A new approach was proposed to describe settlement behavior of an unsaturated soil with subgrade filling for high-speed railway. Firstly, based on Terzaghi consolidation theory, equations considering the variation coe...A new approach was proposed to describe settlement behavior of an unsaturated soil with subgrade filling for high-speed railway. Firstly, based on Terzaghi consolidation theory, equations considering the variation coefficient of consolidation with void ratio and saturation for consolidation of an unsaturated soil under stage continuous loading were derived, and according to analytical solutions of equations, a formula for settlement computation under stage continuous loading was obtained. Then, combined with the width-to-height ratio of subgrade to compute ground reaction, and by means of in-situ plate loading curves, a correctional approach was presented for the analysis of nonlinear settlement of foundation. Also, the comparison between calculated and measured loadsettlement behavior for an unsaturated soil in Qingdao-Ji'nan high-speed railway was given to demonstrate the effectiveness and accuracy of the proposed approach. It can be noted that the presented solution can be used to predict the settlement of an unsaturated soil foundation under stage continuous loading in engineering design.展开更多
To investigate the impact of anaerobic soil disinfestation(ASD)treatment with different processing duration on tomato continuous cropping soil,a total of eight treatments were designed,which included two treatment tem...To investigate the impact of anaerobic soil disinfestation(ASD)treatment with different processing duration on tomato continuous cropping soil,a total of eight treatments were designed,which included two treatment temperatures of 10℃ and 30℃,and four treatment times of 3,4,5 and 7 weeks(w).The results showed that whether the temperature was 10℃ or 30℃,the pH values,TOC and available K contents in the soil treated by the ASD method were significantly increased(P<0.05),while the EC values and NO_(3)^(-)contents in soils treated by ASD were significantly reduced compared with the untreated group(P<0.05).The Fusarium oxysporum population in soils treated by ASD decreased with the extension of the treatment time.When the treatment temperature was 30℃,the effect on the removal of the NO_(3)^(-)that had accumulated in soils treated by ASD was significantly better than the treatment temperature of 10℃(P<0.05).When soil was treated by ASD for more than 5 w at 30℃,the NH4+content in soil was significantly increased(P<0.05)compared with the untreated soil.In conclusion,NO_(3)^(-)accumulation in soils could not be completely eliminated with treatment by ASD,even when the treatment time at 10℃ was prolonged.Whether the treatment temperature was 10℃ or 30℃,the F.oxysporum population in soils treated by ASD decreased significantly with the extension of the treatment time to more than 5 w compared with treatment only for only 3 w.展开更多
基金Project(2010G003-F)supported by the Research and Development Program for Technology of the Chinese Ministry of Railway
文摘A new approach was proposed to describe settlement behavior of an unsaturated soil with subgrade filling for high-speed railway. Firstly, based on Terzaghi consolidation theory, equations considering the variation coefficient of consolidation with void ratio and saturation for consolidation of an unsaturated soil under stage continuous loading were derived, and according to analytical solutions of equations, a formula for settlement computation under stage continuous loading was obtained. Then, combined with the width-to-height ratio of subgrade to compute ground reaction, and by means of in-situ plate loading curves, a correctional approach was presented for the analysis of nonlinear settlement of foundation. Also, the comparison between calculated and measured loadsettlement behavior for an unsaturated soil in Qingdao-Ji'nan high-speed railway was given to demonstrate the effectiveness and accuracy of the proposed approach. It can be noted that the presented solution can be used to predict the settlement of an unsaturated soil foundation under stage continuous loading in engineering design.
基金The Academic Support Project for Top Talents of Higher Education Subject(Major)in Anhui Province(gxbjZD2022077)The AgriculturalEcological Conservation and Pollution Control Key Laboratory of Anhui Province(FECPP201901)The High-level Talent Launch Foundationof the Applied Science Research Project of Bengbu University in 2024(2024YYX54QD).
文摘To investigate the impact of anaerobic soil disinfestation(ASD)treatment with different processing duration on tomato continuous cropping soil,a total of eight treatments were designed,which included two treatment temperatures of 10℃ and 30℃,and four treatment times of 3,4,5 and 7 weeks(w).The results showed that whether the temperature was 10℃ or 30℃,the pH values,TOC and available K contents in the soil treated by the ASD method were significantly increased(P<0.05),while the EC values and NO_(3)^(-)contents in soils treated by ASD were significantly reduced compared with the untreated group(P<0.05).The Fusarium oxysporum population in soils treated by ASD decreased with the extension of the treatment time.When the treatment temperature was 30℃,the effect on the removal of the NO_(3)^(-)that had accumulated in soils treated by ASD was significantly better than the treatment temperature of 10℃(P<0.05).When soil was treated by ASD for more than 5 w at 30℃,the NH4+content in soil was significantly increased(P<0.05)compared with the untreated soil.In conclusion,NO_(3)^(-)accumulation in soils could not be completely eliminated with treatment by ASD,even when the treatment time at 10℃ was prolonged.Whether the treatment temperature was 10℃ or 30℃,the F.oxysporum population in soils treated by ASD decreased significantly with the extension of the treatment time to more than 5 w compared with treatment only for only 3 w.
