There are three pavement types: Flexible – Asphalt concrete Rigid – Portland cement concrete Interlocking pavers – Stone, brick, or blocks But there are seemingly infinite variations of each. Flexible: The black stuff is asphalt concrete (left photo), also called hot-mix asphalt concrete. In some states or regions, it is […]
Portland cement concrete (PCC) is primarily a composition of Portland cement, water, rock, and sand. Portland cement is manufactured by grinding limestone, iron ore and/or fly ash into a powder and feeding into a rotary kiln at 2,700 degrees Fahrenheit. Not unlike the residue of a coal furnace, clinkers are […]
Producing hot mix asphalt concrete is an energy intensive process involving heating aggregate up to 435 degrees F, then mixing in asphalt cement and recycled materials. Typical recyclables are asphalt concrete removed from older pavements & garbage, asphalt shingles, plastic and glass. So, the plant site shown has a stockpile of aggregate […]
I was at dinner (outside because of Covid). The restaurant had a unique barrier to protect the dining tent. It is a portable vehicle barrier from Pitagone and distributed by ARX Perimeters. It is a product from Belgium and appears to be bad ass.There is no anchoring involved. An intruding vehicle hits the barrier, […]
Hot mix asphalt concrete (abbreviated as HMA or HMAC) is a thermoplastic mixture of asphalt cement, rock and sand. In some states the mixture is called bituminous concrete. The earliest asphalt roads were called Macadam, after a Scottish engineer, John McAdam. He created a road building method in the early 1800s […]
The Pavement Condition Index (PCI) is the most important element of determining pavement conditions. It is at the heart of the Zimmer approach to managing pavements. The PCI was developed at the Corps of Engineer’s Construction Engineering Research Laboratory (CERL) in Champaign, Illinois by my friends, Mo Shahin, PhD. and […]
What we mean by a subjective approach is a property manager will rate or prioritize pavement conditions visually or with a seat of the pants approach. Rating is made by what looks worse or how uncomfortable the ride is. With pavement management, a subjective approach can work on a single, small property […]
Below is a really good figure of the equipment used in the surface milling/recycling/paving process. It was produced by The Wirtgen Group. They manufacture milling machines, crushers, hot mix asphalt plants, pavers, and compactors, like a vertically integrated conglomerate. Interestingly, Wirtgen is a corporate subsidiary of the John Deere Company. […]
A common approach to repairing a pavement pothole is to fill the void with asphalt concrete. If there are only a few potholes, a few bags of cold patch material from the local builder’s supply store can be use to fill the holes. Here are some tips that will make […]
This cute dimple in the pavement is a sign of a future maintenance problem so be sure to keep an eye out and for it to worsen. Experience tells us that a cavity has formed under the pavement surface layer, likely because subsurface water is carrying fine soil and rock […]