Engineering Properties Of Compacted Loess And Its Application Problem

Loess, a kind of special soil which was widely spread in Northern China, has been abroad used in road construction.. In recent years, with the rapid development of road construction, study on engineering properties of unsaturated and compacted loess has been more and more significant.Based on field investigation for diseases of Xibao Highway, the paper analyzed distribution laws, types and occurring mechanisms of highway diseases, and proposed that engineering properties of loess is one of the important reasons of the road diseases. Therefore, focused on the unsaturated loess, by means of compression, direct shear and triaxial compression tests, the paper studied the characteristics of deformation and strength of the unsaturated and compacted loess, and analyzed the influence of water content and dry density of samples on their deformation and strength, and further proposed the calculation formula of road bed subsidence. Some primary results are acquired as follows:The roadbase and pavement diseases of highway influence and strengthen each other. Over-subsidence of road bed is one of the important reasons causing the roadbase and pavement diseases. The roadbase subsidence was divided into unitary subsidence and partial subsidence. Based on the order and extent of function of water and loads, the partial subsidence was divided into 3 types: water overwhelming, loads overwhelming and water and loads having coupling function.Under the direct foundering condition, the total deformation of compacted loess of same dry density is related with original water content and pressure, and is no long the single function of pressure. The total deformation of saturated compacted loess is the single function of pressure, and the function between its total coefficient of deformation and pressure can be used for calculation of maximum subsidence of road bed combined with the improved layer settlement accumulation method.Under the same dry density condition, coefficient of compressive deformation increases with increscent vertical pressure. Under the same vertical pressure, coefficient of compressive deformation decreases with increscent dry density. Under the same pressure, coefficient of compressive deformation increases with increscent original water content of samples, the function between coefficient of compressive deformation and pressure can be used for...