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There are rich resources in Central and South America, and mining products export plays an important role in the regional economic development. In this paper, the mining products trade information of more than ten years in Central and South America is collected, and then the authors point out that a "diversified export" strategy has been implemented by Central and South America in recent years for reducing the dependence on the economy of the United States, and the export of Central and South America is continuously rising to China but declining to the United States because they are benefited from the great demands of China's development on resources. However, along with the development of the industrialization in the countries of Central and South America, increasingly more resources will be consumed in this region. Therefore, some Central and South American countries will reduce their energy and mining products exports in the future in the condition of meeting their own needs.

Copper consumption is the largest and the most important metal mineral resources during the process of industrialization, urbanization. This paper analyzes the reserves distribution of the global copper resources, global copper resource investment and development zone, and global mining copper demand increment and its capacity increment trend, showing that, (1) over the next 20 years the global iron and aluminum resource supply relatively loose, copper resources supply pressure is bigger; (2) Global copper resources are relatively scarce, the distribution, Chile, Peru and Australia among the three countries accounted for 53% of global reserves; (3) Along with the growth of the asean and India resource requirements, Africa, southeast Asia and central Asia will become the important resource of supply. (4) Since the 20th century, along with the global demand for resources at the center of transfer to North America, Asia Pacific (Europe), Europe, North America, South America, Australia and southeast Asia, in turn, become the important resource of supply

Over the next 20 years a rapid rise will be happen in global demand for steel, copper and aluminum, China will be the first biggest resource requirements country. This paper analyzes the global demand of steel, copper and aluminum, showing that global resource consumption center transfer according to the industrial centers, at present, China is the world's resources consumption center, steel, copper and aluminium consumption accounted for more than 40% of the world. Global demand for steel, copper and aluminum over the next 20 years will be rapid growth, accumulative total demand is 2 times of the past 20 years, but there may be a temporary slowdown in 3 - 5 years period. Over the next 20 years the first big country, China is one of the resource requirements of asean and India will become the main driver of demand growth.

In order to analysis in the next 20 years, how many copper resources China has, when the peak demand peak comes, how great is the supply gap, and how to deal with that situation, this paper uses the authority of statistical data and material from the international copper research group, the world bureau of metal, growth and development center, the United States geological survey, China's national bureau of statistics, China nonferrous metals industry association, and in the system analysis of China's future economic and social development trend, to analyze the Chinese copper resources future demand, supply tendency, which has been clear about the China's future copper resources supply the challenge.

In the next 20 years, how many copper resources China has, when the peak demand peak comes, how great is the supply gap, and how to deal with that situation? Scientific answer these questions is important premise to reasonably establish the national copper resources supply strategy, and guarantee the safety of Chinese copper resources. The next 20 years, even by low growth situation, China's copper demand will also be more than half of total of 20 century global copper consumption, the domestic copper resources supply capacity cannot satisfy the demand, external dependence will be maintained for a long time in 70% or so, which should be paid attention to, scientific deployed, and dealt with.

In this paper, firstly we utilize the elastic model, which provides the simplest representation of material behavior in civil engineering. This model is valid for homogeneous, isotropic, continuous materials that exhibit linear stress-strain behavior with no hysteresis on unloading. The elastic models include both isotropic and anisotropic elastic models. Then the Mohr-Coulomb model is used which can represent shear failure in soils and rocks in civil engineering and geotechnical engineering. After that, the strain- softening model is founded, which allows representation of nonlinear material softening and hardening behavior based on prescribed variations of the Mohr-Coulomb model properties (cohesion, friction, dilation, tensile strength) as functions of the deviatoric plastic strain. Finally, a case study is done for the stratified rock mass, the elastic modulus of the rock sample for different surrounding compressive are obtained, to exhibit the anisotropy characteristic of this type of rock material

Slope stability analysis is an important content in geotechnical engineering designing. And the safety factor is still the main index to evaluate the safety status of the whole slope, but the stability of each element of rock mass can not be reflected by the whole safety factor. Some scholars introduce the concept of point safety factor (PSF) to evaluate the stability of each element in rock-soil mass. However, the present work about PSF is remaining in the field of linear model, instead of nonlinear model. But in real situation, the nonlinear failure criterions are more adaptable used to describe the characteristic of rock mass, such as nonlinear failure characteristic of rock strength, structural characteristic and the effect of the stress to the strength of rock mass. So in this paper, the PSF based on the Hoek-Brown nonlinear mechanics model is founded, followed by calculation PSF for one rock mass element stability.

Stratified rock mass has been widely existing in geotechnical engineering. With obvious transversely isotropic characteristic, stability of stratified rock mass is not only related to strength of intact rock but also to the inclination and characteristic of structure plane. The parameters of the structure plane have great impact on the stability of stratified rock mass. For the stratified rock mass is no homogenous, the homogenous model is not suitable to describe the characteristic of stratified rock mass. Then building an appropriate becomes necessary. In the present paper, Ubiquitous-joint model is introduced to describe the characteristic of rock mass, and the strength reduction method based on the Ubiquitous-joint model is proposed, which then is used to calculate the safety factor of slope, while the relationships between safety factor, strength properties of structure plane are analyzed, whose results can give guidance for the real practice.

To study the grouting reinforcement mechanism in jointed rock slope, first, the theoretical deduction was done to calculate the critical length of slipping if the slope angle is larger than that of joint inclination; Second, the numerical calculation model was founded by FLAC3D, so as to find the stress and deformation responses of rock mass in the state before and after grouting. the analysis results show that the range between the boundary of critical slipping block and the joint plane that passes the slope toe is the effective grouting area (EGA). After excavation, large deformation occurs along the joint plane. After grouting, the displacements of rock particles become uniform and continuous, and large deformations along the joint plane are controlled; the dynamic displacement can reflect the deformation response of slope during excavation in the state before and after grouting, as well as the shear location of potential slip plane. After grouting, the dynamic displacement of each monitoring point reaches the peak value with very few time steps, which indicate that the parameters of the joint plane, such as strength and stiffness, are improved; the stress field becomes uniform. Tensile area reduces gradually; whole stability of the slope and its ability to resist tensile and shear stress are improved greatly.

A stratified rock mass model was founded by FLAC (superscript 3D). The failure mode and anisotropic characteristic of strength for stratified rock mass were analyzed. The analysis results show that the numerical simulation can visually reflect the failure modes of rock samples under different inclination angles β of structural plane. The stiffness of rock sample before peak strength changes in the compressive procedure. With the increase of β, the compressive strength o of rock sample decreases firstly and then increases; when β is in the range of 20°-30° and 80°-90°, ac has the largest sensitivity to β; while β falls in the range of 30°-70°, ac varies little. When O(subscript j)＜β＜90° (O(subscript j) is friction angle of structure plane), the results obtained from numerical simulation and theoretical analysis are in almost the same values; whileβ≤O(subscript j) or β=90°, they are in great different values. The results obtained from theoretical analysis are obvious larger than those from numerical simulation; and the results from numerical simulation can reflect the difference of compressive strength of rock samples for the two situations ofβ≥O(subscript j) and β=90°, which is in more accordance with the real situation.

In view of fuzziness of university teaching quality evaluation, AHP-based multi-level fuzzy comprehensive evaluation model become the advantage model for university teaching quality assessment. It is of great importance to evaluate scientifically teachers' teaching quality in the classroom. The methods of AHP and Fuzzy comprehensive evaluation are applied to evaluation of classroom teaching quality. By analyzing constituent elements of teaching quality, proposed that the index system should be on the basis of teaching attitude, teaching level, teaching content and teaching effectiveness, index weights should be determined by using of AHP, the model should be established by using of Fuzzy comprehensive evaluation, which turns out that the evaluation results can reflect the management of teaching quality more objectively, so as to provide a new way for evaluation of teaching quality, thus it has theoretical and practical value. A practical mathematical model for the teaching quality evaluation is established under the fuzzy circumstances. A example is included.

The interaction between the rock slope and tunnel is very important in geotechnical engineering for they will affect each other. In some cases, tunnel is first excavated long time ago, then with the time passed on, the stress in the rock mass reaches its equilibrium state, and the deformation of the rock mass becomes unchanged. In the following, the surface rock mass is excavated to form a slope, but due to the excavation of the tunnel had disturbed the stress and deformation of rock mass, the slope stability and excavation response will be different from the cases where there does not exist the tunnel excavation in the rock mass. So the interaction between the slope and tunnel need to be considered. In the past, the simplified engineering method is chosen to solve these problems. Recently, due to the rapid advances in computer technology and sustained development, the numerical modeling method has been pushed to the forefront of geotechnical practice, which explores a new way for geotechnical designing. So in the present paper, one slope of rock mass with tunnel in it is chosen as the engineering background, the numerical model is built to realize the modeling for the interaction between the slope and tunnel; two situations are set to study the differences of stress and deformation characteristic between the slope in rock mass with tunnel and without tunnel, whose results can give some guidance for the real practice.

Stratified rock mass has been widely existing in geotechnical engineering, especially in tunnel engineering. When tunnel excavated in stratified rock mass, the stress and deformation characteristic of the surrounding rock mass are very different from that in the normal rock mass. In order to study the stress and deformation response tunnel excavation, numerical model is built by the commercial package ANASYS, then the model is transferred based on the self-compiled program to the to the FLAC3D for calculation, then the excavation of tunnel is simulated to find out the effect of the excavation disturbance on the tunnel surrounding rock mass. During simulation procedure, different insitu-stress is set to the model to obtain effect of different horizontal stress on the calculation results, such as the unbalance force of the tunnel surrounding rock mass, the maximum displacement of the tunnel, the horizontal displacement contour and the vertical displacement contour. The calculation result can give some guidance for the real practice.

In order to study the three dimensional stability of one large underground stope after excavation, the numerical simulation software FLAC3D is used to calculate the deformation and failure situation of the surrounding rock mass. The calculations are done for two cases of whether penetration taking place in the goaf. During calculation the effects of penetration of excavation areas to the stability of stope are analyzed. The results can give some guidance for the real practice.

Simplified mechanical model can not reflect the real situation of the interaction between foundation and cables. Then numerical software FLAC3D is used to simulate the procedure of foundation excavation and cable reinforcement. Deformation responses of foundation are analyzed as well as the mechanical response of cables. The results show that, (1) the procedure of excavation leads to the deformation of soil mass in foundation, which is the reasons of tensile failure and shear failure; for tensile failure areas, the length of soil nailing should be set surpass the slip plane; for shear failure areas, the density of cables should be set larger at the place of shear opening. (2) after excavation, the axial stress distributes different along the cable shaft, location of maximum axial stress along cable can indicate the location of potential slip plane. FLAC3D can simulate the excavation and reinforcement of foundation reasonably, whose result can give guidance for design and construction.