superpave orientation local agencies

SUPERPAVE

SUperior PERforming Asphalt PAVEments

Superpave Overview

Major Specification Changes 2006-2015

Specification re-written

Transition to National Testing Standards:

From CTM to AASHTO/ASTM

New Equipment Requirements:

Gyratory

Hamburg Wheel Tracker

Misc

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Superpave Overview

Job Mix Formula Developed by Contractor:

Specification HMA Design Requirements

RAP

Volumetrics

Minor HMA

HMA-L (For Cities and Counties)

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Superpave Overview

Construction Process:

Paving Changes

350 foot windrow maximum

Required use MTV on all RHMA and OGFC mixes

Smoothness

Use of the Inertial Profiler before and after

Use of IRI’s

Pre-Grinding

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Superpave Overview

Construction Process:

Contractor QC Requirements

Cores

Nuclear Gage

State QA Requirements

Same as Contractor

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Superpave Mix Types

2010/2015 Asphalt Concrete

Type A Type B RHMA-G RHMA-O RHMA-HB Minor HMA HMA-L OGFC

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Caltrans Standard Specs

2010/2015

Job Mix Formula Contractor Design/State Verifies Requires Volumetrics at Design, Verification

and during production

Construction 2 Construction Processes

Method Specification

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2010/2015 Section 39 –Organization of Spec

SSP index may be found at:

http://www.dot.ca.gov/hq/esc/oe/construction_standards.html

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Section 39 –Major Changes

Material Requirements

RAP Characterization

Mix Design

Gyratory & Hamburg

Volumetrics

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Why The Change:

Most states use a combination of AASHTO, ASTM and their state test methods. Caltrans switching to national standards provides more uniformity in state to state testing requirements

Many California Test Methods mirror AASHTO test methods. By switching we take advantage and benefit from national research, and lessons learned.

National Testing Standards

AASHTO Test Methods are modified by specification!!!!!!!!

Materials testers must read test methods

Example:

AASHTO T176 allows hand or Idaho shaking

Superpave specification omits these from test.

Testing Methodology Changes

39-1.01D(6) Certifications

39-1.01D(6)(a) General

Laboratories testing aggregate and HMA qualities used to prepare the mix design and JMF must be qualified under AASHTO Materials Reference Laboratory program and the Department's Independent Assurance Program.

Any laboratory touching the aggregate or doing HMA mix design MUST be AMRL accredited. This requirement excludes taking the design samples, which must be taken by a certified test under CT 125

AMRL Laboratory Accreditation Requirements

39-1.01D(6) Certifications

39-1.01D(6)(a) General

Laboratories testing aggregate and HMA qualities used to prepare the mix design and JMF must be qualified under AASHTO Materials Reference Laboratory program and the Department's Independent Assurance Program.

There are no changes to the Caltrans Independent Assurance laboratory certification process under the new specification.

Independent Assurance Laboratory Certification

Requirements

Caltrans Certification for California Test Methods

Tester must be affiliated with a laboratory

Tester must have training documentation

Tester must take and pass a written test

Tester must successfully perform the test for District IA

Caltrans Letter of Proficiency for AASHTO/ASTM Test Methods

Tester must be affiliated with a laboratory

Tester must have training documentation

Tester must take and pass a written test

Tester must successfully perform the test for District IA

A state agency cannot certify testers in test methods it does not own. It can however issue proof that the tester is proficient in the test.

Tester Certification/ Proficiency Requirements

Capital Costs:

Gyratory Compactor $ 46,000 - $ 61,000

Hamburg Wheel Tracker $ 41,000 - $ 81,000

Nuclear Gauge $ 8,000 - $ 15,000

Yearly cost license $ 1,000 - $ 3,000

New Equipment Requirements

HMA & RHMA mix design by Contractor Contractor chooses aggregate size based on total pavement

thickness

OGFC mix design performed by Caltrans

RHMA-G requires a minimum binder content of 7.5% by total weight of material (8.1% by dry weight of aggregate)

Job Mix Formula

RAP may only be used with HMA Type A

25% - 1% at HMA Design, - 3% during producti0n You may not exceed 25% by weight at any time

RAP fractionated on the ⅜-inch sieve. You may use either or both fractions

RAS may only be used with HMA Type A

5% maximum You may not exceed 25% by weight at any time

RAS fractionated on the ⅜-inch sieve

RAP/RAS Requirements

RAP Binder Replacement Maximum replacement

25% for surface course (upper most 0.2 ft)

40% for lower courses

RAS Binder Replacement Maximum replacement

25% for surface course (upper most 0.2 ft)

40% for lower courses

You may use a combination of RAP/RAS

Binder Replacement Requirements

All Mixes except OGFC

Courser Mix

FAA required on all mixes with greater than 10% natural sand

Mixes will require more binder to comply with mix design requirements

HMA Mix Design Requirements

Estimated total material required for Engineer, Contractor, and dispute resolution

Aggregate 450 to 650 pounds

Supplemental fines 20 to 40 pounds

RAP 100 to 200 pounds

HMA 250 to 500 pounds

JMF Material Verification Requirements

JMF Verification Requirements

Typical Verification samples for

CT

JMF Verification Requirements

Think pallets

JMF Verification RequirementsDepartment Acceptance

Type A

39-1.01D(2) Job Mix Formula Verification

For each HMA type and aggregate size specified, the Engineer verifies up to 2 proposed JMF submittals including a JMF adjusted after verification failure. If you submit more than 2 JMFs for each type of HMA and aggregate size, the Engineer deducts $3,000 from payments for each verification exceeding this limit. This deduction does not apply to verifications initiated by the Engineer or if a JMF expires while HMA production is stopped longer than 30 days.

JMF Verification RequirementsDepartment Acceptance

For RHMA-G

39-3.01D(2) Job Mix Formula Verification

If you request, the Engineer verifies RHMA-G quality requirements within 7 days of receiving all verification samples and after the JMF document submittal has been accepted.

Minor HMA

Minor Hot Mix Asphalt JMF submittal required

Used for 1000 (±) tons or less total paving

Aggregate must be treated with LASNo Hamburg or moisture sensitivity testing required

Must use PG64-10 or PG64-16

No QC plan required

No data cores required

HMA-L

City and County HMA Will be SSP format

Design based on TI less than 8

Will not be allowed on State Right of Way

JMF may not be required

Used for low tonnage

Draft Specification under development

Specification vs Method Placement

Method Compaction is specified by conditional statements. If paving does not meet the criteria, then density requirements apply

Each HMA type will have its own specific requirements for actual placement.

Specification vs Method Placement

39-1.03O(2) Method Compaction

Use method compaction for any of the following conditions:

1. HMA pavement thickness shown is less than 0.15 foot

2. Replace asphalt concrete surfacing

3. Leveling courses

4. Areas the Engineer determines conventional compaction and compaction measurement methods are impeded

Quality HMA

QC

QA

Mix Design

Sampling