Multi-layer slopes are widely found in clay residue receiving fields.A generalized horizontal slice method(GHSM)for assessing the stability of multi-layer slopes that considers the energy dissipation between adjacent ...Multi-layer slopes are widely found in clay residue receiving fields.A generalized horizontal slice method(GHSM)for assessing the stability of multi-layer slopes that considers the energy dissipation between adjacent horizontal slices is presented.In view of the upper-bound limit analysis theory,the energy equation is derived and the ultimate failure mode is generated by comparing the sliding surface passing through the slope toe(mode A)with that below(mode B).In addition,the influence of the number of slices on the stability coefficients in the GHSM is studied and the stable value is obtained.Compared to the original method(Chen’s method),the GHSM can acquire more precise results,which takes into account the energy dissipation in the inner sliding soil mass.Moreover,the GHSM,limit equilibrium method(LEM)and numerical simulation method(NSM)are applied to analyze the stability of a multi-layer slope with different slope angles and the results of the safety factor and failure mode are very close in each case.The ultimate failure modes are shown to be mode B when the slope angle is not more than 28°.It illustrates that the determination of the ultimate sliding surface requires comparison of multiple failure modes,not only mode A.展开更多
Due to urban construction and renovation projects,a large amount of construction and demolition waste(CDW)is increasing year by year in China.Among them,soil-brick mixture(SBM)is most widely landfilled because many ol...Due to urban construction and renovation projects,a large amount of construction and demolition waste(CDW)is increasing year by year in China.Among them,soil-brick mixture(SBM)is most widely landfilled because many older brick buildings were constructed in the last century(Zhang et al.,2022;Xu et al.,2021).Since the SBM is composed of two kinds of geotechnical materials,its mechanical properties are more complex than those of the single material.They depend not only on the mechanical properties of the individual components such as soil and brick,but also on the relative content of these components and the shape of the coarse particles(Zhu et al.,2021).The shear properties of SBM directly affect the stability of slope and paving engineering;therefore,it is significant to study the mechanical properties of SBM.展开更多
Rock bolts are widely employed as an effective and efficient reinforcement method in geotechnical engineering.Sandwich composite structures formed by hard rock and weak rock are often encountered in practical projects...Rock bolts are widely employed as an effective and efficient reinforcement method in geotechnical engineering.Sandwich composite structures formed by hard rock and weak rock are often encountered in practical projects.Furthermore,the spatial structure of the rock mass has a direct influence on the effect of the anchorage support.To investigate the impact of rock mass structure on the mechanical characteristics of anchorage interfaces,pull-out tests on reinforced specimens with different mudstone thicknesses and fracture dip angles are conducted.The experimental results indicate that the percentage of mudstone content and fracture dip angle have a significant influence on the pullout load of the samples.A weaker surrounding rock results in a lower peak load and a longer critical anchorage length,and vice versa.The results also show that 70%mudstone content can be considered a critical condition for impacting the peak load.Specifically,the percentage of mudstone content has a limited influence on the variation in the peak load when it exceeds 70%.Optical fiber deformation results show that compared to the rock mass with fracture dip angles of 0°and 60°,the rock mass with a fracture dip angle of 30°has a more uniformly distributed force at the anchorage interface.When the fracture dip angle exceeds 60°,the dip angle is no longer a key indicator of peak load.The accuracy of the experimentally obtained load-displacement curves is further verified although numerical simulation using the discrete element method.展开更多
Monitoring data show that many landslides in the Three Gorges region,China,undergo step-like displacements in response to the managed,quasi-sinusoidal annual variations in reservoir level.This behavior is consistent w...Monitoring data show that many landslides in the Three Gorges region,China,undergo step-like displacements in response to the managed,quasi-sinusoidal annual variations in reservoir level.This behavior is consistent with motion initiating when the reservoir water level falls below a critical level that is intrinsic to each landslide,with the subsequent displacement rate of the landslide being proportional to the water depth below that critical level.Most motion terminates when the water level rises back above the critical level,so the annual step size is the time integral of the instantaneous displacement rate.These responses are incorporated into a differential equation that is easily calibrated with monitoring data,allowing prediction of landslide movement from actual or anticipated reservoir level changes.Model successes include(1)initiation and termination of the annual sliding steps at the critical reservoir level,producing a series of steps;(2)prediction of variable step size,year to year;and(3)approximate prediction of the shape and size of each annual step.Annual rainfall correlates poorly with step size,probably because its effect on groundwater levels is dwarfed by the 30 m annual variations in the level of the Three Gorges Reservoir.Viscous landslide behavior is suggested.展开更多
基金support provided by the National Key R&D Program of China(No.2017YFC1501304)the National Natural Science Foundation of China(Nos.42090054,41922055 and 41931295)the Fundamental Research Funds for the Central Universities,China University of Geosciences(Wuhan)(No.CUGGC09).
文摘Multi-layer slopes are widely found in clay residue receiving fields.A generalized horizontal slice method(GHSM)for assessing the stability of multi-layer slopes that considers the energy dissipation between adjacent horizontal slices is presented.In view of the upper-bound limit analysis theory,the energy equation is derived and the ultimate failure mode is generated by comparing the sliding surface passing through the slope toe(mode A)with that below(mode B).In addition,the influence of the number of slices on the stability coefficients in the GHSM is studied and the stable value is obtained.Compared to the original method(Chen’s method),the GHSM can acquire more precise results,which takes into account the energy dissipation in the inner sliding soil mass.Moreover,the GHSM,limit equilibrium method(LEM)and numerical simulation method(NSM)are applied to analyze the stability of a multi-layer slope with different slope angles and the results of the safety factor and failure mode are very close in each case.The ultimate failure modes are shown to be mode B when the slope angle is not more than 28°.It illustrates that the determination of the ultimate sliding surface requires comparison of multiple failure modes,not only mode A.
基金supported by the National Natural Science Fund of China(Nos.42090054,41931295)the Natural Science Foundation of Hubei Province of China(No.2022CFA002)。
文摘Due to urban construction and renovation projects,a large amount of construction and demolition waste(CDW)is increasing year by year in China.Among them,soil-brick mixture(SBM)is most widely landfilled because many older brick buildings were constructed in the last century(Zhang et al.,2022;Xu et al.,2021).Since the SBM is composed of two kinds of geotechnical materials,its mechanical properties are more complex than those of the single material.They depend not only on the mechanical properties of the individual components such as soil and brick,but also on the relative content of these components and the shape of the coarse particles(Zhu et al.,2021).The shear properties of SBM directly affect the stability of slope and paving engineering;therefore,it is significant to study the mechanical properties of SBM.
基金supported by the National Natural Science Foundation of China(Nos.42090054,41922055 and 41931295)the Research Project of China Three Gorges Corporation(No.2019073)+1 种基金the Zhejiang Huadong Construction Engineering Co.,Ltd.(No.KY2019-HDJS-07)the Key Research and Development Program of Hubei Province of China(No.2022CFA002)。
文摘Rock bolts are widely employed as an effective and efficient reinforcement method in geotechnical engineering.Sandwich composite structures formed by hard rock and weak rock are often encountered in practical projects.Furthermore,the spatial structure of the rock mass has a direct influence on the effect of the anchorage support.To investigate the impact of rock mass structure on the mechanical characteristics of anchorage interfaces,pull-out tests on reinforced specimens with different mudstone thicknesses and fracture dip angles are conducted.The experimental results indicate that the percentage of mudstone content and fracture dip angle have a significant influence on the pullout load of the samples.A weaker surrounding rock results in a lower peak load and a longer critical anchorage length,and vice versa.The results also show that 70%mudstone content can be considered a critical condition for impacting the peak load.Specifically,the percentage of mudstone content has a limited influence on the variation in the peak load when it exceeds 70%.Optical fiber deformation results show that compared to the rock mass with fracture dip angles of 0°and 60°,the rock mass with a fracture dip angle of 30°has a more uniformly distributed force at the anchorage interface.When the fracture dip angle exceeds 60°,the dip angle is no longer a key indicator of peak load.The accuracy of the experimentally obtained load-displacement curves is further verified although numerical simulation using the discrete element method.
基金the National Key R&D Program of China(Nos.2018YFC1507200,2017YFC1501304)the National Science Fund for Excellent Young Scholars of China(No.41922055)。
文摘Monitoring data show that many landslides in the Three Gorges region,China,undergo step-like displacements in response to the managed,quasi-sinusoidal annual variations in reservoir level.This behavior is consistent with motion initiating when the reservoir water level falls below a critical level that is intrinsic to each landslide,with the subsequent displacement rate of the landslide being proportional to the water depth below that critical level.Most motion terminates when the water level rises back above the critical level,so the annual step size is the time integral of the instantaneous displacement rate.These responses are incorporated into a differential equation that is easily calibrated with monitoring data,allowing prediction of landslide movement from actual or anticipated reservoir level changes.Model successes include(1)initiation and termination of the annual sliding steps at the critical reservoir level,producing a series of steps;(2)prediction of variable step size,year to year;and(3)approximate prediction of the shape and size of each annual step.Annual rainfall correlates poorly with step size,probably because its effect on groundwater levels is dwarfed by the 30 m annual variations in the level of the Three Gorges Reservoir.Viscous landslide behavior is suggested.