Research The Freeze-thaw Characteristics Of Dead-weight And Collapsible Loess T In Longdong

In this paper, the large thickness collapsible loess for the study in Longdong area. Select typical venue that the field station constructed and pipeline laid more intensive. By large submerging in-situ test, in-situ freezing and thaw test, As well as the indoor experiment freezing temperatures and freezing water content affect collapsible loess, Research the study freeze-thaw environment impact the collapsible loess. Made some new results and knowledge.First, based on the regional environmental analysis of geological conditions, Dig exploratory wells sampled for soil test (spectrum analysis, particle size analysis, consolidation test, etc.), comprehensive understanding loess in Longdong from the material composition, physical properties, and other aspects of collapsibility. Preliminary evaluated loess collapsible type and site grading.Laid a large test pit in-situ test, inbuilt subsidence observation punctuation in slightly larger depth than the range of collapsible buried deep, Site monitoring for three months of submerging test data, combined soil samples indoor collapsible test data, Analysis quantity of flooding during the test, collapsible ground subsidence process, deep soil collapsible settlement process, Water transport processes and diffusion range, the development law of wetting angle and fracture, the scope of founder affect. Get the type and grade of area collapsibility, collapsible limit the depth and area correction coefficient β0.By frost expend thaw sink test in-site, Near freezing begins water injection, and the surface soil freeze in saturation, melting next year get warm again after a cold spell, Get the amount of frost heave and thaw settlement saturation soil in superficial part, Reveals the depth and extent of the influence that temperature influence on soil temperature, Studied the law of loess frost heaving and thaw subsidence. Loess freeze-thaw tests conducted indoors, with humidifying, dehumidification make up different water content samples of loess, test loess about thaw deformation, compression deformation collapsible deformation affected by temperature in the absence of water conditions, The main research on saturation loess character frost heave and thaw under condition freezing thawing, Recognizing whether the loess is frost heave depends on the water content of frost is over "critical heaving water content. Analysis the impact of collapsible loess of freezing and thawing.Analysis transformation law of the collapsibility loess with different humidity and pressure. The results show that the generation of collapsible loess caused is "rigid" node degeneration of loess hole overhead. Collapsible rate beyond increases by moisture content added with the same level of pressure; the initial water content at the same level, with increasing pressure beyond collapsible rate becomes larger. In this paper, get the rate of collapsible loess beyond concepts and influence of external factors.