Skip to contentUnited States Department of Transportation - Federal Highway Administration FHWA Home
Research Home   |   Pavements Home
Report
This report is an archived publication and may contain dated technical, contact, and link information
Publication Number: FHWA-RD-07-052
Date: September 2007

Long Term Pavement Performance Project Laboratory Materials Testing and Handling Guide

Protocol P22
Test Method for Penetrationof Extracted Asphalt Cement At 77 °F and 115 °F (AE02)

This LTPP protocol covers the determination of the penetration of extracted asphalt cements at 77°F (25°C) and 115°F (46°C).

This test shall be carried out in accordance with AASHTO T49-89 with the exception of some of the sections of the reference standard which have been modified as presented below. In all other remaining sections, AASHTO T49-89 shall be followed as written. The test will be carried out on asphalt cement specimens extracted from AC core and block samples, as well as uncompacted samples of both virgin and recycled aggregate mixtures recovered from test sections included in the LTPP experiments. The asphalt cement shall be recovered from the AC cores and asphalt-aggregate mixtures by the Abson method specified in LTPP Protocol P21.

1. SCOPE

1.1 This method describes a procedure for determining the penetration of extracted asphalt cement at two temperatures (77°F [25°C] and 115°F [46°C]).

2. REFERENCED DOCUMENTS

2.5 LTPP Protocol

Protocol P21 - Recovery of Asphalt from Solution by the Abson Method.

6. APPARATUS

6.3 Delete

6.7.2 Delete

7. PREPARATION OF SAMPLE

7.1 Heat the extracted asphalt cement sample with care to prevent local overheating until it has become fluid. Then with constant stirring, raise the temperature of the asphalt cement sample to not more than 180°F (100°C) above its estimated or expected softening point. Avoid the inclusion of air bubbles. To reach the pouring temperature, do not heat the softened sample more than 30 minutes. Then, pour it into the sample container to a depth, that when cooled to the temperature of test, is at least 10 mm (0.4 in.) greater than the depth to which the needle is expected to penetrate. Pour separate samples for each of the test temperatures (77°F [25°C] and 115°F [46°C]).

8. TEST CONDITIONS

8.1 The conditions of the test (i.e., temperature, load, and time) for this protocol shall consist of (1) 77°F (25°C), 100 g (0.2 lb) and 5 s and (2) 115°F (46°C), 100 g (0.2 lb) and 5 s.

9. PROCEDURE

In accordance with Section 9 of AASHTO T49-87 for two separate specimens from the same asphalt cement sample at 77°F (25°C) and 115°F (46°C) (i.e., one at 77°F [25°C] and one at 115°F [46°C]).

9.4 Calculate the Penetration Index using the following formula:

PI equals the ratio of 20 minus 500 times A over 1 plus 50 times A

where: PI = Penetration Index and

A equals (log of pen at 115 degrees fahrenheit minus the log of pen at 77 degrees fahrenheit) divided by 21.1

Pens in millimeters @ 100 gm., 5 sec.

10. REPORT

Report the following information on Form T22.

10.1 Sample identification shall include: Laboratory Identification Code, Region, State, State Code, SHRP ID, Field Set Number, Sampling Area Number, Layer Number, Location Number and LTPP Sample Number.

10.2 Test Identification shall include: LTPP Test Designation, LTPP Protocol Number, Laboratory Test Number and the Test Date.

10.3 Test Results

10.3.1 Report, to the nearest whole unit, the average of at least three penetrations on the same sample, whose values do not differ by more than the amount shown below for each test temperature:

Penetration Max Difference Between Highest and Lowest PEN
P = 49 2
50 = P = 149 4
150 = P = 249 6
250 = P 8

10.3.2 If the differences are exceeded, repeat the test using a second sample from the same batch of asphalt cement.

10.3.3 If the appropriate tolerance is again exceeded, ignore all results and repeat the test completely.

10.3.4 Penetration index to the nearest decimal place.

10.3.5 Comments shall include LTPP standard comment code(s) as shown in Section 4.3 of this Guide, and any other note as needed.

LTPP LABORATORY MATERIAL HANDLING AND TESTING
LABORATORY MATERIAL TEST DATA
PENETRATION OF EXTRACTED ASPHALT CEMENT AT 77 AND 115°F
TEST DATA SHEET T22

ASPHALT CONCRETE LAYER (ASPHALT CEMENT PROPERTIES)
LTPP TEST DESIGNATION: AE02/LTPP PROTOCOL P22

LABORATORY PERFORMING TEST:______________________________________________________________PRIVATE

LABORATORY IDENTIFICATION CODE: __ __ __ __

REGION _________________ STATE ___________________ STATE CODE __ __

EXPERIMENT NO _____ SHRP ID __ __ __ __

SAMPLED BY: ______________________________________________ FIELD SET NO. __ __

DATE SAMPLED: __ __-__ __-__ __ __ __ SAMPLING AREA NO. SA-____

1. LAYER NUMBER (FROM LAB SHEET L04 AND FORM T01B) __

2. LOCATION NUMBER __ __ __

3. LABORATORY TEST NUMBER __

4. LTPP SAMPLE NUMBER __ __ __ __

5. PENETRATION @ 77°F (millimeters) __ __ __.

6. PENETRATION @ 115°F (millimeters) __ __ __.

7. PENETRATION INDEX __.__

8. COMMENTS

      (a) CODE __ __ __ __ __ __ __ __ __ __ __ __

      (b) NOTE _______________________________________________________

9. TEST DATE __ __-__ __-__ __ __ __

GENERAL REMARKS:___________________________________________________________________________
SUBMITTED BY, DATECHECKED AND APPROVED, DATE
____________________________________________________________
LABORATORY CHIEF
Affiliation______________________
Affiliation______________________

 

<< PreviousContentsNext >>

The Federal Highway Administration (FHWA) is a part of the U.S. Department of Transportation and is headquartered in Washington, D.C., with field offices across the United States. is a major agency of the U.S. Department of Transportation (DOT).
The Federal Highway Administration (FHWA) is a part of the U.S. Department of Transportation and is headquartered in Washington, D.C., with field offices across the United States. is a major agency of the U.S. Department of Transportation (DOT). Provide leadership and technology for the delivery of long life pavements that meet our customers needs and are safe, cost effective, and can be effectively maintained. Federal Highway Administration's (FHWA) R&T Web site portal, which provides access to or information about the Agency’s R&T program, projects, partnerships, publications, and results.
FHWA
United States Department of Transportation - Federal Highway Administration