Implementation of stress-dependent resilient modulus of asphalt-treated base for flexible pavement design

The U.S. Army Engineer Research and Development Center (ERDC) of the U.S. Army Corps of Engineers has initiated an effort to modernize the Department of Defense (DOD) pavement design and evaluation procedures initially developed in the 1950s. Flexible pavement analyses and evaluations are currently performed based on the elastic layered WESLEA and WESDEF software programs. To modernize the current pavement design and evaluation procedures used by the DOD, an advanced axisymmetric Finite Element Method (FEM) based analysis program, named C-FLEX, was developed and is introduced in this paper. The C-FLEX program is designed to feature accurate material models for all pavement layers with the capability to model the cross-anisotropic and nonlinear elastic properties of unbound base/subbase and subgrade layers, the viscoelastic behavior of the asphalt mixture, as well as mechanical reinforcement using geosynthetics in flexible pavements. The FEM formulation in C-FLEX and the program architecture and implementation details are introduced and discussed in this paper. The different analysis schemes and proper models used to characterize the cross-anisotropy and stress-dependent material nonlinearity are also described in detail. The viscoelastic analysis scheme and the geosynthetic characterization are currently under development and so are not included in this paper. Furthermore, two conventional flexible pavements with different layer properties are analyzed to verify the solutions and reliability of the C-FLEX program. Based on this development effort with ERDC, the C-FLEX program is envisioned to eventually serve as the flexible pavement analysis engine for the DOD’s new mechanistic design and evaluation platform.

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Analysis of CBR design value selection methods on flexible pavement design: Colombia case study

International Journal of Engineering & Technology ◽

10.14419/ijet.v9i2.30628 ◽

2020 ◽

Vol 9 (2) ◽

pp. 509

Author(s):

Otto Mora L. ◽

Michel Murillo A. ◽

Tiana Rosania A. ◽

Abraham Castañeda A. ◽

Rosa Pinto C. ◽

...

Keyword(s):

Comparative Analysis ◽

Resilient Modulus ◽

Flexible Pavement ◽

Pavement Design ◽

Selection Methods ◽

Essential Variable ◽

The Mean ◽

Design Value ◽

Criterion Method

A comparative analysis was carried out to observe the variation of a flexible pavement structural thickness, due to the use of different meth-ods to calculate the CBR design value, as an essential variable to estimate the Subgrade Resilient Modulus (Mr) through an empirical corre-lation. The Asphalt Institute Method and the Mean Criterion Method were applied to calculate de Design CBR value of a homogeneous roadway division from a representative track section located in the Bolivar Department, Colombia. As a result, the Design Percentiles of the CBR design unit were expanded for the Asphalt Institute method, thus, allowing the approach of more reliable and safe designs, considering that this method limits the selection percentiles to three traffic levels.

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Pavement Design Comparative Analysis Using Bina Marga Design Method (Pt T-01-2002-B) And Pavement Design Manual (No.04/Se/Db/2017) (Case Study: Trisakti Port - Liang Anggang)

POROS TEKNIK ◽

10.31961/porosteknik.v9i1.511 ◽

2018 ◽

Vol 9 (1) ◽

pp. 36

Author(s):

Utami Sylvia Lestari ◽

Nurhafni Karina Resentia

Keyword(s):

Resilient Modulus ◽

Design Method ◽

Flexible Pavement ◽

Pavement Design ◽

Traffic Load ◽

Main Variable ◽

Pavement Layers ◽

Bearing Capacity Factor

Traffic load repetition is the main variable in flexible pavement layers design. In addition, a soil bearing capacity factor is also required for determining the thickness of the flexible pavement layer so that the pavement had been designed will be in good perfomance during the that period. The determination of thickness layers using the 2002 method (Pt T-01-2002 B) is based on the traffic load during the design period and subgrade resilient modulus value. Meanwhile the 2017 method (Pavement design manual No. 04/SE/Db/2017), layers thickness was determined based on traffic load and CBR subgrade value. Based on the calculation using both methods, the pavement layers thickness with the pavement design manual 2017 method is more thick than 2002 method. While the ESAL calculation using both methods, the 2002 method value is more larger than the pavement design manual 2017 method.

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