The objective of the finite element model is to predict the response of a 10 inch deep sheet pile, with voids on the web and the flange wall section, to various pressures representing design loadings. To verify the preliminary design of the 10 inch deep voided z section the following steps should be taken: (1) Comparing linear FEA model stresses with those obtained from the stress equal to the moment of inertia divided by the section modulus. Also, the overall section properties will be used to insure that the voids are not causing large stress concentrations which were not predicted by the stress equation. (2) Comparing the FEA predicted maximum deflections with the SPW 911 (PileBuck) software predictions, thereby comparinghome depot chain link estimator a method which incorporates material properties and detailed surface geometry (FEA) to a method which only uses the overall section moment of inertia to classify the sections geometric capacity Verifying that the 10 inch deep section behaves linearly elastic under the service conditions given in the design tables in Chapter Buckling Analysis The objective of this chapter is to use finite element analysis and analytical expressions to predict the buckling modes and critical buckling loads of single and double WPC z-sections under various end restraint conditions.

Flexural Testing The objective is to determine the material properties of a double vinyl z section and provide baseline flexural data for comparison with future tests of voided WPC sections. Also the design and development of lateral bracing and a support system for ultimate strength flexural testing of PVC and WPC double z-sections. Summary WPC has potential for waterfront applications such as retaining walls. The material properties and behaviors have many advantages over traditional materials, such as cost and durability. The conclusions from the design of a WPC voided z section are given in Chapter 6. 5 Chapter : Preliminary Section Design Introduction The preliminary design of a retaining wall section is presented in this chapter. The design consists of a wood plastic composite (WPC) material having a hollow zsection sheet pile geometry The purpose is to evaluate the geometric composite outside house steps efficiencies of hollow sheet pile design verses a ribbed flange design; and material efficiencies of WPC compared to the polyvinyl chloride (PVC) sheet pile section currently available on the market as manufactured by Crane Materials International . Initial design was accomplished using the following steps: The potential hollow shapes and distribution patterns were evaluated. Minimum wall thicknesses were selected. Minimum wall thickness is dictated by extrusion limitations, as are maximum overall section dimensions

Nine preliminary section geometries were developed based on considerations Geometric efficiencies of the new sections were evaluated and compared with efficiencies of existing ribbed flange geometries. These efficiencies were evaluated under three conditions: hollows present in the web only, hollows present in the flange only and hollows present in the flange and web. Materialbest wood fencing material efficiencies were evaluated for two options of sheet-pile material composition; wood plastic composite sections and polyvinyl chloride Preliminary design tables for common hollow z-section sizes were develop These tables provide the maximum wall height for a number of backfill conditions and loadings. Hollow WPC sheet pile sections are recommended for further laboratory work, and final section design is accomplished using FEA modeling . Objective The objective of this chapter is to present the preliminary design of a hollow zsection WPC sheet pile profile, which is efficient in terms of cross-section geometry and material utilization. The proposed WPC profile is compared with a ribbed z-section PVC sheet pile profile with similar cross-section dimensions, which is currently on the market. Background WPC Background Wood plastic composites (WPC) consist of a wood filler within a thermoplastic polymer.