Optimum Size Solution for Roadside Structures Based on FAHP Evaluation

Roadside landscape can be for a restorative function on ecology or for appreciation, but it may also bring clutter and traffic accidents. A literature review has identified that a lack of size regulation on roadside structures is the direct reason for this phenomenon. This paper aimed to investigate the optimum size solution. A Fuzzy Analytic Hierarchy Process method was used to evaluate the multi-criteria decision making problem. Evaluation indices focused on harmony with the environment, conspicuity, excitement, or depression degrees to viewers. Ten roadside structures in varied sizes formed the evaluation alternatives set. Experts gave their perceptual judgments on the alternative sets. The results revealed that roadside structures that are 25 m3–49 m3 have an excellent visual quality in the evaluation process and were considered to be the optimum size for roadside structures. The results could provide a theoretical basis for flexible landscape design in transportation corridors in China.