Improved systems, apparatus and methods for construction of slurry walls are provided. A sheet piling barrier is installed into a slurry wall construction to provide improved fluid barrier capability and/or structural integrity. A void creation device allows removal of cementitious material from around the engagement lock element of an installed sheet piling member to prevent interference with engagement of the engagement lock element of a subsequently installed sheet piling member after hardening of the slurry wall.

A friction reducing jacket is applied to a pile. The jacket comprises a sheet material and is formed in a shape that can conform to the exterior surface of the pile. The sheet material comprises a thermoplastic, e.g., polyolefin, and a slip agent, e.g., amide. A method of shielding a pile from downward force exerted by backfilled earthen materials during settlement includes the steps of providing a friction reducing jacket constructed of sheet material comprising a thermoplastic polymer and an amide slip agent; driving the pile into soil, leaving a portion of the pile above the soil exposed; wrapping the friction reducing jacket around the exterior surface of the exposed portion of the pile such that the interior surface of the jacket contacts the exposed exterior surface of the pile; and placing backfilled earthen materials around the jacketed section of the pile.

A pre-stressed pultruded glass fiber reinforced thermoplastic lumber suitable for demanding construction environments, particularly marine and outdoor applications, features a solid core composed of a thermoplastic, such as PVC, blended with 15% to 40% by weight of pelletized chopped strand glass fibers. Pre-tensioned elongated continuous fiber reinforcements are embedded within and coextensive with this core via pultrusion. The presence of pelletized and fragmented glass fibers within the core enhances the mechanical coupling between the core and the continuous reinforcements, facilitating the transfer of tensile stress to the core as compressive pre-stress. An outer co-extruded cap stock provides protection against UV and IR radiation and enhances impact resistance. The resulting lumber exhibits a high modulus of elasticity (exceeding 800,000 psi), at least 60% fiber length retention, improved durability, and resistance to common wood degradation factors without the use of toxic chemicals.

A pile is comprised of a pipe, i.e., a hollow tube or hollow cylinder, with a coextensive internal reinforcement comprised of a plurality of intersecting walls. The pile is comprised of a blend of a thermoplastic and 20 to 50% (pbw) pelletized chopped strand glass fibers. The outer surface includes a co-extruded cap stock that is relatively smooth and exhibits a relatively low coefficient of friction. Internal walls define a central channel useful for water jetting, and peripheral channels useful for electrical, plumbing and mechanical lines. The internal structures exhibit roughness, bumpiness and a relatively high coefficient of friction for an extruded plastic. A groove may be formed in the pile adjacent to an end for resistance to uplift.

An integrally formed, pre-stressed thermoplastic lumber product and a method for its manufacture are disclosed. The product comprises a core of a thermoplastic polymer, such as PVC, blended with chopped strand fibers. A plurality of pre-tensioned continuous fiber reinforcements are pultruded axially within the core. Enhanced frictional and mechanical coupling between the chopped fibers and the continuous reinforcements resists delamination and enables the effective transfer of tensile stress into compressive pre-stress within the core. The resulting lumber, finished with a co-extruded capstock layer, is a high-stiffness composite exhibiting a modulus of elasticity of at least 650,000 psi. The method involves the simultaneous co-extrusion of the core and capstock around the tensioned, pultruded continuous reinforcements.