Supervisor/Foreman
PCC Joint and Crack Sealing
Sealant products are used to fill joints (Figures 1 and 2) and cracks in order to prevent entry of water or other non-compressible substances. Although most PCC pavement joints are sealed at the time of new construction, the useful sealant life is limited as stated by the ACPA (2001[1]) on their web site: “A typical hot-pour … Read more
PCC Finishing
Finishing involves all processes and equipment used to create the final surface finish and texture of fresh PCC. Generally, finishing can be divided into floating and texturing: Floating. A flat surface is run across the PCC in order to eliminate high and low spots, embed larger aggregate particles beneath the surface, remove slight imperfections and … Read more
PCC Curing
Curing refers to the maintenance of satisfactory moisture and temperature within a PCC mass as it sets and hardens such that the desired properties of strength, durability and density can develop (PCA, 1988[1]). The desired properties of strength, durability and density are related to the extent of hydration within the PCC mass; the more complete … Read more
PCC Consolidation
Consolidation is the process of making the freshly placed PCC into a more uniform and compact mass by eliminating undesirable air voids and causing it to move around potential obstructions (such as reinforcing steel). Consolidation is usually accomplished using long, slender vibration rods called vibrators. Vibrators work by rotating an eccentric weight which causes the … Read more
Maintenance
The combined effects of traffic loading and the environment will cause every pavement, no matter how well-designed/constructed to deteriorate over time. Maintenance and rehabilitation are what we use to slow down or reset this deterioration process. Maintenance actions, such as crack sealing, joint sealing, fog seals and patching help slow the rate of deterioration by … Read more
Live Bottom Truck
Live bottom (or flo-boy) dump trucks (Figures 1-4) have a conveyor system at the bottom of their bed to unload their payload. HMA is discharged out the back of the bed without raising the bed (Video 1). Live bottom trucks are more expensive to use and maintain because of the conveyor system but they also … Read more
Jointed Plain Concrete Pavement
Jointed plain concrete pavement (JPCP, Figure 1) uses contraction joints to control cracking and does not use any reinforcing steel. Transverse joint spacing is selected such that temperature and moisture stresses do not produce intermediate cracking between joints. This typically results in a spacing no longer than about 6.1 m (20 ft.). Dowel bars are … Read more
Independent Assurance
Independent assurance is the verification by a third party (not directly responsible for quality control or acceptance) of the product and/or the reliability of test results obtained from quality control and acceptance testing. This independent assurance insures that (1) acceptance test results are accurate and provide a fair and equitable basis for construction acceptance and … Read more
HMA Plant Operations
HMA production is the first step in construction. The basic purpose of an HMA plant is to properly proportion, blend, and heat aggregate and asphalt to produce an HMA that meets the requirements of the job mix formula (JMF) (Roberts et al., 1996). There are two basic types of HMA plants commonly in use today: … Read more
HMA Patching
Patches are a common method of treating an area of localized distress. Patches can be either full-depth where they extend from the pavement surface to the subgrade (Figure 1) or partial where they do not extend through the full depth of existing pavement (Figure 2). Full-depth patches are necessary where the entire depth of pavement … Read more
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