Study on Factors for Determination of Highway Subgrade Height

With increasing concentration on highway land issue as the new round of highway construction, reducing land occupation and earthwork volume of highway engineering is necessary under the historical background of building “resource-saving and environment-friendly” society. It’s been widely known now in the industry that subgrade height of highway in China, especially high-grade highways, is on the high side. Therefore, it’s significantly necessary to discuss and study on appropriate subgrade height. This paper explains advantages and disadvantages of low-filled embankment and expounds current situation of indexes for subgrade performance – moisture, modulus resilience and permanent deformation; it proposes basic thinking of determining subgrade height mainly through meeting subgrade performance and engineering requirements and realization approach of the method.