Under the background of "double carbon" strategy and "park city" construction, urban outdoor furniture not only carries functional use needs, but also becomes an important carrier of sustainable concept. In view of the lack of cultural expression of traditional wood-plastic composites, this paper proposes the strategy of filling high-density polyethylene/wood fiber composite system with clay, aiming to improve its physical properties and endow it with regional cultural imagery. Through systematic experiments, this study evaluates the effects of different clay content on the mechanical properties, shrinkage, friction coefficient and combustion characteristics of materials, and combines with semantic difference evaluation to explore the effect of material texture on user perception. The results show that the material with 5 wt% clay content has the best performance, the tensile yield stress is increased by 26.5%, the ignition time is delayed by 5s, and it is better than other materials in the dimension of "place awareness". However, when the clay content exceeded 7 wt%, the performance decreased. The study proposes a new way to pay equal attention to material performance optimization and cultural expression. It is concluded that terracotta enhanced WPC not only has advantages in structural performance, but also shows the unique potential of cultural embedding in sustainable design, expanding the humanistic connotation and expression of green product design.