The Loess Region Bump To Deal With New Methods Of Research

Though much more freeways are constructed in China in recent years, Vehicle Bump Approaching Bridge(VBAB), being a universal problem of engineering, still can't be solved effectively. VBAB maybe occur owing to non-uniform deformations of bridgehead and road on both sub grade of soft clay and foundation of collapsible loess, which is caused by textural difference and etc.Non-sand Concrete Mini-pile (NCM) is favored by engineers because of its advanced technology, simple equipment, handy working, low cost, unpolluted surroundings and so on. After several years of engineering experiments and practices, NCM shows its glorious future in foundation treatment. Post Treatment Method (PTM) has engineering advantages of Sandy-well Ground and Preloading Method, which can validly reduce post settlement of high-filled sub grade when being used. Foundation deformation will decrease evidently if VBAB problem is processed by NCM, which reconsolidates sub grade, increases sub base deformation modulus and compacts the soil. Ideal elastopllastic theory is put up to calculate the deformation of soil stabilization on account of detailed characters in treating road sub grade, and Layer wise Summation Method (LSM) is used to compute sub layer settlement.Multiline Test Method of loess sample is brought up under the base of studying structural feature, collapse character, deformation mechanism and others of collapsible loess. Loessial pre-deformation will be gained through loess sample's stress-strain relation in different dampness. Additional stress will be considered under the condition that the deformation of saturated loess is equal to that of pre-humid loess, and as a loessial imposed load, it will be used in engineering design. Non-uniform settlement caused by collapsible distortion of loess will be fully avoided, and VBAB will be alleviated or slaked.Deformation computation of composite sub grade is a complicated systematic engineering, and PTM, which has distinct advantages in comparison with other methods in consolidating high-filled sub grade, is a new idea in treating composite foundation. Design idea that PTM treating sub grade of collapsible loess is merely put up in this article, and further study should be carried in collapse probability of local loess and deploying of PTM.