Development of design guidelines for proper selection of graded aggregate base in Maryland state highways.

Details

• Creators:
  Aydilek, Ahmet H. ; Haider, Intikhab ; Cetin, Altan ; Kaya, Zulkuf ; Hatipoglu, Mustafa
• Corporate Creators:
  University of Maryland (College Park, Md.)
• Subject/TRT Terms:
  • Base course (Pavements)
  • Aggregate gradation
  • Stiffness
  • Drainage
  • Mechanistic-empirical pavement design
  • Modulus of resilience
  • Moisture content
  • Deformation
  • Field tests
  • Laboratory tests
• Publication/ Report Number:
  MD-15-SP109B4G-1
• Resource Type:
  Tech Report
• Geographical Coverage:
  Maryland
• Corporate Publisher:
  Maryland. State Highway Administration. Office of Policy & Research
• Abstract:
  The mechanical and drainage properties of graded aggregate base material are the level one input in mechanistic ; pavement design. Maryland State Highway Administration (SHA) is in need of guidelines for evaluation of stiffness ; and drainage characteristics of graded aggregate base (GAB) stone delivered at highly variable gradations to the ; construction sites. To fulfill the current need, the mechanical and drainage properties of several Maryland GAB ; materials were evaluated in the laboratory and field. The resilient modulus and hydraulic conductivity test results ; obtained in the laboratory were compared to the field moduli and hydraulic conductivity. The effect of moisture ; content on resilient modulus was also evaluated. Summary resilient modulus, SMR values at Optimum Moisture ; Content (OMC) minus 2% were higher than those at OMC, with few exceptions; however, the permanent ; deformations increased with moisture beyond OMC. The control of moisture content within 2% of OMC would not ; significantly affect the resilient modulus and permanent deformation in construction. It was also concluded that an ; addition of 4-6% fines over the SHA specification limit of 8% resulted in 2-5 times decrease in the laboratory-based ; GAB hydraulic conductivities and an increase in time for 50% completion of the drainage from the highway base. ; The required base thickness increased 2.6 to 7 times as a result of fines increased from 2 to 14% for selected GAB ; materials evaluated. It is recommended that resilient modulus, permanent deformation, as well as hydraulic ; conductivity of GAB materials, are evaluated for designing a highway base with adequate stiffness and drainage ; performance
  More +
• Format:
  PDF
• Funding:
  SP109B4G
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/28445/dot_28445_DS1.pdf
• File Type:
  [PDF - 1.28 MB]
• Collection(s):
  US Transportation Collection
• Main Document Checksum:
  urn:sha256:c10625a805d950f4617f9f2dd6f967fbbc493082f8fdb590f769b5987ab73eaf