Topographic Surveys

From our offices in the London, the South East, and the South West we offer a wide range of topographic surveys to cater for the many needs of our clients.

  • General Surveys

    • Topographic surveys for planning and construction
    • UAV photogrammetric orthomosaic & mapping
    • Geodetic and topographical road alignment surveys using non-contact methods to restrict traffic disruption
    • Building alignment and control
    • Precise construction check surveys
    • Volumetric, hydrographic and drainage surveys
    • Pipe run and schematic surveys
    • Tree tagging and scheduling for management surveys
    • Feasibility surveys
    • River basin cross section measurement
    • Pre and post fill volume surveys
  • Underground Service Survey

    We provide a full suite of services to provide greater confidence to clients in underground utility detection, maintenance, and replacement.

    • Electronic detection of buried services
    • Ground penetrating radar
    • Remote visual surveys
    • Inspection chamber records
    • Interpretation of historical data

    We now also work to the widely recognised PAS128 industry standard. This is a robust methodology for delivering utility surveys in the UK. It focuses on levels of accuracy – referred to as Survey Category Types – that you can specify when requiring a PAS 128 compliant underground utility survey.

    There are four Survey Category Types ranging from D – A:

    PAS 128 Survey Category Type D

    Underground utility plotted from utility record data only (not detected by geophysical methods).

    PAS 128 Survey Category Type C

    Underground utility plotted from utility record data only, but with site reconnaissance to match utility record with physical utility street furniture as a best fit.

    PAS 128 Survey Category Type B

    Utility detected by geophysical methods (single or multiple) to obtain a horizontal position and/or vertical position. (Depth) For the positional accuracy of each QL-B sub category please refer to the Accuracy Diagram.

    PAS 128 Survey Category Type A

    Utility verified and positioned by physical identification. This may be by strategically positioned vacuum excavation, hand dug trail pitting or by visual inspection within a utility chamber.

  • 3D Capture

    What is 3D capture?

    3D capture refers to the mass collection of spatial data beyond the tradition wire frame formats popular with building surveys. Spatial data can include:

    • 3D position
    • Colour
    • Change over time
    • Surface data – digital surface or terrain modelling

    How is 3D data captured?

    3D capture is a growing field with new technologies coming forward constantly. Currently, we offer the following methods:

    • Colour laser scanners
    • UAV and land based photogrammetry
    • Vehicle based terrain capture
    • High altitude LiDAR and photogrammetry
    • Satellite LiDAR and photogrammetry

    What are the benefits of 3D capture?

    3D capture allows our surveyors to collect huge amounts of data in short periods of time from a remote position. The benefits include:

    • Increased speed of acquisition
    • Dense data 
    • Colour & photo realistic data
    • Office processing
    • Flexible/changeable deliverable since most data is captured on site
    • Remote sensing reduces access issues

    What format is 3D data delivered?

    • 3D wireframe models
    • 3D rendered models
    • Point clouds
    • Animated videos
    • Survey4BIM 3D Revit models compliant with PAS 1192-2
  • Structural Monitoring

    Why do you carry out structural monitoring?

    Before we propose any sort of structural monitoring we work with the client to understand:

    • What is the structure
    • What are the load conditions
    • Are there any proposed changes to the load conditions
    • Are there any load conditions not planned for but carrying significant risk (known-unknowns

    If any of the above test the structure beyond its design criteria, structural monitoring should be considered.

    How do you do structural monitoring?

    There are three main types of spatial monitoring:

    1. 2D planar sections
    2. 3D point monitoring
    3. Surface monitoring

    Taking into account the above type we use:

    • Digital level
    • Robotic total station
    • Scanner
    • UAV photogrammetry
    • Inclinometer
    • Liquid levelling system
    • Bespoke combination

    I addition to spatial monitoring we provide various other systems for testing against:

    • Vibration
    • Heat
    • Moisture

    What do you test against?

    All data is fed into a database and tested against these thresholds:

    • Green – within normal conditions
    • Amber – consultation and potential action required
    • Red – Stop work and take immediate action

    What needs structural monitoring?

    Use cases might include:

    • Dock walls, gates & structures
    • Diaphragm walls
    • Running rail twist and cant
    • Coastal erosion
    • Rock face monitoring
    • Stock pile analysis

    What is automated monitoring?

    Automated monitoring is where equipment is setup and left on site in a secure and reliable manner. Most systems can be automated and generally, it leads to a more cost effective life span.

    Data is reported wirelessly and presented at regular intervals through either a web interface or email files.

  • Geodetic Surveys

    • GNSS geodetic surveys
    • Establishing control
    • Historical checks
  • Measured Building Survey

    What is a measured building survey?

    Measured building surveys are an accurate plan of all aspects of a building including structure, internal dividers, external fittings and M&E services.

    What information is in a measured building survey?

    Information collected for a building survey can include:

    • Floor plans
    • Ceiling plans
    • Roof plans
    • Elevations
    • Sections
    • Mechanical and electrical services

    How is a measured building survey carried out?

    Paul Fassam Geomatics always invests in the latest technology to reduce the time on site and improve deliverables. The technology we use to deliver cost effective building surveys includes:

    • Total stations
    • Scanners
    • Internal photogrammetry
    • 360 Photogrammetry  globes for client visualisation
    • UAV aerial photogrammetry
    • Disto and tape measure

    What data format is a building survey?

    Depending on the client we produce a variety of outputs including:

    • 2D floor plans
    • 3D wire frames
    • 3D rendered structure
    • Point clouds from scanning and photogrammetry
    • Otho-rectified photos with 2D wireframe overlay

    All of the above are BIM ready where necessary.

  • Hydrographic Surveys

    • River bed profiles
    • Pre & post dredging analysis
    • Silt monitoring
    • Construction & design surveys
    • Flood plain analysis
    • Channel modelling
    • Reservoir volume calculation

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