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It’s not every day strict environmental regulations result in a pilot project that proves green product technology that has the capability further down the road to save the project owner tens of millions of dollars and gives the opportunity to fully convert a construction program over to use of recycled and sustainable materials. During the early stages of construction of the Pier 400 Project at the Port of Los Angeles, the U.S. Fish & Wildlife Service (USF&WS) was concerned that an endangered species of bird, the Least Tern, had adopted the Pier 400 construction site as a nesting ground. Consequently, all materials selected to be used on the construction site during this beginning stage of the project, were reviewed by USF&WS for environmental acceptability before applying in proximity to an endangered species nesting ground. The port engineering staff specified the EMC SQUARED System stabilizer product, a non-toxic product with a well-established track record of effectively stabilizing aggregate materials for road running surface applications, to be used in combination with recycled aggregate materials stockpiled on site, for construction of the access road to the project site. The stabilized aggregate layer was designed with an environmentally friendly resin emulsion armor coat spray applied to the finished surface to help protect the surface of the stabilized layer and provide dust control.
This construction haul road would support all the trucking and heavy equipment traffic during the early phase of the massive Pier 400 expansion, a project with a total construction dollar value of almost $800 million. While the stabilized aggregate materials could have been prepared in a mixing plant and placed by asphalt paving machine, the stabilizer product was applied using relatively unsophisticated in-place mixing and a motor grader for shaping the finished surface of the road. In spite of the fact that the stabilized aggregate layer was designed to be only six inches thick, which is a relatively thin layer for servicing heavy trucks and construction equipment traffic, this super low cost pavement material held up without a problem under all construction traffic for two and a half years. In anticipation of a traffic increase beyond the 400-600 trucks per day that the six-inch aggregate layer served, the road structural section was later increased by the addition of four inches of hot mix asphalt. The construction engineer in charge of the paving work commented that the EMC SQUARED stabilized aggregate running surface was still in such good condition that cleaning the surface with a power broom was the only prep-work required before placing the asphalt surface course. Engineers visiting this road while it was in service commented that it looked like the road was paved with a flexible concrete surfacing, as it had an appearance much like concrete, but without any joints or cracks. Now, placed in perspective with the Dynamic Modulus and Repeated Load Triaxial test results from a pavement materials laboratory that demonstrate the outstanding pavement performance of EMC SQUARED Stabilized Aggregate materials, this Port of Los Angeles pilot project on the Pier 400 access road makes perfect sense. There is good reason that the stabilized aggregate performed like a high strength flexible pavement material. That’s exactly what it was.