Page 17 - LWFC Catalog
P. 17

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.
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