Page 45 - eBook_Proceedings of the International Conference on Digital Manufacturing V1

Mechanical Performance and Structural Feasibility of Recycled HDPE in
Furniture Design: Experimental and Finite Element Analysis

FEA simulations incorporated these experimentally derived
material properties to evaluate the structural response of a seat
prototype under static loading conditions of 68.4 kg (an average
adult weight) and 100 kg (upper threshold). The seat geometry
was discretised using a tetrahedral mesh with mesh refinement in
high-stress regions. A bonded contact was assumed between the
seat surface and supporting frame.

Simulation results showed that the maximum von Mises stress
remained below 10 MPa for both loading conditions—well within
the experimentally determined strength limit. Displacement
values peaked at 4.1 mm, primarily concentrated in the mid-span
region of the seat base. The safety factor exceeded 2 in all cases,
suggesting a conservative design margin. Notably, the FEA
highlighted load-bearing regions and indicated that reinforcing
ribs could further enhance stiffness.

While the structural performance is promising, inherent
variability in recycled HDPE due to possible differences in
polymer grade, thermal history, and flake morphology must be
acknowledged. Future studies should consider long-term effects
such as creep and fatigue, particularly under cyclic loads common
in furniture applications. Additionally, incorporating failure mode
analysis (e.g., buckling or cracking) would provide a more robust
structural evaluation.

Finite Element Analysis (FEA) Result

Finite element analysis was meticulously conducted to evaluate
the mechanical integrity of the designed ergonomic stool under
realistic and extreme loading conditions. Two critical load
scenarios, representing an average adult human weight of 68.4 kg
and an increased load of 100 kg, were considered to reflect the
robustness of the structural design comprehensively. The results
for stress distribution and displacement under these loading
conditions are presented in Table 6.

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