Page 43 - 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

Load Application and Boundary Condition

The finite element simulation applied a uniformly distributed
vertical load equivalent to a human body mass of 68.4 kg
(approximately 671.004 N) across a defined seat surface area of
1512 mm², resulting in a consistent pressure of 0.4438 N/mm².
This loading condition closely mimicked real-world ergonomic
seating scenarios. Fixed constraints were applied to the base
supports, replicating stable contact conditions with a rigid floor.

Computational Result and Interpretation

FEA results provided critical insights into the stress distribution
and displacement behaviour of the stool under load as
summarised in Table 5. Maximum von Mises stress was observed
at the interface regions between the HDPE seat and steel support
frame, with peak stress levels reaching 3.682 MPa. These
concentrated stress regions were anticipated due to stiffness
mismatch between the relatively compliant polymer surface and
the more rigid metallic framework.

The observed maximum displacement was 1.243 mm,
predominantly occurring at the centre of the seating area,
reflecting acceptable structural deflection underload. Stress values
at distant regions were negligible (approximately 9.404×10⁻³
MPa), indicating efficient stress distribution throughout the
structural framework.

Table 5: Result of Analysis

Load (68.4 Minimum Maximum
kg)
Stress 0.4438 Pa 9.404 x 10 MPa 3.682 MPa
-6
Displacement 1.243 x 10
-2
0.4438 Pa 0 mm
mm

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