the layout of new property boundaries.  Property Surveys (Cadastral Surveys) General Boundaries: A physical feature (hedge, wall, fence, ect.) is accepted as the boundary and mapped. Fixed Boundaries: Boundaries are defined as invisible lines with boundary marks placed at the corners. Property Surveys (Cadastral Surveys) General Boundaries Property Surveys (Cadastral Surveys) Fixed Boundsaries  Final Surveys (As-built) This is a survey that may show variations from original plans to what is actually built. As-builts surveys are required by agencies to prove the location of a structure at a point in time and to check that construction has proceeded according to the design plan. Final Surveys (As-built) As-built survey using Laser Scanning  Photogrammetry  Photogrammetry– mapping utilizing data obtained by camera or other sensors carried in airplanes or satellites.  Aerial Surveys  A survey method of collecting aerial photography and aerial imagery by using airplanes, helicopters or UAVs. It includes the use of digital cameras, multispectral scanners, LiDAR, and radar.  Aerial Surveys Photography Lidar Imagery  Construction Surveys  Also known as a Site Layout Survey, is the process of interpreting construction plans and marking the location of proposed new structures such as roads or buildings. This survey is performed to ensure a project is built according to engineering design plans. Construction Surveys  Route Surveys Comprised of all survey operations required for design and construction of engineering works such as highways, pipelines, canals, or railroads.  Route Surveys Functional planning and route selection usually involve the use of aerial imagery, satellite imagery, and ground surveys as well as the analysis of existing plans and maps. Factors that influence Route selection: Social Impact Environment Terrain Financial Impact Route Surveys Route Surveys  Types of Surveying Surface Plane Survey Survey Grid Reference Grid lines on a map divided into squares defining the coordinate system using Eastings (x) and Northings (y). Used to accurately pinpoint your location on a survey map. Limited in size so that no serious errors will accumulate when the curvature of the earth is ignored. All countries have adopted a grid system that best suits their needs.  Types of Surveying Surface Plane Survey Survey Grid Reference  Types of Surveying Surface Survey Grid Reference Plane Survey BUILDING TREES Point Easting Northing Point Easting Northing A 90 15 J 60 30 B 60 45 K 90 105 C 75 60 D 60 75 E 75 90 F 90 75 G 105 90 H 135 60 I 90 15 Map Projections The Relationship between the Curvature of the Earth and a flat surface https://www.youtube.com/watch?v=kIID5FDi2JQ  Horizontal & Vertical Reference Survey Geographic Reference Define reference as the surface of earth. Latitude: East/West //equator. - Max angle 90o north or south. Longitude (Meridians): North/South converge at poles & max angle =. 180 degree east or west from the plane of 0o longitude Greenwich. - used in geodetic not plane survey. - Plane survey use coordinates grid system. Survey Grid Reference States and provinces have adopted a grid system best suited to their needs. - Limited in size: no serious error due to curvatures. - Easy to use (plane geometry & trigonometry). - Common datum for x & y dimensions. - Easy to translate to geodetic survey. Survey Vertical reference Vertical dimension can be referenced to any datum. - Mostly used datum is mean sea level MSL = 0.000 ft. - Benchmarks permanent points whose elevation has been precisely determined  Horizontal & Vertical Reference Horizontal Reference: Provides a reference frame for coordinates on earth using precise X, Y locations. Vertical Reference: Elevation to which heights of various points are referenced.  Horizontal & Vertical Reference Triangulation Station (Trig) Survey Control Network Also known as a Geodetic Control Network is a network of triangles which are measured using surveying techniques.  Horizontal & Vertical Reference Primary Control Points Survey Control Network These are the Triangulation Network Stations Secondary Control Points These are reference to the primary control stations Horizontal & Vertical Reference Bench Marks A permanent mark establish at a known elevation that is used as the basis for measuring the elevation of other topographic points