In two recent studies by Miaou, he proposed a method to estimate vehicle roadside encroachment rates using accident-based models. He further illustrated the use of such method to estimate roadside encroachment rates for rural two- lane undivided roads using data from the Seven States Cross-Section Data Base of Federal Highway Administration (FHWA). The results of his study indicated that the proposed method could be a viable approach to estimating roadside encroachment rates without actually collecting the encroachment data in the field, which can be expensive and technically difficult. This study tested the consistency of Miaou’s approach using two data sets from FHWA’s Highway Safety Information System (HSIS). In addition, by synthesising the models developed from this and previous studies, a roadside encroachment rate estimation model was recommended. The model allows the rates to be estimated by average annual daily traffic volume, lane width, horizontal curvature, and vertical grade for rural two- lane undivided roads. (A)
Samenvatting