| China is importing oil from Russia to ensure energy supplies. The oil transportation pipe engineering, Mohe to Daqing, is covering about 500 kilometers permafrost areas and 465 kilometers seasonal frozen soils areas through Da Hinggan Ling,Xiao Hinggan Ling in northeast and the north of Nenjiang plain. The frozen soil in this area is subsidizing gradually, and the geological condition is complex, while badness of frozen soil growing, characters of frozen soil-along the line are greatly different, so it is possible to result in serious harm for security of pipe engineering. As particularities the design and construction of pipe for oil transportation in frozen soil areas have, the temperature of oil transported impacting water-heat state of frozen or melt soil all around and along the line, even impacting physical mechanics specialities of frozen or melt soil, it would have been threatening stability of whole and integrality of structure. Therefore, it is a significance to carry on research on the engineering characters of frozen soil along the line and all geological problems related to.In order to meet the demands for evaluation of survey and design of construction at the beginning of the pipe engineering, frozen soil lab of Jilin University accept the commission from Daqing Oil Engineering limited Company to take large numbers of frozen soil special experiments on indices for frozen soils according to various requirements referred by permafrost technical requirements for engineering geological investigation ofChina-Russia Oil Pipeline.The text tests physical indices of groundsill soils got along the line with various experiment measures first. It includes unfrozen water content, aggregate specific heat, volumetric specific heat, coefficient of thermal conductivity, and thermal diffusivity. These physical parameters are all important indices for heat-matter quality research on frozen soil and design of construction. In this content, it stresses the testing research on unfrozen water in frozen soil, and analyses unfrozen water content measurement of initial freezing temperature and unfrozen water content measurement on testing unfrozen water content in frozen soil in theory, indicating that there is a problem confusing the concept of temperature existed in unfrozen water content measurement of initial freezing temperature. The unfrozen water content measurement of initial freezing temperature come out from the forecast mode of Wu=αθ-b, actually, it makes unfrozen water content at the initial freezing temperature be that in random minus temperatures. Comparing the simulation test data, the results of unfrozen water content measurement of initial freezing temperature experiment are uncertain. Contrarily, unfrozen water content measurement of heat can carry on the experiment according to conversation of energy theory and deduce the calculation formula, the test principle being legible, it is substantiated by a great lot of experiments that the precision of unfrozen water content measurement of heat is higher, and well met with the use requirement for construction design.The text also makes the general experiment research on six kinds of original soils in this area by taking unfrozen water content measurement of heat, and makes a conclusion of the effect law of unfrozen water with temperature, soil, and liquid water content. The temperature is the most important factor to effect on unfrozen water content. With temperature falling and unfrozen water content decreasing following, the ranges which unfrozen water contents in different soils change violently in are different. The relationships to temperature and average unfrozen water content in each temperature with six kinds of soils reflect that, as decentralization of soils growing (plasticity growing), the unfrozen water content increases. In the same minus temperature, unfrozen water content in organic soils is higher than that in non-organic soils, and the more organic matter in organic soil is. the more unfrozen water content is. The influence of beginning liquid water content on unfrozen water content in organic matter soli is greatly obvious. The degree in turn that beginning liquid water content effects on unfrozen water content is clay, silty soil, clayey silt and gravelly sand.The text summarizes representative unfrozen water content value (average value) in certain minus temperature in each kind of soil along the oil pipe engineering and numerical value of parameter a, b in currency formula, the power function wu=at-b, of unfrozen water in frozen soil by analyzing the effect factor on unfrozen water. On this basis, it concludes the experience calculate formula of wu-wp-t of clay, clayey silt, silty soil, peat soil and simple regression equation with two unknown of relationship with wu-wo-wp in certain temperature. These experience formulas reflect not only the general law of unfrozen water that soil, liquid water content and temperature effect on, but also offer references to fix on unfrozen water content for engineering.The basic physical parameters of frozen soil that the text finishes include coefficient of thermal conductivity, volumetric specific heat, thermal diffusivity and aggregate specific heat. These parameters are application indices of frozen soil thermodynamics, and it is hard to get directly at site, mostly in lab. The ways we get parameters are. heat-flow meter in steady-state technique to test coefficient of thermal conductivity, normal state techniques to test thermal diffusivity. unfrozen water content measurement of heat to test aggregate specific heat and volumetric specific heat.While testing aggregate of several kinds of soils, such as turf, peat soil. clay, clayey silt, silty soil and various gravelly sands in frozen area in Da Hinggan Ling, analyzing and comparing, we get to know that aggregate specific heat of frozen soil is minishing, as granule turning thick and plasticity weakening. It is concerned not only with the size of granule and plasticity, but also with the content of organic matter in soil. The more content of organic matter is. the bigger value of aggregate specific heat is. According to results of volumetric specific heat experiments under the condition of-10 degree, it is discussed by classification of soil with the relation to the chief liquid water content and dry bulk density. It is found that volumetric specific heat of frozen soil is always growing with the chief liquid water content and dry bulk density increasing, and the linearity relativities are all fine, while analyzing Cvf_W_γd test data of four kinds by simple linearity regression equation with two unknown. Combining unfrozen water content with aggregate specific heat, the chief liquid water content and dry bulk density also being in connection with, it can figure out the volumetric specific heat of frozen soil at any minus temperature. The heat-flow meter is used to test coefficient of thermal conductivity of frozen soil. It comes out theλ_ω_γd linearity regression equation of five typical soil in Da Hinggan Ling, and the linearity relativities are better. It is well proved to use the heat-flow meter that the law and influence on coefficient of thermal conductivity that state of frozen or melt, liquid water content, dry bulk density and soil condition affect.There are many countries in the northern hemisphere locked into the problem of frost heave and thawing settlement, and it is very deficient to study the special science and technique of frozen soil, especially geotechnical engineering and piping engineering in cold areas. The second part of the text is to analyze frost heaving susceptibility of different soils and thawing settlement in piping areas by experiments indoors.Carrying on the frost heaving simulation experiment on typical soils indoors and finding out the connection between frost heaving ratio and each factor, soil condition, liquid water content, saturation, green density and so on, it analyzes the chief factors respectively that affect on the frost heaving susceptibility of fine-grain soil and coarse grained soil. For the frost heaving of fine-grain soil, the higher initial frost heaving water content needed is, the weaker frost heaving is, while plasticity index is greater in the same liquid water content. Because the law of frost heaving of clay and silty soil is almost the same to the changing of over-plasticity water content(W-Wp), it can be classified by the relationη～(W-Wp) which fine-grain soils classification of the frost heaving susceptibility is according to. As the frost heaving of fine-grain soils being affected by saturation and green density, it is falling while the green density is growing at the same saturation, and growing while the green density or saturation is growing at the same liquid water content. While analyzing the regression equation ofη～(W-Wp)-Kd/Sr, the contribution of (W-Wp) to the frost heaving of soil is bigger than that of Kd or Sr. It is showed that the over-plasticity water content is the chief factor that affects the frost heaving value of fine-grain soil.With the research on the classification and frost heaving susceptibility of coarse grained soil, we can get to know that the liquid water content in soil is the most important factor to make it frost heaviy, and the effect of the mud content is limited. The frost heavy ratio is growing while the water content of it is growing from silt sand to coarse sand. It can be concluded by comparing to the criterion that the limited value of criterion is ill-suited, and the soil whose mud content is below the limited value is still to frost heave at some liquid water content, some even heavily. Criterion of the frost heave of coarse grained soil except silt sand has a lot of problems obviously on insecurity in the regulating the limited value of soil classification, mud content, and connection between freezing ratio and liquid water content, and it is worth being discussed.In the analyse on range which cause the frost heaving anamorphic of the pipe between 2 to 6 meters of groundsill frost heaving, it is shown that the frost heaving of clayey silt in the range between 2 to 6 meters along the AB sect is the main reason to cause the damage of the pipe in this sect. According to the experiment data, the frost heaving of clayey silt along the line is no obvious regulation. It is possibly caused by water supplying condition of each sect. There are coarse grained soils in the AB sect, the most are sands, thick pellet soils and breccias, and sands are belong to the weak frost heaving, which lies on the water content, considering the change of water condition probably caused after pipe operation. For some lower inartificial water content in weak frost heaving area, it is needed to consider the probability of turning frost heaving or harder if water enough. The thick pellet soils and breccias contained in this sect can be dealt with non-frost heaving.The text finished 345 in six kinds soils thawing settlement experiments, including pebble, sand, silty soil, clay soil, peat clay soil and peat soil. It indicates the experience measurement of thawing settlement coefficient and thawing compressing coefficient for perennial-frost soil, and research further on classifying the thawing settlement of frozen soil by large numbers of experiments.It summarized the connection of thawing settlement coefficient a0 for each kind of soil with the liquid water content and dry density, and each of thawing settlement susceptivity is different. That of silty soil is the biggest, and gravel, while the condition having, can be caused a considerable settlement, but thawing settlement is smaller as a whole, commonly a fine frozen groundsill. There is two kinds of soils added, peat clay soil and peat soil, comparing to the criterion in research on the classification of frozen soil thawing settlement. It indicates the limited water content and limited over-water content in each thawing settlement grade on the basis of regression analyse. It is not a constant within the load range (200 KPa) in experiment of the thawing compressing coefficient, but minishing while the load growing. So it should not be a fixed value for the volumetric compressing coefficient mv after frozen soil thaw, moreover, it should be the value according to the practical pressure. The mr-γd regression connection and digital diagram of the six kinds of soils summarized can be used in practical engineering.Frozen soil is a kind of soil impressible to the temperature, and the physical mechanics of it was to change while the temperature is changing. It is a necessity to destroy the heat balance founded between frozen soil and atmosphere by laying the oil transportation pipe in perennial-frost area, and make the big change for temperature of groundsill and process of freezing and thawing, thereby, cause the blight for basal stability of pipe. In allusion to the character of construction and running of pipe engineering, it is most meaningful to make the forecast for groundsill of pipe within the service life of temperature field.The text sets up a ideal physical model for soil temperature field around the pipe, and indicates a certain assuming condition, according to the limit condition offered in literatures and design information correlated, figures out the change of temperature field around pipe. It can be carried on testing the temperature field of frozen soil without considering the effect of the oil temperature and a minus oil temperature offered. Watching the freezing and thawing process of ground temperature on cross section axes. season-frost deepness is changing within seven meters while pipe is running the former twenty-five years around. It is minishing year after year when the later twenty-five years, showing the season-frost soil is subsidizing year after year. In the former twenty-five years, the upper limit of perennial-frost soil is a falling trend year after year, meanwhile, the lower limit of it is a rising trend, showing the perennial-frost is retrogressing. By the 27th year, the perennial-frost soils turn to the season-frost soils completely. Therefore, in the condition of the global warming, frozen soil is rather affected, causing the perennial-frost turning to the season-frost until the whole. The oil temperature is not invariableness in the process of ground temperature changing. The changing law of ground temperature in the center of the pipe interface changes with the runtime,and increasing by degrees in the same depth, known from the temperature-depth curve made in the deepness direction of pipe cross section axes. Above 10 meters, the temperature changes obviously, and minishes gradually below 10 meters. The artificial limit ofˉfrozen soil minishes with the service time, showing it will rise year after year in the effect of oil temperature.
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