CVEN 254: Introduction to Surveying

CVEN 254: Introduction to Surveying

Learning Outcomes

  • In this course, you will learn:

    • Basic surveying terms, principles, and calculations.

    • How to operate a surveyor’s level and rod.

    • How to operate a surveyor’s total station and prism.

What is Surveying?

  • Definition:

    • Surveying is defined as the measurement of dimensional relationships, including:

    • Horizontal distances

    • Elevations

    • Directions

    • Angles

    • Purpose:

    • Data is used for locating property boundaries, construction layout, engineering design, and mapmaking.

Applications of Surveying

  • Surveying may be used to:

    • Locate ground features for map or planning, facilitating geographic assessments.

    • Locate design features shown on maps or plans in the field to ensure accurate implementation.

Types of Surveying

  • Plane Surveying:

    • Characterization:

    • The earth's surface is treated as a plane.

    • Only x and y dimensions are considered in a flat context.

    • All z dimensions are referenced to the mean surface of the earth or its reference ellipsoid.

    • Application:

    • Most common in engineering and property surveys.

  • Geodetic Surveying:

    • Characterization:

    • The earth's surface is treated as an ellipsoid.

    • X and y dimensions account for the earth’s curvature.

    • All z dimensions are similarly referenced to the earth’s reference ellipsoid.

    • Historical Context:

    • Historically significant for determining national boundaries and establishing control networks.

    • Modern Relevance:

    • Surveys using Global Positioning Systems (GPS) fall under this category.

Differences Between Geodetic and Plane Surveying

Plane Surveying

Geodetic Surveying

Earth is a plane surface.

Earth is a curved surface.

Curvature of the earth is ignored.

Curvature is taken into account.

Lines between stations treated as straight lines.

Lines are curved due to earth’s shape.

Triangles formed are considered planar.

Triangles are spherical in nature.

Suitable for areas less than 250 km².

Suitable for larger areas greater than 250 km².

Classes of Surveys

  • Control Surveys:

    • Used to establish reference points for various purposes, including construction.

    • Horizontal Controls:

    • Typically tied to property corners or roadway centerlines.

    • Vertical Control Points:

    • Series of benchmarks indicating elevations above a datum (e.g., mean surface of earth).

  • Preliminary Surveys:

    • Gather geospatial data (distances, positions, angles) to identify physical features for plotting on maps.

    • May include the determination of site elevations.

  • Layout Surveys:

    • Involve marking features on site using various tools (stakes, flags, etc.) from map designs.

    • Encompasses both property and engineering/construction surveys.

Surveying Projects

  • Different types of surveying projects include:

    • Topographic Survey

    • Hydrographic Surveys

    • Route Surveys

    • Property Surveys

    • Final or As-Built Surveys

    • Aerial Surveys

    • Construction Surveys

Location Methods

  • Discusses the methodologies for locating features on the ground, including:

    • Measurements of horizontal distance, slope angle, and vertical distance.

  • Illustrated methods include:

    • Point A to Point B measurements in either horizontal, vertical, or slope contexts.

Measurement Definitions and Equivalencies

Measurement Type

Equivalence

1 mile

5,280 feet

1 kilometer

0.62137 miles (approx.)

1 acre

43,560 ft²

1 hectare

10,000 m²

1 revolution

360°

  • Angular Measurements:

    • 1 degree = 60' (minutes)

    • 1 minute = 60" (seconds)

  • Note on foot-to-metric conversions:

    • 1 ft = 0.3048 m (exactly)

    • Historical context includes prior definitions affecting US measurement standards.

Accuracy and Precision

  • Accuracy:

    • Relates to how close a measurement is to the true value.

  • Precision:

    • Refers to the refinement of the measuring process and the repeatability of a measurement.

Homework Assignment

  • Create one or two slides to describe a piece of surveying equipment, including photographs.

  • Research can cover either historical or modern equipment.