Loess has distinctive characteristics,leading to frequent landslide disasters and posing serious threats to the lives and properties of local re sidents.The involvement of water repre sents a critical factor in induci...Loess has distinctive characteristics,leading to frequent landslide disasters and posing serious threats to the lives and properties of local re sidents.The involvement of water repre sents a critical factor in inducing loess landslides.This study focuses on three neighboring cities sequentially situated on the Loess Plateau along the direction of aeolian deposition of loess,namely Lanzhou,Dingxi,and Tianshui,which are densely populated and prone to landslide disasters.The variations in hydraulic properties,including water retention capacity and permeability,are investigated through Soil Water Characteristic Curve(SWCC)test and hydraulic conductivity test.The experimental findings revealed that Tianshui loess exhibited the highest water retention capacity,followed by Dingxi loess,while Lanzhou loess demonstrated the lowest water retention capacity.Contrastingly,the results for the saturated permeability coefficient were found to be the opposite:Tianshui loess showed the lowest permeability,whereas Lanzhou loess displayed the highest permeability.These results are supported and analyzed by scanning electron microscopy(SEM)observation.In addition,the water retention capacity is mathematically expressed using the van Genuchten model and extended to predict unsaturated hydraulic properties of loess.The experimental results exhibit a strong accordance with one another and align with the regional distribution patterns of disasters.展开更多
The influence of temperature on the engineered properties of bentonite-sand mixtures (B/S) is of major concern in the design of engineered barriers in underground repositories for high-level radioactive waste dispos...The influence of temperature on the engineered properties of bentonite-sand mixtures (B/S) is of major concern in the design of engineered barriers in underground repositories for high-level radioactive waste disposal. We experimentally studied the influence of temperature on soil unsaturated hydraulic properties related to water holding capacity and permeability of GMZ B/S in China. The vapor equilibrium method and water infiltration apparatus were used to measure the soil water characteristic curve (SWCC) and unsaturated hydraulic conductivity (k). The results show that the SWCC under different temperatures from 20℃ to 60 ℃ tends to be the same. Temperature influence on unsaturated permeability is more relevant at low suctions, no clear effect is detected below a degree of saturation of 74%, and experimental data show that temperature dependence on unsaturated permeability is small.展开更多
Using magnetorheological (MR) fluids in hydraulic engine mount for damping vehicle noise and vibration is opposed firstly, the structure of passive type and its mechanical model are described. The analysis of the expe...Using magnetorheological (MR) fluids in hydraulic engine mount for damping vehicle noise and vibration is opposed firstly, the structure of passive type and its mechanical model are described. The analysis of the experimental data show that the dynamic characteristics of MR mount such as dynamic stiffness and loss angles vary distinctly as the excitation frequency, and MR fluids as one type of attracting controllable fluids are fit for hydraulic engine mounts. The author advises to work out potentialities of MR fluids, the semi control or active control MR fluids filled hydraulic engine mount must be developed.展开更多
基金the financial support for the research presented in this paper from National Natural Science Foundation of China(42201142,42067066,51778590)。
文摘Loess has distinctive characteristics,leading to frequent landslide disasters and posing serious threats to the lives and properties of local re sidents.The involvement of water repre sents a critical factor in inducing loess landslides.This study focuses on three neighboring cities sequentially situated on the Loess Plateau along the direction of aeolian deposition of loess,namely Lanzhou,Dingxi,and Tianshui,which are densely populated and prone to landslide disasters.The variations in hydraulic properties,including water retention capacity and permeability,are investigated through Soil Water Characteristic Curve(SWCC)test and hydraulic conductivity test.The experimental findings revealed that Tianshui loess exhibited the highest water retention capacity,followed by Dingxi loess,while Lanzhou loess demonstrated the lowest water retention capacity.Contrastingly,the results for the saturated permeability coefficient were found to be the opposite:Tianshui loess showed the lowest permeability,whereas Lanzhou loess displayed the highest permeability.These results are supported and analyzed by scanning electron microscopy(SEM)observation.In addition,the water retention capacity is mathematically expressed using the van Genuchten model and extended to predict unsaturated hydraulic properties of loess.The experimental results exhibit a strong accordance with one another and align with the regional distribution patterns of disasters.
基金Funded by the Chinese National Defense Science and Industry(No.2007[834])
文摘The influence of temperature on the engineered properties of bentonite-sand mixtures (B/S) is of major concern in the design of engineered barriers in underground repositories for high-level radioactive waste disposal. We experimentally studied the influence of temperature on soil unsaturated hydraulic properties related to water holding capacity and permeability of GMZ B/S in China. The vapor equilibrium method and water infiltration apparatus were used to measure the soil water characteristic curve (SWCC) and unsaturated hydraulic conductivity (k). The results show that the SWCC under different temperatures from 20℃ to 60 ℃ tends to be the same. Temperature influence on unsaturated permeability is more relevant at low suctions, no clear effect is detected below a degree of saturation of 74%, and experimental data show that temperature dependence on unsaturated permeability is small.
文摘Using magnetorheological (MR) fluids in hydraulic engine mount for damping vehicle noise and vibration is opposed firstly, the structure of passive type and its mechanical model are described. The analysis of the experimental data show that the dynamic characteristics of MR mount such as dynamic stiffness and loss angles vary distinctly as the excitation frequency, and MR fluids as one type of attracting controllable fluids are fit for hydraulic engine mounts. The author advises to work out potentialities of MR fluids, the semi control or active control MR fluids filled hydraulic engine mount must be developed.