Post on 02-Apr-2022
transcript
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Next Generation Sewer
Inspection Techniques:
The TISCA research program:
Technology Innovation for
Sewer Condition Assessment
Jeroen Langeveld, TU Delft/Partners4UrbanWater
Francois Clemens, TU Delft/Deltares
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Sewers and pressure mains in NL
97.300 km gravity sewer, diameter range
200 – 2.500 mm, mainly concrete and PVC
13.000 km pressure main, diameter range
150-1.500 mm, AC, concrete, steel, DI,
PVC
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Gravity sewers: main properties • Hydraulic performance
• Structural performance
• No leakage
• => CCTV dominant inspection technique
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Gravity sewers
• Hydraulic performance
• Structural performance
• No leakage
• => CCTV dominant inspection technique
for decades
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BAA Deformation
BAB Fissure
BAC Break/Collapse
BAD Defective brickwork or masonry
BAE Missing mortar
BAF Surface damage
BAG Intruding connection
BAH Defective connection
BAI Intruding sealing material
BAJ Displaced joint
BAK Lining defect
BAL Defective repair
BAM Weld failure
BAN Porous pipe
BBA Roots
BBB Attached deposits
BBC Settled deposits
BBD Ingress of soil
BBE Other obstacles
BBF Infiltration
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Pressure mains
• Limited number failures/operator/year
• Average 1 failure/100 km/year (6 for
drinking water mains)
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Inspection of pressure mains?
• No ‘one size fits all’ inspection technology
available (same for gravity sewers)
• Pressure mains not designed for O&M:
– No redundancy
– No access for inspection equipment, smart
pigs
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Inspection of gravity sewers and
pressure mains
Both require inspection data on:
I. Hydraulic performance
II. Structural stability
III. Leakage: infiltration or exfiltration
=> As one-size fits-all doesn’t work, we
need to move towards the next generation
sewer inspection techniques
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TISCA Program
• 5 projects:
– FEM failure model for deteriorated concrete
pipes including soil
– Automatic pattern recognition of CCTV
footage
– In sewer drone/multi-sensor platform
– Flying drone with IR camera, ground
penetrating radar
– Geo-electric leak detection
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Geo-electrical methods
I. Electrical Resistivity Tomography (ERT)
II. Self Potential measurements (SP).