Page 17 - LWFC Catalog

aircraft is expected to sink into the lightweight, crushable material, and the aircraft is decelerated
as it rolls through the material. As the core material of the current EMAS, cellular concrete (CC)
exhibits a superior absorbing energy capability. While the design of CC could significantly impact
the energy absorption and impact resistance of the material, which could lead to very different
aircraft arresting effectiveness, there is yet a comprehensive study to evaluate the performance
of CC under penetration or impact. The paper presents an in-depth study on the behavior of
CC under the compressibility, penetration, and impact tests. The effect of pore content, pore
structure, and fiber content on CC mechanical properties and energy absorption capacity were
evaluated. The results from this study will provide critical information for a more efficient EMAS
design.

1PM - First Use of PLDCC in Florida: West Eloise Loop Road Permeable Low-Density Cellular Concrete
1:50PM (PLDCC) was used to construct a road over a peat layer near Winter Haven, Florida. A section of
the roadway on a narrow strip of land between two lakes has a long history of settlement due to
a thick (up to 13 feet) organic/peat deposit beneath the roadway. Additional pavement layers
added over the years simply added more weight to the road, causing additional settlement. As
a result, water sometimes covers the road during the wet season, causing temporary closures and
rerouting of traffic. The bottom of the deepest pavement layer was about 4 feet below the current
surface! The authors designed a program to remove about 3 feet of asphalt, limerock base and
embankment soil, to be replaced with permeable low density cellular concrete (PLDCC, density
of 30 pcf). This material replacement unloaded the underlying organic soil which and allowed
raising the elevation of the road by 18 inches without adding any new soil loads (i.e., minimal
future settlement expected). The use of permeable (versus impermeable) cellular concrete
eliminated the need for cross-drains and also helps to minimize buoyancy for when water levels
are high. Although the total pavement weight was sufficient to hold down the buoyant lightweight
fill, helical anchors were installed to help hold down the pavement during high water conditions
for an additional level of safety.