District Statistical Analysis Of Bearing Capacity Of The Q₃Loess-like Silt In Shanxi Province

Roads as a banded structures often need to across many loess areas that have different geologic ages, geological formation causes and geomorphic units.However, deep research and statistical basis in the design of highway subgrade are lack. Therefore, to ditermine the foundation bearing capacity of the loess is a key technology for soloving the stability of the subgrade in loess area highway design and construction.Malan loess (Q3)of Shanxi Province possesses certain collapsibility which may form adverse effect on the bearing capacity of loess ground. Combining with the characteristics of highway engineering, the further study on the loess distribution in Shanxi Province on the summary of collapsible loess characteristics. Combining with the regional factors such as climate, soil properties and so on, region IV in Shanxi Province is divided into â…£1a and â…£1on the base of collapsible loess engineering geological zoning in China. Through collecting the site loading test data lab soil test data of Q3loess-like-site, the statistical formula of bearing capacity for Q3loess-likes silt are provided. In these formulas, multi-factors are considered, such as natural content and the ratio of the liquid limit to void ratio or the saturation and the ratio of the liquid limit to void ratio. This is the first time to take saturation as bearing capacity statistical variable. Based on statistical correlation coefficient of each formula about bearing capacity formula in Shanxi area, optimum formula of Q3loess-like-silt bearing capacity is proposed,which can be refered for design of highway engineering.The statistical formalas are examed by engineering projects located in divisions of â…¢,â…£1a and â…£1b,respectively. The calculated bearing capacities by using the optimum formula proposed in this paper agree well with those determined by loading tests in-situ. The relative errors between the load test value and the predicted value are less than10%. The statistical formulas are applicable to engineering practice in Shanxi area.