Estimate of Resilient Modulus of Graded Aggregate Base in Flexible Pavement

2014 ◽  
Author(s):  
Sung-Hee Kim ◽  
Jidong Yang ◽  
Samuel Beadles
Keyword(s):  
Resilient Modulus ◽  
Flexible Pavement ◽  
Aggregate Base

Use of Shredded Rubber in Unbound Granular Flexible Pavement Layers

1996 ◽  
Vol 1547 (1) ◽  
pp. 96-106 ◽  
Author(s):  
Richard H. Speir ◽  
Matthew W. Witczak
Keyword(s):  
Resilient Modulus ◽  
Constitutive Models ◽  
Friction Angle ◽  
Flexible Pavement ◽  
Partial Replacement ◽  
Universal Model ◽  
Rubber Blends ◽  
State Highway ◽  
Base Course ◽  
Aggregate Base

The major objective of the research was to conduct a study into the feasibility of using shredded rubber as a partial replacement for aggregate within conventional base and subbase materials in a flexible pavement system. A graded aggregate base and sand subbase meeting specifications for the Maryland State Highway Administration were used. The rubber used in the study consisted of a shredded product with 60 to 70 percent retained on a 9.5-mm (⅜-in.) sieve. This size was selected because of the relatively inexpensive cost to produce it and because of its adaptability to an aggregate blend. Modified and standard Proctor, California bearing ratio (CBR), and resilient modulus tests were conducted on the base/subbase-rubber blends with up to 15 percent rubber content by weight. The aggregate base blend resulted in significant decreases in both CBR and nonlinear resilient modulus at 15 percent rubber. These significant reductions led the authors to conclude that the use of shredded rubber in a dense-graded aggregate base course is not feasible. In contrast, the sand-subbase blends resulted in insignificant changes to the CBR, friction angle, permeability, and resilient modulus at higher rubber percentages. It was concluded that the sand-rubber sub-base exhibits little change compared with the virgin sand-subbase material. As a result the use of shredded rubber may be a technically feasible alternative in the construction process. Finally, two constitutive models were used in the resilient modulus analysis: the conventional K1, K2 model and a universal model incorporating an octahedral stress term (k1, k2, k3 model). Direct comparisons revealed greatly improved predictability and accuracy with the universal model for assessing the nonlinear behaviors of both aggregate types evaluated.

Variation of Resilient Modulus of Aggregate Base and Its Influence on Pavement Performance

1998 ◽  
Vol 26 (4) ◽  
pp. 329 ◽  
Author(s):  
DR Petersen ◽  
RE Link ◽  
P Tian ◽  
MM Zaman ◽  
JG Laguros
Keyword(s):  
Resilient Modulus ◽  
Pavement Performance ◽  
Aggregate Base

Assessment of Falling Weight Deflectometer Data for Stabilized Flexible Pavements

2000 ◽  
Vol 1709 (1) ◽  
pp. 19-25 ◽  
Author(s):  
Alexander K. Appea ◽  
Imad L. Al-Qadi
Keyword(s):  
Resilient Modulus ◽  
Ground Truth ◽  
Monitoring And Evaluation ◽  
Structural Condition ◽  
Base Layer ◽  
Falling Weight Deflectometer ◽  
Structural Capacity ◽  
Pavement Monitoring ◽  
Aggregate Base ◽  
Falling Weight

Backcalculation of pavement moduli through the utilization of the falling weight deflectometer (FWD) is used for pavement monitoring and evaluation. The performance and structural condition of nine flexible pavement test sections built in Bedford County, Virginia, have been monitored over the past 5 years using FWD. The nine sections include three groups with aggregate base layer thicknesses of 100, 150, and 200 mm, respectively. Sections 1, 4, and 7 are control, whereas Sections 2, 5, 8 and 3, 6, 9 are stabilized with geotextiles and geogrids, respectively. The FWD testing used five double-load drops ranging from 26.5 to 58.9 kN. The deflection basins obtained from the testing have been analyzed using the ELMOD backcalculation program to find the pavement structural capacity and to detect changes in the aggregate resilient modulus. The analysis shows a reduction in the backcalculated resilient modulus of the 100-mmthick base layer. The reduction was 33 percent over 5 years for the nonstabilized section compared with the geosynthetically stabilized section. The reduction in base layer resilient modulus may have resulted from subgrade fine migration into this layer as confirmed by excavation. The study confirms the effectiveness of using woven geotextile as a separator in a pavement system built over weak subgrade. This supports the continuous rutting measurements and ground truth excavation conducted in late 1997.

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

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.  

scholarly journals 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 ◽  
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.

Sign in / Sign up

Export Citation Format

Share Document