Research Activities: 2012

Reliability-based Optimization Design of Geosynthetic Reinforced Road Embankment

Status Complete                 View Final Report: PDF
Sequential Number R353
Identification Number 00042706
Matching Research Agency

Missouri University of Science and Technology

Principal Investigator

Ronaldo Luna
Missouri University of Science and Technology
1401 N. Pine Street
Rolla, MO 65409
(573) 341-4484

Student Involvement

One graduate student

Project Objective To develop reliability-based algorithms with the fundamental mathematics
and statistics that account for the spatial soil property variability. This will optimize the design of roadway embankments including geosynthetic inclusions in the embankment fill.
Project Abstract Road embankment is normally a large structure, the construction of which
requires for large amounts of soil normally of good quality. In order to limit costs, the utilization of geosynthetic in road embankment allows for construction of steep slopes up to 80 - 85 degrees, which can save vast amounts of fill soil and land take compared to a traditional unreinforced one.
It then requires for a stability analysis regarding the geosynthetic reinforced slope, which is highly depending on the selection and properties of geosynthetic including the tensile strength, transfer efficiency, length and number of geosynthetic layers placed in embankment, etc. To
minimize costs, the optimization design is necessary to select an optimal combination of those design parameters. In this study, the reliability-based optimization (RBO) will be implemented on the basis of reliability-based probabilistic slope stability analysis considering the variability of soil properties. RBO intends to minimize the cost involved in geosynthetic reinforced road embankment design while satisfying all technical requirements. The limit equilibrium method will be embedded to compute the factor of safety (FS), meanwhile, the MPP-based first-order
reliability method (FORM) will be performed to determine the probability of failure (pf). The cost is assumed as a function of design parameters: the number of geosynthetic layers, embedded length, and the tensile strength of geosynthetic. Coupling with the reliability assessment and some other technical constraints, the combination of design parameters can be  optimized for a minimum cost.

Relationship to other Research/Projects

This project is a seed type project to other applications in civil infrastructure, such as dams, levees, and roadways embankment. The introduction of spatial statistics in the 2D design of the critical cross-section of a reinforced earth structure is new and a true contribution to the state of the art in geotechnical engineering. Many other national and international researchers are trying similar approaches.


Transportation-Related Keywords

Embankments, slopes, reinforced, reliability-based

Technology Transfer Activities

Delivery of presentations in technical conferences, which involve manufactures, engineers and researchers. Such as, ASCE GeoInstitute and
Transportation Research Board.


Project Deliverables

The mathematical constructs, algorithm and code will be available in
both written report format and syntax and, as necessary. Matlab *.m scripts will also be available.

Anticipated Benefits

This tool will allow DOTs to design using a reliability-based procedure
that allows the variability of soil properties and geosynthetic inclusions for reinforcement. The deliverables in the next section will be available to the DOT and related investigators.


Project Start Date: 05/15/2013
Project End Date: