scholarly journals Analytical Study of the Confining Medium Diameter Impact on Load-Carrying Capacity of Rock Bolts

2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
Jianhang Chen ◽  
Xin Dai ◽  
Junwen Zhang
Keyword(s):  
Carrying Capacity ◽  
Experimental Tests ◽  
Load Carrying Capacity ◽  
Rock Bolts ◽  
Rock Reinforcement ◽  
Variation Trend ◽  
Analytical Work ◽  
Load Carrying ◽  
The Impact ◽  
Medium Diameter

The force transfer of fully grouted rock bolts is playing a significant effect in determining the rock reinforcement quality. To evaluate the performance of rock bolts, laboratory pulling tests were commonly used. Experimental tests proved that the confining medium diameter had an effect on the rock bolting performance. However, little analytical work has been performed to investigate the impact of the confining medium diameter on rock bolt load-carrying capacity. Therefore, this paper analytically studied the confining medium diameter effect on the load-carrying capacity of rock bolts. It was found that the load-carrying capacity of rock bolts was obviously affected by the confining medium diameter. Moreover, the larger the confining medium diameter, the higher the load-carrying capacity of rock bolts. However, the ascending rate of the load-carrying capacity gradually declined. This load-carrying capacity variation trend consistently agreed with experimental results. Moreover, with the confining medium diameter ascending, the load-carrying capacity variation trend was consistent when the confining medium modulus was under different levels. Last, it was found that, with the confining medium modulus ascending, the critical influence diameter gradually dropped.

scholarly journals Quantifying the Impact of Mounted Load Carrying on Equids: A Review

Animals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1333
Author(s):  
Syed S. U. H. Bukhari ◽  
Alan G. McElligott ◽  
Rebecca S. V. Parkes
Keyword(s):  
Carrying Capacity ◽  
Creatine Kinase Activity ◽  
Serum Cortisol Level ◽  
Load Carrying Capacity ◽  
Gait Symmetry ◽  
Brick Kilns ◽  
Potential Marker ◽  
Load Carrying ◽  
The Impact ◽  
Working Equids

There are approximately 112 million working equids in developing countries, many of which are associated with brick kilns. Brick kilns and overloading are associated with welfare problems in working equids. Understanding equids’ abilities and influencing factors are important for both effective performance and welfare. Traditionally, measurement of the amount of ‘bone’ was used, and more recently, gait symmetry has been identified as a potential marker for loading capacity. Assessment of stride parameters and gait kinematics provides insights into adaptations to loading and may help determine cut-off loads. Physiological factors such as the ability to regain normal heart rates shortly after work is an important tool for equine fitness assessment and a more accurate measure of load-carrying capacity than absolute heart rate. Oxidative stress, plasma lactate, and serum creatine kinase activity are reliable biochemical indicators of loading ability. For monitoring stress, salivary cortisol is superior to serum cortisol level for assessment of hypothalamus-pituitary-adrenal axis and is related to eye temperatures, but this has yet to be interpreted in terms of load-carrying ability in equids. Further research is needed to standardize the evidence-based load-carrying capacity of working horses and donkeys.

scholarly journals A STUDY OF FERROFLUID LUBRICATION BASED ROUGH SINE FILM SLIDER BEARING WITH ASSORTED POROUS STRUCTURE

2019 ◽  
Vol 59 (2) ◽  
pp. 144-152
Author(s):  
Mohmmadraiyan M. Munshi ◽  
Ashok R. Patel ◽  
Gunamani B. Deheri
Keyword(s):  
Porous Structure ◽  
Carrying Capacity ◽  
Graphical Representation ◽  
Negative Impact ◽  
Positive Impact ◽  
Numerical Approach ◽  
Load Carrying Capacity ◽  
Slider Bearing ◽  
Load Carrying ◽  
The Impact

This paper attempts to study a ferrofluid lubrication based rough sine film slider bearing with assorted porous structure using a numerical approach. The fluid flow of the system is regulated by the Neuringer-Rosensweig model. The impact of the transverse surface roughness of the system has been derived using the Christensen and Tonder model. The corresponding Reynolds’ equation has been used to calculate the pressure distribution which, in turn, has been the key to formulate the load carrying capacity equation. A graphical representation is made to demonstrate the calculated value of the load carrying capacity which is a dimensionless unit. The numbers thus derived have been used to prove that ferrofluid lubrication aids the load carrying capacity. The study suggests that the positive impact created by magnetization in the case of negatively skewed roughness helps to partially nullify the negative impact of the transverse roughness. Further investigation implies that when the Kozeny-Carman’s model is used, the overall performance is enhanced. The Kozeny-Carman’s model is a form of an empirical equation used to calculate permeability that is dependent on various parameters like pore shape, turtuosity, specific surface area and porosity. The success of the model can be accredited to its simplicity and efficiency to describe measured permeability values. The obtained equation was used to predict the permeability of fibre mat systems and of vesicular rocks.

Compensating the flexibility uncertainties of a cable suspended robot using SMC approach

Robotica ◽  
2014 ◽  
Vol 33 (3) ◽  
pp. 578-598 ◽  
Author(s):  
M. H. Korayem ◽  
M. Taherifar ◽  
H. Tourajizadeh
Keyword(s):  
Sliding Mode ◽  
Longitudinal Vibration ◽  
Experimental Tests ◽  
Sliding Mode Controller ◽  
Parametric Uncertainties ◽  
Load Carrying Capacity ◽  
Load Carrying ◽  
Varying Length ◽  
The Impact ◽  
Positive Effect

SUMMARYA sliding mode controller is designed to compensate for the flexibility uncertainties of a cable robot and improve its tracking performance. Of the most significant sources of these uncertainties are the elasticity of the cables and the flexibility of the joints. A favorable approach to improve the accuracy of the system is first to model the cable and joint flexibilities and then convert the model uncertainties into parametric uncertainties. Parametric uncertainties are the product of imprecise flexibility coefficients and are finally neutralized by a sliding mode controller. The flexibility in cables is modeled by considering the longitudinal vibration of the time-varying length cables. A simulation study is carried out to confirm the presented model and the positive effect of the designed controller. Then the impact of these uncertainties on the dynamic load carrying capacity (DLCC) of the robot is examined and compared for different cases. Finally, experimental tests are conducted on the IUST (Iran University of Science and Technology) cable-suspended robot to validate the presented theories and simulation results.

scholarly journals Response of Skirted Foundations Resting on Dry Medium Dense Sand

2018 ◽  
Vol 4 (6) ◽  
pp. 1193 ◽  
Author(s):  
Lujain Haider ◽  
Haider M. Mekkiyah
Keyword(s):  
Cross Section ◽  
Carrying Capacity ◽  
Considerable Increase ◽  
Experimental Tests ◽  
Load Carrying Capacity ◽  
Dense Sand ◽  
Load Carrying ◽  
Different Diameters ◽  
Large Soil ◽  
Settlement Behaviour

Experimental model tests were carried out to study the response of skirted foundation resting on dry sand.  The experiments were performed in a large soil container (1000  1000 mm in cross section and 800 mm in height).  Skirts with three different lengths (L) varied from 0.5D to 1.5D was attached to the edge of shallow circular foundations having three different diameters (D=60, 90 and 120 mm). Different parameters have been studied; these parameters involve skirt length, foundation size and skirt conditions. Skirts with open end and closed end were used. The relative density was kept constant and equals to 60%. The case of foundation without skirt (L=0) was initially tested and set as a reference for comparison purpose. From the results of experimental tests, it was found that the skirt modifies the load-settlement behaviour, increasing the load carrying capacity and reducing the foundation settlement. The results also indicate that load carrying capacity of skirted foundation increases with increase skirt length as well as foundation size. The results show that using skirt with closed end brought a considerable increase in load carrying capacity than that of open end.

scholarly journals Stability and Load-Carrying Capacity of Thin-Walled FRP Composite Z-Profiles under Eccentric Compression

Materials ◽  
2020 ◽  
Vol 13 (13) ◽  
pp. 2956
Author(s):  
Hubert Debski ◽  
Sylwester Samborski ◽  
Patryk Rozylo ◽  
Pawel Wysmulski
Keyword(s):  
Composite Material ◽  
Carrying Capacity ◽  
Progressive Failure ◽  
Compressive Load ◽  
Experimental Tests ◽  
Numerical Results ◽  
Load Carrying Capacity ◽  
Plastic Composite ◽  
Load Carrying ◽  
Thin Walled

This study investigates the effect of eccentric compressive load on the stability, critical states and load-carrying capacity of thin-walled composite Z-profiles. Short thin-walled columns made of carbon fiber-reinforced plastic composite material fabricated by the autoclave technique are examined. In experimental tests, the thin-walled structures were compressed until a loss of their load-carrying capacity was obtained. The test parameters were measured to describe the structure’s behavior, including the phenomenon of composite material failure. The post-critical load-displacement equilibrium paths and the acoustic emission signal enabling analysis of the composite material condition during the loading process were measured. The scope of the study also included performing numerical simulations by finite element method to solve the problem of non-linear stability and to describe the phenomenon of composite material damage based on the progressive failure model. The obtained numerical results showed a good agreement with the experimental characteristics of real structures. The numerical results are compared with the experimental findings to validate the developed numerical model.

scholarly journals Small Scale Experiments to Assess the Bearing Capacity of Footings on the Sloped Surface

Eng ◽  
2020 ◽  
Vol 1 (2) ◽  
pp. 240-248
Author(s):  
Mohammad Nurul Islam
Keyword(s):  
Bearing Capacity ◽  
Carrying Capacity ◽  
Maximum Load ◽  
Scale Model ◽  
Small Scale ◽  
Load Carrying Capacity ◽  
Engineering Structures ◽  
Load Carrying ◽  
Limiting Condition ◽  
The Impact

Construction of civil engineering structures on or next to a slope requires special attention to meet the bearing capacity requirements of soils. In this paper, to address such a challenge, we present laboratory-scale model tests to investigate the effect of footing shape on the sloped surface. The model comprised of a well stiffened mild steel box with three sides fixed and one side open. We considered both with and without reinforcement to assess the effectiveness of reinforcement on the sloped surface. Also, we used three types of footing (i.e., square, rectangular, and circular) to measure the footing shape effects. We considered three different slope angles to evaluate the impact of the sloped face corresponding to the applied load and the reinforcement application. We obtained that the maximum load carrying capacity in the square footing was higher than the rectangular and the circular footing for both the reinforced and the unreinforced soil. With the increase of geo-reinforcement in all three footing shapes and three sloped angles, the load carrying capacity increased. We also noticed a limiting condition in geo-reinforcement placement effectiveness. And we found that with the increase of slope, the load bearing capacity decreased. For a steep slope, the geo-reinforcement placement and the footing shape selection is crucial in achieving the external load sustainability, which we addressed herein.

Gun Bullet Deformation Analysis for Protection Board Development

2013 ◽  
Vol 577-578 ◽  
pp. 409-412
Author(s):  
Hidetoshi Sakamoto ◽  
Yoshifumi Ohbuchi ◽  
Hiroyuki Kuramae
Keyword(s):  
Carrying Capacity ◽  
Impact Load ◽  
Fem Analysis ◽  
Deformation Analysis ◽  
Load Carrying Capacity ◽  
Collision Velocity ◽  
3 Dimensional ◽  
Load Carrying ◽  
And Performance ◽  
The Impact

In this paper, the effects of collision velocity on bullet deformation were discussed and performance of protection board made of PC (polycarbonate) plate was estimated. The deformation of the bullet and the PC board after collision were measured by 3-dimensional digitizing machine.Furthermore, the bullet collision analysis was performed by FEM analysis code "LS-DYNA", and the impact load carrying capacity of PC plate was discussed by comparing the experimental results with the analytical ones

Use of nondestructive testing to establish mechanistic-based seasonal load-carrying capacity of thin-paved highways in Saskatchewan

2008 ◽  
Vol 35 (7) ◽  
pp. 708-715 ◽  
Author(s):  
Curtis Berthelot ◽  
Erin Stuber ◽  
Diana Podborochynski ◽  
Jena Fair ◽  
Brent Marjerison
Keyword(s):  
Carrying Capacity ◽  
Structural Integrity ◽  
Rate Of Change ◽  
Load Carrying Capacity ◽  
Road Transportation ◽  
Load Carrying ◽  
Frost Depth ◽  
Thaw Depth ◽  
The Impact

It has long been known that increased load-carrying capacity during the winter months is very beneficial to rural road transportation in Saskatchewan. However, it has been observed that rapid weakening of thin-paved roads during spring thaw is highly detrimental to the load-carrying capacity of these roads. Direct measures of the structural integrity of Saskatchewan roads as a function of seasonal changes have not been quantified in the past. The objective of this study was to directly quantify the impact frost action has on the load-carrying capacity of thin-surfaced roads. This study examined the magnitude and rate of change of in situ structural deflection responses of a typical Saskatchewan thin-surfaced road during fall freeze-up and spring thaw in 2006–2007. This study showed that structural deflection responses significantly improved with frost depth greater than 50 cm and that deflection response significantly worsened with minimal thaw depth, as expected. The data obtained also indicated a significant increase in nonlinear strain weakening behavior during fall freeze-up at frost depths less than 50 cm. Therefore, based on the findings of this study, the frost thickness and the rate of change in frost thickness need to be directly considered in the fall and in the spring when calculating seasonal load limits of thin-paved roads.

scholarly journals Investigation on Flexural Behaviour of Cold Formed Latticed Built-Up Beam

2021 ◽  
Vol 11 (3) ◽  
Author(s):  
Vishnu Vardan.A ◽  
Kaarthik. M
Keyword(s):  
Carrying Capacity ◽  
Ultimate Load ◽  
Flexural Behavior ◽  
Load Carrying Capacity ◽  
Structural Members ◽  
Load Carrying ◽  
Cold Formed Steel ◽  
Ultimate Load Carrying Capacity ◽  
Hot Rolled ◽  
The Impact

There are two structural members used in steel construction the hot rolled members and the cold formed members. They are light members compared to the traditional heavier hot rolled steel structural members used in the field. They have high strength to weight ratio resulting in less dead weight making it a good option in construction of bridges roof trusses transmission line towers multi storied buildings and other structural members. This paper is done to understand the flexural capacity and to enhance it by developing innovative latticed cold formed steel beam. The impact of web opening of the cold formed beam on the flexural behavior of cold formed built-up I section under two point loading is investigated for the simply supported end conditions. Numerical analysis is performed using finite element analysis (FEM) software. From results, the load vs. Deflection curve, failure modes and ultimate load carrying capacity of the specimen presented in this paper. Therefore the main focus of this project is to investigate the flexural behavior of these steel members and by replacing the lattice hot rolled section by cold formed steel sections. The ultimate load carrying capacity with failure mode of simulated FEA models was compared with experimental results.

The Impact of Linear Deformations on Stationary Hydrostatic Thrust Bearings

2002 ◽  
Vol 124 (4) ◽  
pp. 874-877 ◽  
Author(s):  
Noah D. Manring ◽  
Robert E. Johnson ◽  
Harish P. Cherukuri
Keyword(s):  
Pressure Distribution ◽  
Closed Form ◽  
Flow Rate ◽  
Carrying Capacity ◽  
Thrust Bearing ◽  
Load Carrying Capacity ◽  
Thrust Bearings ◽  
Load Carrying ◽  
Number Flow ◽  
The Impact

In this work, the operating sensitivity of the hydrostatic thrust bearing with respect to pressure-induced deformations will be studied in a stationary setting. Using the classical lubrication equations for low Reynold’s number flow, closed-form expressions are generated for describing the pressure distribution, the flow rate, and the load carrying capacity of the bearing. These expressions are developed to consider deformations of the bearing that result in either concave or convex shapes relative to a flat thrust surface. The impact of both shapes is compared, and the sensitivity of the flow rate and the load carrying capacity of the bearing with respect to the magnitude of the deformation is discussed. In summary, it is shown that all deformations increase the flow rate of the bearing and that concave deformations increase the load carrying capacity while convex deformations decrease this same quantity relative to a non-deformed bearing condition.

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