Journal articles: 'Lining Thickness'

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Ossia, Chinwuba Victor, and Mathew Uzoma Shedrack. "Optimization of Blast Furnace Throughput Based on Hearth Refractory Lining and Shell Thickness." Journal of Casting & Materials Engineering 5, no. 1 (April 15, 2021): 5–13. http://dx.doi.org/10.7494/jcme.2021.5.1.5.

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Computational analyses were performed to optimize the furnace throughput, steel shell and lining thickness of a blast furnace. The computations were done for measured parameters within the hearth region as this is the vital zone of the furnace with high temperature fluctuations, molten iron, and slag production. The lining materials were namely 62% high alumina (A), carbon composite (B), silicon carbide (C) and graphite bricks (D) with thermal conductivities 2, 12, 120 and 135 W/(m∙K), respectively. It was observed that by varying the refractory lining thickness from 0.2–0.35 m, and furnace inside temperatures from 1873–2073 K, certain optimal conditions could be specified for the furnace under consideration. Silicon carbide and graphite brick linings which have higher thermal conductivities, melting points, good chemical and mechanical wear resistance were observed to be the best hearth lining materials. Due to the high thermal conductivities of these two materials, the hot face temperature levels of the lining materials would be lowered. Amongst the four lining materials employed, silicon carbide and graphite bricks when used with lining cooling systems could optimize the blast furnace for better performance, production, and longer campaigns.

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Shaalan, Heyam H., Romziah Azit, and Mohd Ashraf Mohamad Ismail. "Numerical Analysis of TBM Tunnel Lining Behavior using Shotcrete Constitutive Model." Civil Engineering Journal 4, no. 5 (June 3, 2018): 1046. http://dx.doi.org/10.28991/cej-0309155.

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Shotcrete is a fundamental support element for tunnels and underground constructions. Shortly after application, shotcrete linings undergo a high load while the ordinary concrete is not fully hardened yet. Therefore, the time-dependent behaviour of the shotcrete material must consider. Traditional approaches assume a linear elastic behaviour using a hypothetical young modulus to model this time-dependency and creep effects. In this paper, a new constitutive model of shotcrete is applied to evaluate the time-dependent behaviour of TBM tunnel lining under high in-situ stress state. The Shotcrete model is based on the framework of Elasto-plasticity and designed to account for non-linear and time-dependent behaviour for concrete material more realistically. A parametric study of the time-dependent behaviour of the shotcrete lining, using the shotcrete model, is performed. To achieve this, the influence of the lining thickness, tunnel diameter and tunnel depth on the development of the stresses and displacement of the shotcrete lining with time is investigated. The results showed that the development of the lining tensile stress with time at tunnel crown increases by increasing the lining thickness and tunnel depth, whereas it decreases by increasing of the tunnel diameter. At the tunnel sidewall, the lining compression stress with time increases with the increase of the tunnel depth and diameter, while higher lining thickness decreases the lining compressive stresses. However, the results showed the ability of the shotcrete model to simulate the structural behaviour of the shotcrete lining with time.

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Kang, Tae Ho, Sung Ho Joh, and Mi Ra Cho. "Structural Integrity Assessment of Tunnel Concrete Lining by the Resonance Search Technique." Key Engineering Materials 321-323 (October 2006): 302–5. http://dx.doi.org/10.4028/www.scientific.net/kem.321-323.302.

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Concrete lining of underground structures is one of structural elements to require the structural integrity assessment. In this paper, for the structural-integrity assessment of concrete lining, the resonance search (RS) technique based on stress-wave propagation is proposed. The RS technique is the combination of the Spectral-Analysis-of-Surface-Waves (SASW) method and the resonance method. In the RS method, the shear-wave velocity profile is first determined by the SASW measurements. Then, the thickness of concrete lining is determined using the search technique to match the measured resonant frequency and the theoretical resonant frequency evaluated by the numerical modeling. The validity of the proposed procedure was verified by the numerical simulations of the method, the field test at a test concrete lining and the practical application to a real concrete lining of tunnel ManDeok in Korea. The slab thicknesses obtained by coring and Ground Penetrating Radar (GPR) scanning were also compared with the thickness by the RS technique.

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Reddy, S. Nagalaxmi, DN Jayashankar, and Mohanthomas Nainan. "The Effect of Flowable Composite Lining Thickness with Various Curing Techniques on Microleakage in Class II Composite Restorations: An in vitro Study." Journal of Contemporary Dental Practice 14, no. 1 (2013): 56–60. http://dx.doi.org/10.5005/jp-journals-10024-1270.

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ABSTRACT Aim Aim of this study was to compare class II composite restoration using flowable composites as lining with various thickness and curing techniques by evaluating cervical marginal microleakage. Materials and methods Fifty intact molars, each prepared with two box-only class II cavities, were randomly divided into five groups: Group I, P60 filling alone; group II, ultrathin flowable composite lining (0.5-1mm) cocured with overlying composite; group III, thin lining (1-1.5) cocured with overlying composite; group IV, ultrathin lining (0.5-1 mm) precured and group V, thin lining (1-1.5) precured. The teeth were then thermocycled for 1500 cycles (between 5 and 60 °C) and immersed in dye for 24 hours. Cervical microleakage was measured as the extent of dye penetration. Results Cocured specimens (groups II and III) showed least microleakage and control specimens (group I) showed maximum microleakage. On comparison of curing techniques, cocured specimens (groups II and III) showed less microleakage than precured (groups IV and V). On comparison of lining thickness and type of curing, group IV showed less microleakage than group V. Groups II and III were statistically not significant. Conclusion It was concluded from the results that ultrathin cocured flowable composite lining specimens improved the marginal sealing with decreased microleakage. Clinical significance In this study, the application of additional flowable composite lining with various thicknesses presented different influences in marginal quality of class II box only composite restorations. A new technique applying an ultrathin flowable composite lining with cocuring technique improved the marginal sealing with decreased microleakage. Restorations with thin lining presented reduced marginal integrity after thermocycling. How to cite this article Reddy SN, Jayashankar DN, Nainan M, Shivanna V. The Effect of Flowable Composite Lining Thickness with Various Curing Techniques on Microleakage in Class II Composite Restorations: An in vitro Study. J Contemp Dent Pract 2013;14(1):56-60.

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Zhao, Hong Xin, Zhang Fu Yuan, Yan Wu, Yi Fang Pan, Shu Qing Li, Tao Qi, and Li Na Wang. "Study on Thickness Control and Quantitative of Converter Lining." Applied Mechanics and Materials 433-435 (October 2013): 2156–63. http://dx.doi.org/10.4028/www.scientific.net/amm.433-435.2156.

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The thickness control of lining is vital to the normal operation of converter. Vulnerable parts of the furnace would be found and repaired timely by applying thickness measuring technique by laser. According to the measured results, the load part of the facet of the converter is the weakest location of the lining in the early campaign life, while the section of the trunnion is the weakest in the middle campaign life. When it comes to the later stage of campaign, the erosion of lining is severe. In line with the quantification of erosion parts, the lining thickness range can be divided into three parts, which are safety smelting area, stability control area and dangerous area. The economic life of the furnace life, which is 20 to 23 thousand heats, can be maintained as the thinnest lining is still above the stable range when the campaign reaches mid-late period.

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Han, Xianmin, and Wenjiang Li. "Numerical Analysis on the Structure Type and Mechanical Response of Tunnel Crossing Active Reverse Fault." Geofluids 2021 (August 18, 2021): 1–10. http://dx.doi.org/10.1155/2021/5513042.

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Faulting would result in ground deformation and even damage to the tunnel structure. Thus, special structural designs should be made when the tunnel passes through an active fault. A single-track railway tunnel crossing a reverse fault is used to study the suitable structure type. In this paper, antidislocation structural measures such as reasonable segment length of articulated lining, cross-section shape, and thickness of lining are discussed through the numerical simulation. Firstly, the rational segment length of the articulated lining is confirmed. Stress and deformation behavior of articulated lining are also analyzed after the fault move. Then, the antifault effect of two kinds of cross-section shapes and three different lining thicknesses are compared. Researches show that the segment length of the articulated lining could be confirmed by the longitudinal distribution of maximum bending moment of lining after faulting. There are apparent stress concentrations occurring in the lining segment crossing the fault plane, and serious damage appears in the vault and wall waist of the tunnel. The horseshoe section with big curvature inverted arch is recommended to a single-track railway tunnel across an active fault. Simply increasing lining thickness is not suggested in a tunnel structure design crossing the active fault. The size of tunnel expansion and the minimum length of segment across fault plane can be geometrically determined according to fault dislocation magnitude and dip angle.

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Niu, Ze Lin. "Optimization Design of Single Track Railway Tunnel Lining Structure." Applied Mechanics and Materials 638-640 (September 2014): 813–16. http://dx.doi.org/10.4028/www.scientific.net/amm.638-640.813.

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Based on the traditional safety coefficient method,Continuum Model and single track railway tunnel lining structure, the paper does numerical simulation calculates and compares effects of actions on tunnel lining structure, analyses and get the effect of actions in different section of tunnel lining.According to the tunnel lining element’s safety coefficient and standard requirements, reasonable lining structure thickness is gave by comparison and optimization of lining structure thickness,and this provides the theory support for the structure design of track railway tunnel .

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Qin, Gan, Shengrong Cao, and Fan Yang. "Effect of Deficiencies in the Tunnel Crown Thickness on Pressure Tunnels with Posttensioned Concrete Linings." Advances in Civil Engineering 2018 (July 11, 2018): 1–14. http://dx.doi.org/10.1155/2018/2757542.

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This paper investigates the effect of deficiencies in the tunnel crown thickness on pressure tunnels with the posttensioned concrete lining. Based on the lining parameters of the Yellow River Crossing Tunnel, the modeling approach of the posttensioned concrete lining is introduced in detail and a three-dimensional finite element model is established. The three-dimensional finite element model is validated by experimental results from the full-scale model experiment of the Yellow River Crossing Tunnel. Special attention is given to the changes in the deformation, radial displacement, and circumferential stress of the posttensioned concrete lining with gradual decreases in the tunnel crown thickness. The calculation results show that the influence scopes of deficiencies in the tunnel crown thickness are mainly concentrated in the crown and its adjacent parts. The posttensioned concrete lining can still maintain a satisfactory stress state when deficiencies in the tunnel crown thickness exist, and undesirable stress levels may be caused only when the tunnel crown thickness decreases below a certain threshold. Furthermore, cracks are most likely to occur at the external and internal surfaces of the crown and at the internal surface of the crown’s adjacent parts, which is useful for taking measurements regarding the lining tightness and stability.

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Yan, Qi-xiang, Chao-fan Yao, Wen-bo Yang, Chuan He, and Ping Geng. "An Improved Numerical Model of Shield Tunnel with Double Lining and Its Applications." Advances in Materials Science and Engineering 2015 (2015): 1–15. http://dx.doi.org/10.1155/2015/430879.

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Based on the existing numerical models of shield tunnel with double lining, an improved numerical model is developed and its rationality is verified by a similar model test. In the improved numerical model, lining, joint, and junction surface, respectively, are simulated by beam, spring, and a combination of compression bar and spring. Through the comparison of the numerical analysis results of the improved model and existing models, it turns out that the defects or problems in the existing numerical models are resolved; tension appearance on the contact surface and junction surface and the abrupt change of bending moment in linings are solved in the improved model because the compression bar element and the coupling technology of node displacement in the junction surface is applied. Therefore, the improved numerical model could be applied to analyze double lining with waterproof on the junction surface and separation of the junction surface under an unfavorable load. In this paper, the parameter formulas of element stiffness, applicable to the junction surface and contact surface of double lining, are given definitely, and the influence of the element amount of junction surface on the analysis results is discussed. Based on the improved numerical model, the mechanical behavior of the double lining of the Huangpu River Tunnel in China is studied, and some conclusions are obtained as follows. (1) The thickness increase of the double lining will clearly increase its bending moment, but it has little influence on its axial force. (2) The allocation proportion of the bending moment between the segment lining and secondary lining has no linear relationship with the ratio of the lining thickness.

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Lu, Ling, and Yang Zhao. "Study on Dynamic Characteristics of Circular Tunnel Concrete Lining." Applied Mechanics and Materials 438-439 (October 2013): 1129–32. http://dx.doi.org/10.4028/www.scientific.net/amm.438-439.1129.

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The dynamic characteristics of concrete lining of a circular tunnel was studied combined with the Dahuofang water-conveyance project. The first ten frequencies and modes of vibration were presented. The influence of some factors on the vibration performance of the concrete lining were analyzed, i.e. buried depth, lining thickness, youngs modulus of rock, and water in the tunnel. The results show that the buried depth and the youngs modulus of rock have greater influence on the vibration performance of concrete lining than the lining thickness and the water in the tunnel. Some aseismic measures are given out for the similar engineering.

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11

Zhou, Hai Ying, Li Xin Li, and Ting Guo Chen. "An Approach to Determine the Stiffness Reduction Factor of Tunnel Lining." Advanced Materials Research 243-249 (May 2011): 3659–62. http://dx.doi.org/10.4028/www.scientific.net/amr.243-249.3659.

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Based on the segmental joint tests, it was found that the practical range of joint flexural rigidity was in range of 8500-29000kN•m/rad. A simplified method for determining the stiffness reduction factor of tunnel lining() was proposed using results from the segmental joint tests in which some parameters were obtained by calibration against a 3D Numerical analysis. The influence of joint flexural rigidity, soil resistance coefficient, thickness of tunnel lining and tunnel calculation radius on the stiffness reduction factor of tunnel lining was examined. The stiffness reduction factor can be simply expressed as a function of joint flexural rigidity ratio, soil resistance coefficient, thickness of tunnel lining and tunnel calculation radius for the typical tunnel lining.

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Wang, Jiling, Lifeng Zhang, Shufeng Yang, Yongfeng Chen, Jingyu Li, and Alexander Wachsman. "Interaction between Molten Steel, Alumina Lining Refractory and Slag Phase." Journal for Manufacturing Science & Production 13, no. 1-2 (April 17, 2013): 133–43. http://dx.doi.org/10.1515/jmsp-2012-0036.

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AbstractLaboratory experiments exploring the interaction between molten steel, slag and lining refractory were performed. The transient erosion and reaction over time were investigated, and the transient change of the reaction layer and inclusions generated in the molten steel were evaluated using optical microscopy and SEM-EDS. Without slag addition before remelting, the FeO from reoxidation entered the space between the lining refractory and the steel and strengthened the erosion of the lining refractory. Several layers were found from the steel to the original lining refractory layer: steel phase, FeO layer, a FeO-rich lining layer and an Original Lining (OL)-rich lining layer. The thickness of the reaction layer increased nearly linearly with the reaction time at an erosion rate of 4.2 µm/min. With slag addition before remelting, the reaction layer between the steel and the original lining materials included several sub-layers: a gap, a slag layer, an FeO-rich lining layer and an Original Lining (OL)-rich lining layer. The thickness of the reaction layer nearly linearly increased with the reaction time and with an erosion rate of 5.7 µm/min. Slags were entrained into the steel occasionally.

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Petkov, Venko, Mincho Hadjiski, and Kosta Boshnakov. "Diagnosis of Metallurgical Ladle Refractory Lining Based on Non-Stationary On-Line Data Processing." Cybernetics and Information Technologies 13, no. 2 (June 1, 2013): 122–30. http://dx.doi.org/10.2478/cait-2013-0020.

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Abstract A new method for diagnosis of the remaining thickness of metallurgical ladle refractory lining working in a batch mode is proposed, where directly measured by a thermovision camera data about the amplitude and phase delay of the maximum surface temperature is used. Regression equations are obtained to determine the remaining thickness of the ladle refractory lining depending on the parameters of steady auto oscillations of the maximum surface temperature. It is shown that the data from nonstationary auto oscillations could be used for adaptation of the regression equations, predicting the remaining thickness of the ladle refractory lining in case of a local damage.

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Yu, Xiang Jun, Ji Xin Wang, and Yong Li. "Study of Fluid-Solid Simulation on the Large-Scale Hydrostatic Bearing of Hollow Coaxial." Materials Science Forum 628-629 (August 2009): 281–86. http://dx.doi.org/10.4028/www.scientific.net/msf.628-629.281.

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In order to investigate the changing law of the film thickness caused by the deformation of hollow coaxial and drum-shaped lining and accurately calculate the stress of hollow coaxial and rum-shaped lining, the fluid-solid numerical simulatied model of a large-scale hydrostatic bearing was established. The stress and deformation of hollow coaxial and drum-shaped lining was obtained by indirect coupled methods. The typical impact factors and the deformation laws of the thinnest film were discussed. The simulation results indicate that the maximum stress locatioes on the drum-shaped lining and hollow coaxial; and the deformation of the hollow coaxial is 60.47 times that of the drum-shaped lining, and the oil film thinnest thickness decreases by 12.1% due to the deformation of the hollow coaxial and drum-shaped lining; and the stiffness of the hollow coaxial makes greatest impact on oil film deformation.

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Dmitriev, A. N., M. O. Zolotykh, K. Chen', and G. Yu Vit'kina. "Comparative technological analysis of control systems of blast furnace hearth lining deterioration." Ferrous Metallurgy. Bulletin of Scientific , Technical and Economic Information, no. 8 (September 1, 2018): 82–91. http://dx.doi.org/10.32339/0135-5910-2018-8-82-91.

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For safe and effective operation of a blast furnace it is important to know the residual thickness of the blast furnace hearth lining any time, first of all the location of the damaged arears. Use of traditional methods of hearth and bottom lining control often lead to a mistaken diagnostics.Institute of metallurgy of Ural branch of RussianacademyofScienceselaborated a mathematical model, providing a 3-dimentional estimation of the lining status and optimization of calculations for operation in real time mode.The calculation is done by solving equations of heat conductivity by usage of a number of temperature sensors (up to 700), implemented into furnace lining between refractory blocks. Calculation algorithm was modified by application of sampling theorem to take into account the complex profile of the blast furnace lower part. A system of information collection, processing and passing used from the sensors to program data base. A continuous control of temperature variation in every point enables to determine a current lining refractory thickness and notify the furnace personal in advance about beginning of the lining erosion. The elaborated program interface enables the furnace foreman to use additional control functions, in particular, the residual lining thickness, including: direct visualization of the status and tendencies of the erosion change, temperature distribution in every point of the lining at computer monitor, signaling about dangerous zone; volume temperature distribution (isotherms) and tendencies of their changes. The interface languages available as following: Chinese, English, Russian.

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Antipkina, M. E., S. A. Krupennikov, and I. A. Levitskii. "Determination of Optimum Lining Thickness for a Heating Furnace." Refractories and Industrial Ceramics 60, no. 5 (January 2020): 510–15. http://dx.doi.org/10.1007/s11148-020-00395-2.

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Li, Gong Fa, Si Qiang Xu, Guo Zhang Jiang, Ze Hao Wu, Jian Yi Kong, and Liang Xi Xie. "Influence of Working Lining Parameters on Stress Field of Ladle Composite Construction Body." Applied Mechanics and Materials 121-126 (October 2011): 800–804. http://dx.doi.org/10.4028/www.scientific.net/amm.121-126.800.

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The ladle is an important equipment of the metallurgical industry. Distribution of thermomechanical stress in linings has an essential influence on its life, and the size of its life-span influences the economic benefits of the iron and steel enterprise directly. Two-dimensional model of ladle based on law of finite element method is built, and the influence of thermal conductivity, thermal expansion coefficient, elasticity coefficient and thickness of work lining on ladle stress field are discussed. The calculation results indicate that stress increases with the increase of thermal conductivity, thermal expansion coefficient and elasticity coefficient and decrease of thickness.

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Wang, Xin, Guo Xiang Li, and Xuan Zhou. "The Technology of Ultrasound for Measuring the Thickness of the Pipe Lining." Applied Mechanics and Materials 457-458 (October 2013): 1176–80. http://dx.doi.org/10.4028/www.scientific.net/amm.457-458.1176.

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For the issue of the industrial pipe wall lining the thickness of dynamic changes difficult to be measured, based on the principle of ultrasonic thickness measurement and ultrasonic propagation in solids and based on existing research and theory of ultrasonic, this topic has designed a ultrasonic technology solution for measuring the thickness of the pipe wall lining. This technology achieves online measurement and non-destructive thickness measurement. Through processing and analysis of the experimental results, it demonstrates the feasibility and reliability of the technology. This technology has great significance for improving the security and stability of the pipeline.

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Hassani, Rahim, and Rouhollah Basirat. "Application of Hyperstatic Reaction Method for Designing of Tunnel Permanent Lining, Part I: 2D Numerical Modelling." Civil Engineering Journal 2, no. 6 (June 30, 2016): 244–53. http://dx.doi.org/10.28991/cej-2016-00000030.

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The increase of bored tunnels in the entire world has raised the question how to design the tunnel structure in an efficient way. This paper proposes a numerical approach to the Hyperstatic Reaction Method (HRM) for analysing permanent tunnel linings. The permanent tunnel lining is known as main structure of tunnel maintenance during the time. The HRM is one of the analysis methods for tunnel lining in long term. In this paper, two dimensional numerical modelling is performed by considering hyperstatic reaction concepts. Loading is done after the calculation of long term loads, and ground reaction is simulated by springs. Designing is done for Manjil-Rudabar freeway project, Tunnel No. 2. The numerical analyses were performed for Operational Design Earthquake (ODE) and Maximum Design Earthquake (MDE) loading conditions. A new simplified approach is used for considering the effect of earthquake loading on the tunnel lining. Then, an interaction diagram between axial force and bending moment used for investigating the capacity of tunnel lining. The thickness of tunnel lining and armature are calculated for three sections based on induced forces in tunnel lining. These forces were different in every section according to the load combinations, rock mechanics properties, lining properties, and overburden. The numerical results showed that the forces in tunnel lining for MDE condition is approximately 50% more than ODE condition in earthquake loading. This numerical processing presented that the HRM is a proper, fast, and practical method for designing and analysing the tunnel lining.

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Zhang, Sen, Zhihua Ren, Zude Ding, Jincheng Wen, and Zhixin Yan. "Influence of Existing Defects on Mechanical Properties of NC Lining." Advances in Materials Science and Engineering 2019 (December 19, 2019): 1–15. http://dx.doi.org/10.1155/2019/8571297.

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The mechanical properties of the lining are directly affected by defects such as voids behind the lining and insufficient thickness of the lining. In order to quantitatively evaluate this effect, the mechanical behavior of the lining under the influence of the void behind the lining, the insufficient thickness of the lining, and the combination of the two kinds of defects are adopted by the 1/5 scale model test. Based on the experimental research, numerical calculation models based on the CDP model for defect lining are established, with the effects of load direction, stratum stiffness, defect location, defect type, and degree on the mechanical behavior of the lining analyzed by the numerical simulation. The experimental and numerical results show that the void weakens the stiffness of the lining. As the void range increases, the lining becomes more deformable and its bearing capacity decreases with the “S” curve. Thinning significantly reduces the deformation properties of the lining and the bearing capacity and stiffness of the thinned section. The lining bearing capacity decreases linearly with the increase of the thinning ratio, when the load is applied at the thinning. With the influence of combined defects on the load-displacement curve of the lining fluctuating drastically, the mechanical properties of the lining are significantly reduced. The bearing capacity of lining decreases with the increase of composite defects in a “S” shape. The effect of void and lining thinning on the lining bearing capacity increases with the increase of the stiffness of the formation. The loss rate equation of the concrete lining bearing capacity under the influence of existing defects is established by using the L-M nonlinear regression analysis, a provision of scientific guidance for the safety evaluation of the defect lining.

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Antipkina, M. E., S. A. Krupennikov, and I. A. Levitsky. "Determining the optimum thickness of the lining of a heating furnace." NOVYE OGNEUPORY (NEW REFRACTORIES), no. 10 (January 23, 2020): 42–47. http://dx.doi.org/10.17073/1683-4518-2019-10-42-47.

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The problem of choosing the optimal thicknesses of the layers of refractory and heat-insulating materials that provide the minimum total cost of the lining and fuel used to compensate for heat losses is considered. The proposed technique (when specifying the required temperature at the boundary of the lining layers as an additional condition) reduces the problem of conditional two-dimensional optimization of the objective function, which does not have an unconditional minimum and has a break line, to the problem of finding the minimum of a unimodal one-dimensional objective function. The relevance of this work is due to the fact that during the overhaul of the furnace it is possible to replace its lining using new materials and optimize costs taking into account the updated state of the range of materials and their prices.

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Senthil, Kasilingam, Muskaan Sethi, and Loizos Pelecanos. "A review on the performance of the underground tunnels against blast loading." Journal of Structural Engineering & Applied Mechanics 4, no. 1 (March 30, 2021): 1–17. http://dx.doi.org/10.31462/jseam.2021.01001017.

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The tunneling system has become an important part of the present infrastructure system in all over the world. Therefore, it has become important to ensure the safety of the tunnels against any type of man-made blasting activities or other accidental blasting occurrence. In order to evaluate the performance of the tunnels against blast loading, a detailed review is carried out. Based on the review in the last couple of decades, the various parameters such as tunnel lining materials, tunnel shapes, tunnel lining thickness, tunnel burial depth, charge weight and standoff distance are high influences on the performance of underground tunnels against blast loading. It was observed that the tunnel roof and the tunnel wall center are most vulnerable to the blast loads. Also, it was found that more of the tunnel lining thickness results in lesser deformation at the tunnel roof and the tunnel wall center. The increase in the burial depth of the tunnel would reduce the extent of damage to the tunnel caused by effects of surface blast loading. The stiffness and strength of the ground media may be enhanced against the effects of blast loading by grouting measures. The studies revealed that the lining materials possessing blast waves absorbing properties can be best suited to be used in tunnel linings. Further, it was observed that more damage was caused to the tunnels due to the magnitude of the charge weight. An increase in the blast load causes a significant increase in the fracture area, residual stress and lateral displacement caused to the tunnel by the action of blast load. The standoff distance of the blast load from the tunnel also plays a significant role in the damage of the tunnel. More is the distance between the charge and the tunnel, lesser damage caused to the tunnels. In addition to that, the lining thickness was predicted and the trend was calibrated and fitted logarithmically with the available results. Based on the observation from the literature, it is concluded that the use of a single lining material in the tunnel against blast loading was studied predominantly in the couple of decades. Further, the performance of the tunnels in combination of different tunnel lining materials against blast loading was found limited. The influence of barriers to save the underground tunnels against blast loading was found limited.

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Xiao, Ming, and Chen Zhao. "Stability Analysis of Steel Lining at Pressure Diversion Tunnel Collapse Zone during Operating Period." Mathematical Problems in Engineering 2017 (2017): 1–14. http://dx.doi.org/10.1155/2017/3280414.

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At the collapse zone, the effects of the thickness of the consolidation grouting layer and the water pressure on the steel lining are vital to the stability of steel-lined pressure diversion tunnels. In this paper, a joint element and the load-sharing ratio of the consolidation layer are introduced to investigate the joint load-bearing characteristics of the steel lining and the consolidation layer and to determine a suitable consolidation layer thickness; a coupling method for simulating the hydromechanical interaction of the reinforced concrete lining is adopted to investigate the effect of internal water exosmosis on the seepage field at the collapse zone and to determine the external water pressure on the steel lining. In the case of a steel-lined pressure diversion tunnel, a numerical simulation is implemented to analyse the effect of the thickness of the consolidation layer and the distribution of the seepage field under the influence of internal water exosmosis. The results show that a 10 m thick consolidation layer and the adopted antiseepage measures ensure the stability of the steel lining at the collapse zone under internal and external water pressure. These research results provide a reference for the design of treatment measures for large-scale collapses in steel-lined pressure tunnels.

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Guo, Rui, and Chuan He. "Study on Selection of Segment Lining Structure for Large Profile Underwater Shield Tunnel." Applied Mechanics and Materials 353-356 (August 2013): 1359–63. http://dx.doi.org/10.4028/www.scientific.net/amm.353-356.1359.

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Based on Nanjing Yangtze River Tunnel project, the selection of segment lining of large profile underwater shield tunnel was analyzed. Considering from structure force, construction and economic, the comparison and selection for assembling modes, joint form, blocking modes, thickness and width of segment lining was carried out, The better segment lining structure was obtained. The study results can offer references for the design of segment lining of similar large profile underwater shield tunnel.

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Bastacky, J., C. Y. Lee, J. Goerke, H. Koushafar, D. Yager, L. Kenaga, T. P. Speed, Y. Chen, and J. A. Clements. "Alveolar lining layer is thin and continuous: low-temperature scanning electron microscopy of rat lung." Journal of Applied Physiology 79, no. 5 (November 1, 1995): 1615–28. http://dx.doi.org/10.1152/jappl.1995.79.5.1615.

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The low-temperature electron microscope, which preserves aqueous structures as solid water at liquid nitrogen temperature, was used to image the alveolar lining layer, including surfactant and its aqueous subphase, of air-filled lungs frozen in anesthetized rats at 15-cmH2O transpulmonary pressure. Lining layer thickness was measured on cross fractures of walls of the outermost subpleural alveoli that could be solidified with metal mirror cryofixation at rates sufficient to limit ice crystal growth to 10 nm and prevent appreciable water movement. The thickness of the liquid layer averaged 0.14 micron over relatively flat portions of the alveolar walls, 0.89 micron at the alveolar wall junctions, and 0.09 micron over the protruding features (9 rats, 20 walls, 16 junctions, and 146 areas), for an area-weighted average thickness of 0.2 micron. The alveolar lining layer appears continuous, submerging epithelial cell microvilli and intercellular junctional ridges; varies from a few nanometers to several micrometers in thickness, and serves to smooth the alveolar air-liquid interface in lungs inflated to zone 1 or 2 conditions.

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Ohmi, Tatsuya, and Manabu Iguchi. "Fabrication of Porous Intermetallic Thick Films by Metallic Powder-Liquid Reaction." Advances in Science and Technology 63 (October 2010): 370–73. http://dx.doi.org/10.4028/www.scientific.net/ast.63.370.

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We introduce the concept of functional microchannel lining. As an example, we describe the composition and structure of a Ni-Al intermetallic layer lining the inner wall of the microchannel produced by a powder-metallurgical process utilizing microscopic reactive infiltration and/or diffusion. The Ni-Al lining layer is a thick film consists of multiple sub-layers and has a peculiar porous structure, in which long and thin micropores had grown along the thickness direction of the film. In our experiment, a nickel-powder compact containing shaped aluminum wire was sintered at temperatures between the melting points of nickel and aluminum. Molten aluminum migrated into the surrounding nickel powder and reacted with nickel, and thus a microchannel and a Ni-Al intermetallic lining layer were produced. In this process, nickel powder composed the device body, and the aluminum wire gave the shape of the microchannel and act as the aluminum source for the lining layer. Metallographical examinations revealed that both aluminum concentration and voidage in the Ni-Al lining layer show a graded distribution along the thickness direction of the layer. Such a porous structure is appropriate for a catalyst support used for high-temperature reactions.

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Ning, Lichuan, Yuanmin Xie, and Ruyi Ma. "Fatigue Analysis of Ladle Shell and Prediction of Lining Thickness." IOP Conference Series: Materials Science and Engineering 631 (November 7, 2019): 022031. http://dx.doi.org/10.1088/1757-899x/631/2/022031.

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Ascari-Raccagni, A., and U. Baldari. "Turn-over lining flaps to repair full-thickness alar defects." Journal of the European Academy of Dermatology and Venereology 16, no. 4 (July 2002): 418–19. http://dx.doi.org/10.1046/j.1468-3083.2002.00570_6.x.

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Jankauskaitė, Virginija, Ada Gulbinienė, Alvydas Kondratas, Jurgita Domskienė, and Virginijus Urbelis. "Influence of the Structure of Footwear Upper and Lining Materials on Their Electrical Properties." Fibres and Textiles in Eastern Europe 26, no. 2(128) (April 30, 2018): 87–92. http://dx.doi.org/10.5604/01.3001.0011.5744.

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Protective footwear for occupational use conducts static electricity through the upper, linings, insole and outsole into the ground. Footwear must be made from appropriate material to reduce the possibility of electrocution and other electricity-related incidents. In this study the influence of footwear materials for the upper and lining components’ structure on their electrical properties was investigated. For investigations leather and various textile laminates were chosen. The thickness of leather coating, composition of textile laminates, the upper-lining system, and relative humidity of the environment on electrical resistivity changes were evaluated. Leather shows antistatic properties at standard humidity, but its electrical conductivity greatly increases at high humidity due to the presence of polar groups in the leather structure. Textile lining laminates composed of natural and synthetic fibres are insulators, but their systems with leather at high humidity show resistivity values close to antistatic materials. Leather acrylic coating decreases the electrical conductivity of materials.

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Zenga, Joseph, and John Chi. "Reconstruction of the Intranasal Lining." Facial Plastic Surgery 33, no. 01 (February 2017): 067–73. http://dx.doi.org/10.1055/s-0036-1597988.

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AbstractReconstruction of full-thickness nasal defects has been the subject of surgical inquiry and innovation for over 2,000 years. The replacement of the internal nasal lining is a critical feature of complex nasal reconstruction. Successful reconstruction can prevent cicatricial contraction, external distortion, and internal stenosis. An array of reconstructive possibilities has been described, including cutaneous, mucosal, and fascial options. The challenge to the reconstructive surgeon is to select the repair that maximizes internal stability, while maintaining a patent nasal airway, minimizing morbidity, and meeting patient expectations. This article reviews the options available for the reconstruction of the intranasal lining.

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Liang, Hua Qiang, and Jing Xi Wu. "Study on Restrain Effect of Ground Grouting to the Vertical Additional Force of Shaft Lining." Advanced Materials Research 594-597 (November 2012): 241–45. http://dx.doi.org/10.4028/www.scientific.net/amr.594-597.241.

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Based on the introduction of mechanism of ground grouting to reinforce shaft lining in detail, the paper analyzes the weakening effect of additional stress of shaft lining from ground grouting. According to the monitoring results of deformation of ground surface, shaft lining strain, and grouting curtain after grouting, the grouting activity makes the surface uplift of about50-80mm, shaft lining vertical strain release about 220με, mortar curtain average thickness near 8.2m, and the mechanical properties of soil are improved obviously.As a result of ground grouting effectively weaken the additional force has been accumulation for long time of shaft lining, and it can achieve the purpose of prevention and treatment the rupture of shaft lining. Ground grouting is a feasible means to control shaft lining.

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Hayashi, Naoya, Tatsuya Ohmi, and Manabu Iguchi. "Structure of Ni-Al Intermetallic Porous Thick Films Produced by Microscopic Reactive Infiltration." Materials Science Forum 631-632 (October 2009): 345–50. http://dx.doi.org/10.4028/www.scientific.net/msf.631-632.345.

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A microchanneling process utilizing microscopic reactive infiltration produces microchannels and alloy lining layers in metal bodies. We examined the composition and structure of a Ni-Al intermetallic lining layer with a peculiar porous structure produced by Ni-Al reactive infiltration. The Ni-Al lining layer is a thick film consists of multiple sub-layers and has many micropores. Such a porous structure and the heat resistance of Ni-Al intermetallic compound are appropriate for a catalyst support in high-temperature use. Image analysis and EPMA revealed that both aluminum concentration and voidage in the Ni-Al lining layer show a graded distribution along the thickness direction of the lining layer.

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Wang, Xing Hua, and Peng Tu. "Water Pressure Numerical Analysis of Lining Structure in Mountain Tunnel." Applied Mechanics and Materials 71-78 (July 2011): 4026–30. http://dx.doi.org/10.4028/www.scientific.net/amm.71-78.4026.

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It is hard to control the high pressure water in mountain tunnel construction. Distribution of seepage field, stress field and displacement field of tunnel are analyzed by numerical method with equivalent continuum model. And distribution rule of groundwater in rock, grouting circle and lining are also analyzed. The results of the study show that water pressure behind lining has a close relationship with rock, grouting circle, thickness of lining, permeability coefficient and drainage of tunnel.

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Niu, Ze Lin, and Zhan Ping Song. "Reliable Analysis and Study of Lining Structure of Tunnel in Loess Areas." Advanced Materials Research 368-373 (October 2011): 2642–45. http://dx.doi.org/10.4028/www.scientific.net/amr.368-373.2642.

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Safety and reliability of lining structure of tunnel affect the using of the tunnel. Inspection method Pearson is used, based on reliability mathematical knowledge, the article analyses the reliability of lining structure of tunnel and putts forward the regularity of distribution for the thickness of tunnel lining. At the same time, from the Angle of reducing the tunnel construction cost, the paper putts forward the method of saving the construction cost through mathematical statistics knowledge.

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Wang, Fang, Shao Hui He, Jun Liu, and Fa Lin Qi. "Application of Ground Penetrating Radar for Quality Detection of Tunnel Lining." Advanced Materials Research 503-504 (April 2012): 1655–59. http://dx.doi.org/10.4028/www.scientific.net/amr.503-504.1655.

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The Golmud-Lhasa section of Qinghai-Tibet railway is located in the plateau and permafrost region which tunnel lining produces serious diseases in the extremely bad environment. This paper states the application of Ground Penetrating Radar (GPR) for quality detection of tunnel lining and how to choose parameters, sit detection lines, analyze GPR cross section and classify lining diseases in filed investigation. The results suggest that non-destructive testing technology of GPR can be used to detect the tunnel lining diseases mainly including second lining thickness, cavities and backfilling imperfection zones, and the technology is effectively to detect tunnel lining in abominable surroundings. Furthermore, detection results can provide scientific basis to evaluate the tunnel’s safety performance and diseases degree objectively

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Sawczuk, Wojciech, Dariusz Ulbrich, Jakub Kowalczyk, and Agnieszka Merkisz-Guranowska. "Evaluation of Wear of Disc Brake Friction Linings and the Variability of the Friction Coefficient on the Basis of Vibroacoustic Signals." Sensors 21, no. 17 (September 3, 2021): 5927. http://dx.doi.org/10.3390/s21175927.

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The article presents the results of friction and vibroacoustic tests of a railway disc brake carried out on a brake stand. The vibration signal generated by the friction linings provides information on their wear and offers evaluation of the braking process, i.e., changes in the average friction coefficient. The algorithm presents simple regression linear and non-linear models for the thickness of the friction linings and the average coefficient of friction based on the effective value of vibration acceleration. The vibration acceleration signals were analyzed in the amplitude and frequency domains. In both cases, satisfactory values of the dynamics of changes above 6 dB were obtained. In the case of spectral analysis using a mid-band filter, more accurate models of the friction lining thickness and the average coefficient of friction were obtained. However, the spectral analysis does not allow the estimation of the lining thickness and the friction coefficient at low braking speeds, i.e., 50 and 80 km/h. The analysis of amplitudes leads to the determination of models in the entire braking speed range from 50 to 200 km/h, despite the lower accuracy compared to the model, based on the spectral analysis. The vibroacoustic literature presents methods of diagnosis of the wear of various machine elements such as bearings or friction linings, based on amplitude or frequency analysis of vibrations. These signal analysis methods have their limitations with regard to their scope of use and the accuracy of diagnosis. There are no cases of simultaneous use of different methods of analysis. This article presents the simultaneous application of the amplitude and frequency methods in the analysis of vibroacoustic signals generated by brake linings. Moreover, algorithms for assessing the wear of friction linings and the average coefficient of friction were presented. The algorithm enables determination of the time at which the friction linings should be replaced with new ones. The final algorithm analyzes the vibration acceleration signals using both amplitude analysis for low braking speeds, as well as spectral analysis for medium and high braking speeds.

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Zhao, Pengyu, Jianxun Chen, Yanbin Luo, Lijun Chen, Yao Li, and Chuanwu Wang. "Investigation of the Insulation Effect of Thermal Insulation Layer in the Seasonally Frozen Region Tunnel: A Case Study in the Zuomutai Tunnel, China." Advances in Civil Engineering 2019 (September 30, 2019): 1–14. http://dx.doi.org/10.1155/2019/4978359.

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In this study, a field temperature test was performed to reveal the insulation effect of the thermal insulation layer installed at lining surface. The thermal insulation layer is made of polyphenolic, and the thickness is 7 cm. According to the test results, the temperature of the thermal insulation layer and lining continuously changes with the air temperature in the tunnel in an approximately trigonometric function. The temperature of tunnel lining without thermal insulation layer is close to the air temperature, which results in the lining frost in winter. The maximum temperature difference between the two sides of the thermal insulation layer can be 27°C. In the section whose buried depth is more than 11.4 m, the temperature of lining with thermal insulation layer in winter is mainly influenced by the cold air in the tunnel. When the monthly mean and lowest daily mean air temperature are lower than −10°C and −14.3°C in the coldest month, the temperature at the inner side of the thermal insulation layer is below 0°C. When the buried depth is less than 11.4 m, the temperature of lining is also influenced by the low temperature at ground surface. The temperature of lining is lower. The thicker thermal insulation layer and even active heat measure are needed. Therefore, the design of thermal insulation layer thickness should consider the air temperature distribution and tunnel buried depth along the tunnel length.

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Li, Li Xin, Shuang Zhang, Qi Yun Zou, and Qing Xue Shi. "Shield Lining Segments Design Research Based on Characteristic Parameters." Applied Mechanics and Materials 470 (December 2013): 437–40. http://dx.doi.org/10.4028/www.scientific.net/amm.470.437.

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As we all know, the thickness of the shield lining segments, reinforcement ratio and other parameters of the design have a direct impact on the economics of the project. We have taken a model of parametric analysis simulation and by the way of changing the parameter of lining segments to research their deformation and stress. Finally, we get the relationship between the characteristic parameters and the deformation and stress of the lining segments, and summed up the characteristic parameters which are more influential.

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Fan, Kaixiang, Yusheng Shen, Shuaishuai Wang, Bo Gao, Qing Zheng, Gaoming Yan, and Peng Min. "Dynamic Response of Composite Lining Tunnel with Buffer Layer: An Analytical and Experimental Investigation." Mathematical Problems in Engineering 2020 (November 22, 2020): 1–17. http://dx.doi.org/10.1155/2020/5453138.

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Composite lining is often designed for the mountainous tunnels in high-intensity earthquake areas. The application of the buffer layer will bring more advantages, while the shock-absorbing mechanism is still unclear currently. In this paper, based on the Fourier-Bessel series expansion method, the dynamic stress concentration factor of composite lining tunnel with buffer layer subjected to plane SV waves in the half-space is obtained. Then, the influence of geometric and mechanical parameters of the buffer layer on composite lining was systematically analyzed. Finally, the correctness of the analytical solutions is verified by series shaking table tests and numerical simulations. Results suggest that the buffer layer can play the role of “redistributing” the seismic load, and it can effectively reduce the dynamic responses of secondary lining but amplify in primary support. There is an optimal interval of the stiffness and thickness for the buffer layer. When the stiffness ratio of the buffer layer to surrounding rock is 1/10 ∼ 1/50 or the ratio of buffer layer thickness to inner diameters of secondary lining is 1/40 ∼ 1/20, the shock-absorbing performance is remarkable. The general damage observations in tests show that the crown, arch springing, and invert of composite lining in case of no buffer layer are prone to cracking under a strong earthquake. The invert of the composite lining is more susceptible to be damaged after adopting the buffer layer. In general, the analytical results were consistent with experimental and numerical results. The above study results may provide theoretical support and experimental data for the seismic design of composite lining tunnels.

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Qi, Hui, Yang Zhang, Jing Guo, Fuqing Chu, and Mehmet Serkan Kirgiz. "Dynamic Stress Analysis of a Circular-Lined Tunnel in Composite Strata-SH Wave Incidence." Advances in Civil Engineering 2020 (September 29, 2020): 1–13. http://dx.doi.org/10.1155/2020/8827737.

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It is necessary to study the problem of seismic wave scattering in composite stratum for tunnel engineering because the existence of composite strata will make the stress of tunnels more complicated during earthquakes. In this thesis, a series solution of the scattering wave field of the composite strata and lining is obtained using the complex function method. According to the stress and displacement boundary conditions between the composite stratum and the lining, a series of equations are established and are solved by means of Fourier transformation and finite term truncation, and the calculation errors are also discussed. Through programming calculations, the dynamic stress concentration factor (DSCF) of circular tunnels in the two types of composite strata, “hard-over-soft” and “soft-over-hard,” is analyzed when SH waves propagate, and certain conclusions on the scattering of SH waves that are distinguished from the case of single homogeneous layers are reached. The research in this article reveals some phenomena. For the Q345 steel lining in the calculation examples, it is found in this paper that increasing the thickness of the lining is effective to reduce the influence of the DSCF. But, for C30 concrete, increasing the thickness of the lining reduces the DSCF of the outer surface while increasing the DSCF of the inner surface.

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Heimo, Juhani, Ari Jokilaakso, Marko Kekkonen, Merete Tangstad, and Anne Støre. "Thermal conductivity of titanium slags." Metallurgical Research & Technology 116, no. 6 (2019): 635. http://dx.doi.org/10.1051/metal/2019064.

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In ilmenite smelting furnaces, a freeze lining of solidified slag is used to protect the furnace refractories against the aggressive titanium slag. Freeze lining thickness cannot be measured directly due to harshness of conditions inside the process, thus process modelling is required. Several parameters influence the thickness of the freeze-lining, one of them being thermal conductivity of the frozen slag. However, there is a lack of thermal conductivity values for high titanium slags −especially as a function of temperature. In this study, thermal conductivity of three titanium slag samples and an additional sample of freeze-lining was measured from room temperature to 1100/1400 °C with the laser flash analysis method. In addition, thermal expansion and microstructures of the samples were studied to provide an extensive understanding of how microstructure will affect thermal conductivity. The thermal conductivity of the slag samples was found to increase from 1.2 to a maximum of 2.4 W/(m K) when increasing temperature from room temperature to 1100 °C. An additional experiment at 1400 °C showed that the thermal conductivity increased further as the temperature increased. The freeze-lining sample behaves differently, with conductivity being the highest at room temperature, 2.2 W/(m K).

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42

Jiang, Xinghong, and Ke Li. "Analysis and Safety Assessment of Lining Thickness Defects in Highway Tunnels." IOP Conference Series: Materials Science and Engineering 741 (March 24, 2020): 012079. http://dx.doi.org/10.1088/1757-899x/741/1/012079.

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43

Zhang, Jing Jing, Jun Deng, Kai Zhang, and Cheng Huang. "Comparative Study on Calculation Model of Hydraulic Tunnel Lining Structure between Beam Element and Solid Element." Applied Mechanics and Materials 405-408 (September 2013): 1340–45. http://dx.doi.org/10.4028/www.scientific.net/amm.405-408.1340.

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According to the standard Specification for Design of Hydraulic Tunnels (DL/T 5195-2004), the free-flow tunnel lining structure should be calculated with beam element of finite element method that based on structural mechanics. However, the practical calculation shows that when the lining structure reaches a certain thickness, the beam element calculation results are no longer accurate. Combining with the engineering example, stress and internal force of lining structure with different thickness were calculated by using beam3 beam element and the solid65 element respectively in frame beam analysis. Differences analysis shows that the solid element is better than beam element in calculation. The influence of solid elements grid size on the result accuracy was conducted, and used to amend the calculation result of the solid element, which provides a certain reference on choosing the right element in the similar projects or structure simulation.

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44

Ge, Yao, Ying Li, Han Wei, Hao Nie, Weitian Ding, Yi Cao, and Yaowei Yu. "A Novel Approach for Measuring the Thickness of Refractory of Metallurgical Vessels." Materials 13, no. 24 (December 10, 2020): 5645. http://dx.doi.org/10.3390/ma13245645.

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The advancement of metallurgical vessels, such as blast furnaces, shaft furnaces, and torpedo ladles, can be better controlled and expanded for a greater lifespan if the thickness of the refractory lining wear is known and predicted. In the past, various methods including radioactive tracers, infrared (IR) thermography, electromagnetic waves, ultrasonic tomography, and temperature field have been tested to determine the thickness of the refractory wall. However, for various reasons, these methods have failed to be effective. This paper presents a novel method—electromotive force (EMF)—for predicting the thickness of refractory lining wear in vessels, including a small-scale vessel in the laboratory, an industrial torpedo ladle, and in the two refining hearths of blast furnaces. The experimental results show that the magnitude of the EMF signal increases with a decrease in wall thickness. Prediction values of the refractory wall thickness are consistent with measured ones. The relative error of EMF measurement for the torpedo ladle is around 6.8%. The EMF measurement of blast furnace hearths is quite accurate, and the relative error is less than 11%.

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45

Pan, Ji Shun, Lei Yang, Yuan Bao Leng, and Zhi Quan Lv. "Application of the Ground Penetrating Radar in the Quality Detection of Tunnel Lining." Advanced Materials Research 243-249 (May 2011): 5381–85. http://dx.doi.org/10.4028/www.scientific.net/amr.243-249.5381.

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Based on the ground penetrating radar's work mechanism, this article briefly introduces the working principle and the data processing method of ground penetrating radar detecting the tunnel lining. In view of the lining quality detection's characteristics, it summarizes a series of atlas reflection characteristic of the examination target such as the lining thickness, the backfill quality, the steel bar reinforcement situation, the adjacent formation structural feature and so on, and analyses and comments on them with project examples. The research believes that under appropriate working condition, as an important means to guarantee the construction security and maintain the tunnel health, ground penetrating radar technology can examine the lining quality fast and effectively, and meet the needs of the tunnel lining quality detection with suitable equipment, working method and data processing plan.

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46

Khoirudin, Khoirudin. "OPTIMASI DESAIN PADA DINDING FURNACE DENGAN TEMPERATUR KERJA 1000 C." JURNAL KAJIAN TEKNIK MESIN 3, no. 1 (May 29, 2019): 1–8. http://dx.doi.org/10.52447/jktm.v3i1.1054.

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The aims of this research is to study and analysis on furnace walls with variation of hot face lining material types, variation of refractory material types, and variation of thickness of insulating materials to outer wall temperature at furnace with working temperature 1000 oC. This research uses a variety of hot face lining material in the form of ceramic fiber blanket with CR1260, CR1400, and CR1430, variations of refractory material in the form of refractory brick with the type NJM-20, NJM-23, and NJM-26, and using ROCKWOOL as an insulating material with a thickness variation of 50 mm, 75 mm, 100 mm. This research was simulated using Steady State Thermal ANSYS Mechanical (ANSYS Multiphysic) software. The result of the research shows the difference of the outer wall temperature value of the furnace. The highest wall temperature is in interaction with the wall without insulation, hot face lining material using CR1260, and NJM-26 as refractory material is 75.211 oC. While the lowest wall temperature is in the interaction of 100 mm thick insulation, hot face lining material using CR1430, NJM-20 as refractory material is 46.682 oC.

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Lai, Jin Xing, Guang Long Zhang, and Xiao Wei Liu. "A Case Study of Distress Detection and Treatment of Loess Road Tunnel." Key Engineering Materials 474-476 (April 2011): 1787–91. http://dx.doi.org/10.4028/www.scientific.net/kem.474-476.1787.

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Based on the characteristic of distress in Qijia mountain road tunnel, thickness, cavity distribution, crevice water were detected with geo-radar. Material of lining was nondestructive detected with sound locater. Limiting structure of the tunnel was detected with circumscription apparatus. Based on detected results cause of the distress was analyzed. Three treatment schemes were put forward by slurry injection from the back of lining structure, reinforcement lining, treating the water proof system. Stability of surrounding rock and the state of forces of the lining structure were analyzed before and after treatment. It is showed that the treatment scheme of the tunnel is feasible. Taken construction and cost estimate into account, optimal scheme is obtained.

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Gostian, PD Dr med Antoniu-Oreste, Dr med Matthias Balk, Dr med Achim Stegmann, Prof Dr med Dr h. c. Heinrich Iro, and Prof Dr med Jochen Wurm. "Full-Thickness Skin Grafts and Quilting Sutures for the Reconstruction of Internal Nasal Lining." Facial Plastic Surgery 36, no. 03 (June 2020): 297–304. http://dx.doi.org/10.1055/s-0040-1713116.

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AbstractRestoration of the inner nasal lining is an essential factor in successful nasal reconstruction. Among various methods, free full-thickness skin grafting represents a readily available and feasible technique. A prerequisite for success is a secure and immobile fixation to the undersurface of the nourishing forehead flap. This retrospective study aims to evaluate the results of multiple quilting sutures to secure free full-thickness skin grafts for the reconstruction of the inner nasal lining in partial and extended nasal reconstruction. Between February 1, 2015, and December 31 2018, 16 patients underwent three-stage nasal reconstruction of all three layers using a forehead flap. All full-thickness free flaps were harvested from either the neck or inguinal area and fixated to the undersurface of the distal part of the forehead flap by multiple quilting sutures. All but one free skin grafts healed well (seven ♀; mean: 63 years; range: 52–81). Four patients developed minor complications that resolved completely through conservative treatment. One patient with a history of stroke, extensive nicotine abuse, and arterial hypertension developed flap necrosis that required two surgical revisions and ended up with a stenosis of the left nostril. The follow-up time averaged 18.4 months (range: 3–55 months). Multiple quilting sutures are an effective and feasible option to fixate full-thickness free skin grafts on the undersurface of the forehead flap for the reconstruction of the inner nasal lining. They are not associated with increased risks for necrosis and can be applied even to extended full-thickness nasal defects in selected cases.

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Huang, Yubing, Bei Jiang, Yukun Ma, Huayong Wei, Jincheng Zang, and Xiang Gao. "Study on Asymmetric Failure and Control Measures of Lining in Deep Large Section Chamber." Energies 14, no. 14 (July 6, 2021): 4075. http://dx.doi.org/10.3390/en14144075.

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Lining is often used as the last line of defense in deep large section chamber. Under the asymmetric load, it is easy to damage, resulting in the overall repair of the chamber. Aiming at this problem, taking the pump house in Wanfu Coal Mine under construction in China as an engineering example, we analyzed the asymmetric failure of pump house lining caused by construction disturbance, established the lining mechanical model and quantitative evaluation indexes, such as bending moment change rate, bending moment balance rate, displacement change rate and displacement balance rate, studied the influence mechanism of asymmetrical coefficient, section size and lining thickness on the mechanical behavior of lining, and proposed the control measures of deep large section chamber with the core of “strengthening asymmetric support, reducing section size and improving lining strength”. The field monitoring shows that the asymmetric deformation of the pump house is effectively controlled, and the maximum displacement is only 7.3 mm, which ensures the long-term stability of the chamber.

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Liu, Gang. "Numerical Calculation and Analysis of Water-Lubricated Stern Bearing Considering Elastic Hydrodynamic." Advanced Materials Research 1061-1062 (December 2014): 653–57. http://dx.doi.org/10.4028/www.scientific.net/amr.1061-1062.653.

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The deformation of marine water-lubricated stern bearing which the lining materials are polymer materials is much bigger than the bearing built with metal materials. So, in order to improve the calculate accuracy of elastic hydrodynamic, it is necessary to consider the deformation of the lining. Both pressure and thickness distributions of water film which contrasts with the hydrodynamic lubrication are presented by the Reynolds equation, and combining with the elastic deformation of the stern bearing solved by using the finite element method theory. The result shows that the stern bearing water film pressure of elastic hydrodynamic lubrication is lower than that of hydrodynamic lubrication, while the water film thickness is larger.

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Journal articles on the topic 'Lining Thickness'

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