Review of Lightweight Deflectometer for Routine In Situ Assessment of Pavement Material Stiffness
The use of a portable lightweight deflectometer (LWD) for construction quality control or material investigation for earthworks and road construction is increasing around the world. LWD is reviewed as a field evaluation tool, the test variables and data quality are discussed, and the usefulness and limitations for a variety of earthwork and road assessment scenarios are described. A state-of-the-art reference document is provided for LWD users, consultants, material specifiers, contractors, and clients. Data from road foundations (subgrades, granular capping, and subbase) and fully constructed in-service (thinly surfaced) roads were reviewed to demonstrate the flexibility of the LWD and to show that its determination of stiffness modulus may differ from that of the conventional falling weight deflectometer to a varying extent. A series of laboratory investigations was undertaken to demonstrate the sensitivity to uniformity of plate–surface contact and the limitations in the interpretation of peak displacement from the device. A good understanding of the device workings and careful specification of the test variables are required both to analyze the data correctly and to permit comparison between data sets. It is concluded that the device is a useful and versatile field quality control and pavement investigation tool if an understanding of the device issues is considered by data users.
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- Summary URL:
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Availability:
- Find a library where document is available. Order URL: http://www.trb.org/Main/Public/Blurbs/159491.aspx
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Authors:
- Fleming, Paul Richard
- Frost, Matthew William
- Lambert, John Peter
- Publication Date: 2007
Language
- English
Media Info
- Media Type: Print
- Features: Figures; Photos; References; Tables;
- Pagination: pp 80-87
- Monograph Title: Soil Mechanics 2007
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Serial:
- Transportation Research Record: Journal of the Transportation Research Board
- Issue Number: 2004
- Publisher: Transportation Research Board
- ISSN: 0361-1981
Subject/Index Terms
- TRT Terms: Deflectometers; Earthwork; Field tests; Foundation soils; Laboratory tests; Quality control; Road construction; Stiffness; Subbase (Pavements); Subgrade (Pavements)
- Uncontrolled Terms: Granular subbases; Lightweight deflectometers
- Subject Areas: Construction; Geotechnology; Highways; I51: Earthworks and Soil Drainage;
Filing Info
- Accession Number: 01046318
- Record Type: Publication
- ISBN: 9780309104302
- Files: TRIS, TRB, ATRI
- Created Date: Apr 24 2007 7:19AM