Page 21 - LWFC Catalog
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4PM -     Laboratory Study on Pullout Capacities of Steel and Geogrid Reinforcements in Lightweight
      4:50 PM    Cellular Concrete Fill Lightweight cellular concrete (LCC) fill has been increasingly used as a
                 backfill material for mechanically-stabilized earth (MSE) walls, which may include steel or geogrid
                 reinforcement layers. Design of MSE walls with these reinforcement layers requires checking their
                 pullout capacities in the LCC fill against pullout forces during construction and service of the
                 walls. Limited pullout tests have been performed so far to evaluate pullout capacities of steel and
                 geogrid reinforcement layers in LCC fill. This presentation will discuss the design and preparation of
                 pullout specimens, the pullout test procedure, the failure modes, the pullout results under different
                 normal stresses, curing ages, and with cold joints, and comparisons of pullout capacities of steel
                 reinforcement versus geogrid reinforcement.  The pullout box used in this study is 5 ft long, 2 ft
                 wide, and 2 ft high.

       5PM -     Static and Dynamic Properties of Lightweight Cellular  Concrete  The  use  of  lightweight
      5:50PM     cellular  concrete  (LCC)  requires  an  understanding  of  both  its  static  and  dynamic  properties
                 and the associated behaviors, which were evaluated in this experimental study. The extensive
                 laboratory testing program was conducted on LCC materials with four different density values.
                 Results yielded the shear strength parameters, coefficients of permeability, at-rest earth pressure
                 coefficients, the maximum shear moduli along with the reduction in the normalized shear modulus
                 with strain and the damping ratio and its variation with strain were determined. LCC material
                 density strongly influenced the unconfined compressive strength and undrained shear strength
                 parameters of partially saturated samples, while it had little to no effect on the effective shear
                 strength  parameters  of  the  saturated  materials,  the  at-rest  earth  pressure  coefficient  and  the
                 Poisson’s ratio. The maximum shear moduli and the reduction in normalized shear modulus with
                 shear strain were both found to depend on both the LCC material density and the effective normal
                 stress. Damping ratios were found to decrease with an increase in shear strain to a threshold
                 shear strain beyond which they were found to increase reaching a similar damping ratio under a
                 constant effective normal stress regardless of density.


       5PM -     Ultra-Lightweight Foamed Glass Aggregate: A Green Choice for Resilient Construction
      5:50PM     Ultra-lightweight  foamed  glass  aggregate  (UL-FGA)  is  a  lightweight  fill  and  insulation  material
                 that is manufactured from recycled container glass.  While UL-FGA is relatively new to the U.S.
                 marketplace, it has a history of use in Europe for over 25 years.  Closed-cell UL-FGA is a good load-
                 bearing layer and is non-absorptive and non-reactive. The applications for UL-FGA are vast and
                 include embankment construction over soft or sensitive soils or utilities, lightweight backfill for earth
                 retaining systems, insulation and drainage around the building envelope, and water storage in
                 stormwater management systems. There is an emerging trend to evaluate the sustainability of
                 projects from design through construction and maintenance, and material selection can greatly
                 influence the realization of project goals.  Life cycle analysis metrics for UL-FGA will be reviewed
                 and a detailed description will be shared of how used glass bottles and jars are recycled into UL-
                 FGA. Lastly, two case studies where UL-FGA was used as a lightweight storage layer for stormwater
                 will be presented.
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