文献类型： 会议论文

第一作者： Luong J

作者： Luong J ¹ ; Destain M.F ² ; Mercatoris B.CN ³ ;

作者机构： 1.AgriculturelsLife plateform, Gembloux Agro-Bio Tech, University of Liege, 2 Passage des Deportes,5030 Gembloux (Belgium)

2.Department of Biosystem Engineering, Gembloux Agro-Bio Tech, University of Liege, 2 Passage des Deportes, 5030 Gembloux (Belgium)

3.Department of Biosystem Engineering, Gembloux Agro-Bio Tech, University of Liege, 2 Passagedes Deportes, 5030 Gembloux (Belgium)

关键词： Soil compaction;characterisation;soil structure and ultrasonic waves.

会议名称： Annual International Meeting of the American Society of Agricultural and Biological Engineers

主办单位：

页码： 4582-4593

摘要： The compaction is considered as one of the major factors of physical degradation of agricultural soils and results from the traffic of increasingly heavy machines. Mainly influenced by the soil type, the hydraulic status and the agricultural practices, the compaction phenomenon has harmful consequences such as the reduction of the soil fedility. Furthermore, the compaction phenomenon is quasi irreversible in the subsoil. It is therefore crucial to characterise the soil compaction level of agricultural soils. Nowadays, the quantification of soil compaction is mainly based on the measurement of the dry bulk density and the preconsolidation stress. These methods remain however long and expensive processes. In order to develop a rapid method for the quantification of the compaction level of agricultural soils, the propagation of ultrasonic waves in soil can be investigated since the signal is related to the soil microstructure. In this contribution, correlations are determined between the acoustic signatures of soil samples in function of their compaction level in wet and dry conditions. In order to reproduce different compaction levels in laboratory, oedometric tests are performed on unsaturated soil samples. In-situ samples collected from a conventionally tilled soil at different depths are also studied. The propagated signals are treated in both time and frequency domains in order to determine their propagation velocity and their attenuation spectrum. Different methods to extract the wave flight time are compared. The results are in agreement with the evolution of the dry bulk density with the compaction.

分类号： S-532