| This thesis is completed supported by National Science Foundation'A study on the THM-coupled-effect mechanism in the system of new earth-energy exchange pile, soil and water'.(No. 40472134) . The thermal conductivity(TC) of soil and rock is an very important thermal physics parameter, and is also an important parameter for many problems of engineering technology and study. The study on TC of the geotechnical materials was an important side of the research on the heat pump technique from the earth[1], the geology disposal of the high radioactive wastes and buffer materials[2],(bentonite,etc. [3]) the heat distribution of the subsurface cable[4],the moisture migration of the soil temperature field[5.6],the permafrost engineering[7],the temperture field with buried the heat tubing[8],the changes of foundation temperture field[9], etc., which directly influenced the solution and the design of the engineer problem above. Especially, the shallow terrestrial heat pump to be widely applied[10], it became the focus that the measure of the TC of the geotechnical materials and the change with the temperature.There are two testing methods of TC: steady method and unsteady method. The unsteady method is also called the probe method. The advantage of this method is little time required (usually from several minutes to tens minutes). The equipment used in this experiment is QTM testing equipment imported by Japan. The principle is base on flat probe for the measurement TC which is instable. When the experiment is in process, the machine is able to calculate and show the thermal conductivity autoably. The theory has been introduced simply in this article. In this experiment, we apply this machine to acquire TC of sand, soil , and rock and then transform the data to chat. Then make a curve and seek the equation of the curve. Analysis the relationship between different TC and temperature and the trend which shows that the TC change as the temperature changes. The result of the experiment shows: The TC of sand (t> 0℃) increases as the temperature increase, since the regress coefficient is positive. The thermal conductivity of soil increases as the temperature reduced, since regress coefficient is negative. The thermal conductivity of rock increases as the temperature reduced, since regress coefficient is negative. Generally speaking, the relationship between thermal conductivity and temperature approximately can be seen linear. The linear relationship as follows:TC and temperature's relationsh ip in unsaturated soil 1 K=-0.0036t+1.5556 Unit [w∕(m·K)]TC and temperature's relationsh ip in unsaturated soil 2 K=-0.0001t+1.5058 Unit [w∕(m·K)]TC and temperature's relationsh ip in saturated soil 1 K=-0.0002t+1.5264 Unit [w∕(m·K)]TC of rock increases as the temperature reduced.TC and temperature's relationsh ip in unsaturated rock : K= - 0.0072t+2.5041 Unit [w∕(m·K)]TC and temperature's relationsh ip in saturated rock: K= - 0.0053t+2.204 Unit [w∕(m·K)]The thermal conductivity (TC) of the sand, clay and rock were measured with QTM-D2. It was discussed that the effect of different experiments size and the conditions of saturated sample, and then it was studied that the size error of TC among different samples through experimental results and numerical simulation, which offered solution to the measure on the TC of the geotechnical materials in site. As we measure TC with the heat line method, the effect of sample size is limited, such as the measurement results on the different Geometry size approaches very much. According to the domestic and international study fact on the empirical relation of TC and temperature, Based on a large number of measure data and numerical calculation, it was concluded that the empirical relation between the temperature and TC at the condition of normal temperature, and it was put forward that the thermal variance coefficientβ. The values ofβof geotechnical materials are small, Mostly in 10-3 magnitude, and the curve of TC and temperature is approximate Linearity. There was important meaning that the leading-out of the coefficient and the experimental relationship to the understanding on the TC of the geotechnical materials in north China, and the temperature simulation programming, as well.Paper aim at the lack of studying on WSHP, a set of combine instrument to imitate WSHP was established and relevant simulation experiment was carried out. The experiment principle, test-bed composition, experimental sample preparation process, experimental steps and the various experimental equipment design parameters were introduced. The experimental results were analyzed and simulated. Through controlling different temperature and different recharging water volume, we found the following heat transfer characteristics: Increasing water recharging volume is less than the impact of increasing water recharging temperature on the surrounding sand temperature. The thermal diffusion of recharging water down is stronger than upward. Through controlling recharging water volume and temperature, the affected areas of sand temperature in the horizontal and vertical direction was drawn on, Which provided reference data for the development of water-source heat pump technology. Two -dimensional temperature field was simulated and contrasted with water recharge experiment data. According to results of the experiment, the TC was verified sand by the Fourier's Law, and the practical significance of Indoor-water source heat pump simulator and theory analysis on the water-source heat pump's design was discussed.
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