Challenge

The Orange County Solid Waster Transfer Station on McLeod Road is one of only two solid waste facilities that serve the city of Orlando in Florida. Originally built in 1960, by 2019 this facility was no longer able to efficiently process the nearly 170,000 tons of trash it received annually. Given the state of this facility, in February 2019 Orange County was awarded $26 million to build a new, cutting-edge facility.

Solution

After demolition of the existing structure. A 17,500 sq ft area, outside of the footprint of the original building, required a lighter material, due to differential settlement concerns. Antillian Engineering chose to utilize a lightweight, low-density cellular concrete (LDCC) as a backfill material, in those areas. The LDCC material was designed to be placed outside the footprint of the original building. The LDCC material is extremely lightweight, yet also features a higher compressive strength, when compared to compacted fill dirt material. The strength and weight can be changed for specific needs. A 30 PCF wet mix design was chosen for the project, which yields a minimum 140 psi compressive strength, with a dry weight of 50 pounds pcf. Three low-density cellular concrete installers - LRE Ground Services, CellFill and SiteMix - collaborated on this project to ensure optimal and efficient product delivery and project completion. The six-person crew installed 6,600 cubic yards of Aerix Industries’ non-permeable, 30-pcf Aerlite-iX™ LDCC at an average rate of 175 cubic yards per hour. The LDCC was placed using four-foot lifts at a maximum height of eight feet. The remainder of the fill utilized, was compacted fill dirt to the finished slab elevation.

Project Summary

Geotechnical Engineer: Kokolakis Contracting

Engineer of Record: Antillian Engineering

LDCC Contractor: LRE Commercial

Specialty Engineer: Madrid engineering

Foam Supplier: Aerix Industries - Aerlite-iX Material

LDCC material being poured

Pouring of LDCC

LDCC material being placed

Fill dirt being placed atop LDCC