Study On Material Properties Of Weathered Granite Stabilized With Cement In Coastal Region

While East Shandong coastal region is located in mountainous, rock stratum burying shallowly, and embankment and foundation with good support conditions. Besides, traffic volume was small, and there was almost no heavy traffic. However, during the operation process of road in this region, the material properties decayed rapidly, and the early pavement disease was serious. Weathered granite material distributed widely in this region, and it was a special type of soil, the particle of which had low strength, and turned soft approaching to water easily. But cement stabilized weathered granite material was always used as semi-rigid sub-base material, so the material properties of it directly affected the quality of road construction and level of service in this region. Besides, due to the special climate and terrain conditions in this region, pavement materials stood long-term effects of soluble salts, which may lead to quick decay of weathered granite material properties. Hence, it is important to study the initial material properties of weathered granite stabilized with cement and decay status of the material properties under soluble salts influence for optimizing material design and easing early pavement disease in this region.Combined with application status of in sub-base, based on stratigraphic distribution and engineering properties of weathered granite material, carried out engineering characteristics zoning of weathered granite material in the region. Then, adopting corrosion with soluble salts solution, studied on the material properties, including unconfined compression strength, cleavage strength, compression rebound modulus, frost resistance property, erosion resistance property and shrinkage resistance property, etc., of cement stabilized weathered granite materials with3coarse content:20%,30%and40%, under standard, soaking and leaching solution curing conditions. Through comparing material properties under different curing conditions, evaluated coarse aggregate content effect to the initial material properties and soluble salts corrosion resistance property of cement stabilized weathered granite material.Adopting finite element calculation, analysed pavement structure mechanical response,whose subbase was cement stabilized weathered granite material with different content of coarse aggregate.The results showed that, through studying on stratigraphic distribution and engineering properties of weathered granite material, the regions can be divided into two engineering characteristics zones:Proterozoic and Mesozoic partition; with coarse content increasing, except that cleavage strength decreased slowly,the initial material properties of cement stabilized weathered granite material showed a rising trend, and the increase was less when the content increased from30%to40%; the content being20%, the material properties was poor under long-term soluble salts corrosion condition:corrosion resistance coefficient of properties were below0.3mostly, compression rebound modulus was only0.067, and erosion resistance property was almost lost completely; under soluble salts corrosion condition, with coarse content increasing, material properties improved gradually, when the content increased to40%, under long-term soluble salts corrosion condition, except of erosion resistance property, material properties could reach more than60%of those under soaking curing condition; under the condition of soluble salt corrosion, high stress location raised to base from subbase, resulting in the deterioration of base bending condition, but with coarse aggregate content of subbase increasing, bottom tensile stress of base reduced gradually, when coarse aggregate content increased to40%, base bending condition turned ideal. In general, subbase should adopt cement stabilized weathered granite material including40%coarse aggregate in the area influenced by soluble seriously, while in the area influenced by soluble mildly, subbase should adopt cement stabilized weathered granite material including30%coarse aggregate to control layers modulus ratio reasonably.