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Marshall mix design primarily address the determination of asphalt binder content, while Superpave addresses all element of mix design. The Marshall design/construction method requires in most cases compaction 95% or greater of the maximum lab value.

What is the difference between Marshall mix and Superpave?

Marshall mix design primarily address the determination of asphalt binder content, while Superpave addresses all element of mix design. The Marshall design/construction method requires in most cases compaction 95% or greater of the maximum lab value.

What is asphaltic cement?

Asphalt (sometimes called “liquid asphalt”, “asphalt cement” or “asphalt binder”) is a sticky, black and highly viscous liquid or semi-solid form of petroleum. It may be found in natural deposits or may be a refined product; it is a substance classed as a pitch.

What does Superpave stand for?

Superpave is an acronym which stands for: Superior Performing Asphalt Pavements. Superpave is a performance-related asphalt binder and mixture specification.

What is Superpave binder?

A New Approach to Asphalt Mix Design Rather than a specific process or procedure, Superpave is a performance-based specification for asphalt binder and volumetric mixture design. … A system of classifying asphalt binder based on its performance response to temperatures and aging characteristics.

Is Superpave an HMA?

Superpave consists of (1) an asphalt binder specification, (2) an HMA mix design method and (3) HMA tests and performance prediction models. Each one of these components is referred to by the term “Superpave”.

When was Superpave created?

After five years of intensive research and testing, SHRP introduced the Superpave system in 1992.

What is Superpave testing?

Overview. The Superpave Shear Tester (SST) (Figure 1) is used to characterize a HMA mixture’s resistance to permanent deformation (rut resistance). … Results from the RSCH test are used to determine the accumulation of permanent shear strain with load repetitions.

What pavement distress is evaluated by the Superpave testing?

Using the Superpave system, materials and mixes can be designed to reliably perform under any conditions of load and environment. It evaluates the binders’ abilities in resisting rutting, fatigue and low temperature cracking based on their rheological properties at the anticipated pavement temperatures.

What is asphaltic concrete pavement?

Asphalt Concrete is a composite material commonly used in construction of roads, highways, airports, parking lots, and many other types of pavement. It is commonly called simply asphalt or blacktop. … To the layperson Asphalt Concrete pavements is most often called just “asphalt“.

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What is HMA pavement?

Asphalt pavement refers to any paved road surfaced with asphalt. Hot Mix Asphalt (HMA) is a combination of approximately 95% stone, sand, or gravel bound together by asphalt cement, a product of crude oil. Asphalt cement is heated aggregate, combined, and mixed with the aggregate at an HMA facility.

Is asphalt and bitumen same?

Asphalt is a composite of aggregates, sand, and bitumen; where bitumen acts as a liquid binding material that holds asphalt together. … To make things simple, we can relatively say asphalt is concrete (mixture) while bitumen is cement (binder) for pavements.

How does the Superpave binder specification related to performance?

SHRP research developed the Superpave binder specification to be generic, performance based and climate driven. It addresses the pavement distresses of rutting, fatigue, and thermal cracking. Complete testing requires a lengthy process in person-hours and elapsed time.

What is Superpave 19?

Superpave 19.0 Binder course mix for Traffic Category A, B, C, D, and E roads. Superpave 19.0 is similar to the traditional HL 4, HL 8, and (HS) HL 8 mixes according to OPSS 1150. Superpave 25.0 Large stone binder course mixes for use when thicker binder course lifts are required.

What grade PG is needed for 98 reliability?

The common minimum reliability used is 98%, so that means when the PG 64-10 binder is selected, the asphalt binder in the AC pavement should perform satisfactorily under normal traffic condition at the location where the extreme pavement temperature are within the range of −10°C and 64°C throughout its service life …

What is 19mm asphalt?

Asphalt Paving ‐ 19mm Binder Course 19mm Binder Course is applied in one layer, is as strong as regular base and has a sufficient amount of liquid asphalt to roll into a very durable surface. The difference is that the texture is coarser than 9.5mm Wearing Course.

What is dust to binder ratio?

During design, mixtures that are above the maximum density line at the 2.36-mm (for 19-mm or smaller mixtures) or 4.75-mm (for 25-mm or larger mixtures) critical sieve should have a dust-to-binder ratio of no more than 1.4.

What is Marshall mix design?

The Marshall Mix Design method was originally developed by Bruce Marshall of the Mississippi Highway Department in 1939. The main idea of the Marshall Mix Design method involves the selection of the asphalt binder content with a suitable density which satisfies minimum stability and range of flow values.

What is Superpave Gyratory compactor?

Superpave Gyratory Compactor by Pine Instruments prepares hot-mix asphalt specimens for Superpave mix design operations and is made in the USA. A mold with an asphalt specimen is gyrated on its longitudinal axis at a fixed angle while the end platens are held parallel. Mold Assemblies are sold separately.

What are the benefits of gyratory compaction?

Results indicate that samples compacted with the gyratory compactor show higher precision in the strength test than the impact hammer. Data show that gyratory compaction results in different engineering properties than those obtained from the impact hammer compaction.

What is the angle of the laboratory compaction mold in the Superpave Gyratory compactor?

The compactor tilts the specimen molds at an internal angle of 1.16 ± 0.02° (20.2 ± 0.35 mrad) and gyrates specimen molds at a rate or 30.0 ± 0.5 gyrations per minute throughout compaction.

What does Rice mean in asphalt?

The Rice Test for Specific Gravity of Asphalt is a common test that measures the Theoretical Maximum Specific Gravity (Gmm) of asphalt specimens. The test is an integral part of the quality assurance of asphalt mixtures. Free and entrapped air is removed from the asphalt sample to prepare for the test.

What is PG grade?

Superpave performance grading (PG) is based on the idea that an HMA asphalt binder’s properties should be related to the conditions under which it is used. … For asphalt binders, this involves expected climatic conditions as well as aging considerations.

What's the density of asphalt?

Standard density for asphalt is 145 lb/ft3 (2322 kg/m3). Multiply the volume by the density (in the same units) to get the weight.

What is DSR test?

Determination of complex shear modulus and. phase angle – Dynamic Shear Rheometer (DSR) Overview. The test is used to determine the complex shear modulus, G*, and the phase angle, δ, of bitumen and bituminous binders under oscillating stress at different temperatures.

What is PG in pavement?

General Description of Performance Grade (PG) Bitumen Performance Grade (PG) Bitumen is bitumen which is graded based on its performance at different temperatures. … From this, the highest and the lowest temperatures of the pavement are calculated and the bitumen that performs well in that temperature range is selected.

What is performance grade asphalt binder?

The Performance Grade (PG) system is the method of categorizing an asphalt cement binder. used in asphalt pavement relative to its rated performance at different temperatures. It was. originally developed during the Strategic Highway Research Program (SHRP) in the early. 1990’s and was called “SuperPave.

What is Aashto m320?

AASHTO M 320, 2021 Edition, 2021 – Standard Specification for Performance-Graded Asphalt Binder. This specification covers asphalt binders graded by performance. Grading designations are related to the average seven-day maximum pavement design temperature and the minimum pavement design temperature.

Which property is most important for asphalt binder?

Typically, the most important physical properties are: Durability. Durability is a measure of how asphalt binder physical properties change with age (sometimes called age hardening). In general, as an asphalt binder ages, its viscosity increases and it becomes more stiff and brittle.

What pg64 22?

Paving Asphalt PG 64-22 is a Performance Graded (PG) asphalt derived from specially selected crude oils via carefully controlled refining processes. The quality of ExxonMobil products is assured for every delivery. Products are manufactured according to global product integrity requirements.

What are the components of asphaltic concrete?

Asphalt concrete is a combination of two primary ingredients: (i) aggregate and (ii) asphalt cement. Typically, the aggregate constitutes 90–95% (w/w) of the total mixture and the asphalt cement (asphalt binder) constitutes 5–10% (w/w) of the total mixture to form the asphalt concrete.