The Experts below are selected from a list of 5064 Experts worldwide ranked by ideXlab platform

S. Kumar - One of the best experts on this subject based on the ideXlab platform.

  • on axisymmetric adhesive joints with graded interface stiffness
    International Journal of Adhesion and Adhesives, 2013
    Co-Authors: S. Kumar, James Scanlan
    Abstract:

    Abstract An improved analytical model is presented for the stress analysis of interface stiffness graded axisymmetric adhesive joints. The governing integro-differential equation of the problem is obtained through a variational method which minimizes the complementary energy of the bonded assembly. The joint is composed of similar or dissimilar polar anisotropic and/or isotropic adherends and a functionally modulus graded bondline (FMGB) adhesive. The elastic modulus of the adhesive is functionally graded along the bondlength by assuming smooth modulus profiles which reflect the behavior of practically producible graded bondline. Influence of non-zero radial stresses in the bonded system on shear and normal stresses is evaluated. The stress distribution predicted by this refined model is compared with that of mono-modulus bondline (MMB) model for the same Axial Tensile Load in order to estimate reduction in shear and normal stress peaks in the bondline and the adherends. A systematic parametric study indicates that an optimum joint strength can be achieved by employing a stiffness graded bondline with an appropriate combination of geometrical and material properties of the adherends. This model can also be applied to examine the effects of loss of interface stiffness due to an existing defect and/or damage in the bondline.

  • analysis of tubular adhesive joints with a functionally modulus graded bondline subjected to Axial Loads
    International Journal of Adhesion and Adhesives, 2009
    Co-Authors: S. Kumar
    Abstract:

    The strength and lifetime of adhesively bonded joints can be significantly improved by reducing the stress concentration at the ends of overlap and distributing the stresses uniformly over the entire bondline. The ideal way of achieving this is by employing a modulus graded bondline adhesive. This study presents a theoretical framework for the stress analysis of adhesively bonded tubular lap joint based on a variational principle which minimizes the complementary energy of the bonded system. The joint consists of similar or dissimilar adherends and a functionally modulus graded bondline (FMGB) adhesive. The varying modulus of the adhesive along the bondlength is expressed by suitable functions which are smooth and continuous. The axisymmetric elastic analysis reveals that the peel and shear stress peaks in the FMGB are much smaller and the stress distribution is more uniform along its length than those of mono-modulus bondline (MMB) adhesive joints under the same Axial Tensile Load. A parametric evaluation has been conducted by varying the material and geometric properties of the joint in order to study their effect on stress distribution in the bondline. Furthermore, the results suggest that the peel and shear strengths can be optimized by spatially controlling the modulus of the adhesive.

Runshaug Alexander - One of the best experts on this subject based on the ideXlab platform.

  • Eksperimentell undersøkelse av rissavstand
    'Saint Louis University', 2021
    Co-Authors: Litlekalsøy, Jarle Smeland, Runshaug Alexander
    Abstract:

    Cracks in concrete structures have an effect on both the durability and the visuals of the structure. Therefore, it is important to control the cracks in reinforced concrete structures. This thesis address the difference in concrete cover thickness and how it affects the crack spacing and width. The concrete cover thickness is an important parameter when calculating the crack spacing and width of a reinforced concrete structure. From the Eurocode 2 and the Model Code 2010 the concrete cover is very deciding when calculating the crack spacing and width. This thesis compares the results from an experiment consisting of three different cover thicknesses against the results using the calculations from the current standards. Earlier studies suggests that the formulations in the current standards regarding the crack spacing and the crack width are questionable. The experiment for this thesis contained of testing six reinforced concrete specimens by applying Axial Tensile Load

  • Eksperimentell undersøkelse av rissavstand
    'Saint Louis University', 2021
    Co-Authors: Runshaug Alexander, Litlekalsøy Jarle
    Abstract:

    Cracks in concrete structures have an effect on both the durability and the visuals of the structure. Therefore, it is important to control the cracks in reinforced concrete structures. This thesis address the difference in concrete cover thickness and how it affects the crack spacing and width. The concrete cover thickness is an important parameter when calculating the crack spacing and width of a reinforced concrete structure. From the Eurocode 2 and the Model Code 2010 the concrete cover is very deciding when calculating the crack spacing and width. This thesis compares the results from an experiment consisting of three different cover thicknesses against the results using the calculations from the current standards. Earlier studies suggests that the formulations in the current standards regarding the crack spacing and the crack width are questionable. The experiment for this thesis contained of testing six reinforced concrete specimens by applying Axial Tensile Load.Cracks in concrete structures have an effect on both the durability and the visuals of the structure. Therefore, it is important to control the cracks in reinforced concrete structures. This thesis address the difference in concrete cover thickness and how it affects the crack spacing and width. The concrete cover thickness is an important parameter when calculating the crack spacing and width of a reinforced concrete structure. From the Eurocode 2 and the Model Code 2010 the concrete cover is very deciding when calculating the crack spacing and width. This thesis compares the results from an experiment consisting of three different cover thicknesses against the results using the calculations from the current standards. Earlier studies suggests that the formulations in the current standards regarding the crack spacing and the crack width are questionable. The experiment for this thesis contained of testing six reinforced concrete specimens by applying Axial Tensile Load

Deping Zhang - One of the best experts on this subject based on the ideXlab platform.

  • Effects of corrosion defect and Tensile Load on injection pipe burst in CO2 flooding.
    Journal of Hazardous Materials, 2019
    Co-Authors: Zhenyi Liu, Yao Zhao, Yi Zhou, Ping Huang, Li Xuan, Xue Wang, Deping Zhang
    Abstract:

    Abstract Highly pressurized injection pipelines in CO2 flooding often suffer from different types of corrosion defects and mechanical stresses and can easily cause serious damage to the environment. Currently, the descending rule of pipe burst pressures under different defect parameters and Tensile Loads has not been studied systematically. In this study, a section of injection pipe was used to simulate the burst process of pipe with groove and general corrosion defects. The crack appearance showed that the fracture began at the centre of the longitudinal defect line as an instantaneous ductile rupture and then extended along both sides as a rapid brittle rupture under high stress. The burst pressure in the groove corrosion defect tests showed that the defect depth played a more dominant role in pipe burst than the defect length did, and when a 30 MPa Axial Tensile Load was added, the pipe burst pressure was reduced approximately 20–30%. In general corrosion defect tests, the burst pressures were generally much lower than the groove corrosion defect tests produced, and when adding the Axial Tensile Load, the burst mode changed. Moreover, the value of the burst pressure can be a sign of BLEVE (boiling liquid expanding vapor explosion) severity.

Chen Yuping - One of the best experts on this subject based on the ideXlab platform.

  • application of stiffness models of classical laminate plate theory in plywood
    Journal of Nanjing Forestry University, 2007
    Co-Authors: Chen Yuping
    Abstract:

    Based on the structure characteristic of plywood and former predictions of in-plane modulus of poplar veneer,the stiffness models of classical laminate plate theory were applied to plywood.In the models test,two plies impregnated paper were orthotropicly overlaided on the face and back poplar veneer.When the test specimens were under single Axial Tensile Load or pure bending moment Load,the strain of face and back plies,ex and ey was obtained through strain gage.The experimental and theoretic value of some compliance coefficients were tested.The results showed that the stiffness models could predict the stiffness of plywood well,and the stiffness models of classical laminate plate theory could be used to describe the stiffness of plywood.

Wei Linghong. - One of the best experts on this subject based on the ideXlab platform.

  • Experimental and finite element analysis for adhesive bonded joints
    2003
    Co-Authors: Wei Linghong.
    Abstract:

    This project presented the analysis of the shear stress distribution experienced at the bondline of the adhesive bonded splice joints subjected to Axial Tensile Load on the ends of substrates. Two joint configurations were considered, namely “Normal Doubler” joint and “Stepped Doubler” joint. A uni-Axial tension test was carried out as a study on the shear stress distribution at the bondline of the adhesive bonded joints. A finite element analysis was conducted to simulate the specimen behavior using Finite Element Software ANSYS and the results were verified by a series of experiments.Master of Science (Mechanics & Processing of Materials