1 / 41

Mandatory Prepaving Conference

Mandatory Prepaving Conference. Chipseal Construction. Section 37.2 Seal Coats . Keys to Success. Proper surface preparation Use of right asphalt binder, asphaltic/polymer modified emulsion and clean aggregate screenings

domani
Download Presentation

Mandatory Prepaving Conference

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. MandatoryPrepaving Conference Chipseal Construction Section 37.2 Seal Coats

  2. Keys to Success • Proper surface preparation • Use of right asphalt binder, asphaltic/polymer modified emulsion and clean aggregate screenings • Adherence to the project specifications, including traffic control • Check equipment before start • Chip seal in good weather conditions

  3. Topics to be covered • Materials • Equipment • Construction Procedures • Quality Control • Quality Assurance Section 37-2.01A Summary

  4. MATERIALS • Asphalt Binder, Asphaltic Emulsion, Polymer Modified Emulsion (PME) • Screened Aggregates Section 37-2.01A Summary

  5. Equipment • Distributor Trucks • Screened Aggregate Spreaders • Self Propelled Screened Aggregate Spreader • Self Propelled Power Brooms & Vacuums • Pneumatic Tired Rollers • Width ≥ 4’ • Weight ≥ 3000 lbs. per Wheel Section 37-2.03 Equipment

  6. ConstructionProcedures • Proper Surface Preparation • Apply Binder/Asphaltic Emulsion/Polymer Modified Emulsion at Specified Rates & Temperatures • Apply Screened Aggregates at Specified Rates • Roll-as Specified Number of Coverages • Allow Mat to Cure or Cool • Broom Loose Aggregate • Apply a Flush Coat • Open to Traffic After Curing Flush Coat.

  7. Sweeping (before and after) Hot Binder Application Rolling AggregateApplication

  8. Construction-Surface Preparation-Existing Pavement Section 37-2.03D Surface Preparation

  9. Construction-Surface Preparation-Existing Pavement • Cover all exposed facilities before seal coat application. • Reference all covered facilities properly for easy location. • After seal coat application, expose the covered facilities. Section 37-2.03D Surface Preparation

  10. Construction-Surface Preparation-Existing Pavement • Remove all loose and extraneous material by brooming and vacuuming. • Ensure clean, dry surface before applying seal coat. Section 37-2.03D Surface Preparation

  11. Construction –Applying asphaltic Emulsion Section 37-2.03F

  12. Construction –Applying asphaltic Emulsion • In confined areas apply the emulsion with a squeegee, rake or other means authorized by the Engineer. • Cover adjacent areas not intended for sealing with suitable material. • At longitudinal joints, emulsion overlap must be dispersed with squeegees before the application of screenings or rakes. Section 37-2.03F Applying Emulsion

  13. Construction –Applying asphaltic Emulsion • Align longitudinal seal coat joints with designated traffic lanes. Ensure adequate overlap (4”-8”), as directed by engineer. • Plan emulsion application with lane closure requirements, stop an hour before darkness. Section 37-2.03F Applying Emulsion

  14. Construction-EMULSION/BINDER Application Section 37-2.03F(3) &(4)

  15. h Construction – TYPES of EMULSION Overlap Single Overlap Double Overlap Triple Overlap Roadway Surface Section 37-2.03F(3) &(4)

  16. Construction – EMULSION Application

  17. APHALTIC EMULSION APPLICATION RATES • Asphaltic Emulsion or Polymer Modified Asphaltic Emulsion Application (Residual) Rates Section 37-2.03F(3) &(4)

  18. APHALT BINDER APPLICATION RATES • Asphalt (Paint)Binder Application Rates

  19. Construction – SCREENED Aggregate Application Section 37-2.03G (1), (2) &(3)

  20. Construction – SCREENED Aggregate Application Section 37-2.03G (1)(2) &(3)

  21. Screened Aggregates SPREAD RATES Section 37-2.03G (1), (2) &(3)

  22. Construction – SCREENED Aggregate Application • No Traffic on emulsioned areas • Uniform spread rates per specifications over entire lane width • Broom Excess screenings. • Aggregate screenings no roll after dropping. • Aggregate screenings should stop when the spreader stops • Do not spread aggregate screenings ≥ 2500’ ahead of completed initial rolling Section 37-2.03G (1) & (3)

  23. Construction – SCREENED Aggregate Application –BEST PRACTICES • The application always starts with neat straight edges. • The aggregate spreader follows closely behind the distributor truck (50ft.) • Screened aggregates for Polymer Modified Asphaltic Emulsion application are in a damp condition. • The application looks uniform. • Enough trucks are on hand to keep steady supply of chips. • Check for streaks and gate plug. • Screened aggregate sample is secured from the middle of stockpile or chip machine belt for testing.

  24. Construction - Rolling Section 37-2.03H(1)

  25. Construction- Rolling Section 37-2.03H(1)

  26. Construction - Rolling • Correct all ridges, piles, bumps or depressions. • Ensure straight joints, no more than 4” overlap • Longitudinal joints at lane lines • Use pneumatic rollers • Initial rolling with pneumatic roller one coverage • Three coverages of pneumatic roller for final rolling • Broom excess aggregate screenings before opening to traffic Section 37-2.03H(1)

  27. Construction - Curing of Emulsion • Curing time depends on ambient temperature and relative humidity • Emulsion break should begin just after first roller pass • Emulsion curing might take 2 to6 hours, depending upon asphaltic emulsion type & base asphalt

  28. Construction - Brooming Loose Aggregate Section 37-2.03I Seal Coat Maintenance

  29. Seal coat maintenance • Seal coat surfaces must be maintained for 4 consecutive days from the day screened aggregates are applied. • Remove excess screened aggregates from surface by brooming. Exact brooming time & intervals determined by engineer • Use pilot cars to control traffic. • Schedule placement to ensure end of 1 way traffic control an hour before darkness. Section 37-2.0I Seal Coat Maintenance

  30. QualityCONTROL-CONTRACTOR • Polymer Modified Emulsions • Viscosity (AASHTO T59) • Sieve Test (AASHTO T59) • Demulsibility (AASHTO T59) • Torsional Recovery (California Test 332) Section 37-2.0ID (3)

  31. Quality CONTROL-CONTRACTOR • Screened Aggregates • CT 211, Loss at 100 revolutions ≤ 10% • Loss at 500 revolutions ≤ 40% • CT 302, Film Stripping ≤ 25% • C T 227 Cleanliness Value ≥ 80 for Asphaltic Emulsions • C T 227 Cleanliness Value ≥ 86 for PMEs Section 37-2.0ID (3)

  32. Quality CONTROL-CONTRACTOR • Screened Aggregates- CT 202 Gradation-Asphaltic Emulsion Section 37-2.02H (2)

  33. Quality CONTROL-CONTRACTOR • Screened Aggregates- CT 202 Gradation-Polymer Modified Emulsion Section 37-2.02H (3)

  34. Quality CONTROL - Preliminary Responsibilities • Projectreview-Contractor • Alignment, geometrics, shoulders, turnouts • Document review-Joint • Plans & Specifications • Equipment & Material checks-Contractor

  35. Quality Control Pre-Application Inspection (cont.) • Weather requirements • Check the local weather conditions for the proposed paving day. • Ensure that the proposed paving operation can be completed, including the emulsion cure within the favorable weather window. • Reschedule paving operations if rain is predicted within the next 48 hours. Section 37-2.03C Unsuitable Day

  36. Quality Control Pre-Application Inspection • Surface preparation • Equipment inspection • Asphaltic emulsion distributor • Chip spreader • Haul trucks • Rollers- Adequate number of pneumatic rollers • Brooms Section 37-2.01(D) Quality Control

  37. Quality Control Pre-Application Inspection (cont.) • Determining asphaltic emulsion & screened aggregate application rates • Traffic control plan and setup Section 37-2.03F(3) & (4) Application Rates

  38. Quality ASSURANCE - construction Inspection • Asphaltic emulsion application & rates • California Test 339 • Screened aggregate application & rates • Vialit (French)Test ≥ 90% Retention • Traffic control & trucking operation • Rolling

  39. Quality ASSURANCE - construction Inspection • Longitudinal joints – ensure no aggregate buildup • Transverse joints – ensure clean joints, start and stop on construction paper • Brooming to ensure absence of loose aggregate

  40. Quality Control /ASSURANCE Post-Application Inspection • Cleanup • Opening to traffic

  41. Thank you

More Related