Soil improvement methods

Abstract

The present invention provides a soil improvement method that eliminates the need for or reduces the amount of soil improvement materials such as solidifying agents, allows for the continuous and large-scale processing of soil, and stabilizes the quality of the improved soil. [Solution] A soil improvement method using a mixing apparatus including a soil transport means, an improved soil transport means, and a mixing means, comprising the steps of: acquiring data relating to the quality of the original soil; preparing improved soil by mixing the original soil at an arbitrarily determined mixing ratio; acquiring image data of the improved soil; obtaining data relating to the particle size distribution of the improved soil from the image data of the improved soil, and if the data relating to the particle size distribution of the improved soil does not satisfy predetermined conditions, adjusting the mixing ratio, wherein the soil improvement method determines the transport mass per unit time (converted to dry mass) of each original soil using the quality data, and adjusts the mixing ratio using the numerical value of the transport mass.

Claims

1. Soil transport means for transporting the original soil, provided for each of two or more types of original soil, A means for transporting improved soil, which is a mixture of two or more of the above-mentioned original soils, A soil improvement method that continuously performs soil improvement treatment using a mixing apparatus that includes a mixing means for mixing two or more of the above-mentioned raw soils, A quality data acquisition process to acquire quality data for each of the two or more types of raw soil described above, A mixing process in which two or more of the above-mentioned raw soils are mixed in an arbitrarily determined mixing ratio to prepare improved soil with improved soil properties, Image data acquisition process to obtain image data of the improved soil described above, After obtaining data on the particle size distribution of the improved soil from the image data of the improved soil, if the data on the particle size distribution of the improved soil satisfies predetermined conditions, the mixing process is continued. If the data on the particle size distribution of the improved soil does not satisfy the conditions, a mixing ratio adjustment process is performed to adjust the mixing ratio in the mixing process so that the data on the particle size distribution of the improved soil satisfies the conditions. Includes, The above quality data includes data on the particle size distribution of the raw soil, the wet density of the raw soil, the water content of the raw soil, and the volume of raw soil transported per unit time. A soil improvement method characterized in that, in the mixing ratio adjustment step, the transported mass per unit time (converted to dry mass) of each raw soil is determined using the above quality data, and the mixing ratio (ratio of dry mass) in the mixing step is adjusted using the value of said transported mass to satisfy the above conditions.

2. The above mixing means is a transfer section having a step for transferring the original soil, which is being transported by the above soil transport means, to the above improved soil transport means. The soil improvement method according to claim 1, wherein the above-mentioned raw soil is transferred from the above-mentioned transfer section to the above-mentioned improved soil transfer means, and the above-mentioned raw soil is mixed with the above-mentioned raw soil or a mixture of two or more types of raw soil transferred by the above-mentioned improved soil transfer means, thereby continuously performing soil improvement treatment.

3. The soil improvement method according to claim 1 or 2, wherein the data relating to the particle size distribution of the improved soil includes a uniformity coefficient and a curvature coefficient.

4. The raw soils mixed in the above mixing process consist of two types of soil (soil A and soil B). In the above mixing ratio adjustment step, after determining the transport mass per unit time (converted to dry mass) of soil A and soil B using the following formulas (1) to (2), The uniformity coefficient U of the improved soil calculated using the following formulas (6) to (7) ｃ and the curvature coefficient U' of the improved soil Ｃ The soil improvement method according to claim 3, wherein the mixing ratio (ratio of dry mass (a:b)) of soil A and soil B is adjusted to satisfy the above conditions. WA=ar ａｔ / (1+ / ) ａ / 100)・・・(1) (In formula (1), WA is the transported mass of soil A per unit time (converted to dry mass), α is the transported volume of soil A per unit time, ρ ａｔ w is the wet density of soil A mentioned above. ａ (This is the water content of soil A mentioned above.) WB=wp ｂｔ / (1+ / ) ｂ / 100)・・・(2) (In formula (2), WB is the conveyance mass per unit time of the above soil B (in terms of dry mass), β is the conveyance volume per unit time of the above soil B, ρ ｂｔ is the wet density of the above soil B, w ｂ is the water content ratio of the above soil B.) Uc=D′ ６０ / T １０ ・・・(6) (In formula (6), D' １０ and D' ６０ These represent the 10% and 60% passage diameters, respectively, in the particle size accumulation curve of the improved soil. U′ Ｃ =(D′ ３０ ) ２ / {(D′ １０ )×(D′ ６０ )}・・・(7) (In formula (7), D' １０ , D' ３０ and D' ６０ These represent the 10% passage diameter, 30% passage diameter, and 60% passage diameter, respectively, in the particle size accumulation curve of the improved soil described above.

5. The soil improvement method according to claim 3, wherein the above conditions are the following conditions (1) to (2). (1) The above equalization coefficient exceeds 10.

0. (2) The coefficient of curvature is greater than 1.0 and less than 3.0.

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