The Speciality Tests Of Freeze-thaw On Deep Soil And Research On Project Application

Exploring artificial freezing soil's speciality of frost-heaving and thaw-settlement is key-technology and important basal research about popularing artificial freezing method for municipal underground space. Owing to being lack of uniform frost-heaving tester at present in China, in the paper, the author has developed the frost-heaving device which introduces computer to gather data. For the first time,Aiming at representative soil group--clay. By the device, it uses single ingredientand orthogonal experimentation to proceed the frost-heaving ratio and frost-heaving stress test systematically.After the opening frost-heaving ratio test, the paper studies the soil's frost-heaving's relationship with the freezing end temperature, water content, dry-density and upside load, the frost-heaving ratio minishs linearly with the freeezing end temperature augment ,water content reducing and dry density reducing; the frost-heaving ratio augment with power exponential rule to upside load's augment. There is four factors influence the frost-heaving ratio: water content prominence, freezing end temperature at second place.After the opening frost-heaving stress test, the paper studies the soil's frost-heaving's relationship with the freezing end temperature, water content, dry-density and upside load, the frost-heaving stress minishs with the freeezing end temperature augment, water content reducing , dry density reducing and upside load reducing.After frosting-thawing tests, I gain some change rules on structure characters such as the density, hole ratio, compressibility, intensity, pervasion quotiety and so on in former and after freeze up. Overpass analyse the test data of temperature and displacement, I know the position of ice in freezing process, the develop rulus of temperature field in the process of frosting-thawing and the develop rules of frost-heaving quantity and frost-thawing quantity in freezing and thawing process.Besides, after frost-heaving tests, we gain some change rules on physical characters such as the transformation rule of moisture, dry density in former and after freeze up. Pass the test data of frost-heaving ratio and frost-heaving stress, using regress the relationship curves, analyse educe the connection formula of frost-heaving ratio and frost-heaving stress.Finally, it discusses the application of the research production in engineering and brings forward some designs and technical steps about controlling frost-heaving in freezing projects. These task has great applied importance and guide significance to the artificial freezing method's practice in the engineering and will reduce the endangerment to the ambience in the future.