To investigate the bearing capacity of a caisson foundation under combined vertical,horizontal and moment loadings,the three-dimensional finite element analyses of a circular caisson foundation in homogenous sandy soi...To investigate the bearing capacity of a caisson foundation under combined vertical,horizontal and moment loadings,the three-dimensional finite element analyses of a circular caisson foundation in homogenous sandy soil subjected to combined loadings are conducted.The caisson model has a depth to breadth ratio equaling one,and a soil-caisson interface friction coefficientμ=0.3.First,the responses of caisson foundations under uniaxial vertical loading V,horizontal loading H and moment loading M are examined.Moreover,the responses of caisson foundations under combined vertical-horizontal V-H,vertical-moment V-M and horizontal-moment H-M load space are studied and presented using normalized failure envelopes generated by the load-controlled method.Subsequently,the bearing behavior of caisson foundations under combined vertical-horizontal-moment V-H-M load space,as well as the kinematic mechanisms accompanying the failure under uniaxial and combined loading,are addressed and presented for different vertical load ratios V/Vu.Finally,three equations that approximate the three-dimensional shape of the failure locus are proposed,which provides a convenient means of calculating the bearing capacity of a caisson foundation subjected to uniaxial and combined vertical,horizontal and moment loadings.展开更多
Suction bucket foundations can be divided into four compartments by cruciform internal bulkheads,thereby yielding better capacity in certain conditions than those without internal bulkheads.As yet,no systematic study ...Suction bucket foundations can be divided into four compartments by cruciform internal bulkheads,thereby yielding better capacity in certain conditions than those without internal bulkheads.As yet,no systematic study has been conducted regarding the effects of cruciform internal bulkheads on the capacities of suction bucket foundations.In this study,we established a large number of finite element models of suction bucket foundations with and without cruciform internal bulkheads and of solid embedded circular foundations.We found the uniaxial capacities and failure modes of suction bucket foundations with various depth ratios to remain basically unaffected by internal bulkheads in uniform clays.However,in inhomogeneous clay with high strength heterogeneity,we observed the uniaxial moment and horizontal capacities and corresponding failure modes of suction bucket foundations with a low depth ratio to be obviously affected by internal bulkheads.In this case,the uniaxial moment capacities,in particular,as well as the horizontal capacities of suction bucket foundations with cruciform internal bulkheads become obviously greater than those without internal bulkheads.Under combined loading,we found the failure envelopes of suction bucket foundations with and without cruciform internal bulkheads and of solid circular foundation to also be basically consistent in uniform clays.However,in inhomogeneous clay with high strength heterogeneity,cruciform internal bulkheads can obviously change the shapes of the failure envelopes of bucket foundations with a small depth ratio.We conclude that when the acting vertical load or foundation depth is relatively small,suction bucket foundations with cruciform internal bulkheads can be subjected to larger moment and horizontal loads in soft clays with high strength heterogeneity.展开更多
This paper for the first time proposes an empirical framework for inclusive growth, under which policy :s-efficiency and distributive impacts can both be assessed. This paper applies this framework to China :s-rural i...This paper for the first time proposes an empirical framework for inclusive growth, under which policy :s-efficiency and distributive impacts can both be assessed. This paper applies this framework to China :s-rural infrastructure and a large sample of individual-level data, providing estimates of growth and distributive impacts of physical infrastructures of telephone and tap water in rural China. They all are found to promote rural income growth, helping narrow the rural-urban gap in China. More importantly, the poorer gained more than the richer from these infrastructures, implying benign distributive effects. This paper sheds light on the positive and important role in which infrastructure plays to promote inclusive growth in rural China.展开更多
In this paper,we present a novel oil level monitoring sensor based on string tilted fiber Bragg grating(TFBG).The measurement range and sensitivity of oil level monitoring can be modulated via changing the length and ...In this paper,we present a novel oil level monitoring sensor based on string tilted fiber Bragg grating(TFBG).The measurement range and sensitivity of oil level monitoring can be modulated via changing the length and number of string tilted fiber gratings.The transmission spectrum of string TFBGs immersed in oil changes obviously with the oil level variation.Experiments are conducted on three 2 cm-length serial TFBGs with the same tilted angle of 10o.A sensitivity of 3.28 dB/cm in the string TFBG sensor is achieved with good linearity by means of TFBG spectrum characteristic with peak-low value.The cladding mode transmission power and the amplitude of high order cladding mode resonance are nearly linear to the oil level variation.This kind of sensor is insensitive to temperature and attributed to be employed in extremely harsh environment oil monitoring.展开更多
First, the authors give a GrSbner-Shirshov basis of the finite-dimensional irre- ducible module Vq（λ） of the Drinfeld-Jimbo quantum group Uq（G2） by using the double free module method and the known GrSbner-Shirsh...First, the authors give a GrSbner-Shirshov basis of the finite-dimensional irre- ducible module Vq（λ） of the Drinfeld-Jimbo quantum group Uq（G2） by using the double free module method and the known GrSbner-Shirshov basis of Uq（G2）. Then, by specializing a suitable version of Uq （G2） at q = 1, they get a GrSbner-Shirshov basis of the universal enveloping algebra U（G2） of the simple Lie algebra of type G2 and the finite-dimensional irreducible U（G2）-module V（λ）.展开更多
基金The National Natural Science Foundation of China(No.51808112,51878160,51678145)the Natural Science Foundation of Jiangsu Province(No.BK20180155)。
文摘To investigate the bearing capacity of a caisson foundation under combined vertical,horizontal and moment loadings,the three-dimensional finite element analyses of a circular caisson foundation in homogenous sandy soil subjected to combined loadings are conducted.The caisson model has a depth to breadth ratio equaling one,and a soil-caisson interface friction coefficientμ=0.3.First,the responses of caisson foundations under uniaxial vertical loading V,horizontal loading H and moment loading M are examined.Moreover,the responses of caisson foundations under combined vertical-horizontal V-H,vertical-moment V-M and horizontal-moment H-M load space are studied and presented using normalized failure envelopes generated by the load-controlled method.Subsequently,the bearing behavior of caisson foundations under combined vertical-horizontal-moment V-H-M load space,as well as the kinematic mechanisms accompanying the failure under uniaxial and combined loading,are addressed and presented for different vertical load ratios V/Vu.Finally,three equations that approximate the three-dimensional shape of the failure locus are proposed,which provides a convenient means of calculating the bearing capacity of a caisson foundation subjected to uniaxial and combined vertical,horizontal and moment loadings.
基金supported by the National Natural Science Foundation of China(Nos.51479133,51109157)the Elite Scholar Program of Tianjin University(2017XRG0040)
文摘Suction bucket foundations can be divided into four compartments by cruciform internal bulkheads,thereby yielding better capacity in certain conditions than those without internal bulkheads.As yet,no systematic study has been conducted regarding the effects of cruciform internal bulkheads on the capacities of suction bucket foundations.In this study,we established a large number of finite element models of suction bucket foundations with and without cruciform internal bulkheads and of solid embedded circular foundations.We found the uniaxial capacities and failure modes of suction bucket foundations with various depth ratios to remain basically unaffected by internal bulkheads in uniform clays.However,in inhomogeneous clay with high strength heterogeneity,we observed the uniaxial moment and horizontal capacities and corresponding failure modes of suction bucket foundations with a low depth ratio to be obviously affected by internal bulkheads.In this case,the uniaxial moment capacities,in particular,as well as the horizontal capacities of suction bucket foundations with cruciform internal bulkheads become obviously greater than those without internal bulkheads.Under combined loading,we found the failure envelopes of suction bucket foundations with and without cruciform internal bulkheads and of solid circular foundation to also be basically consistent in uniform clays.However,in inhomogeneous clay with high strength heterogeneity,cruciform internal bulkheads can obviously change the shapes of the failure envelopes of bucket foundations with a small depth ratio.We conclude that when the acting vertical load or foundation depth is relatively small,suction bucket foundations with cruciform internal bulkheads can be subjected to larger moment and horizontal loads in soft clays with high strength heterogeneity.
基金funded by Bairen Program of Yunnan provincethe NSF Projects 71133004 and 71603026 of the National Natural Science Foundation of China+1 种基金Projects 2015M580055 and 2016T90048 of the China Postdoctoral Science FoundationYouth Scholars Program of Beijing Normal University
文摘This paper for the first time proposes an empirical framework for inclusive growth, under which policy :s-efficiency and distributive impacts can both be assessed. This paper applies this framework to China :s-rural infrastructure and a large sample of individual-level data, providing estimates of growth and distributive impacts of physical infrastructures of telephone and tap water in rural China. They all are found to promote rural income growth, helping narrow the rural-urban gap in China. More importantly, the poorer gained more than the richer from these infrastructures, implying benign distributive effects. This paper sheds light on the positive and important role in which infrastructure plays to promote inclusive growth in rural China.
基金supported by the National Natural Science Foundation of China (No.51079080)
文摘In this paper,we present a novel oil level monitoring sensor based on string tilted fiber Bragg grating(TFBG).The measurement range and sensitivity of oil level monitoring can be modulated via changing the length and number of string tilted fiber gratings.The transmission spectrum of string TFBGs immersed in oil changes obviously with the oil level variation.Experiments are conducted on three 2 cm-length serial TFBGs with the same tilted angle of 10o.A sensitivity of 3.28 dB/cm in the string TFBG sensor is achieved with good linearity by means of TFBG spectrum characteristic with peak-low value.The cladding mode transmission power and the amplitude of high order cladding mode resonance are nearly linear to the oil level variation.This kind of sensor is insensitive to temperature and attributed to be employed in extremely harsh environment oil monitoring.
基金supported by the National Natural Science Foundation of China(Nos.11061033,11361056)
文摘First, the authors give a GrSbner-Shirshov basis of the finite-dimensional irre- ducible module Vq（λ） of the Drinfeld-Jimbo quantum group Uq（G2） by using the double free module method and the known GrSbner-Shirshov basis of Uq（G2）. Then, by specializing a suitable version of Uq （G2） at q = 1, they get a GrSbner-Shirshov basis of the universal enveloping algebra U（G2） of the simple Lie algebra of type G2 and the finite-dimensional irreducible U（G2）-module V（λ）.
