RAPID REPAVING OF I-495

Francis O. Day Co., Inc. placed Stone Matrix Asphalt on a 2.2 mile stretch of the inner and outer loops of the beltway, utilizing more than 20,000 tons of SMA. The job entailed placing a surface course on four lanes in each direction, plus acceleration and deceleration lanes and shoulders. The SMA quantity totaled some 20,000 tons - 10,000 tons per four-lane side.

The contractor proposed paving the project in just two weekends. It came down to a choice between doing the project in small amounts with periodic lane closures over an extended period of time or, the contractor could get all of the work done if they took lanes out of service for three nights on each of two weekends. Maryland accepted the contractor’s idea of extended lane closures on two weekends - and it worked perfectly. “We did it through partnering with the State, which seemed to be very successful for us and for them,” said Steve Sutter, General Manager for the company’s southern Maryland region.

The project manager estimated it would have taken 20 to 24 night shifts, working from 10 p.m. to 5 a.m. to accomplish the project. This was due to the time taken to set out lane closures, compact the asphalt, stripe the pavement and pick up the lane closures. Highway officials said the two weekend system had three advantages: less traffic disruption, lower costs since less traffic control was needed, and higher quality. Completing the project in two weekends minimizes the exposure of partially finished pavements for traffic. When new pavement edges don’t take a prolonged beating from traffic, the quality of the longitudinal joints is also improved.

All pavement milling was completed ahead of the paving operation. Dixie Construction removed 2 inches of existing asphalt from the beltway.

Each side of the beltway was paved in the same sequence. One weekend’s work preceded the Fourth of July and the other followed it. The first shifts work began on Friday at 8 p.m. and finished at 11:00 Saturday morning. “On Friday night we paved the 6 foot inside shoulder and lanes 1 and 2, which make up a 30 foot mat,” say Sutter. “We did that with two pavers, one running 18 feet wide, the second one 12 feet wide. We did 4,500 tons on Friday night on both sides of the project.”

On Saturday night, Francis O. Day Co., Inc. paved the two outside lanes with two pavers, each running 12 feet wide. Working from 8 p.m. Saturday till 11 a.m. Sunday, production reached 3,500 tons. “Then on Sunday night we did the outside shoulder and ramps” said Sutter. “We used two pavers, and paving widths varied from very narrow widths to 20 feet” On the Sunday night shift, which ended at 1 a.m. Monday, the crews placed some 2,000 tons. The total for three shifts: 10,000 tons. In a more conventional paving operation, placing 2,000 tons of SMA per shift would be considered an excellent production rate.

Just getting hot mix to the job was a challenge, the trucks had to haul asphalt through all of the traffic approaching the work zone. “We over-trucked it by four to five trucks for a comfort factor, to make sure that the pavers never stopped” said Sutter. On Friday nights, the contractor started with 46 trucks, on Saturday nights, 40 trucks and on Sunday nights, 28 trucks.

Francis O. Day Co., Inc. used two material transfer vehicles (MTVs). Each vehicle could hold 20 to 30 tons. They improved production, and they gave F.O. Day Co., Inc. a non-stop paving operation which enhanced smoothness of the pavement. If trucks were slowed by traffic, the MTVs would keep the pavers moving with the material they had in storage. Six rollers compacted the two inches of SMA behind the two pavers. Back-up pavers and rollers were kept onsite and a significant pavement project was completed with minimal traffic disruption.