Mechanistic-empirical overlay design method for reflective cracking

Reflective cracking of flexible pavements phase i and ii. Citeseerx document details isaac councill, lee giles, pradeep teregowda. Mechanisticempirical overlay design method for reflective cracking article pdf available in road materials and pavement design 18091 january. In view of the the imperfection of design method of asphalt overlay on old cement under heavyload traffic, and with the background of a successful practice of repaving improvement project in xia jiayingfen yang expressway, this article analyzes the mechanical response of the old cement concrete road slab and the overlay, takes the influence of the void under slab on the life. Reflective cracking, pcc pavements, hma overlay, finite element analysis, viscoelastic constitutive model.

Currently, reflection cracking is not considered in most existing asphalt overlay thickness design programs, including the mechanisticempirical pavement design guide developed under the nchrp project 7a. The design system developed incorporates models for both rutting and reflection cracking of the proposed overlay. A new and innovative mechanistically based pavement overlay design method is described that considers the most predominant type of overlay distress observed in the field. Mechanistic empirical pavement design guide mepdg april 15, 20 aci convention. As compared to the sb mix, the use of pm asphalt mixture in the leveling course reduced the level of longitudinal tensile stress at the bottom of the hma overlay above the pcc joint by approximately 30%. The temperature effect on the reflective cracking of. Development and performance of interlayer stressabsorbing composite in asphalt concrete overlays b. Project 190600 from the ltpp program sps6 database served as the basis for the composite pavement case study. Using falling weight deflectometer data with mechanistic. Mechanisticempirical overlay design method for reflective cracking download. Reflective cracking above old cracks in the underlying pavement surface. Final report, part 3 design analysis, ch 6, national cooperative.

Calibration of pavement response models for the mechanisticempirical pavement design method. Pavement performance pavement preservation pavement rehabilitation pavements performance permanent deformation phase angle reflective cracking rheology rubber rubberized asphalt rubberized asphalt concrete. It is found that the three different mathematical models provide lower and upper limits for roughness, rutting, and reflective cracking. Reflection cracking, however, has been a serious concern associated with asphalt overlays for a long time. The existing pavement may be either hma or portland cement concrete pcc. Mechanisticempirical design proceduresbased on mathematically calculated.

This study investigates the dependence of overlay field cracking performance on overlay thickness and fracture energy of asphalt mixture. Concrete overlay type design methods unbonded on asphalt, composite, or concrete aashto me, acpa streetpave 12. A rehabilitation method that has recently gained popularity to extend the life of deteriorated. Pdf a mechanisticempirical based overlay design method. Samir has been given a reflective cracking equivalent thickness of 15 mm of asphalt rubber hot mix overlays or 30 mm of dense graded hot mix overlays. Guide for mechanisticempirical design of new and rehabilitated pavement structures 2004.

Reflective cracking can be defined as cracks in the ac overlay that are directly above joints or above existing cracks in the underlying pcc pavement structure. A total of 15 pavement sections in minnesota for which diskshape compact tension dct testing was performed on field cores from overlays were used for the study. Reflection crackingbased asphalt overlay thickness design. The two types of overlay materials studied were densegraded hot mix asphalt and gapgraded asphalt rubber. Mechanisticempirical overlay design method for reflective cracking. International journal of road materials and pavement design. Structural models predict responses of pavement stresses, strains, deflections to loads and. However, the performance of these hma overlaid pavements is hindered due to the occurrence of reflective.

Rehabilitation of concrete pavements utilizing rubblization. A mechanisticempirical based overlay design method for reflective cracking article pdf available in road materials and pavement design 63. The finite element analysis confirms the quantified reflective cracking benefits of samir and provides optimum design alternatives to conventional dense grades asphalt concrete overlays. Asphalt mix fracture energy based reflective cracking. Introduction the rubber pavements association rpa contracted with consulpav in 1999 to develop a mechanistic overlay design method for reflective cracking. These methods come from highway engineering, a field of study in which asphalt rubber mixes have often been applied with the goal of controlling reflective cracking. The first method, the 1993 aashto guide, is the procedure most commonly used today for concrete overlay thickness design. Reflective cracking above old cracks in the underlying pavement.

Concrete pavement rehabilitation procedure using resonant. Mechanisticempirical design guidea manual of practice aashto 2008 5. Then, the mechanisticempirical pavement design guide mepdg was used for predicting the progression of the pavement distress and to estimate the effect of the three different models on such phenomena. A mechanisticempirical model for topdown cracking of asphalt pavements layers develops a calibrated mechanisticempirical me model for predicting the loadrelated topdown cracking in the asphalt layer of flexible pavements. Investigation on pavement me design reflective cracking, faulting, iri prediction models, concrete overlays design tool, and performance threshold levels for iowa.

Hot mix asphalt hma overlay is the most commonly used rehabilitation technique for such deteriorated pcc pavements. This article will consider the mechanisticempirical overlay design method for reflective cracking. Effect of laboratory compaction method on permanent deformation characteristics of asphaltaggregate mixtures. This paper describes a new pavement overlay design method that takes into account the reflective cracking as the most predominant type of overlay distress.

Mechanical stabilization of intermediate granular layers. Reflective cracking is cracking that occurs in a hot. Montana slim a prairie legend 19441952 1959 bear family 4cd. Mechanistic overlay design method based on reflective cracking concepts, final report for rubber pavements association, consulpav international. Deterioration in portland cement concrete pcc pavements can occur due to distresses caused by a combination of traffic loads and weather conditions. Use of mechanisticempirical performance simulations to. Use of mechanisticempirical performance simulations to adjust. Reflective cracking is formed when the reflection of an existing crack or joint propagates upward to the new pavement surface. Cores and beams were sawed from the rolling wheel compacted slabs.

Design of concrete overlays using existing methodologies. Implementation of the aashto mechanisticempirical pavement design guide and software documents the experience of transportation agencies in the implementation of the 2008 american association of state highway and transportation officials aashto mechanisticempirical pavement design. Mechanisticempirical asphalt overlay thickness design and. Journal of the transportation research board, 1809 2002, 209217. A new and innovative mechanistically based pavement overlay design method is described tha that considers the most predominant type of overlay distress observed in the field. The mepdg is currently being implemented and evaluated by numerous. Study on design method for asphalt overlay on old cement. A mechanisticempirical based overlay design method for. This paper presents a design method for pavement overlay that is mechanistically and empirically based and considered with reflective overlay cracking in mind specifically. Asphalt rubber papers store asphalt rubber papers store. Although hma overlay was commonly used as one of the rehabilitation strategies for the existing pcc pavements in china, this repair method has proven less than satisfactory owing to reflective cracking. Trbs national cooperative highway research program nchrp synthesis 457. Mechanisticempirical overlay design method for reflective.

Using falling weight deflectometer data with mechanisticempirical design and analysis, volume ii. A mechanisticbased overlay design method was used to predict the reflective cracking overlay life. Development of a mechanisticempirical based overlay. Each sixinch 150mm diameter by twoinch 50mm thick core was tested with a reflective crack testing device rcd specifically designed and built for use in this research project. Chapter two mechanisticempirical pavement design guide. Trbs national cooperative highway research program nchrp webonly document 257. Very little reflective cracking has been observed in unbonded overlays. Development of a mechanisticempirical based overlay design method for reflective cracking. Reflective cracking is cracking that occurs in a hot mix asphalt hma overlay after it has been applied to an existing cracked paved surface. Concrete pavement overlay design jeffery roesler, ph. This chapter discusses the development of an overlay design procedure that will.

This paper describes a new and innovative mechanistically based pavement overlay design method that considers the most predominant type of overlay distress observed in the field. A mechanistic based approach to hma overlay thickness design. A mechanisticempirical based overlay design method for reflective cracking. Also, there appeared to be a need to develop a mechanistic reflective cracking model and overlay design method to compliment the new 2002 pavement design guide, which will focus on mechanistic methods of pavement design. The program provides an estimate of the lime and number of traffic load to failure by reflective cracking.