The necessary concept of stability analysis of largespan steel structure is reviewed. From a design point of view,the characteristics of all types of instability are interpreted.

Thermal-thaw sliding collapse is a typical example. The following researches have been carried out in this paper, including slope instability patterns analysis in permafrost region of Qinghai-Tibet Platean, geological structure analysis for typical permafrost slope, model experiment of thermal-thaw sliding collapse of Qinghai-Tibet milestone K3035, stability analysis method, in-situ monitoring and numerical simulation of temperature field, displacement field.

First introduces the instability type of portal frames and educe the curt formula under each instability conditions with traditional computing methods.

Joint stiffness is one of the key factors influence on structural limited capacity, and is considered differently according to the structure system and instability type.

It is given the correct determining curve of instability type for broken rock blocks of main roof, and the errors on the determining curves in foretime literature is rectified.

Applying the linear airfoil theory and treating the air flow as two-dimensional ideal potential flow, the characteristic equation of membrane vibration is deduced by simulating membrane figure with traveling wave. Then instability type and phase of membrane is investigated.

The paper discusses the stability factors, the instability types and the stability estimating method of slope in cold region, and discusses that the freezing-thawing circulation has effect on rock slope and soil slope.

The load-deflection curve of pole under wind load is solved based on the non-linear analysis. Then the ultimate capacity of the pole and the type of the instability are determined.

The paper analyses sidewall stress state and sidewall unstable type,and combines with log data and indoor experimental result of core. Through analysis and calculation,the method of calculating slough formation pressure is proposed. By application of the method in 3 wells in Yancheng area,result shows that slough pressure section fits in with field practical condition.

Radiology of trauma to the wrist: Dislocations, fracture dislocations, and instability patterns

Finally, the various posttraumatic instability patterns of the wrist are discussed.

This review addresses the pathoanatomical basics as well as the clinical and radiological presentation of instability patterns of the wrist.

Climatic Variations In The Moisture and Instability Patterns Of The Atmospheric Boundary Layer On The East Mediterranean Coastal

The governing equation is formulated as a fourth-order eigenvalue problem with non-constant coefficients and then a complex WKB technique is employed to yield the localised instability patterns.

It is shown that the number of regimes which lose stability, the instability type, the number of convective rollers developed, and the heat transfer depend significantly on the vessel geometry.

Results: Alterations of microsatellite were classified into microsatellite instability type I, type II and loss of heterozygosity (LOH).

Different types of instability differ clearly in their precursors, and the instability type is closely related with the geometrical texture and the deformation stage of the fault system.

The last makes it possible to study the physical instability correctly and, in particular, to determine the instability type.

In the present article, an attempt is undertaken to account for the production of shear instability type structures and structures that arise as the beam dimensions in the feedback loop are varied.

Discussed in this article are mainly elementory rules and influence factors of the unstable hillslopc in the south mountain land of Anhui Province. The unstable classification system for the hillslope of the rock mass and the whole instable process has been divided into distinct progressive steps. Because the change of the stability has taken, place under the influence of various factors, a new engineering geological analysis method of the unstable hillslop is suggested, At the end of this paper.

The experimental researches on creep-failure of quartzite and granite, taking place at the middle-lower crustal conditions, show that semi-brittle creep-failure of crustal rocks, resulted either from fracture or from flow, could be of sudden or gradual instability modes. The transition of failure-instability modes of crustal rocks is strongly temperature, pressure and plastic component-dependent, which makes the semi-brittle failure of rocks much more complex.To identify such a complex deformation-failure process,...

The experimental researches on creep-failure of quartzite and granite, taking place at the middle-lower crustal conditions, show that semi-brittle creep-failure of crustal rocks, resulted either from fracture or from flow, could be of sudden or gradual instability modes. The transition of failure-instability modes of crustal rocks is strongly temperature, pressure and plastic component-dependent, which makes the semi-brittle failure of rocks much more complex.To identify such a complex deformation-failure process, it is the first thing to distinguish fracture, friction from flow, which are considered to be the basic failure modes of crustal rocks, and then the instability modes, sudden (caused by shear fracture or stick-slip) or gradual (caused by creep flow). It is obvious that the traditional strength criterion will not be able to predict these deformation events.On the basis of experimental results, the following conclusions have been drawn:1. The limited strength of middle-lower crustal rocks varies in some range, the upper limit is given from shear fracture strength of intact rocks, and the lower limitfrom frictional strength of rocks with saw-cut. In relatively deep part of the crust, the lower limit will be given from the limited flow stress, which can also be expressed as limited strain. Generally, fracture failure, which mainly occurs in upper-middle part of the crust, is limited-stress-dependent, and flow failure, which is more often observed in lower part of the crust, is limited-strain-dependent.2. Traditional strength criterion can only be used to identify the failure conditions and failure modes (fracture or flow), but can not reflect the instability modes. A new multicri-terion has been set up to identify the instability modes of rocks. An empirical criterion for this purpose has been given in form of critical stress or the plastic component.3. The semi-brittle failure mechanisms and the corresponding instability modes of crustal rocks can be classified by cal culating the critical stress and strength of rocks using the suggested multicriterion, and then a deformation-failure mechanism diagram can be drawn out, which directly reflects the relationship between environment (such as temperature and pressure) and rock failure-instability modes at relatively high stress, as well as the possible distribution of creep failure by different mechanisms.

In this paper,the authors studied the distributing characteristics of collapses and landslides during strong historic earthquakes in China and found that they are mainly distributed in regions with frequent strong earthquakes and complex topograph,especially in the South North Earthquake belt.Types and occurrence conditions of such earthquake disasters were analyzed.With reference to the data of collapses and landslides during modern earthquakes,the mechanism of slope's unstability was studied.