Effect of Aggregate Degradation on Volumetric Properties of Georgia's Hot-Mix Asphalt

2007 ◽  
Vol 1998 (1) ◽  
pp. 123-131 ◽  
Author(s):  
Todd Lynn ◽  
Robert S. James ◽  
Peter Y. Wu ◽  
David M. Jared
Keyword(s):  
Hot Mix Asphalt ◽  
Volumetric Properties

Control of Volumetric Properties of Hot-Mix Asphalt by Field Management

1996 ◽  
Vol 1543 (1) ◽  
pp. 125-131
Author(s):  
Prithvi S. Kandhal ◽  
Kee Y. Foo ◽  
John A. D'Angelo
Keyword(s):  
Hot Mix Asphalt ◽  
Linear Regression Analysis ◽  
Volumetric Properties ◽  
Production Test ◽  
Independent Variables ◽  
Dependent Variables ◽  
Preceding Work ◽  
Multiple Variable ◽  
Asphalt Content ◽  
Variable Analysis

Significant differences in the volumetric properties of laboratory-designed and plant-produced hot-mix asphalt (HMA) generally exist as demonstrated by FHWA Demonstration Project No. 74. The volumetric properties include voids in the mineral aggregate (VMA) and voids in the total mix (VTM). Guidelines for HMA contractors are needed to reconcile these differences and maintain control of volumetric properties during HMA production. The HMA mix design and field production test data (such as asphalt content, gradation, and volumetric properties) from 24 FHWA demonstration projects were entered into a data base and statistically analyzed. The objective was to identify and, if possible, quantify the independent variables (such as asphalt content and the percentages of material passing the No. 200 and other sieves) that significantly affect dependent variables VMA and VTM. The statistical analysis methods consisted of correlation analysis, stepwise multiple-variable analysis, and linear-regression analysis. On the basis of preceding work, guidelines have been developed for HMA contractors to reconcile the differences between the volumetric properties of the job mix formula and the produced HMA mix.

scholarly journals SIFAT VOLUMETRIK CAMPURAN LASTON MENGGUNAKAN ASPAL MODIFIKASI GETAH PINUS DAN LIMBAH STYROFOAM

2021 ◽  
Vol 7 (1) ◽  
pp. 66-77
Author(s):  
Ratna Yuniarti ◽  
Hasyim Hasyim ◽  
Rohani Rohani ◽  
Desi Widianty
Keyword(s):  
Specific Gravity ◽  
Asphalt Concrete ◽  
Hot Mix Asphalt ◽  
Negative Impact ◽  
Volumetric Properties ◽  
Mineral Aggregate ◽  
Modified Asphalt ◽  
Pine Resin ◽  
Road Pavement

Sifat volumetrik campuran pada laston merupakan salah satu faktor yang menentukan durabilitas (keawetan) lapis perkerasan jalan. Untuk meningkatkan keawetan lapis perkerasan jalan dan mengurangi dampak negatif terhadap lingkungan dapat dilakukan antara lain melalui modifikasi aspal dengan getah pinus dan limbah styrofoam. Tulisan ini bertujuan untuk mengkaji sifat volumetrik campuran laston menggunakan aspal modifikasi getah pinus dan limbah styrofoam tersebut. Sifat volumetrik campuran laston yang dikaji adalah rongga dalam campuran, rongga di antara mineral agregat, rongga terselimuti aspal, density dan bulk specific gravity. Pada penelitian ini digunakan agregat bergradasi rapat yang dicampur dengan aspal modifikasi pada suhu 155 oC dan dipadatkan 75 kali pada kedua sisinya. Pada seluruh benda uji, prosentase limbah styrofoam yang digunakan adalah 6% sedangkan getah pinus sebesar 0%, 1%, 2% dan 3% terhadap berat aspal modifikasi.  Hasil penelitian menunjukkan bahwa campuran laston yang menggunakan aspal modifikasi getah pinus menghasilkan nilai VFB, density dan bulk specific gravity lebih besar serta nilai VIM dan VMA lebih kecil dibandingkan dengan campuran yang menggunakan aspal modifikasi limbah styrofoam. Dengan nilai VIM dan VMA lebih kecil, campuran yang menggunakan aspal modifikasi getah pinus menghasilkan daya ikat lebih kuat sehingga memiliki durabilitas lebih tinggi. Ditinjau dari persyaratan laston sebagai lapis aus pada perkerasan jalan, penggunaan getah pinus dan limbah styrofoam sebagai modifier aspal memenuhi persyaratan volumetrik campuran. Volumetric properties of asphalt concrete is important factor to determine the durability of road pavement. Improvement the durability of road pavement and reducing negative impact of the environment can be done by using modified asphalt. This article aims to know the volumetric properties of  hot mix asphalt using pine resin and waste styrofoam as asphalt modifier. The volumetric properties include voids in mix, voids in the mineral aggregate, voids filled with bitumen, density and bulk specific gravity.  In this study, a continuously graded aggregate was used and mixed with modified asphalt at 155 oC and compacted with 75 blows on both sides. The percentage of waste styrofoam was 6% whereas the percentages of pine resin where  0%, 1%, 2% and 3% by weight of modified asphalt. From the analysis, it can be concluded that asphalt concrete containing pine resin as  modifier strengthen the binding between asphalt and agregate, due to increasing value of voids filled with bitumen (VFB), density and bulk specific gravity. Durability of asphalt concrete using pine resin as modifier was higher than that of asphalt concrete using waste styrofoam because of decreasing value of voids in mix (VIM) and voids in the mineral aggregate (VMA). Based on the specification of  asphalt concrete wearing course, the use of pine resin and waste styrofoam as asphalt modifier has fulfilled volumetric properties requirements.

Minimum Voids in Mineral Aggregate in Hot-Mix Asphalt Based on Gradation and Volumetric Properties

1996 ◽  
Vol 1545 (1) ◽  
pp. 75-79 ◽  
Author(s):  
John A. Hinrichsen ◽  
John Heggen
Keyword(s):  
Hot Mix Asphalt ◽  
Heavy Traffic ◽  
Field Application ◽  
Mix Design ◽  
Volumetric Properties ◽  
Aggregate Gradation ◽  
Mineral Aggregate ◽  
Traffic Loads ◽  
Recent Developments ◽  
Asphalt Mix

The use of voids in mineral aggregate (VMA) criteria for proper mix design of hot-mix asphalt is a time-honored and fairly successful tool. Recent developments in the field of asphalt mix design have encouraged the use of mixtures with a coarse aggregate structure to resist the effect of heavy traffic loads. By using the equations presented, which account for both aggregate gradation and the volumetric properties of the materials, the mix designer is able to judge the proper VMA requirement for each unique blend of materials. By applying the new equations, the most economical mix may be selected without great risk of reduced durability. Supporting data from field application are presented to illustrate the use of the equations.

scholarly journals Flexible Pavement Performance in relation to In Situ Mechanistic and Volumetric Properties Using LTPP Data

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Mohammad Jamal Khattak ◽  
Nagaraju Peddapati
Keyword(s):  
Hot Mix Asphalt ◽  
Compressive Strain ◽  
Strong Relationship ◽  
Ambient Air ◽  
Flexible Pavement ◽  
Pavement Performance ◽  
Volumetric Properties ◽  
Actual Performance ◽  
Air Voids

This research study focuses on the actual performance of the flexible pavements and its relationship with the in-situ mechanistic and volumetric properties. The data required for the study were obtained using the Long Term Pavement Performance database. Approximately, 116 flexible pavement sections throughout United States were analyzed and discussed. The results indicated that the temperature has a significant affect on the backcalculated modulus of the hot mix asphalt layer. However, no strong relationship was observed between the hot mix asphalt backcalculated modulus and in situ air voids. It was found that fatigue life was a function of tensile strain at the bottom of hot mix asphalt layer, peak surface deflection, hot mix asphalt air voids and maximum specific gravity, and ambient air temperature. Similar relationships between the rut life, mechanistic and volumetric properties were established for wet-freeze and wet-no-freeze climatic zones. The sensitivity analysis revealed that the rut performance in wet-no-freeze sections is mainly affected by higher base and roadbed compressive stresses and strains. On the other hand, the performances in wet-freeze sections are highly depended on roadbed compressive strain and modulus ratio of subbase to roadbed.

Effect of Specimen Size on Compaction and Volumetric Properties in Gyratory Compacted Hot-Mix Asphalt Concrete Specimens

1996 ◽  
Vol 1545 (1) ◽  
pp. 126-132 ◽  
Author(s):  
Kevin D. Hall ◽  
Satish K. Dandu ◽  
Gary V. Gowda
Keyword(s):  
Asphalt Concrete ◽  
Hot Mix Asphalt ◽  
Asphalt Mixture ◽  
Design Procedure ◽  
Specimen Size ◽  
Binder Content ◽  
Volumetric Properties ◽  
Strong Trend ◽  
Number Of Factors ◽  
Gyratory Compaction

Gyratory compaction is the centerpiece of the Strategic Highway Research Program asphalt mixture design procedure Superpave. A number of factors could potentially affect the behavior of asphalt mixes in the gyratory compactor. One of these is specimen size. Four specimen sizes each of one unmodified and two rubber-modified hot-mix asphalt concrete mixes were compacted in the Superpave gyratory compactor to determine the effect of specimen size on compaction and volumetric properties of the mixes. All specimens were compacted using a 150-mm-diameter mold. Specimens of each of the mix types were prepared using three gradations and three binder contents. Densification curves and plotting number of gyrations versus percent of theoretical maximum density were developed for each mix type/gradation/binder content combination. A strong trend in the densification data was observed, in which curves representing specimen sizes of 3500, 5000, and 6500 g were grouped together, apart from the curve representing a 2000-g specimen size. This trend, the grouping of larger specimen data apart from small specimen data, was also observed in volumetric data (optimum asphalt content, voids in mineral aggregate, and voids filled with asphalt). These trends were observed in most of the mix type/ gradation/binder content combinations. The data presented suggest that for specimens of sufficient size, for example, greater than 3500 g, specimen size does not significantly affect the volumetric or compaction properties of hot mix specimens, which supports the ruggedness of the gyratory compaction procedure.

Evaluation of Superpave Gyratory Compaction of Hot Mix Asphalt

1998 ◽  
Vol 1638 (1) ◽  
pp. 111-119 ◽  
Author(s):  
Rajib B. Mallick ◽  
Shane Buchanan ◽  
E. Ray Brown ◽  
Mike Huner
Keyword(s):  
Specific Gravity ◽  
Correction Factor ◽  
Hot Mix Asphalt ◽  
Design System ◽  
Volumetric Properties ◽  
Superpave Gyratory Compactor ◽  
Gyratory Compaction ◽  
Back Calculation ◽  
Crushed Aggregate

The effect of restricted zone on volumetric properties of mixes consisting of all crushed, and all crushed and partially uncrushed, materials was evaluated. For a given aggregate blend, gradations below or above the restricted zone provided higher voids in mineral aggregate (VMA) than mixes through the restricted zone. Mixes with crushed aggregate provided higher VMA than mixes with partially crushed aggregate. It is recommended that further work be conducted to evaluate the effect of different types and shapes of aggregates on the volumetric properties of specimens compacted with the Superpave gyratory compactor. According to the current Superpave mix design system, the bulk specific gravity of a compacted specimen at any gyration is back calculated from the bulk specific gravity determined at Nmaximum and a correction factor determined at Nmaximum. This procedure assumes that the correction factor is constant at all gyrations. A part of this study was carried out to compare the correction factors obtained at different gyration levels during compaction of hot mix asphalt and to evaluate the change in correction factor with gyration levels. Specimens were compacted at different gyration levels, and the bulk specific gravity of each was determined at each gyration level. Bulk specific gravities at each of the gyration levels were also obtained by back calculation from bulk specific gravity at Nmaximum. The correction factor was found to decrease and become close to constant at higher gyration levels. At lower gyrations, densities were found to be greater than those obtained by back calculation. It is recommended that mixes be compacted to Ndesign for determination of design asphalt content.

Sign in / Sign up

Export Citation Format

Share Document