01620234

Component

https://doi.org/10.3141/2655-02

Unbound aggregate base and subbase courses consist of coarse-grained materials with limited percentages of fines (i.e., passing the No. 200 sieve) allowed. The fines are mineral fillers that occupy the void spaces between the sand and gravel-sized particles. An excessive quantity of fines can negatively affect the strength characteristics of unbound aggregate layers, and this effect can easily be aggravated when the matrix is saturated. A set of unsoaked and soaked California bearing ratio (CBR) tests were performed on engineered gradations of unbound aggregate samples so that the effect of soaking on CBR test results could be studied. A detailed comparison between soaked and unsoaked CBR results was carried out by considering various index properties, such as the fines content, plasticity index, and dust ratio (percentage passing the No. 200 sieve divided by the percentage passing the No. 40 sieve). It was found that higher plasticity indexes, such as 9% and 13%, have a negative effect on both soaked and unsoaked CBR values for samples with a dust ratio of 1.0. Samples with a dust ratio of 0.4 were, in general, not influenced by soaking in terms of the CBR index. Moreover, the effect of soaking on strength reduction was noticeable when the fines content was as high as 12% and the dust ratio was greater than 0.6. Furthermore, a correlation between soaked and unsoaked CBR is also proposed on the basis of experimental results obtained from this study.

01629558

17-04666

English

pp 13–19

2017

Transportation Research Record: Journal of the Transportation Research Board

9780309441568

Digital/other

Figures (6) ; References (20) ; Tables (2)

Aggregates; Base course (Pavements); California bearing ratio; Dust; Fines (Materials); Subbase (Pavements)

Geotechnology; Highways; Materials; Pavements

TRIS, TRB, ATRI

Dec 19 2016 1:11PM

• Case Study on the Use of Mobile Lidar to Produce a Preliminary Drainage Design
• Ethylene Glycol Accelerated Weathering Test: An Improved, Objective Aggregate Durability Test Method
• Evaluating Constructed Aggregate Layers of Working Platforms and Flexible Pavements: Adequacy of In-Place Quality Control and Quality Assurance Techniques
• Influence of Maximum Particle Size, Fines Content, and Dust Ratio on the Behavior of Base and Subbase Coarse Aggregates
• Permanent Strain Behavior of Marginal Granular Material
• Shear Wave Velocity Profiles of Roadway Substructures from Multichannel Analysis of Surface Waves and Waveform Tomography
• Strain Rate Effect on Shear Behavior of Open-Graded Aggregates
• Use of Time Domain Reflectometry to Estimate Moisture and Density of Unbound Road Materials: Laboratory Calibration and Field Investigation
• Vibratory Compaction of Base Course Aggregates