Case Studies: Hybrid Sheet Piling – Fiberglass Rein-forced PVC Profiles

This case study shows how we introduced to the market new hybrid material to manufacture sheet piling that would bridge the gap between vinyl polychloride and steel. We present here how we conducted the research, developed the manufacturing line, followed by lab and field tests to ultimately introduce the patented product to the market.

Case-fiberglassABridging the Gap
Sheet piling made of polyvinyl chloride is a long-lasting prod-uct of high resistance to corrosion, as well as the majority of chemical agents. In contrast to steel piling, profiles made of PVC are lightweight, which allows to make savings, as far as the transport and assembly costs are concerned. Aesthetic look is an additional advantage of PVC. On the other hand, the largest limitation of this type of sheet piling is their consid-erably lower resistance to bending, which limits the scope of application, especially in case of projects where long ele-ments are used.
The above limitations made us conduct a comprehensive research aimed at improving the mechanical parameters of vinyl sheet piling and, at the same time, maintaining all advantages of PVC profiles. The Pietrucha Group R&D department has developed a technology of reinforcing PVC sheet piling with fiberglass in form of roving.

Step One – the Research
The initial stage of the research assumed the development of surface, layered model of a profile, with five variations as far as the fiberglass location was concerned. The fiberglass content did not exceed 10 percent of the total mass of the composite. In the next phase, the team conducted finite elements analysis. The results of the analysis helped to select the optimal location of fiberglass core, i.e. reinforcement of horizontal walls and corners of the profile. The next stages of the research included analysis of different reinforcement mass share. In addition, the team analysed further variations of the initial reinforcement location and validated the results of the finite element analysis with the numerical analysis of the 3D spatial model.

Step Two – the Tool
The research results helped to determine the optimal geometric and quantitative location of fiberglass reinforcement within the polymer matrix, so as to achieve the highest mechanical parameters of the profile. Then, the team moved on to design and assemble the extrusion tool for fiberglass reinforced GW700. The available technologies of PVC reinforcement used for small profiles, such as window frames etc. were reviewed. In a consortium with the World’s pioneer in fiberglass technology, we have adapted this solution to strengthen large scale profiles. A complete manu-facturing line was assembled, equipped with tools that would enable coextrusion of profiles with fiberglass reinforce-ment

Step Three – Lab Tests
Then, the manufactured hybrid geotechnical profiles were tested at the Silesian Science and Technology Centre of Aviation Industry. The Silesian Centre specializes in testing the strength parameters of advanced geo-composites used in the aviation industry, inter alia, by Boeing. The static and fatigue analysis included 4-point bending of the profile using a specially designed testing unit. During the experiment the force and the material shift were monitored on a continuous basis. Thanks to the obtained results the Young Modulus and the flexural rigidity parameters of the product were calculated.

Step Four – Field Tests
Moreover, the results of bending tests have confirmed the improvement of the new hybrid material mechanical prop-erties. The samples’ stiffness parameter of the fiberglass reinforced vinyl sheet piling nearly doubled in comparison with sheet piling made solely of PVC. In order to confirm the results, and the ability of the hybrid material to bear constant tension, field tests were conducted. The tests were run in real-life conditions. The walls made of hybrid material were submerged in the ground and subjected to bending. The results of the field tests were repetitive and confirmed the lab assumptions.

Step Five – the New, Patented Product
Application of the innovative technology resulted in the creation of hybrid sheet piling made of fiberglass reinforced polyvinyl chloride. Thanks to comparable mechanical parameters, the new type of material occurs to be a strong competition to light steel piling. Furthermore, aesthetic look, resistance to corrosion and lower price are some of the additional advantages which make our product more attractive.

Further Information
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Categories: Case Studies