digital photos and 3d models for documentation and … · 2016. 3. 25. · digital photos and 3d...

Digital Photos and 3D Models for Documentation and Visualization of Failed Slopes

Jeffrey R. Keaton - AMEC E&I, Inc., Los Angeles, CA

John C. Mason - AMEC E&I, Inc., Knoxville, TN

Carl D. Tockstein - AMEC E&I, Inc., Knoxville, TN

Stanley L. Hite - AMEC E&I, Inc., Richmond, VA

Chattanooga, TNAugust 4, 2011

2Chattanooga, TN, Aug 4, 201111th Annual Technical Forum – Geohazards Impacting Transportation in the Appalachian Region

Methods and imagesConventional and special aerial photos Aerial and ground-based laser scanningGround-based stereo photos Terrestrial photogrammetry For visualization For measurements (ShapeMetriX3D – 3GSM)Calibrated camera and lens

Limitations, of course

Documentation and Visualization


Stereo Pairs of Aerial Photos


Low-Sun Angle Illumination


Aerial Lidar – Synthetic Low-Sun Illumination

Bluegill Landslide, Idaho

Data from Nancy GlennIdaho State University Department of Geology


3D Laser Scanning

Siefko Slob, ITCDelft, The Netherlands

Rock Slope in Spain(Optec Scanner)


3D Laser Scanning

Siefko Slob, ITCDelft, The Netherlands

Cluster Analysis using Matlab Script


3D Model for Visualization


Terrestrial Photogrammetry - Parallax

D

B ≈ D5

D8to


Stereo Pair with Range Pole

Range Pole

Right Image

Left Image

Bull's-eyeLevel

2.35 m

Azimuth (x,y,z)

Stereo Model

- Handheld camera- Calibrated digital

camera & lens- Range reference- Vertical reference- North reference- Spatial reference


Range Pole and Ground Target


Rock Structure Measured with ShapeMetriX3D

GEOTECHNICAL PARAMETERSPositions (X,Y,Z) [m, ft]Distances, lengths [m, ft]Areas [m2, ft2]Orientations from faces [°/°]Orientations from traces [°/°]Bridges between tracesFree grouping to setsSpacing, StereogramsExport directly into CAD, MS Excel


Rock Structure Measured with ShapeMetriX3D

Geologist's mapping tool for assessing joint setsAccess difficulty eased and safety enhanced


Stereographic Projection


Basic Model – Detailed Model

Distinctive points (red) identified in this model become ...

Basic model normalized with range pole


Basic Model – Detailed Model

Detailed model normalized with distinctive points from basic model

... reference pointsin this detailed model.


Bedding Plane Roughness

Export modelsurface for usein other software(GIS, AutoCAD)

Use profile toolin ShapeMetriX3Dand export values


Model Point Density

48,985 pts

543,746 pts

632,852 pts



142,362 points



JRC > 20

JRC = 15.5

Hoek, 2004


Rock Block Dimensions Volume


Rock Block Dimensions


Slope Profile


Westbound I-24 near Monteagle, TN

Model Gap

Rock Fall Release Area



Model Gap



Model Gap

Scale in Feet

Ele

vatio

n in

Fee

t


Vertical Section from I-24 near Monteagle, TN

Stereo photos with calibrated camera Surveyed range pole & ground targets 3D model (ShapeMetriX3D) Vertical section tool (ShapeMetriX3D) Extract x,y data (comma-separated) Read data in spreadsheet (Excel) Plot to scale (1”=20’ in SigmaPlot) Time requirements (after field work) Build 3D model = 20 minutesMake vertical section = 15 secondsRead in Excel = 30 seconds Plot in SigmaPlot = 5 minutes

115-ft-high slope nearly

ready for CRSP

or Rocfall


Stereo Model of 1959 Aerial Photos

Landslide terrain in Southern California


Limitations

What you see is what you can model Vegetation and other obstructions Blowing leaves and dust; snowHigh-contrast patchy sun and shadowDraped wire mesh in sun with rock in shadow

Accuracy depends on the number of pixels in an areaOblique view angle gives nonlinear range of accuracy Small features must be close to the camera

The software works with pixel clustersUniform surfaces, like painted walls, have non-unique pixels

Digital Photos and 3D Models for Documentation and Visualization of Failed Slopes

Jeffrey R. Keaton - AMEC E&I, Inc., Los Angeles, CA

John C. Mason - AMEC E&I, Inc., Knoxville, TN

Carl D. Tockstein - AMEC E&I, Inc., Knoxville, TN

Stanley L. Hite - AMEC E&I, Inc., Richmond, VA

Chattanooga, TNAugust 4, 2011

digital photos and 3d models for documentation and … · 2016. 3. 25. · digital photos and 3d...

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