Citation :

Albert Jorddy Valenzuela Inga, Nelfa Estrella Ayuque Almidon, Gianswen Kevin Meza Terbullino, Jesús Eugenio Depaz Huertas, Janet Yéssica Andía Arias, "Proof of Concept and Stress Analysis of an Improved Telescopic Strut for Slab Formwork: Design and 3D Modeling," International Journal of Civil Engineering, vol. 13, no. 6, pp. 231-240, 2026. Crossref, https://doi.org/10.14445/23488352/IJCE-V13I6P116

Abstract

Shoring systems and formwork are necessary in reinforced concrete construction to allow stability during the pouring and setting of the construction. Conventional metal telescopic props, controlled by EN 1065, use a pin-and-hole adjusting system, providing structural constraints that inhibit longevity and enhance the probability of deformation under heavy usage. The present study hypothesizes and analyzes, using the Finite Element Analysis (FEA) in Autodesk Inventor, a better threaded fitting system that will substitute the traditional pin with an Acme threaded mechanism and crank, and create no holes in the tube. ASTM A36 steel in two different configurations was modeled and compared: the traditional model with a pin (BL) and the suggested model with a threaded mechanism (PR) under three loading conditions. The results indicated that the BL model exhibits severe stress levels in the perforated areas, which are characterized by stress of 6895 MPa, displacement of 196 mm, and a safety factor of 0.12 under combined loading. Conversely, the PR model revealed values of 442 MPa, displacements of 16.57 mm, and a factor of safety of 0.56, which are 90 percent less than the deformations. The threaded mechanism redesign removes stress concentrations and enhances load transmission and augmentation of the assembly stiffness without altering the commercial size of the strut. The results confirm that the threaded system is the best to incorporate in the structure to enhance its performance with respect to safety and longevity when used on the ground.

Keywords

Autodesk inventor, Finite Element Analysis, Design, Steel prop, Structural optimization.

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