针对岩体结构面发育特征的不确定性,提出一种岩质边坡异形滑动面搜索方法 .以Ⅲ,Ⅳ结构面岩体为研究对象,结合GeoSMA-3D(geotechnical structure and model analysis-3D)程序中块体切割和关键块体判别模块,将滑坡体设定为几何多面体.岩...针对岩体结构面发育特征的不确定性,提出一种岩质边坡异形滑动面搜索方法 .以Ⅲ,Ⅳ结构面岩体为研究对象,结合GeoSMA-3D(geotechnical structure and model analysis-3D)程序中块体切割和关键块体判别模块,将滑坡体设定为几何多面体.岩体的内部块体组合形成多面体,以多面体的表面表征滑动面.引入层次分析法,建立滑动面准定量化评价准则.以小盘岭边坡为例,将异形滑动面判定准则导入GeoSMA-3D程序中,研究表明边坡存在6个关键块体,组合滑动面有3个,潜在滑动面安全系数为1.046,滑动面几何形态与实际边坡拟合度高达95%,验证了岩质边坡滑动面搜索方法的合理性.展开更多
Complicated geological structures make it difficult to analyze the stability of rock slopes, such as faults, weak intercalated layers or joint fissures. Based on 3D geological modeling and surface block identifying me...Complicated geological structures make it difficult to analyze the stability of rock slopes, such as faults, weak intercalated layers or joint fissures. Based on 3D geological modeling and surface block identifying methods, an integrated methodology framework was proposed and realized to analyze the stability of surface blocks in rock slopes. The surface blocks cut by geological structures, fissures or free faces could be identified subjected to the four principles of closure, completeness, uniqueness and validity. The factor of safety(FOS)of single key block was calculated by the limit equilibrium method. If there were two or more connected blocks, they were defined as a block-group. The FOS of a block-group was computed by the Sarma method. The proposed approach was applied to an actual rock slope of a hydropower project, and some possible instable blocks were demonstrated and analyzed visually. The obtained results on the key blocks or block-groups provide essential information for determining potential instable region of rock slopes and designing effective support scheme in advance.展开更多
The weak structure plane is an important factor affecting the stability of rock slope, and detecting the spatial structure of the weak structural plane is beneficial to analyze the stability of the slope and estimate ...The weak structure plane is an important factor affecting the stability of rock slope, and detecting the spatial structure of the weak structural plane is beneficial to analyze the stability of the slope and estimate the quantity of the landslide. Based on 3D electrical resistivity tomography, a model of rock slope with weak structure plane is established, and the characteristics of three-dimensional resistivity imaging of weak structure plane under different ground water conditions are simulated. The results show that the weak structural plane has a better reflection in 3D electrical resistivity tomography;the distribution of weak structural plane of 3D resistivity imaging can be roughly determined under different ground water conditions;the three-dimensional electrical resistivity tomography is feasible in the detection of weak structural plane of rock slope.展开更多
The appearance of 3D laser scanning technology is one of the most important technology revolutions in surveying and mapping field. It can be widely used in many interrelated fields, such as engineering constructions a...The appearance of 3D laser scanning technology is one of the most important technology revolutions in surveying and mapping field. It can be widely used in many interrelated fields, such as engineering constructions and 3D measurements, owing to its prominent characteristics of the high efficiency and high precision. At present its application is still in the initial state, and it is quite rarely used in China, especially in geotechnical engineering and geological engineering fields. Starting with a general introduction of 3D laser scanning technology, this article studies how to apply the technology to high rock slope investigations. By way of a case study, principles and methods of quick slope documentation and occurrence measurement of discontinuities are discussed and analyzed. Analysis results show that the application of 3D laser scanning technology to geotechnical and geological engineering has a great prospect and value.展开更多
The effects of nonlinearity of strength envelopes on 3D slope stability analysis are investigated.A power relation for the nonlinear envelope is employed to derive the 3D factor of safety equations of an extended Spen...The effects of nonlinearity of strength envelopes on 3D slope stability analysis are investigated.A power relation for the nonlinear envelope is employed to derive the 3D factor of safety equations of an extended Spencer method hich satisfies boty force equilibrium and moment equilibrium.Then,a search procedure is presented based on dynamic programming to determine the 3D critical slip surface for a general slope,Linear and nonlinear strength envelopes used for slope stability computations are obtained by fitting curves to the 103 strength data of consolidated-undrained(CU)triaxial compression tests for compacted Israeli clay.Results of a typical 3D problem show that a linear approximation of the nonlinear strength envelope may lead to a significant overestimation of calculated safety factors.展开更多
文摘针对岩体结构面发育特征的不确定性,提出一种岩质边坡异形滑动面搜索方法 .以Ⅲ,Ⅳ结构面岩体为研究对象,结合GeoSMA-3D(geotechnical structure and model analysis-3D)程序中块体切割和关键块体判别模块,将滑坡体设定为几何多面体.岩体的内部块体组合形成多面体,以多面体的表面表征滑动面.引入层次分析法,建立滑动面准定量化评价准则.以小盘岭边坡为例,将异形滑动面判定准则导入GeoSMA-3D程序中,研究表明边坡存在6个关键块体,组合滑动面有3个,潜在滑动面安全系数为1.046,滑动面几何形态与实际边坡拟合度高达95%,验证了岩质边坡滑动面搜索方法的合理性.
基金Supported by the National Natural Science Foundation of China(No.51379006 and No.51321065)the Program for New Century Excellent Talents in University of Ministry of Education of China(NCET-12-0404)
文摘Complicated geological structures make it difficult to analyze the stability of rock slopes, such as faults, weak intercalated layers or joint fissures. Based on 3D geological modeling and surface block identifying methods, an integrated methodology framework was proposed and realized to analyze the stability of surface blocks in rock slopes. The surface blocks cut by geological structures, fissures or free faces could be identified subjected to the four principles of closure, completeness, uniqueness and validity. The factor of safety(FOS)of single key block was calculated by the limit equilibrium method. If there were two or more connected blocks, they were defined as a block-group. The FOS of a block-group was computed by the Sarma method. The proposed approach was applied to an actual rock slope of a hydropower project, and some possible instable blocks were demonstrated and analyzed visually. The obtained results on the key blocks or block-groups provide essential information for determining potential instable region of rock slopes and designing effective support scheme in advance.
文摘The weak structure plane is an important factor affecting the stability of rock slope, and detecting the spatial structure of the weak structural plane is beneficial to analyze the stability of the slope and estimate the quantity of the landslide. Based on 3D electrical resistivity tomography, a model of rock slope with weak structure plane is established, and the characteristics of three-dimensional resistivity imaging of weak structure plane under different ground water conditions are simulated. The results show that the weak structural plane has a better reflection in 3D electrical resistivity tomography;the distribution of weak structural plane of 3D resistivity imaging can be roughly determined under different ground water conditions;the three-dimensional electrical resistivity tomography is feasible in the detection of weak structural plane of rock slope.
基金the Key Project of Joint Funds of Yalongjiang River Development of the National Natural Science Foundation of China (No. 50539050)
文摘The appearance of 3D laser scanning technology is one of the most important technology revolutions in surveying and mapping field. It can be widely used in many interrelated fields, such as engineering constructions and 3D measurements, owing to its prominent characteristics of the high efficiency and high precision. At present its application is still in the initial state, and it is quite rarely used in China, especially in geotechnical engineering and geological engineering fields. Starting with a general introduction of 3D laser scanning technology, this article studies how to apply the technology to high rock slope investigations. By way of a case study, principles and methods of quick slope documentation and occurrence measurement of discontinuities are discussed and analyzed. Analysis results show that the application of 3D laser scanning technology to geotechnical and geological engineering has a great prospect and value.
文摘The effects of nonlinearity of strength envelopes on 3D slope stability analysis are investigated.A power relation for the nonlinear envelope is employed to derive the 3D factor of safety equations of an extended Spencer method hich satisfies boty force equilibrium and moment equilibrium.Then,a search procedure is presented based on dynamic programming to determine the 3D critical slip surface for a general slope,Linear and nonlinear strength envelopes used for slope stability computations are obtained by fitting curves to the 103 strength data of consolidated-undrained(CU)triaxial compression tests for compacted Israeli clay.Results of a typical 3D problem show that a linear approximation of the nonlinear strength envelope may lead to a significant overestimation of calculated safety factors.
