01020465

Component

https://doi.org/10.3141/1967-04

http://scholar.google.com...cher&publication_year=2006

Low-volume roads in regions susceptible to freezing and thawing periods are often at risk of load-related damage during the spring thaw. Reduced support capacity during this period results from excess melt water that becomes trapped above underlying frozen layers. Many agencies place spring load restrictions (SLRs) during the thaw period to reduce damage to roadways. The period of SLRs set forth by the Minnesota Department of Transportation is effective for all flexible pavements; however, experience suggests that many aggregate-surfaced roads require additional time relative to flexible pavements to recover strength sufficient to carry unrestricted loads. An investigation was performed to improve local agencies’ abilities to evaluate the duration of SLR on aggregate-surfaced roadways. This was accomplished through seasonal measurements of in situ shear strengths, measured with the dynamic cone penetrometer, on various Minnesota county routes. In situ strength tests were conducted on selected county gravel roads over the course of 3 years. Strength levels recorded during the thaw-weakened period were compared with fully recovered periods that typically occur in late spring or summer. Results indicate that aggregate-surfaced roads generally require 1 to 3 additional weeks over that required by flexible pavements to reach recovered bearing capacity.

01037970

English

pp 27-35

2006

Transportation Research Record: Journal of the Transportation Research Board

0309099765

Print

Figures (6) ; References (6)

Bearing capacity; County roads; Flexible pavements; Gravel roads; Load limits; Low volume roads; Seasonally frozen ground; Shear strength; Thaw; Time duration

Design; Highways; Pavements; I22: Design of Pavements, Railways and Guideways; I23: Properties of Road Surfaces

PRP, TRIS, TRB, ATRI

Mar 3 2006 11:11AM

• Asphalt Multi-Integrated Rollers and Steel Drum Compactors: Evaluating Effect of Compaction on Permeability of Asphalt Pavements
• Comparative Design Case Studies of Pavement Performance on Expansive Soils
• Design Model for Roughness and Serviceability of Pavements on Expansive Soils
• Effectiveness of Open-Graded Base Layer on Subgrade Moisture Regime and Overall Pavement Performance
• Estimating Thermal Conductivity of Pavement Granular Materials and Subgrade Soils
• Estimation of Expected Moisture Contents for Pavements by Environmental and Soil Characteristics
• Evaluation of Resilient Modulus Model Parameters for Mechanistic–Empirical Pavement Design
• Field Monitoring of Moisture Variations Under Flexible Pavement
• Hauling with Full Axle Weights and Reduced Tire Pressures on Weight-Restricted Roads in British Columbia
• Implementation of Spring Load Restrictions Using a Deflection-Calibrated Thaw Index
• Investigations of Environmental and Traffic Impacts on "Mechanistic-Empirical Pavement Design Guide" Predictions
• Laboratory Evaluation of Untreated and Treated Pavement Base Materials: Repeated Load Permanent Deformation Test
• Resilient Modulus Estimation System for Fine-Grained Soils
• Safety and Cost-Effectiveness of Approach Guardrail for Bridges on Low-Volume Roads
• Safety Effectiveness of Stop Control at Ultralow-Volume Unpaved Intersections
• Two-Dimensional Moisture Flow–Soil Deformation Model for Application to Pavement Design