The objective of our work was to determine the influence of UV radiation and environmental temperature on the strength and rheological characteristics of multi-layer agricultural packaging foils. A Finite-Element-Meth...The objective of our work was to determine the influence of UV radiation and environmental temperature on the strength and rheological characteristics of multi-layer agricultural packaging foils. A Finite-Element-Method （FEM） model was developed for analyzing the foil-silo interactions at different environmental conditions. The constitutive equation of the different foils was based on Poynting-Thomson model. The measured relaxation curve was found to have a close correlation both for -10℃ and 45 ℃ with the calculated results. The result of the FEM modeling shows that both the vertical distortion of the tubular foil peak and the highest reduced tension decrease with the increase of the temperature. Therefore, the probability of foil tears increases with the decrease of the temperature because the tension strength of the tubular foil decreases under cold conditions.展开更多
An ancient landslide, situated in Deqin County, Yunnan Province, China, was used to investigate the reactivation by water infiltration. This study considers the infiltration process and landslide stability using finit...An ancient landslide, situated in Deqin County, Yunnan Province, China, was used to investigate the reactivation by water infiltration. This study considers the infiltration process and landslide stability using finite-element method(FEM)-based models. The results show that the reactivation of old landslide deposit was triggered by the long-term leakage of diversion ditch before October 2012, and the reactivation was triggered again by the intense rainfall on 7-9 October 2012. The old cracks, which formed in the earlier reactivation of landslide, played a key role for the rainfall infiltration. They offered a preferential path for much more rainfall to infiltrate fast into deep soil, and caused wetting front to move down faster in landslide. The old slip zone with lower permeability was another important factor to cause the infiltrated water to accumulate and form a high pore water pressure above slip zone. Then the high pore water pressure decreased the shear strength of slip zone and triggered the reactivation of the old landslide deposit again.展开更多
文摘The objective of our work was to determine the influence of UV radiation and environmental temperature on the strength and rheological characteristics of multi-layer agricultural packaging foils. A Finite-Element-Method （FEM） model was developed for analyzing the foil-silo interactions at different environmental conditions. The constitutive equation of the different foils was based on Poynting-Thomson model. The measured relaxation curve was found to have a close correlation both for -10℃ and 45 ℃ with the calculated results. The result of the FEM modeling shows that both the vertical distortion of the tubular foil peak and the highest reduced tension decrease with the increase of the temperature. Therefore, the probability of foil tears increases with the decrease of the temperature because the tension strength of the tubular foil decreases under cold conditions.
基金supported by the National Natural Science Foundation of China (Grant Nos. 41472274, 41672300)Independent Subject Foundation of SKLGP (SKLGP2017Z010)
文摘An ancient landslide, situated in Deqin County, Yunnan Province, China, was used to investigate the reactivation by water infiltration. This study considers the infiltration process and landslide stability using finite-element method(FEM)-based models. The results show that the reactivation of old landslide deposit was triggered by the long-term leakage of diversion ditch before October 2012, and the reactivation was triggered again by the intense rainfall on 7-9 October 2012. The old cracks, which formed in the earlier reactivation of landslide, played a key role for the rainfall infiltration. They offered a preferential path for much more rainfall to infiltrate fast into deep soil, and caused wetting front to move down faster in landslide. The old slip zone with lower permeability was another important factor to cause the infiltrated water to accumulate and form a high pore water pressure above slip zone. Then the high pore water pressure decreased the shear strength of slip zone and triggered the reactivation of the old landslide deposit again.
