civil and environmental engineering applications
TRANSCRIPT
Civil and Environmental Engineering Applications
Geospatial Database: a set of compatible data layers or themes
Relational Linkages
Spatial Attributes
Descriptive Attributes
Water RightLocations
Digital Elevation ModelDigital Elevation Model
Watershed DelineationWatershed Delineation
Raster-Vector Data Model
Raster
Vector
Real World
Map-Based Hydrology and Hydraulics
ArcViewInput Data
DEM
HEC-HMSFlood
discharge
HEC-RASWatersurfaceprofiles
ArcViewFlood
plain maps
CRWR-PrePro
Engineering Design
• Evaluate impact of building a dam– Determine elevation of spillway– Determine aerial extent of reservoir– Delineate contributing watershed– Generate 3D view of reservoir
• Givens– Approximate location of dam– Normal capacity of 50 Mm3 (40,500 acre-ft)– Flood capacity of 100 Mm3 (81,000 acre-ft)
Data Requirements
Elevation Data
1:24,000 DEM (Digital Elevation Model)
1:100,000 paper topographic map
DRG
1:24,000 DRG (Digital Raster Graphic)
Digital Elevation Model
Raster or grid data
Scale1:24,000 (30m)
Digital Raster Graphics
Raster dataScanned topographic map
Scale1:24,000 (30m)
Separate Up/Downgradient
Location of Dam
• Draw polygon to remove area downgradient of dam
• Limits volume calculation to reservoir area
Vector Data
• Used to represent discrete objects
• Point data - monuments, cities
• Line data - roads, rivers
• Vector data - boundaries, soil type
• Composed of distinct nodes & vertices
Generate TIN
TIN - Triangular Irregular Network
•Stores elevations, or other continuous
data, by creating triangles in 3D space
•More efficient data storage
•Estimate volume for cut and fill operations
Separate Up/Downgradient
• Creates two TINs
• Upgradient TIN can be used to determine dam elevation
Determine Dam Elevation
Surface - Area and Volume Statistics
• Elevation
• Area above or below
Dam Elevation
Elevation Volume Area ft m3 m2
224 50,656,491 12,117,735
227.1 100,777.495 18,487,230
Elevations determined by trial and error
Generate Reservoir Image
Map AlgebraAllows user to alter grid data using mathematical tools
1
2 4
35
4
6 5+ =
If ( > 5, 1, 0) = 0
0
1 05
4
6 4
Generate Reservoir Image
If (Elevation < 224, 1, 0)Boolean Image
Generate Reservoir Image
If (Elevation < 227.1, 1, 0)Boolean Image
Normal vs Flood Stage
Estimated reservoirs
can be compared
relative to each
other…..
Normal vs Flood Stage
… merged
with a DRG ...
Normal vs Flood Stage
… or compared
to the entire
watershed
Generating 3D Image
Surface Elevation2D View
3D Image
Vertical Exaggeration Factor = 5
3D Image
Vertical Exaggeration Factor = 5
3D Image
Vertical Exaggeration Factor = 5
GIS for Water QualityGIS for Water Quality
E. coliE. coli 394 cfu/100 mL394 cfu/100 mLNot-to-ExceedNot-to-Exceed
126 cfu/100 mL126 cfu/100 mLGeometric MeanGeometric Mean
400 cfu/100 mL400 cfu/100 mLNot-to-ExceedNot-to-Exceed
200 cfu/100 mL200 cfu/100 mLGeometric MeanGeometric MeanFecal Fecal coliform coliform
Buffalo and Whiteoak BayousBuffalo and Whiteoak Bayous
Landuse in Buffalo and Whiteoak Landuse in Buffalo and Whiteoak BayousBayous
WWTP SamplingWWTP Sampling
Sampled WWTPSampled WWTP
Storm Sewer SamplingStorm Sewer Sampling
EC (MPN/100 mL)0-394
> 394
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Nicholas Negroponte, Founding Director of Nicholas Negroponte, Founding Director of MIT’s Media Lab. MIT’s Media Lab. Being DigitalBeing Digital (1995), p. 6. (1995), p. 6.