https://pavementinteractive.org/ New and updated articles from Pavement Interactive, the free pavement engineering reference published by HeadLight. en-us Sun, 01 Nov 2026 00:00:00 GMT https://pavementinteractive.org/reference-desk/testing/cement-tests/air-content-of-fresh-concrete/ https://pavementinteractive.org/reference-desk/testing/cement-tests/air-content-of-fresh-concrete/#2026-11-01 Sun, 01 Nov 2026 00:00:00 GMT Testing Why air is entrained in paving concrete and how it is measured in the field with the pressure meter, the volumetric meter and the gravimetric method. https://pavementinteractive.org/reference-desk/testing/soil-tests/atterberg-limits/ https://pavementinteractive.org/reference-desk/testing/soil-tests/atterberg-limits/#2026-11-01 Sun, 01 Nov 2026 00:00:00 GMT Testing The liquid limit, plastic limit and plasticity index: what they mean for a fine-grained soil, how the cup and thread tests work, and the one-point method. https://pavementinteractive.org/reference-desk/maintenance-and-rehabilitation/maintenance/bituminous-surface-treatments/ https://pavementinteractive.org/reference-desk/maintenance-and-rehabilitation/maintenance/bituminous-surface-treatments/#2026-11-01 Sun, 01 Nov 2026 00:00:00 GMT Maintenance & Rehabilitation A bituminous surface treatment (BST), also known as a seal coat or chip seal, is a thin protective wearing surface that is applied to a pavement or base course. BSTs can provide all of the following: https://pavementinteractive.org/reference-desk/construction/placement/building-smooth-pavements/ https://pavementinteractive.org/reference-desk/construction/placement/building-smooth-pavements/#2026-11-01 Sun, 01 Nov 2026 00:00:00 GMT Construction Building a smooth pavement means accurate grade control, steady paving without stops, automatic screed controls and careful truck exchanges. https://pavementinteractive.org/reference-desk/construction/compaction/cold-weather-paving/ https://pavementinteractive.org/reference-desk/construction/compaction/cold-weather-paving/#2026-11-01 Sun, 01 Nov 2026 00:00:00 GMT Construction Compaction is of special concern during cold weather paving because as ambient temperatures decrease, HMA cool-down rates increase and the time available for compaction (before cessation temperature is reached) is reduced. https://pavementinteractive.org/reference-desk/testing/cement-tests/concrete-batch-tickets-and-the-water-cementitious-ratio/ https://pavementinteractive.org/reference-desk/testing/cement-tests/concrete-batch-tickets-and-the-water-cementitious-ratio/#2026-11-01 Sun, 01 Nov 2026 00:00:00 GMT Testing Reading a ready-mixed concrete batch ticket, checking time and drum revolutions, and working out the w/cm and the water that may still be added on site. https://pavementinteractive.org/reference-desk/qc-qa/quality-assurance/construction-inspection/ https://pavementinteractive.org/reference-desk/qc-qa/quality-assurance/construction-inspection/#2026-11-01 Sun, 01 Nov 2026 00:00:00 GMT QC & QA Construction inspection is the observation, testing and documentation of road work to confirm it follows the plans and specifications. https://pavementinteractive.org/reference-desk/maintenance-and-rehabilitation/maintenance/crack-seals/ https://pavementinteractive.org/reference-desk/maintenance-and-rehabilitation/maintenance/crack-seals/#2026-11-01 Sun, 01 Nov 2026 00:00:00 GMT Maintenance & Rehabilitation Crack seal products are used to fill individual pavement cracks to prevent entry of water or other non-compressible substances such as sand, dirt, rocks or weeds. https://pavementinteractive.org/reference-desk/pavement-management/pavement-evaluation/deflection-based-nondestructive-pavement-analyses/ https://pavementinteractive.org/reference-desk/pavement-management/pavement-evaluation/deflection-based-nondestructive-pavement-analyses/#2026-11-01 Sun, 01 Nov 2026 00:00:00 GMT Pavement Management This topic will be oriented toward techniques which can be used to interpret nondestructive testing, NDT, data from the Falling Weight Deflectometer, FWD. https://pavementinteractive.org/reference-desk/pavement-types-and-history/pavement-types/dowel-bar/ https://pavementinteractive.org/reference-desk/pavement-types-and-history/pavement-types/dowel-bar/#2026-11-01 Sun, 01 Nov 2026 00:00:00 GMT Pavement Types and History Dowel bars are short steel bars that provide a mechanical connection between slabs without restricting horizontal joint movement. https://pavementinteractive.org/reference-desk/design/design-parameters/drainage/ https://pavementinteractive.org/reference-desk/design/design-parameters/drainage/#2026-11-01 Sun, 01 Nov 2026 00:00:00 GMT Design Proper drainage is important to ensure a high quality long lived pavement; moisture accumulation in any pavement structural layer can cause problems. https://pavementinteractive.org/reference-desk/construction/site-preparation/embankment-and-base-compaction-control/ https://pavementinteractive.org/reference-desk/construction/site-preparation/embankment-and-base-compaction-control/#2026-11-01 Sun, 01 Nov 2026 00:00:00 GMT Construction How embankment, subgrade and base compaction is controlled: lifts, moisture conditioning, rollers, test frequency, proof rolling and when to retest. https://pavementinteractive.org/reference-desk/materials/asphalt/emulsified-asphalt/ https://pavementinteractive.org/reference-desk/materials/asphalt/emulsified-asphalt/#2026-11-01 Sun, 01 Nov 2026 00:00:00 GMT Materials Emulsified asphalt is simply a suspension of small asphalt cement globules in water, which is assisted by an emulsifying agent (such as soap). https://pavementinteractive.org/reference-desk/construction/site-preparation/existing-surface-preparation-for-overlays/ https://pavementinteractive.org/reference-desk/construction/site-preparation/existing-surface-preparation-for-overlays/#2026-11-01 Sun, 01 Nov 2026 00:00:00 GMT Construction Overlays (either structural or non-structural) make up a large portion of the roadway paving done today. The degree of surface preparation for an overlay is dependent on the condition and type of the existing pavement. https://pavementinteractive.org/reference-desk/testing/soil-tests/field-density-of-soils/ https://pavementinteractive.org/reference-desk/testing/soil-tests/field-density-of-soils/#2026-11-01 Sun, 01 Nov 2026 00:00:00 GMT Testing Measuring in-place density and moisture of soils and base with the nuclear gauge and sand cone, then percent compaction and the oversize correction. https://pavementinteractive.org/reference-desk/testing/cement-tests/field-testing-of-fresh-concrete/ https://pavementinteractive.org/reference-desk/testing/cement-tests/field-testing-of-fresh-concrete/#2026-11-01 Sun, 01 Nov 2026 00:00:00 GMT Testing The routine tests on fresh concrete at the truck or paver: sampling, temperature, slump, air, unit weight and strength specimens, and their timing. https://pavementinteractive.org/reference-desk/maintenance-and-rehabilitation/maintenance/hma-patching/ https://pavementinteractive.org/reference-desk/maintenance-and-rehabilitation/maintenance/hma-patching/#2026-11-01 Sun, 01 Nov 2026 00:00:00 GMT Maintenance & Rehabilitation Patches are a common method of treating an area of localized distress. https://pavementinteractive.org/reference-desk/pavement-types-and-history/pavement-types/hma-pavement/ https://pavementinteractive.org/reference-desk/pavement-types-and-history/pavement-types/hma-pavement/#2026-11-01 Sun, 01 Nov 2026 00:00:00 GMT Pavement Types and History HMA pavements are classified as "flexible" pavements because the total pavement structure deflects, or flexes, under loading. A flexible pavement structure is typically composed of several layers of material. https://pavementinteractive.org/reference-desk/pavement-types-and-history/pavement-types/hma-recycling/ https://pavementinteractive.org/reference-desk/pavement-types-and-history/pavement-types/hma-recycling/#2026-11-01 Sun, 01 Nov 2026 00:00:00 GMT Pavement Types and History HMA is one of the most recycled products in the U.S. It is estimated that about 90 million tons of recycled HMA (termed "reclaimed asphalt pavement" or RAP) is used each year in the U.S. https://pavementinteractive.org/reference-desk/construction/transportation/hma-transport/ https://pavementinteractive.org/reference-desk/construction/transportation/hma-transport/#2026-11-01 Sun, 01 Nov 2026 00:00:00 GMT Construction 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… https://pavementinteractive.org/reference-desk/construction/compaction/intelligent-compaction/ https://pavementinteractive.org/reference-desk/construction/compaction/intelligent-compaction/#2026-11-01 Sun, 01 Nov 2026 00:00:00 GMT Construction Intelligent compaction is a roller-mounted system of sensors, GPS and software that measures, maps and records compaction in real time. https://pavementinteractive.org/reference-desk/testing/asphalt-tests/intermediate-temperature-cracking-tests/ https://pavementinteractive.org/reference-desk/testing/asphalt-tests/intermediate-temperature-cracking-tests/#2026-11-01 Sun, 01 Nov 2026 00:00:00 GMT Testing IDEAL-CT and I-FIT: quick room-temperature cracking tests on asphalt mixture, used in balanced mix design and production, and what their indexes mean. https://pavementinteractive.org/reference-desk/materials/aggregate/introduction/ https://pavementinteractive.org/reference-desk/materials/aggregate/introduction/#2026-11-01 Sun, 01 Nov 2026 00:00:00 GMT Materials Aggregate" is a collective term for the mineral materials such as sand, gravel and crushed stone that are used with a binding medium (such as water, bitumen, portland cement, lime, etc.) to form compound materials (such as asphalt… https://pavementinteractive.org/reference-desk/construction/compaction/introduction/ https://pavementinteractive.org/reference-desk/construction/compaction/introduction/#2026-11-01 Sun, 01 Nov 2026 00:00:00 GMT Construction Compaction is the process by which the volume of air in an HMA mixture is reduced by using external forces to reorient the constituent aggregate particles into a more closely spaced arrangement. https://pavementinteractive.org/reference-desk/maintenance-and-rehabilitation/rehabilitation/introduction/ https://pavementinteractive.org/reference-desk/maintenance-and-rehabilitation/rehabilitation/introduction/#2026-11-01 Sun, 01 Nov 2026 00:00:00 GMT Maintenance & Rehabilitation The combined effects of traffic loading and the environment will cause every pavement, no matter how well-designed/constructed to deteriorate over time. https://pavementinteractive.org/reference-desk/pavement-management/analysis/life-cycle-assessment/ https://pavementinteractive.org/reference-desk/pavement-management/analysis/life-cycle-assessment/#2026-11-01 Sun, 01 Nov 2026 00:00:00 GMT Pavement Management The International Organization of Standardization (ISO) wrote guidelines for life cycle assessment. https://pavementinteractive.org/reference-desk/pavement-management/analysis/life-cycle-cost-analysis/ https://pavementinteractive.org/reference-desk/pavement-management/analysis/life-cycle-cost-analysis/#2026-11-01 Sun, 01 Nov 2026 00:00:00 GMT Pavement Management All new construction, reconstruction, rehabilitation and maintenance projects should employ some level of economic evaluation to determine the most cost effective method and timing. https://pavementinteractive.org/reference-desk/design/design-parameters/loads/ https://pavementinteractive.org/reference-desk/design/design-parameters/loads/#2026-11-01 Sun, 01 Nov 2026 00:00:00 GMT Design One of the primary functions of a pavement is load distribution. Therefore, in order to adequately design a pavement something must be known about the expected loads it will encounter. https://pavementinteractive.org/reference-desk/construction/placement/longitudinal-joint-construction/ https://pavementinteractive.org/reference-desk/construction/placement/longitudinal-joint-construction/#2026-11-01 Sun, 01 Nov 2026 00:00:00 GMT Construction A longitudinal joint is the interface between two adjacent and parallel HMA mats. https://pavementinteractive.org/reference-desk/testing/cement-tests/making-and-curing-concrete-test-specimens/ https://pavementinteractive.org/reference-desk/testing/cement-tests/making-and-curing-concrete-test-specimens/#2026-11-01 Sun, 01 Nov 2026 00:00:00 GMT Testing Making cylinders and beams in the field, initial curing on site, transport and final curing, and the handling errors that most often cause low strength results.