Key Tecnological Study On Measuring Soil Aggregate Stability Using Ultrasonic Systems

Soil aggregate is the basic component of soil structure unit. The stability of soil structure, in most case, refers to the water stability of the aggregate. On the measurement of soil aggregate stability, many scholars according to the needs of their work, their research methods and measuring method are put forward.For the existing soil aggregate stability quantitative assessment system using ultrasonic dispersion can’t control oil temperature rapid rise in the process of the experimental, is limited by soil temperature upper bound, every dispersion test can not last too long time, and the soil sample can’t completely dispersed in only one test. So the same soil sample needs more rounds test to completely dispersed.In this paper, for the problems in the existing system, the main subjects and conclusions of the research were as follow:(1)Designed a new double wall container. For the demand to strictly control the temperature of the reaction solution requirements, designed a new double wall container. Through the sealing property test, circulatory test and the cooling performance test, indicates that the new experimental design is reasonable, and meet the expected design requirements. And its cooling performance curve obtained by experiment, prepared the basic reference data for further tests.(2)Ultrasonic measurement system is designed. According to the designed new experimental container, to form a complete set of experimental equipment, devices such as ultrasonic, ultrasonic probe of the instrument and automatic data acquisition system, circulating cooling liquid temperature measuring probe, was designed and selected. Through the experiment measured the ultrasonic instrument no-load loss test and ultrasonic instrument vibrator output power level in different depth testing, proved the validity of the test container to control the temperature of reaction solution, hardware platform more quickly and efficiently was set up for soil aggregate dispersed energy measurement.(3)Designed the ultrasonic energy in soil measurement method of theoretical calculation and experimental steps. In the case of the HN soil samples, the dispersing process energy change is analyzed in detail, it was concluded that the dispersion energy was about 183 J/g.(4)Ultrasonic measurement system performance further verification. Using two methods comparative studied the stability of different soil samples, and analyzed the correlation and difference between two methods, it was concluded that stronger stability soil sample in two kinds of methods had the same result, but the weaker stability, parts of the soil samples was completely dispersed in a short time causing the results appeared difference, in other words, the weaker stability soil sample cannot use the existing ultrasonic dispersion method to analyze its stability. The output power of ultrasonic instruments available for weaker stability soil samples was too large. This can be used as a judgment whether the soil samples fit for existing ultrasonic dispersing methods to analyze the stability. Through to the soil particle size distribution of dynamic measurement experiment design, and four kinds of soil samples HN, ZJ, CQ, JX were tested, they were drawn to the dynamic distribution of particle size. Verify the feasibility of the test system.