Application of Combined Anti-Slide Micro-Piles to Control of a Landslide in Xining-Jiuzhi Highway

2012 ◽  
Vol 204-208 ◽  
pp. 1673-1677
Author(s):  
Sheng Li Tang ◽  
Le Zhou ◽  
Zhang Wu ◽  
Xiao Long Dang
Keyword(s):  
Composite Structure ◽  
Deep Layer ◽  
Superficial Layer ◽  
Comprehensive Treatment ◽  
Specific Circumstance ◽  
Landslide Stability ◽  
Load Carrying ◽  
Engineering Measures ◽  
Pressure Grouting ◽  
The Stability

It is a new trend to control landslide by using anti-sliding composite structure of micro-piles combined with other engineering measures. It has been applied in many engineer practices for its convenient, less cost, and high landslide stability increased obviously by the pressure grouting. The paper discussed formation lithology, geologic structure and hydrogeology features of Xining-Jiuzhi highway as an example, according to the specific circumstance of sliding zones in superficial layer and deep layer, we proposed a comprehensive landslide treatment, combined with anti-sliding composite structure of micro-piles, anchor cable frame reinforcing and inclined drain holes. On the basis of analyzing the effect and theory of consolidating the slide by anti-sliding composite structure of micro-piles, we adopted the numerical model of lagrange finite-difference analyzing the stability of landslides and the load-carrying properties of the reinforced structure before and afterwards comparatively. The calculated results and monitoring showed that: the landslides were stable, and the comprehensive treatment of using anti-sliding composite structure of micro-piles has met the expectant control effects.

Model Test and Application Research of Micro-Pile on Landslide Control

2014 ◽  
Vol 522-524 ◽  
pp. 141-146
Author(s):  
Sheng Li Tang ◽  
Le Zhou ◽  
Bei Bei Han
Keyword(s):  
Model Test ◽  
Composite Structure ◽  
Low Cost ◽  
Engineering Practice ◽  
Application Research ◽  
Grouting Pressure ◽  
Engineering Measures ◽  
The Stability ◽  
Supporting Force

It is a new trend to control landslide by using anti-sliding composite structure of micro-piles combined with other engineering measures. At present, it is extensively applied to engineering practice for convenient construction, low cost, grouting pressure enhances the stability of landslide strikingly etc. Based on the analysis of the mechanism anti-sliding of micro-pile, characteristics of micro-piles under horizontal supporting force are studied by modest test. Finally, checking the sheer stability of micro-pile and combining with engineering example proves the feasibility and reliability of micro-pile on landslide control.

Effect of Load Carrying on Local Dynamic Stability

2007 ◽  
Vol 51 (15) ◽  
pp. 909-913 ◽  
Author(s):  
Jian Liu ◽  
Thurmon E. Lockhart ◽  
Kevin Granata
Keyword(s):  
Dynamic Stability ◽  
Load Condition ◽  
Local Dynamic ◽  
Fall Injuries ◽  
Local Dynamic Stability ◽  
Load Carrying ◽  
Trunk Acceleration ◽  
The Stability ◽  
Major Factors

Occupational load carrying tasks are considered one of the major factors contributing to slip and fall injuries. The objective of the current study was to explore the feasibility to assess the stability changes associated with load carrying by local dynamic stability measures. Twenty-five young participants were involved in a treadmill walking study, with their trunk acceleration profiles measured wirelessly by a tri-axial accelerometer. Finite time local dynamic stability was quantified by maximum Lyapunov exponents (maxLE). The results showed a significant increase in long term maxLE in load condition, indicating the declined local dynamic stability due to the load carrying. Thus, current study confirmed the discriminative validity and sensitivity of local dynamic stability measure and its utility in the load carrying scenario.

Analysis the characteristic of energy and damage of coal-rock composite structure under cycle loading

2021 ◽  
Author(s):  
Tan Li ◽  
Guangbo Chen ◽  
Zhongcheng Qin ◽  
Qinghai Li
Keyword(s):  
Cyclic Loading ◽  
Elastic Energy ◽  
Composite Structure ◽  
Calculation Method ◽  
Composite Structures ◽  
Damage Variable ◽  
Dissipated Energy ◽  
Height Ratio ◽  
Coal Rock ◽  
The Stability

Abstract The stability of coal-rock composite structures is of great significance to coal mine safety production. To study the stability and deformation failure characteristics of the coal-rock composite structure, the uniaxial cyclic loading tests of the coal-rock composite structures with different coal-rock height ratios were carried out. Lithology and coal-rock height ratio play an important role in the energy dissipation of coal-rock composite structures. The higher the coal-rock height ratio, the greater the average elastic energy and dissipated energy produced per cycle of coal-rock composite structures, the smaller the total elastic energy and dissipated energy produced in the process of cyclic loading. Based on the difference of damage variables calculated by dissipative energy method and acoustic emission method, a more sensitive joint calculation method for calculating damage variable was proposed. The joint damage variable calculation method can more accurately and sensitively reflect the damage of coal-rock composite structure under cyclic loading. The macroscopic crack first appears in the coal specimen in the coal-rock composite structure, the degree of broken coal specimens in the composite structure is inversely proportional to the coal-rock height ratio. The strength and deformation characteristics of the coal-rock composite structure are mainly affected by coal sample in the composite structure.

On the Plastic Bending Responses of Dented Lined Pipe

2021 ◽  
Author(s):  
Lin Yuan ◽  
Jiasheng Zhou ◽  
Haowei Liu ◽  
Nian-Zhong Chen
Keyword(s):  
Composite Structure ◽  
Cost Effective ◽  
Geometric Feature ◽  
Load Carrying Capacity ◽  
Bending Process ◽  
Load Carrying ◽  
Bending Capacity ◽  
Critical Curvature ◽  
Ultimate Load Carrying Capacity ◽  
Local Dent

Abstract Mechanically lined pipe, which was proven to be cost-effective in transporting corrosive hydrocarbons, has been used in many offshore applications. However, one weakness of this product is that the liner is extremely sensitive to geometric imperfections and can wrinkle and collapse under severe loading. As typical damage of the pipeline, the local dent of the lined pipe involves the deformation of both the carrier pipe and the liner, which poses a severe threat to the integrity of the composite structure. In this paper, we developed a numerical framework to study the responses of the lined pipe during indentation and, more importantly, the influence of local dents on the bending capacity of lined pipes. A slight separation between the liner and the carrier pipe was observed during the indentation, depending on the indenter’s geometric feature. Under bending, the liner typically collapsed earlier than the carrier pipe, causing a considerable reduction of the critical curvature and ultimate load-carrying capacity. The evolution of the deformation of the composite structure during the bending process is presented in this paper. Parametric investigations of some vital variables of the problem were also performed to study their influence on the behavior under indentation and the bending capacity of the composite structure.

scholarly journals Gross anatomy of the narial and labial musculatures of one humped Camel (Camelus dromedarius)

2016 ◽  
Vol 33 (04) ◽  
pp. 171-178
Author(s):  
Z. Adam ◽  
A. Awaad ◽  
M. Tawfiek ◽  
A. Ibrahim
Keyword(s):  
Deep Layer ◽  
Gross Anatomy ◽  
Middle Layer ◽  
Superficial Layer ◽  
Living Conditions ◽  
Camelus Dromedarius ◽  
Nerve Supply ◽  
Levator Labii Superioris ◽  
The One

Abstract Introduction: The objective of this study was to clarify the anatomy of the narial and labial musculatures of the one-humped camel (Camelus dromedarius) and their nerve supply. Materials and Methods: Sixteen head specimens from adult and symptomatically healthy camels of both sexes were used. The muscles of the nostrils and lips were carefully dissected and illustrated to demonstrate their origin, insertion and relations. The nerves in this area were also dissected to show their branches and distribution. Results: The dissection of these regions revealed that their muscles were arranged in three layers; the superficial layer included M. dilator naris apicalis, M. dilator naris medialis and M. levator nasolabialis, the middle layer was formed of maxillo-labial group of muscles (M. levator labii superioris, M. dilator naris lateralis and M. depressor labii superioris) and the deep layer was formed by M. lateralis nasi. Moreover, the lips had M. orbicularis oris, M. incisivus superioris, M. incisivus inferioris and M. mentalis, however, the M. depressor labii inferioris was absent in the animal under investigation. The muscles of nostrils and lips were innervated by N. trigeminus (V) and N. facialis (VII). Conclusion: The arrangement of the narial and labial muscles is unique and may relate to its living conditions of frequent sand-storms and direct sun rays, where the camel is the only domesticated animal known for its ability to close its nostril.

Differences in voltage-dependent sodium currents exhibited by superficial and deep layer neurons of guinea pig entorhinal cortex

1994 ◽  
Vol 71 (5) ◽  
pp. 1986-1991 ◽  
Author(s):  
S. Fan ◽  
M. Stewart ◽  
R. K. Wong
Keyword(s):  
Guinea Pig ◽  
Entorhinal Cortex ◽  
Deep Layer ◽  
Sodium Current ◽  
Membrane Conductance ◽  
Cell Voltage ◽  
Superficial Layer ◽  
Peak Amplitude ◽  
Sodium Currents ◽  
Test Pulse

1. Sodium currents were studied using whole-cell voltage-clamp techniques in neurons acutely isolated from superficial (II/III) and deep (V/VI) layers of guinea pig entorhinal cortex. 2. Sodium currents were larger (peak amplitude) in superficial than in deep layer cells under the same conditions: -1939 +/- 780 (SD) pA (N = 6) versus -307 +/- 257 pA (N = 6). Specific membrane conductance was calculated to be 12.3 +/- 9.6 mS/cm2 for superficial layer cells and 1.4 +/- 0.9 mS/cm2 for deep layer cells. 3. Sodium currents could be activated in superficial layer cells from potentials as depolarized as -20 mV, whereas no significant currents could be activated in deep neurons from potentials more depolarized than about -50 mV. Using a protocol consisting of a 25-ms prepulse and a 20 ms test pulse, the inactivation curves for superficial layer cells were found to be shifted toward more depolarized potentials by an average of 15 mV (V50 = -59.8 +/- 3.8 mV compared with -75.7 +/- 12.0 mV for deep cells). This produced a region of overlap with the activation curves for superficial cells. 4. Over a range of about -50 to -20 mV in superficial layer cells, the region of overlap of the activation and inactivation curves, a sodium current could be activated, which did not fully inactivate during the test pulse (average peak amplitude: -89.5 +/- 48.7 pA; crossover voltage: -39.2 +/- 2.0 mV). Voltage steps to more depolarized potentials, outside the voltage “window”, permitted complete inactivation of the sodium current.(ABSTRACT TRUNCATED AT 250 WORDS)

Progressive Failure Analysis of an Integral Composite Joint for Thrust Reverser Cascade

2019 ◽  
Vol 795 ◽  
pp. 325-332
Author(s):  
Ji Shen Yang ◽  
Hong Yu Qi ◽  
Xiao Guang Yang ◽  
Duo Qi Shi
Keyword(s):  
Carrying Capacity ◽  
Composite Structure ◽  
Progressive Failure ◽  
Damage Model ◽  
Research Work ◽  
Failure Behavior ◽  
Load Carrying Capacity ◽  
Composite Joint ◽  
Bending Load ◽  
Load Carrying

The research work in this paper is focused on studying the failure behavior of an integral π-shaped laminated composite structure subjected to a bending load. A progressive damage model based on the 3D Tsai-Wu failure criterion and a developed gradual degradation model was employed to simulate and assess the load-carrying capacity, the onset and propagation of damage, and the failure mechanisms. For this unique π-shaped composite structure, disbonding was found to be the dominant damage mode under bending load, and the approximate maximum load could be maintained for a brief time during the final failure due to the gradual loss nature of the load-carrying capacity. The extent of damage was found to be more serious on the side of Rib II compared to the other side.

Dissimilar Metal Weld Pipe Fracture Testing: Analysis of Results and Their Implications

2012 ◽  
Author(s):  
D. Rudland ◽  
R. Lukes ◽  
P. Scott ◽  
R. Olson ◽  
A. Cox ◽  
...  
Keyword(s):  
Experimental Data ◽  
Carrying Capacity ◽  
Nuclear Industry ◽  
Load Carrying Capacity ◽  
Base Metals ◽  
Dissimilar Metal ◽  
Load Carrying ◽  
Estimation Scheme ◽  
The Stability ◽  
J Estimation

Typically in flaw evaluation procedures, idealized crack shapes are assumed for both subcritical and critical crack analyses. Past NRC-sponsored research have developed estimation schemes for predicting the load-carrying capacity of idealized cracks in nuclear grade piping and similar metal welds at the operating conditions of nuclear power reactors. However, recent analyses have shown that growth of primary water stress corrosion cracks (PWSCC) in dissimilar metal (DM) welds is not ideal; in fact, very unusual complex crack shapes may form, i.e., a very long surface crack that has a finite length through-wall crack in the same plane. Even though some experimental data on base metals exists to demonstrate that complex shaped cracks in high toughness materials fail under limit load conditions, other experiments demonstrate that the tearing resistance is significantly reduced. At this point, no experimental data exists for complex cracks in DM welds. In addition, it is unclear whether the idealized estimation schemes developed can be used to predict the load-carrying capacity of these complex-shaped cracks, even though they have been used in past analyses by the nuclear industry. Finally, it is unclear what material strength data should be used to assess the stability of a crack in a DM weld. The NRC Office of Nuclear Regulatory Research, with their contractor Battelle Memorial Institute, has concluded an experimental program to confirm the stability behavior of complex shaped circumferential cracks in DM welds. A combination of full-scale pipe experiments and a variety of laboratory experiments were conducted. A description of the pipe test experimental results is given in a companion paper. This paper describes the ongoing analyses of those results, and the prediction of the load-carrying capacity of the circumferential cracked pipe using a variety of J-estimation scheme procedures. Discussions include the effects of constraint, appropriate base metal material properties, effects of crack location relative to the dissimilar base metals, and the limitations of the currently available J-estimation scheme procedures. This paper concludes with plans for further development of J-estimation scheme procedures for circumferential complex cracks in DM welds.

Complex Crack Stability in Dissimilar Metal Welds: Background and Test Plan

2011 ◽  
Author(s):  
D. Rudland ◽  
P. Scott ◽  
R. Olson ◽  
A. Cox
Keyword(s):  
Experimental Data ◽  
Base Metal ◽  
Carrying Capacity ◽  
Nuclear Industry ◽  
Load Carrying Capacity ◽  
Dissimilar Metal ◽  
Load Carrying ◽  
Crack Stability ◽  
Complex Crack ◽  
The Stability

Typically in flaw evaluation procedures, idealized flaw shapes are assumed for both subcritical crack growth and critical crack stability analyses. Past NRC-sponsored research have developed estimation schemes for predicting the load-carrying capacity of idealized flaws in nuclear grade piping and similar metal welds at the operating conditions of nuclear power reactors. However, recent analyses have shown that growth of primary water stress corrosion cracks (PWSCC) in dissimilar metal (DM) welds is not ideal; in fact, very unusual complex crack shapes may form, i.e., a very long surface crack that has a finite length through-wall crack in the same plane. Even though some experimental data on base metal cracks exist to demonstrate that complex shaped cracks in high toughness materials fail under limit load conditions, other experiments demonstrate that the tearing resistance is significantly reduced. At this point, no experimental data exists for complex cracks in DM welds. In addition, it is unclear whether the idealized estimation schemes developed can be used to predict the load carrying capacity of these complex-shaped flaws, even though they have been used in past analyses by the nuclear industry. Finally, it is unclear what material strength data should be used to assess the stability of a crack in a DM weld. The NRC Office of Nuclear Regulatory Research (RES), with their contractor Battelle Memorial Institute, has begun an experimental program to confirm the stability behavior of these complex shaped flaws in DM welds. A combination of thirteen full-scale pipe experiments and a variety of laboratory experiments are planned. This paper will summarize the past base metal complex-cracked pipe experiments, and the current idealized flaw load carrying capacity estimation schemes. In addition, the DM weld complex cracked pipe experimental test matrix will be presented. Finally, plans for using these results to confirm the applicability of idealized flaw stability procedures are discussed.

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