2007 Vol. 15, No. 4
2007, 15(4): 433-440.
The Fen-Wei basin is the most serious area of the ground fissure formation in China.This paper summarizes the distribution regularity of ground fissures in the basin.It analyses several key questions in the formation of ground fissures and emphasizes the origin of geotectonic ground fissures,puts forward some research ways as follows.By multi-disciplinary method,the distribution regularity of ground fissures and the relations to active tectonics are researched,and the tectonic ground fissures geological structural model is built.Through the modern numerical simulation with the high-precision observation techniques,the mechanical mechanics of ground fissures started by tectonization as well as the coupling rupture mechanics of tectonization and pumping actions are studied.Based on the observation data from GPS,the formation of the ground fissures on Qinghai-Tibet continent and the continent in north China,the intrinsic relations between regional ground fissures and the Chinese continental dynamics are studied,and the mechanism and model of continental drive force and the geological hazard are disclosed.
The Fen-Wei basin is the most serious area of the ground fissure formation in China.This paper summarizes the distribution regularity of ground fissures in the basin.It analyses several key questions in the formation of ground fissures and emphasizes the origin of geotectonic ground fissures,puts forward some research ways as follows.By multi-disciplinary method,the distribution regularity of ground fissures and the relations to active tectonics are researched,and the tectonic ground fissures geological structural model is built.Through the modern numerical simulation with the high-precision observation techniques,the mechanical mechanics of ground fissures started by tectonization as well as the coupling rupture mechanics of tectonization and pumping actions are studied.Based on the observation data from GPS,the formation of the ground fissures on Qinghai-Tibet continent and the continent in north China,the intrinsic relations between regional ground fissures and the Chinese continental dynamics are studied,and the mechanism and model of continental drive force and the geological hazard are disclosed.
2007, 15(4): 439-544.
The goal is providing optimization design based on clear performance about the landslide anchored arch anti-slide pile wall supporting structure system.We take use of advanced design ideas based on the performance structure optimization,the computer information processing technology and the intelligent decision-making technology.We study the influence of the structure system stress by the reasonable arrangement of anchored arch anti-slide pile wall supporting structures,and study the numerical computational method and the optimized model,and explore the assess method and the appraisal model,develop design software based on the performance anchored arch anti-slide pile wall supporting structure system optimization.Then provide explicit parameters and superior supporting plan with security,economy,and performance for the landslide government What we are studying has the positive significant roles on solving the stress system choice and the arrangement,the waste and the property damage.
The goal is providing optimization design based on clear performance about the landslide anchored arch anti-slide pile wall supporting structure system.We take use of advanced design ideas based on the performance structure optimization,the computer information processing technology and the intelligent decision-making technology.We study the influence of the structure system stress by the reasonable arrangement of anchored arch anti-slide pile wall supporting structures,and study the numerical computational method and the optimized model,and explore the assess method and the appraisal model,develop design software based on the performance anchored arch anti-slide pile wall supporting structure system optimization.Then provide explicit parameters and superior supporting plan with security,economy,and performance for the landslide government What we are studying has the positive significant roles on solving the stress system choice and the arrangement,the waste and the property damage.
2007, 15(4): 441-447.
There are many ground fractures in Weihe basin as a result of its special geological environment.Based on the detailed investigation,distributive summary of ground fractures is discussed.The basic feature is analyzed in detail.The reason why the ground fractures are formed is discussed initially.The most of the total 196 ground fractures in Weihe basin are around the faultages,which are accordant and correlative with the faultages of Weihe basin.The basic feature is mainly morphological character and distribution.The ground fractures express themselves at land surface as straight line,S and polygonal line.Section plane can be characterized that the upside is wide and the under-part is narrow,inclination angles are relatively steep.The distribution of ground fractures can be characterized as directional,ringent and netlike.The ground fractures of Weihe basin are mainly tectonic fissures and controlled by the faultages of Weihe basin.Groundwater,surface water,goaf and settlement of loess are induction factors.
There are many ground fractures in Weihe basin as a result of its special geological environment.Based on the detailed investigation,distributive summary of ground fractures is discussed.The basic feature is analyzed in detail.The reason why the ground fractures are formed is discussed initially.The most of the total 196 ground fractures in Weihe basin are around the faultages,which are accordant and correlative with the faultages of Weihe basin.The basic feature is mainly morphological character and distribution.The ground fractures express themselves at land surface as straight line,S and polygonal line.Section plane can be characterized that the upside is wide and the under-part is narrow,inclination angles are relatively steep.The distribution of ground fractures can be characterized as directional,ringent and netlike.The ground fractures of Weihe basin are mainly tectonic fissures and controlled by the faultages of Weihe basin.Groundwater,surface water,goaf and settlement of loess are induction factors.
2007, 15(4): 448-452.
Tectonic background and modern stress field of the Shanxi garben system are formulated.The characteristics of the ground fissures developed in the area are generalized.Based on the investigation,a type of specific shear-crush ground fissures has been found.This ground fissure locates in E Mei Platform of the Shanxi garben system.It appears intensive shear and crush deformation-the ground and wall buckle and dislocate.This feature does not agree with other ground fissures developed in the area.According the features of ground fissures and region tectonic stress field,the formation mechanism of the special ground fissure has been discussed.
Tectonic background and modern stress field of the Shanxi garben system are formulated.The characteristics of the ground fissures developed in the area are generalized.Based on the investigation,a type of specific shear-crush ground fissures has been found.This ground fissure locates in E Mei Platform of the Shanxi garben system.It appears intensive shear and crush deformation-the ground and wall buckle and dislocate.This feature does not agree with other ground fissures developed in the area.According the features of ground fissures and region tectonic stress field,the formation mechanism of the special ground fissure has been discussed.
2007, 15(4): 453-457.
The situation and main characteristics of geological disaster due to a ground fissure are studied.The ground fissure is located between Pingquan Village and Wujiapo Village in Qingxu County.Founded since 2002,the hazards have become severer and severer and these seven villages have suffered from the ground fissure.By field investigating to the ground fissure,it is concluded that the distribution of the ground fissure is complex.It is found that the effect-zone width is various from 3 meters to 100 meters.Most buildings in the ground fissure zone were destroyed.In the zone,land deformations are shown as steep drop type and slow drop type,and the buildings within steep drop type zone were destroyed seriously.The destroy forms are shown as wall crack,ground surface tilt,foundation sink,stair fracture,window and door deformation,etc.The ground fissure is activating and will last for some time.It is suggested that the villagers in the zone move out as quickly as possible,and any engineering activity be restricted to avoid more loss.
The situation and main characteristics of geological disaster due to a ground fissure are studied.The ground fissure is located between Pingquan Village and Wujiapo Village in Qingxu County.Founded since 2002,the hazards have become severer and severer and these seven villages have suffered from the ground fissure.By field investigating to the ground fissure,it is concluded that the distribution of the ground fissure is complex.It is found that the effect-zone width is various from 3 meters to 100 meters.Most buildings in the ground fissure zone were destroyed.In the zone,land deformations are shown as steep drop type and slow drop type,and the buildings within steep drop type zone were destroyed seriously.The destroy forms are shown as wall crack,ground surface tilt,foundation sink,stair fracture,window and door deformation,etc.The ground fissure is activating and will last for some time.It is suggested that the villagers in the zone move out as quickly as possible,and any engineering activity be restricted to avoid more loss.
2007, 15(4): 458-462.
Huge hazards and economic losses are caused by the ground fissure in Shuanghuaishu Village,Sanyuan County,Shaanxi Province.The ground fissure is consist of two paralleled fissures over 4 km length.Some works of exploratory trench,exploratory well and tunnel are done on site of the fissures.Then the features of plane distribution,section structure,activity and mechanics of the fissures are described in the paper.The exploratory results reveal that the F1 fissure on the south side of Shuanghuaishu ground fissure has larger width of fracture zone and higher active level than the F2 fissure on the North side.There are over 50 m wide areas and over 30 cracks in the fracture zone of the F1 fissure,which is not common in the loess area.
Huge hazards and economic losses are caused by the ground fissure in Shuanghuaishu Village,Sanyuan County,Shaanxi Province.The ground fissure is consist of two paralleled fissures over 4 km length.Some works of exploratory trench,exploratory well and tunnel are done on site of the fissures.Then the features of plane distribution,section structure,activity and mechanics of the fissures are described in the paper.The exploratory results reveal that the F1 fissure on the south side of Shuanghuaishu ground fissure has larger width of fracture zone and higher active level than the F2 fissure on the North side.There are over 50 m wide areas and over 30 cracks in the fracture zone of the F1 fissure,which is not common in the loess area.
2007, 15(4): 463-468.
Ground fissures that are typical geo-hazards in Xian area may cause damage of various types of buildings,transportation facilities,city lifeline projects and the land resources,especially endangering the construction and running of Xian Subway Line 2.Ground fissures in Xian area were introduced firstly,then distribution and characteristics of ground fissures were summarized around Xian Subway Line 2.These fissures have been observed and their accumulative moving value were determined.The research results gave the moving speed of each ground fissures at different time stage,and determined the influence scale/area of each fissure.Finally,some suggestions and measures were proposed to prevent and control these ground fissures disasters.
Ground fissures that are typical geo-hazards in Xian area may cause damage of various types of buildings,transportation facilities,city lifeline projects and the land resources,especially endangering the construction and running of Xian Subway Line 2.Ground fissures in Xian area were introduced firstly,then distribution and characteristics of ground fissures were summarized around Xian Subway Line 2.These fissures have been observed and their accumulative moving value were determined.The research results gave the moving speed of each ground fissures at different time stage,and determined the influence scale/area of each fissure.Finally,some suggestions and measures were proposed to prevent and control these ground fissures disasters.
2007, 15(4): 469-474.
The maximum vertical displacement of ground fissure is an important parameter to the structural design of Xian Metro Line 2 going through ground fissures.Based on leveling monitoring data,the activity characteristics in different stage of each ground fissure along Xian metro Line 2 are analysed in this paper.The future activity trend of each ground fissure is predicted.Then through the contrast analysis of the maximum vertical displacements calculated by the annual activity rate of different historical stages,the maximum vertical displacement of crossing points in which ground fissures intersect with Xian Metro Line 2 are gotten.The ground fissures along Xian Metro Line 2 are classified into four categories,i.e.Ⅰ,Ⅱ,Ⅲ and Ⅳ according to the maximum vertical displacements of ground fissures.
The maximum vertical displacement of ground fissure is an important parameter to the structural design of Xian Metro Line 2 going through ground fissures.Based on leveling monitoring data,the activity characteristics in different stage of each ground fissure along Xian metro Line 2 are analysed in this paper.The future activity trend of each ground fissure is predicted.Then through the contrast analysis of the maximum vertical displacements calculated by the annual activity rate of different historical stages,the maximum vertical displacement of crossing points in which ground fissures intersect with Xian Metro Line 2 are gotten.The ground fissures along Xian Metro Line 2 are classified into four categories,i.e.Ⅰ,Ⅱ,Ⅲ and Ⅳ according to the maximum vertical displacements of ground fissures.
2007, 15(4): 475-482.
Collective effect of long-term structure deformation,unloading and earthquake can result in large-scale deformation and looseness of rock mass under the dynamic condition of regional stability.Large number of weak structural planes developed in relaxed rock mass.The rock mass is completely cracked,very relaxed,highly permeable.Much open-joint and ground fissure exist in the rock mass.The information of the rock breakage is very distinct under the paleo-earthquake.Deformation-relaxed types of relaxed rock mass may be divided simply into five models:i.e.unloading deform-relaxation,toppling deform-relaxation,bedding-slip relaxation,deform-relaxation controlled by faults and relaxation controlled by cranny /joint.The vibration test of dynamic models of rock mass indicates that the earthquake power is the main factor of relaxed effect of the rock mass.The result of numerical simulation shows that large-scale Instability and failure would not occur in the relaxed rock mass under self-weight stress,but it would occur under the earthquake power.
Collective effect of long-term structure deformation,unloading and earthquake can result in large-scale deformation and looseness of rock mass under the dynamic condition of regional stability.Large number of weak structural planes developed in relaxed rock mass.The rock mass is completely cracked,very relaxed,highly permeable.Much open-joint and ground fissure exist in the rock mass.The information of the rock breakage is very distinct under the paleo-earthquake.Deformation-relaxed types of relaxed rock mass may be divided simply into five models:i.e.unloading deform-relaxation,toppling deform-relaxation,bedding-slip relaxation,deform-relaxation controlled by faults and relaxation controlled by cranny /joint.The vibration test of dynamic models of rock mass indicates that the earthquake power is the main factor of relaxed effect of the rock mass.The result of numerical simulation shows that large-scale Instability and failure would not occur in the relaxed rock mass under self-weight stress,but it would occur under the earthquake power.
2007, 15(4): 483-489.
As an important hazardous geological phenomena,caves in loess area have caused loss and damages to various constructions.In particular,the loss and damage to highways are the most distinctive.Site investigation proves that caves in loess have led to different damages to road bed,slopes,bridges,tunnels and drainage facilities of highway.Such damage shows certain regularities in the types,positions and degrees.To understand the essential regularities and mechanisms of the damage caused by caves in loess and guide the stability evaluation and prevention of caves of highway in loess,the geological mode and mechanism of damage of caves in loess to road bed,slopes,bridges,tunnels and drainage facilities of highway are summarized on the basis of widespread site investigations on the highways in Shaanxi and Gansu provinces.
As an important hazardous geological phenomena,caves in loess area have caused loss and damages to various constructions.In particular,the loss and damage to highways are the most distinctive.Site investigation proves that caves in loess have led to different damages to road bed,slopes,bridges,tunnels and drainage facilities of highway.Such damage shows certain regularities in the types,positions and degrees.To understand the essential regularities and mechanisms of the damage caused by caves in loess and guide the stability evaluation and prevention of caves of highway in loess,the geological mode and mechanism of damage of caves in loess to road bed,slopes,bridges,tunnels and drainage facilities of highway are summarized on the basis of widespread site investigations on the highways in Shaanxi and Gansu provinces.
2007, 15(4): 490-494.
Based on the field survey and lab experiment,this paper analyses the forming factors of loess caves in west Shanxi.Research shows that the combined function of various external and internal factors is the main origins of loess caves in west Shanxi.The main factors include loess quanlity,loess microstruture,joint and fracture,loess layer thickness,hydro-geological and climate,topography and morphology conditions.The loess quality and microstructure is the interior factors of loess caves formation.The loess layer,joint and fracture present interspace and physical base for loess caves.The upland water and ground water are the motive power of loess caves formation.The topography and morphology conditions control the area distribution of loess caves.
Based on the field survey and lab experiment,this paper analyses the forming factors of loess caves in west Shanxi.Research shows that the combined function of various external and internal factors is the main origins of loess caves in west Shanxi.The main factors include loess quanlity,loess microstruture,joint and fracture,loess layer thickness,hydro-geological and climate,topography and morphology conditions.The loess quality and microstructure is the interior factors of loess caves formation.The loess layer,joint and fracture present interspace and physical base for loess caves.The upland water and ground water are the motive power of loess caves formation.The topography and morphology conditions control the area distribution of loess caves.
2007, 15(4): 495-499.
The basic characters of gravity water are generalized.,The authors suggest that the gravity water is one of the key factors of the hazards such as loess slope slides,ground fissures and loess tunnels.Through example study such as loess tunnel hazard,the modes of surface runoff are generalized as four basic modes:gravity water evenly infiltration mode,surface runoff injection mode,gravity water injection through dominant path mode and multiple mode.
The basic characters of gravity water are generalized.,The authors suggest that the gravity water is one of the key factors of the hazards such as loess slope slides,ground fissures and loess tunnels.Through example study such as loess tunnel hazard,the modes of surface runoff are generalized as four basic modes:gravity water evenly infiltration mode,surface runoff injection mode,gravity water injection through dominant path mode and multiple mode.
2007, 15(4): 500-505.
According to the field investigation of many landslides in loess area,the loess landslide,strewed by moving modes,can be cognized to four typical types:collapse landslide,high-speed distant landslide,low-speed creep landslide and landslide mudflow.Take four typical loess landslides for example,the forming conditions and the kinematics characters of all manner of landslide are analyzed respectively.Space forecasting index,affect causation and modeling idea have been built responding to four kinds relatively under their moving modes.It provides a main thinking way of space forecasting of landslide disaster in loess land and it is also the base of forecasting academic modeling of landslide.
According to the field investigation of many landslides in loess area,the loess landslide,strewed by moving modes,can be cognized to four typical types:collapse landslide,high-speed distant landslide,low-speed creep landslide and landslide mudflow.Take four typical loess landslides for example,the forming conditions and the kinematics characters of all manner of landslide are analyzed respectively.Space forecasting index,affect causation and modeling idea have been built responding to four kinds relatively under their moving modes.It provides a main thinking way of space forecasting of landslide disaster in loess land and it is also the base of forecasting academic modeling of landslide.
2007, 15(4): 506-512.
Based on the study of loess collapsible mechanism,the interactions of the loess collapsibility and physical properties in Eastern Gansu Province,P.R.China are analyzed.The correlation equation between collapsible coefficient and water content,porosity,plasticity index(clay content)is developed with multifactor regression.The results show that collapsible coefficient correlated physical index better and the collapsible amounts calculated by the correlation equation are near to the test amount.It rightly reflects collapsible law changed with depth.This equation has a good value in engineering to estimate collapsible loess site.
Based on the study of loess collapsible mechanism,the interactions of the loess collapsibility and physical properties in Eastern Gansu Province,P.R.China are analyzed.The correlation equation between collapsible coefficient and water content,porosity,plasticity index(clay content)is developed with multifactor regression.The results show that collapsible coefficient correlated physical index better and the collapsible amounts calculated by the correlation equation are near to the test amount.It rightly reflects collapsible law changed with depth.This equation has a good value in engineering to estimate collapsible loess site.
2007, 15(4): 513-520.
Collapsible loess research of the expressway engineering is basically to adopt the criterion and experiment rules of buildings to investigate and design,due to the working circumstance and mechanics condition different to buildings foundation widely.Applying criterion and experiment rules of buildings directly to collapsibility evaluation and calculation of loess expressway is blindness and inconsequence.The more important is the lack of pertinence.Through the practicability and rationality research on the present criterion to subgrade loess collapsibility,combined the rainfall infiltration depth distributing law,the paper brings forward loess collapsibility evaluation method and model which suitable for expressway subgrade in loess area.
Collapsible loess research of the expressway engineering is basically to adopt the criterion and experiment rules of buildings to investigate and design,due to the working circumstance and mechanics condition different to buildings foundation widely.Applying criterion and experiment rules of buildings directly to collapsibility evaluation and calculation of loess expressway is blindness and inconsequence.The more important is the lack of pertinence.Through the practicability and rationality research on the present criterion to subgrade loess collapsibility,combined the rainfall infiltration depth distributing law,the paper brings forward loess collapsibility evaluation method and model which suitable for expressway subgrade in loess area.
2007, 15(4): 521-526.
In the collapsible loess area,it cant meet the need of strength and deformation characteristic while loess as the main raw material of expressway subgrade.There are three effective and applied treatment methods:vibrating roller compaction,rolling dynamic compaction,and dynamic compaction.According to data from test in situ and indoor test,going along finite element simulation,it concludes that foundation deformation decreases along with the increase treatment energy,embankment self deformation keeps steady.To the treatment depth and deformation minishing effect,the best is the dynamic compaction.The rolling dynamic compaction takes second place.The last is the vibrating roller compaction.Quadratic polynomial regression is used to analyze the correlations between the settlement and deformation of foundation surface center and different road embankment heights.The vibrating roller compaction treatment technology benefits for embankment height 2~4meters.The rolling dynamic compaction treatment technology suits for embankment height 5~10 meters.The height over 10 meters usually be treated with the dynamic compaction or directly make use of bridge to instead of.It is significant to expressway subgrade construction and safeguard in loess area.
In the collapsible loess area,it cant meet the need of strength and deformation characteristic while loess as the main raw material of expressway subgrade.There are three effective and applied treatment methods:vibrating roller compaction,rolling dynamic compaction,and dynamic compaction.According to data from test in situ and indoor test,going along finite element simulation,it concludes that foundation deformation decreases along with the increase treatment energy,embankment self deformation keeps steady.To the treatment depth and deformation minishing effect,the best is the dynamic compaction.The rolling dynamic compaction takes second place.The last is the vibrating roller compaction.Quadratic polynomial regression is used to analyze the correlations between the settlement and deformation of foundation surface center and different road embankment heights.The vibrating roller compaction treatment technology benefits for embankment height 2~4meters.The rolling dynamic compaction treatment technology suits for embankment height 5~10 meters.The height over 10 meters usually be treated with the dynamic compaction or directly make use of bridge to instead of.It is significant to expressway subgrade construction and safeguard in loess area.
2007, 15(4): 527-533.
Based on the filed-tests of rainfall erosion to the four kinds of highway-slopes:slope without protection,grass sowing in thick nourishment,grass sowing in three dimensional network and platform tree-planting,this paper expounds the effects of rainfall on different kinds of highway-slopes in the following aspects:hillslope-runoff,mud content and slope erosion.From the tests,two conclusions can be drawn.One is that the process of rainfall erosion to highway-slopes can be described as follows:the raindrop first clashes the soil,and then the clod is dispersed and finally the slope is eroded.The other is that the most serious erosion to slope is due to the water from platform upside.In the end,the paper demonstrates that the effective ways to reduce the rainfall erosion to slopes are plant protection such as grass sowing in three dimensional network and in thick nourishment or platform planting.It also provides a reliable basis for the design of plant protection to highway-slopes in loess areas.
Based on the filed-tests of rainfall erosion to the four kinds of highway-slopes:slope without protection,grass sowing in thick nourishment,grass sowing in three dimensional network and platform tree-planting,this paper expounds the effects of rainfall on different kinds of highway-slopes in the following aspects:hillslope-runoff,mud content and slope erosion.From the tests,two conclusions can be drawn.One is that the process of rainfall erosion to highway-slopes can be described as follows:the raindrop first clashes the soil,and then the clod is dispersed and finally the slope is eroded.The other is that the most serious erosion to slope is due to the water from platform upside.In the end,the paper demonstrates that the effective ways to reduce the rainfall erosion to slopes are plant protection such as grass sowing in three dimensional network and in thick nourishment or platform planting.It also provides a reliable basis for the design of plant protection to highway-slopes in loess areas.
2007, 15(4): 534-538.
Dynamic constitutive model of soils and contact model of soil structure are analyzed in detail,non-linear equivalent viscoelastic model and Ramber-Osgood model are employed to study the dynamic interaction of soils and subway tunnel.The analysis results also indicate that the materials used in the models should not only satisfy the similarity theory in the model test,but also refer to the above selected models in the design of boundary conditions and earthquake input.The dynamic response of circle tunnel induced by earthquake wave is analyzed,and the results show that the maximum of the dynamic-load stress is located on the keystone,which results in cracks at the top of tunnel.And the influence of porosity on the lateral deformation of structure is also analyzed.The theory analysis of this case study is validated by the fact of this engineering.Thus,the results presented in this paper referes for the earthquake-resistance designing of this subway tunnel.
Dynamic constitutive model of soils and contact model of soil structure are analyzed in detail,non-linear equivalent viscoelastic model and Ramber-Osgood model are employed to study the dynamic interaction of soils and subway tunnel.The analysis results also indicate that the materials used in the models should not only satisfy the similarity theory in the model test,but also refer to the above selected models in the design of boundary conditions and earthquake input.The dynamic response of circle tunnel induced by earthquake wave is analyzed,and the results show that the maximum of the dynamic-load stress is located on the keystone,which results in cracks at the top of tunnel.And the influence of porosity on the lateral deformation of structure is also analyzed.The theory analysis of this case study is validated by the fact of this engineering.Thus,the results presented in this paper referes for the earthquake-resistance designing of this subway tunnel.
2007, 15(4): 545-548.
A quite number of triaxial creep tests were conducted on mica-quartzose schist,and the characteristics of creep deformation and long-term strength for this schist was analyzed by comparing with radial creep and axial creep in the tests.It was shown that,for this schist,taking the long-term strength of radial creep as the long-term strength was more reasonable since the radial creep is more sensitive than the axial creep.Besides,the higher confining compression is,the stronger the restraint of compression was to radial deformation,which resulted in decrease of both the long-term strength of radial creep and the long-term strength of axial creep.However,the ratio of the long-term strength of radial creep to the long-term strength of axial creep reduces with increasing of confining compression.This case study also indicated that the study of radial creep is significant.
A quite number of triaxial creep tests were conducted on mica-quartzose schist,and the characteristics of creep deformation and long-term strength for this schist was analyzed by comparing with radial creep and axial creep in the tests.It was shown that,for this schist,taking the long-term strength of radial creep as the long-term strength was more reasonable since the radial creep is more sensitive than the axial creep.Besides,the higher confining compression is,the stronger the restraint of compression was to radial deformation,which resulted in decrease of both the long-term strength of radial creep and the long-term strength of axial creep.However,the ratio of the long-term strength of radial creep to the long-term strength of axial creep reduces with increasing of confining compression.This case study also indicated that the study of radial creep is significant.
2007, 15(4): 549-554.
On the basis of the investigations to the neotectonic movement of Tianshui area,Manifestations of various neotectonic movements are studied in detail firstly.Secondly,according to the manifestations of various neotectonic movements,the neotectonic movement features of each zone are studied.The result shows that the neotectonic movement of Tianshui area has such features:the relative vertical motion is obvious,the rate of relative vertical motion is unequal,the neotectonic movement intensity is unequal on the space,the fault activity is strong,and the earthquake is frequent.At last,the neotectonic movement to evolution process is analyzed in brief.The level process is considered on Tianshui area.
On the basis of the investigations to the neotectonic movement of Tianshui area,Manifestations of various neotectonic movements are studied in detail firstly.Secondly,according to the manifestations of various neotectonic movements,the neotectonic movement features of each zone are studied.The result shows that the neotectonic movement of Tianshui area has such features:the relative vertical motion is obvious,the rate of relative vertical motion is unequal,the neotectonic movement intensity is unequal on the space,the fault activity is strong,and the earthquake is frequent.At last,the neotectonic movement to evolution process is analyzed in brief.The level process is considered on Tianshui area.
2007, 15(4): 555-558.
This article is based on the basic characters and deformation styles etc of the loose fill slope with great height.It takes the way of gene sensitive analysis to calculate and discuss effect degree for the major factors to the stability of the high slope.The factors include geometric features of the slope,daily blasting vibration and water.They are used to determine the geometric features of the slope as the key factor to its stability.Then It puts forward the proper angle,height and the reserved width,artificial deposits parameters and the maximum deposit height of the slope under the condition of the stable dump slope.
This article is based on the basic characters and deformation styles etc of the loose fill slope with great height.It takes the way of gene sensitive analysis to calculate and discuss effect degree for the major factors to the stability of the high slope.The factors include geometric features of the slope,daily blasting vibration and water.They are used to determine the geometric features of the slope as the key factor to its stability.Then It puts forward the proper angle,height and the reserved width,artificial deposits parameters and the maximum deposit height of the slope under the condition of the stable dump slope.
2007, 15(4): 559-563.
Shaanxi is one of the provinces where soft metamorphic rock has distributed widely.In recent years,with engineering construction increasing or enlarging,slope hazards have been frequently happening,and the loss has also been increasing year by year.According to the geological survey on No.316 national road from Zaoyang to Shuhe in the southern Shaanxi province,five deformation and failure patterns of the slope in soft metamorphic rock are concluded and analyzed in detail,for effective forecast and economical treatment of slope hazard.
Shaanxi is one of the provinces where soft metamorphic rock has distributed widely.In recent years,with engineering construction increasing or enlarging,slope hazards have been frequently happening,and the loss has also been increasing year by year.According to the geological survey on No.316 national road from Zaoyang to Shuhe in the southern Shaanxi province,five deformation and failure patterns of the slope in soft metamorphic rock are concluded and analyzed in detail,for effective forecast and economical treatment of slope hazard.
2007, 15(4): 564-568.
The authors in this paper,according to the system analysis of stratum,constitution and landform,through studying the formation,the development and the characteristics of landslide,put forward the conception of pre-estimating landslide firstly based on the geologic structure cybernetics.The pre-estimating system for landslide is a technical method,which can determine the space position and the type of landslide,and can pre-estimating its developmental condition in the future without any exploration means,but according to all kinds of geological pre-estimating methods and topographical features of landslide.The authors build the basic system,the discriminating method and the working procedure of this technical method.They have applied this method to investigating the geological disasters along highways in Southern Shaanxi.This method has noboth theoretical and practical meaning.
The authors in this paper,according to the system analysis of stratum,constitution and landform,through studying the formation,the development and the characteristics of landslide,put forward the conception of pre-estimating landslide firstly based on the geologic structure cybernetics.The pre-estimating system for landslide is a technical method,which can determine the space position and the type of landslide,and can pre-estimating its developmental condition in the future without any exploration means,but according to all kinds of geological pre-estimating methods and topographical features of landslide.The authors build the basic system,the discriminating method and the working procedure of this technical method.They have applied this method to investigating the geological disasters along highways in Southern Shaanxi.This method has noboth theoretical and practical meaning.
2007, 15(4): 569-574.
This paper presents and compares some new techniques for source boundaries detection using potential-field data.The geologic boundaries of paleo-fault zone and faults in Shanxi Province with better resolution are recognized by the following methods:tilt derivative(TDR),total horizontal gradient of the TDR and theta map,etc..The results indicated that the new detection technology is more effective and accurate than the traditional horizontal gradient one and can gather more geological information.
This paper presents and compares some new techniques for source boundaries detection using potential-field data.The geologic boundaries of paleo-fault zone and faults in Shanxi Province with better resolution are recognized by the following methods:tilt derivative(TDR),total horizontal gradient of the TDR and theta map,etc..The results indicated that the new detection technology is more effective and accurate than the traditional horizontal gradient one and can gather more geological information.