The Experts below are selected from a list of 33051 Experts worldwide ranked by ideXlab platform
Dipan Bose - One of the best experts on this subject based on the ideXlab platform.
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the tolerance of the femoral shaft in combined Axial Compression and bending loading
Stapp car crash journal, 2009Co-Authors: Johan B Ivarsson, Daniel Genovese, James R Bolton, Jeffrey Richard Crandall, Costin D Untaroiu, Dipan BoseAbstract:The likelihood of a front seat occupant sustaining a femoral shaft fracture in a frontal crash has traditionally been assessed by an injury criterion relying solely on the Axial force in the femur. However, recently published analyses of real world data indicate that femoral shaft fracture occurs at Axial loads levels below those found experimentally. One hypothesis attempting to explain this discrepancy suggests that femoral shaft fracture tends to occur as a result of combined Axial Compression and applied bending. The current study aims to evaluate this hypothesis by investigating how these two loading components interact. Femoral shafts harvested from human cadavers were loaded to failure in Axial Compression, sagittal plane bending, and combined Axial Compression and sagittal plane bending. All specimens subjected to bending and combined loading fractured midshaft, whereas the specimens loaded in Axial Compression demonstrated a variety of failure locations including midshaft and distal end. The interaction between the recorded levels of applied moment and Axial Compression force at fracture were evaluated using two different analysis methods: fitting of an analytical model to the experimental data and multiple regression analysis. The two analysis methods yielded very similar relationships between applied moment and Axial Compression force at midshaft fracture. The results indicate that posteroanterior bending reduces the tolerance of the femoral shaft to Axial Compression and that that this type of combined loading therefore may contribute to the high prevalence of femoral shaft fracture in frontal crashes. Language: en
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the tolerance of the femoral shaft in combined Axial Compression and bending loading
Stapp car crash journal, 2009Co-Authors: Johan Ivarsson, Daniel Genovese, James R Bolton, Jeffrey Richard Crandall, Costin D Untaroiu, Dipan BoseAbstract:The likelihood of a front seat occupant sustaining a femoral shaft fracture in a frontal crash has traditionally been assessed by an injury criterion relying solely on the Axial force in the femur. However, recently published analyses of real world data indicate that femoral shaft fracture occurs at Axial loads levels below those found experimentally. One hypothesis attempting to explain this discrepancy suggests that femoral shaft fracture tends to occur as a result of combined Axial Compression and applied bending. The current study aims to evaluate this hypothesis by investigating how these two loading components interact. Femoral shafts harvested from human cadavers were loaded to failure in Axial Compression, sagittal plane bending, and combined Axial Compression and sagittal plane bending. All specimens subjected to bending and combined loading fractured midshaft, whereas the specimens loaded in Axial Compression demonstrated a variety of failure locations including midshaft and distal end. The interaction between the recorded levels of applied moment and Axial Compression force at fracture were evaluated using two different analysis methods: fitting of an analytical model to the experimental data and multiple regression analysis. The two analysis methods yielded very similar relationships between applied moment and Axial Compression force at midshaft fracture. The results indicate that posteroanterior bending reduces the tolerance of the femoral shaft to Axial Compression and that that this type of combined loading therefore may contribute to the high prevalence of femoral shaft fracture in frontal crashes.
Jin Zhang - One of the best experts on this subject based on the ideXlab platform.
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behavior of innovative circular ice filled steel tubular stub columns under Axial Compression
Construction and Building Materials, 2018Co-Authors: Yanlei Wang, Guipeng Chen, Baolin Wan, Hao Lin, Jin ZhangAbstract:Abstract The use of conventional building materials has many limitations in cold regions. Inspired by the idea of concrete filled steel tube (CFT), a new form of construction component named ice filled steel tube (IFT), which effectively combines the advantages of both ice and steel tube, was innovatively proposed in this study. This paper presents an experimental study on circular IFT stub columns under Axial Compression. The main parameter of the test specimens is the diameter-to-thickness (D/t) ratio of the steel tube. A total of 12 specimens including 3 plain ice columns and 9 circular IFT columns were divided into four series and tested under Axial Compression. The test results showed that the development of cracks in ice was delayed by the steel tube. As a result, both the ultimate bearing capacity and the ductility of the ice column were improved due to the confinement from the steel tube. The local bucking at the bottom of the steel tube was also delayed by the ice core. Therefore, the circular IFT column has good potential to serve as a structural component in cold regions.
Azam Tafreshi - One of the best experts on this subject based on the ideXlab platform.
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instability of delaminated composite cylindrical shells under combined Axial Compression and bending
Composite Structures, 2008Co-Authors: Azam TafreshiAbstract:Abstract Composite cylindrical shells and panels are widely used in aerospace structures. These are often subjected to defects and damage from both in-service and manufacturing events. Delamination is the most important of these defects. This paper deals with the instability analysis of delaminated composite cylindrical shells subject to pure bending and also combined bending and Axial Compression, using the finite element method. The combined double-layer and single-layer of shell elements are employed, which in comparison with the three-dimensional finite elements requires less computing time and space for the same level of accuracy. The effect of contact in the buckling mode has been considered, by employing contact elements between the delaminated layers. The interactive buckling curves and postbuckling response of delaminated cylindrical shells have been obtained. In the analysis of post-buckled delaminations, a study using the virtual crack closure technique has been performed to find the distribution of the strain energy release rate along the delamination front. The results show that under pure bending, laminated cylindrical shells are more sensitive to the presence of delamination, than they are under pure Axial Compression. It was also observed that the effects of delamination are more apparent when the composite cylindrical shells are subjected to combined Axial Compression and bending. In this case, with a slight increase of the applied bending moment, the strain energy release rate distribution on the compressive side of the cylinder changes drastically.
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delamination buckling and postbuckling in composite cylindrical shells under combined Axial Compression and external pressure
Composite Structures, 2006Co-Authors: Azam TafreshiAbstract:A series of finite element analyses on the delaminated composite cylindrical shells subject to combined Axial Compression and pressure are carried out varying the delamination thickness and length, material properties and stacking sequence. Based on the FE results, the characteristics of the buckling and postbuckling behaviour of delaminated composite cylindrical shells are investigated. The combined double-layer and single-layer of shell elements are employed which in comparison with the three-dimensional finite elements requires less computing time and space for the same level of accuracy. The effect of contact in the buckling mode has been considered, by employing contact elements between the delaminated layers. The interactive buckling curves and postbuckling response of delaminated cylindrical shells have been obtained. In the analysis of post-buckled delaminations, a study using the virtual crack closure technique has been performed to find the distribution of the local strain energy release rate along the delamination front. The results are compared with the previous results obtained by the author on the buckling and postbuckling of delaminated composite cylindrical shells under the Axial Compression and external pressure, applied individually.
H.-k. Yang - One of the best experts on this subject based on the ideXlab platform.
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Stability of multi-walled carbon nanotubes under combined bending and Axial Compression loading
Nanotechnology, 2006Co-Authors: Xiaodong Wang, Bo Sun, H.-k. YangAbstract:This paper reports the results of an investigation into the stability of an individual multi-walled carbon nanotube subjected to combined bending and Axial Compression loading. The effect of van der Waals forces between two adjacent tubes is taken into account and a multiple-shell model is adopted. According to the ratio of radius to thickness, multi-wall carbon nanotubes discussed here are classified into three cases: thin, thick, and nearly solid. The critical combined loading and the stability mode are calculated for various ratios of radius to thickness. Results carried out show that the stability mode corresponding to the critical combined loading is unique, which is obviously different from the purely Axial Compression buckling of an individual multi-wall carbon nanotube. It is also seen from numerical examples that the distribution of the maximum critical bending stresses applied oil each tube of MWNTS under combined bending and Axial Compression loading is dependent on the ratio of radius to thickness and the ratio of Axial Compression loading to bending moment. The new features of the combined stability of multi-walled carbon nanotubes Under combined bending and Axial Compression loading and some meaningful and interesting results in this paper are helpful for the application and the design of nanostructures in which multi-wall carbon nanotubes act as basic elements.
Jeffrey Richard Crandall - One of the best experts on this subject based on the ideXlab platform.
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the tolerance of the femoral shaft in combined Axial Compression and bending loading
Stapp car crash journal, 2009Co-Authors: Johan B Ivarsson, Daniel Genovese, James R Bolton, Jeffrey Richard Crandall, Costin D Untaroiu, Dipan BoseAbstract:The likelihood of a front seat occupant sustaining a femoral shaft fracture in a frontal crash has traditionally been assessed by an injury criterion relying solely on the Axial force in the femur. However, recently published analyses of real world data indicate that femoral shaft fracture occurs at Axial loads levels below those found experimentally. One hypothesis attempting to explain this discrepancy suggests that femoral shaft fracture tends to occur as a result of combined Axial Compression and applied bending. The current study aims to evaluate this hypothesis by investigating how these two loading components interact. Femoral shafts harvested from human cadavers were loaded to failure in Axial Compression, sagittal plane bending, and combined Axial Compression and sagittal plane bending. All specimens subjected to bending and combined loading fractured midshaft, whereas the specimens loaded in Axial Compression demonstrated a variety of failure locations including midshaft and distal end. The interaction between the recorded levels of applied moment and Axial Compression force at fracture were evaluated using two different analysis methods: fitting of an analytical model to the experimental data and multiple regression analysis. The two analysis methods yielded very similar relationships between applied moment and Axial Compression force at midshaft fracture. The results indicate that posteroanterior bending reduces the tolerance of the femoral shaft to Axial Compression and that that this type of combined loading therefore may contribute to the high prevalence of femoral shaft fracture in frontal crashes. Language: en
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the tolerance of the femoral shaft in combined Axial Compression and bending loading
Stapp car crash journal, 2009Co-Authors: Johan Ivarsson, Daniel Genovese, James R Bolton, Jeffrey Richard Crandall, Costin D Untaroiu, Dipan BoseAbstract:The likelihood of a front seat occupant sustaining a femoral shaft fracture in a frontal crash has traditionally been assessed by an injury criterion relying solely on the Axial force in the femur. However, recently published analyses of real world data indicate that femoral shaft fracture occurs at Axial loads levels below those found experimentally. One hypothesis attempting to explain this discrepancy suggests that femoral shaft fracture tends to occur as a result of combined Axial Compression and applied bending. The current study aims to evaluate this hypothesis by investigating how these two loading components interact. Femoral shafts harvested from human cadavers were loaded to failure in Axial Compression, sagittal plane bending, and combined Axial Compression and sagittal plane bending. All specimens subjected to bending and combined loading fractured midshaft, whereas the specimens loaded in Axial Compression demonstrated a variety of failure locations including midshaft and distal end. The interaction between the recorded levels of applied moment and Axial Compression force at fracture were evaluated using two different analysis methods: fitting of an analytical model to the experimental data and multiple regression analysis. The two analysis methods yielded very similar relationships between applied moment and Axial Compression force at midshaft fracture. The results indicate that posteroanterior bending reduces the tolerance of the femoral shaft to Axial Compression and that that this type of combined loading therefore may contribute to the high prevalence of femoral shaft fracture in frontal crashes.
