Details:

Alternative Title:
Project title: Using imaging analysis technology to improve the laboratory and field compaction of HMA
Creators:
Masad, Eyad ; Kassem, Emad ; Chowdhury, Arif
Masad, Eyad ; Kassem, Emad ; Chowdhury, Arif Less -
Corporate Creators:
Texas Transportation Institute
Corporate Contributors:
Texas. Dept. of Transportation. Research and Technology Implementation Office
Subject/TRT Terms:
[+]
Aggregates Aggregates (Building Materials) Asphalt Concrete Asphalt Concrete--Evaluation Pavements Pavements--Performance--Texas
Publication/ Report Number:
FHWA/TX-09/0-5261-1
Resource Type:
Tech Report
Geographical Coverage:
Texas
Edition:
Technical report; Sept. 2005-May 2008.
Corporate Publisher:
Texas Transportation Institute
Abstract:
Field compaction of asphalt mixtures is an important process that influences performance of asphalt

pavements. This study evaluates the relationship between different field compaction patterns and the

uniformity of air void distribution in asphalt pavements. A number of projects with different hot mix asphalt

(HMA) types were compacted, and cores were taken at different locations from these projects. The X-ray

Computed Tomography (X-ray CT) system was used to capture the air void distributions in these cores. The

analysis results have revealed that the uniformity of air void distribution is highly related to the compaction

pattern and the sequence of using different compaction equipment. More importantly, the efficiency of

compaction (reducing air voids) at a point was found to be a function of the location of this point with

respect to the roller compactor width.

The results in this paper have supported the development of the “Compaction Index (CI),” which

quantifies the degree of field compaction. The CI is a function of the number of passes at a point and the

position of the point with respect to the compaction roller width. This index was found to correlate

reasonably well with percent air voids in the pavement. The CI calculated from field compaction had a good

relationship with the slope of the compaction curve obtained from the Superpave gyratory compactor. This

relationship offers the opportunity to predict field compactability based on laboratory measurements. The

compaction of longitudinal joints was investigated, and recommendations were put forward to improve joint

compaction. The air void distributions in gyratory specimens were related to the mixture mechanical

properties measured using the Overlay and Hamburg tests.


Format:
PDF
Funding:
0-5261
Collection(s):
US Transportation Collection
Main Document Checksum:
[+]
urn:sha256:944416098bf9910031d77bfdbc532154fed636a474508d9b73fea9b19d8dd9a7
Download URL:
https://rosap.ntl.bts.gov/view/dot/16838/dot_16838_DS1.pdf
File Type:

Supporting Files

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