Welcome to Pavement Interactive

The online community for all things pavement

The Pavement Interactive functions both as a collaboration space and a ready reference.

Member Login
Lost your password?
Banner 11


Any individual who is responsible for inspecting a paving site or production facility. This work may include quality control and troubleshooting when production problems arise.
Default featured image

General Guidance

  This is an informational resource on hot mix asphalt (HMA). It contains a general overview of all HMA aspects. It is intended to assist those who work with HMA in any way including architects, engineers, contractors, students, and homeowners. Pavement Checklist Pavement Distress Top-Down Cracking References Suggested Reading Asphalt Institute. (2001[1]). HMA Construction. Manual … Read more »

Spalling as a result of a bad construction joint.


Description Cracking, breaking or chipping of joint/crack edges. Usually occurs within about 0.6 m (2 ft.) of joint/crack edge. Problem Loose debris on the pavement, roughness, generally an indicator of advanced joint/crack deterioration Possible Causes Possible causes are (AASHTO, 1993[1]): Excessive stresses at the joint/crack caused by infiltration of incompressible materials and subsequent expansion (can also … Read more »

Faulting - looking in the opposite direction of traffic flow.


Description A difference in elevation across a joint or crack usually associated with undoweled JPCP. Usually the approach slab is higher than the leave slab due to pumping, the most common faulting mechanism. Faulting is noticeable when the average faulting in the pavement section reaches about 2.5 mm (0.1 inch). When the average faulting reaches 4 … Read more »

BST bleeding in the wheelpaths


Description A film of asphalt binder on the pavement surface. It usually creates a shiny, glass-like reflecting surface (as in the first photo) that can become quite sticky. Sometimes referred to as “flushing”. Problem Loss of skid resistance when wet Possible Causes Bleeding occurs when asphalt binder fills the aggregate voids during hot weather and then expands … Read more »


Construction Noise

Noise Basics Healthy humans can hear audible sound with a range of 20 Hz to 20,000 Hz with a maximum intensity at 3,000 Hz. (Hz = Hertz, or cycles per second.) Frequencies below 20 Hz are called “infrasound” and above 20,000 Hz “ultrasound.” The numerical magnitude of a sound typically expressed as sound pressure level … Read more »

Figure 1: HMA temperature vs. compaction aspects.

Factors Affecting Compaction

HMA compaction is influenced by a myriad of factors; some related to the environment, some determined by mix and structural design and some under contractor and agency control during construction (Table 1).   Table 1: Factors Affecting Compaction Environmental Factors Mix Property Factors Construction Factors Temperature Ground temperature Air temperature Wind speed Solar flux Aggregate … Read more »

Figure 1. Truck loading under a storage silo.

HMA Transport

Mix transport involves all actions and equipment required to convey HMA from a production facility to a paving site including truck loading, weighing and ticketing, hauling to the paving site, dumping of the mix into the paver or material transfer vehicle hopper, and truck return to the HMA production facility (Roberts et al., 1996[1]). Ideally, … Read more »

Default featured image

HMA Placement Considerations

There are, of course, many considerations to take into account when placing HMA. Many are dependent upon local materials, weather, crew knowledge and training, and individual experience. This subsection presents a few of the basic considerations that apply in virtually all situations: Lift thickness. A “lift” refers to a layer of pavement as placed by … Read more »

Default featured image

HMA Placement

Mix placement and compaction are the two most important elements in HMA pavement construction. Mix placement involves any equipment or procedures used to place the delivered HMA on the desired surface at the desired thickness. Mix placement can involve complicated asphalt paver operations or simple manual shoveling. This section provides a basic description of HMA … Read more »


Compaction Measurement and Reporting

Compaction reduces the volume of air in HMA. Therefore, the characteristic of concern is the volume of air within the compacted pavement. This volume is typically quantified as a percentage of air voids by volume and expressed as “percent air voids”. Percent air voids is calculated by comparing a test specimen’s bulk density with its … Read more »

Page 1 of 1512345...10...Last »