Home  /   AASHTO T321 PDF

AASHTO T Standard Method of Test for Determining the Fatigue Life of Compacted Asphalt Mixtures Subjected to Repeated Flexural Bending. standard . AASHTO T/TP8 is a Test Standard for Determining the Fatigue Life of Compacted Hot-Mix Asphalt (HMA) Subjected to Repeated Flexural Bending. AASHTO T (AASHTO, ) and the European Standard (EN , ). When evaluating fatigue resistance through four point bending beam.

Author: Zologami Arashilabar
Country: Guyana
Language: English (Spanish)
Genre: Music
Published (Last): 16 December 2016
Pages: 54
PDF File Size: 15.50 Mb
ePub File Size: 14.46 Mb
ISBN: 491-6-94464-143-5
Downloads: 44328
Price: Free* [*Free Regsitration Required]
Uploader: Kedal

Thank you for interesting in our services.

We need your help to maintenance this website. Prepare a plot of stiffness versus load cycles as shown in Figure 7. Report the xashto test temperature to the nearest 0.

It is t3321 to cut beams from a large slab compacted by a vibratory roller. Size px x x x x Apply 50 load cycles at a constant strain of to microstrain. Precision—The research required to develop precision values has not been conducted.

The loading device shall be capable of 1 providing repeated sinusoidal loading at a frequency range of 5 to 10 Hz; 2 subjecting specimens to four-point bending with free rotation and horizontal translation at all load and reaction points; and 3 forcing the specimen back to its original position i.

Please copy and paste this embed script to where you want to embed Embed Script.

Reliable results depend on many factors following the suggestions of Specification D or some similar acceptable guideline that provides a means of aashtoo and controlling some of those factors. Initial Stiffness Pa —The initial stiffness is determined by plotting stiffness S against load cycles n and best-fitting the data to an exponential function of the form shown in Equation 7.


Test System—The test system shall consist of a loading device, an environmental chamber optionaland a control and data acquisition system. Please aasht us to share our service with your friends.


Specimen Measurement—Measure the height and width of the specimen axshto the nearest 0. No other units of measurement are included in this standard. An environmental chamber is not required if the temperature of the surrounding environment can be maintained within the specified limits. Fatigue life; flexural bending; hot mix asphalt fatigue; hot mix asphalt flexural testing; hot mix asphalt tensile testing; hot mix asphalt stiffness; hot mix asphalt energy aashyo. Report the test results listed in Table aashtl for each load cycle interval selected by the operator to three significant figures.

Figure 7 presents a typical plot of stiffness versus load cycles. Place the specimen in an environment that is at Specimen Dimensions—Report the specimen length, average specimen height, and average specimen width in meters to four significant figures.

AASHTO T, Test equipment Controls

Use the awshto to ensure proper horizontal spacing of the clamps, mm center-to-center. Attach the LVDT block to the r321 by screwing the screw into the nut epoxied on the specimen. Determine the specimen stiffness at the 50th load cycle. Observe standard laboratory safety precautions when preparing and testing HMA specimens. See Figure 6 for a typical dissipated energy versus load cycle plot.

We need your help! Referenced Documents purchase separately The documents listed below are referenced within the subject standard but are not provided as part of the standard.

For loading devices that require gluing a nut for deformation measurement, these cut surfaces provide smooth surfaces for mounting the measurement gauges. The fatigue life tt321 failure energy determined by this standard can be used to estimate the fatigue life of HMA pavement layers under repeated traffic loading.


These notes and footnotes excluding those in tables and figures shall not be considered as requirements of the standard. The performance aqshto HMA can be more accurately predicted when these properties are known.

Activate the recording and control components so that the test results at the selected load cycle intervals are monitored and recorded, ensuring that the test system is operating properly. When the specimen has experienced greater aashot 50 percent reduction in stiffness, terminate the test.

The area under the curve represents the cumulative dissipated energy. The load cycle at which failure occurs is computed by solving for n from Equation 7, or simply: The total dissipated energy to failure is summarized as part of the output. Next, close the inside clamps by applying sufficient pressure to hold the specimen in place. This stiffness is an estimate of the initial stiffness, which is used as a reference for determining specimen failure.

This standard may involve hazardous materials, operations, and equipment. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.