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Joseph Peterson, Caltrans
Office of Roadway Material Testing
Quality is not act. It is a habit.
~Aristotle
Reality is not Reality; Reality is what we perceive Reality to be.
Quality Control
What is Quality Control: QC is a procedure or set of procedures intended to ensure that a manufactured product or performed
service adheres to a defined set of quality criteria or meets the requirements of the client or customer.
Quality Assurance
What is Quality Assurance: QA is defined as a procedure or set of procedures intended to ensure that a product or service under
development (before work is complete, as opposed to afterwards) meets specified requirements.
* Read the Specification * Traffic Control Plan * Weather Restrictions * Allowable Placement Temperature * Ambient-‐Surface
* Materials Requirements * Placement Requirements * Sweeping Requirements * Temporary Delineation
KEYS TO GOOD INSPECTION
* Inspector Should Have: * Mix Design * Emulsion Type * Starting Application Rate * Aggregate Gradation * Starting Application Rate * Additives/Fillers
KEYS TO GOOD INSPECTION
* Inspector Should Have: * Emulsion
Certificate of Compliance
KEYS TO GOOD INSPECTION
Seal Coats Will Not * Fix Pot Holes * Bridge Cracks>1/4” * Smooth Out Road * Add Structural Strength
Have Reasonable Expectations
What’s Not Wrong
Which is ready for a chip or slurry?
Step 1 Pre-Application Proper Roadway Preparation
* NO Drainage Problems * Pavement Distress Repaired * Cracks Sealed
Poor Candidate or Prep Work Results in…
Or
* Distributer Truck * Spray Bar Height * Nozzles Free of Clogs * Correct Pressure * Double or Triple Overlap * Spray Rate Calibration * Temperature
Step 2 Equipment Inspection
Equipment Inspection
Triple Overlap
GOOD…
Equipment Inspection
Equipment Inspection
BAD…
Why
Improper Shot Rate
Bad Overlap Inadequate Chips Rutting Other Combination of ?
Equipment Inspection
* Chipper * Gate Control Settings * Scalping Screen in Good Condition * Uniformity Across Chipper Head * Application Rate Calibration
Equipment Inspection
Uniformity!!!!!!!!!!!!!!!
Why
Improper Shot Rate
Bad Emulsion Inadequate Chips Rutting Other Combination of ?
Equipment Inspection
* Pneumatic Rollers * Tire Pressure Uniform * Tires smooth
* Broom * Uniform Bristles * Vertical Adjustment
* Haul Trucks * Free of Trash
* Stockpiles * Contamination * Moisture * Grading * Cleanness * Environmental
Step 3 Materials Inspection/Testing
txdot
* Binder Testing * Sample from Distributor Truck * Sample from Nurse Truck * Proper handling is key to
accurate test results * Timely testing
* On-site emulsion – simple sieve test
Step 3 Materials Inspection/Testing
Step 4 Construction Inspection
Roll Chip
Spray
Sweep
Sweep Again
Construction Inspection
NOTE DISTANCE
Chipper always within 100 feet of Distributer
* Start/Stop Application on Building Paper * Chipper Within 100’ of Distributer * Chipper Speed =NO rolling Chips * Application Appears Uniform * Rollers Tight to Chipper, Speed 7mph max
Construction Inspection
* Visual Chip Embedment (50%-‐70%) * Random Verification of Spread Rates * Emulsion * Aggregate * On-‐Site sieve test
Construction Inspection
* Proper &Timely Sweeping * Light Broom within 24-‐36 hours of Application * Intermediate Brooming as Required * Final Brooming Typically Within 5 days
Construction Inspection
Construction Inspection
Poor Workmanship Good Workmanship
Construction Inspection
Poor Workmanship
Construction Inspection
Trucks on Emulsion?
Out of Spec Material?
Construction Inspection
Inadequate/Uneven Aggregate Coverage or Precoating Issues
The Finished Product
* California Chip Seal Association * http://www.chipseal.org/
* Maintenance Technical Advisory Guide (MTAG) * http://www.dot.ca.gov/hq/maint/mtag/ch5_chip_seals.pdf * FHWA Construction Inspection Checklist #02 Chip Seal Application * http://www.bwa.dot.gov/pavement/preservation/ppcl02.pdf * California Pavement Preservation Center * http://www.csuchico.edu/cp2c/index.shtml
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