The function of Gastrointestinal tract including intestine is to a large degree mechanical.The mechanical properties of the intestinal wall,and the tonic (sustained) and/or phasic(short-
Based on elastic theory of different tension-compression modulus, the analytical solution was deduced for bending-compression column subject to combined loadings by the flowing coordinate system and phased integration...Based on elastic theory of different tension-compression modulus, the analytical solution was deduced for bending-compression column subject to combined loadings by the flowing coordinate system and phased integration method. The formulations for the neutral axis, stress, strain and displacement were developed, the finite element program was compiled for calculation, and the comparison between the result of finite element and analytical solution were given too. Finally, compare and analyze the result of different modulus and the same modulus, obtain the difference of two theories in result, and propose the reasonable suggestion for the calculation of this structure.展开更多
A surface nanocrystalline was fabricated by ultrasonic shot peening(USSP)treatment at AZ31 Mg alloy.The effect of nanocrystalline thickness and its placed side(external or internal)on the bendability was studied by a ...A surface nanocrystalline was fabricated by ultrasonic shot peening(USSP)treatment at AZ31 Mg alloy.The effect of nanocrystalline thickness and its placed side(external or internal)on the bendability was studied by a V-bending test.Three durations,5,10,and 15 min,were applied to form the surface nanocrystalline with thicknesses of 51,79,and 145μm,respectively.Two-side treatment led to a similar bendability as that of as-received.One-side internal treatment for 5 min resulted in an improved bendability while the improvement was limited and degenerated for longer treatment.The improvement was related to the drawing back of the neutral axis.The one-side external treatment also improved the bendability,and the improvement was due to the redistribution of strain and stress during bending.With nanocrystalline at external side,it resulted in a larger stress but a smaller strain at the convex,which prevented the happening of crack during bending.展开更多
A bending beam,subjected to state of plane stress,was chosen to investigate.The determination of the neutral surface of the structure was made,and the calculating formulas of neutral axis,normal stress,shear stress a...A bending beam,subjected to state of plane stress,was chosen to investigate.The determination of the neutral surface of the structure was made,and the calculating formulas of neutral axis,normal stress,shear stress and displacement were derived.It is concluded that, for the elastic bending beam with different tension-compression modulus in the condition of complex stress, the position of the neutral axis is not related with the shear stress, and the analytical solution can be derived by normal stress used as a criterion, improving the multiple cyclic method which determines the position of neutral point by the principal stress. Meanwhile, a comparison is made between the results of the analytical solution and those calculated from the classic mechanics theory, assuming the tension modulus is equal to the compression modulus, and those from the finite element method (FEM) numerical solution. The comparison shows that the analytical solution considers well the effects caused by the condition of different tension and compression modulus. Finally, a calculation correction of the structure with different modulus is proposed to optimize the structure.展开更多
文摘The function of Gastrointestinal tract including intestine is to a large degree mechanical.The mechanical properties of the intestinal wall,and the tonic (sustained) and/or phasic(short-
文摘Based on elastic theory of different tension-compression modulus, the analytical solution was deduced for bending-compression column subject to combined loadings by the flowing coordinate system and phased integration method. The formulations for the neutral axis, stress, strain and displacement were developed, the finite element program was compiled for calculation, and the comparison between the result of finite element and analytical solution were given too. Finally, compare and analyze the result of different modulus and the same modulus, obtain the difference of two theories in result, and propose the reasonable suggestion for the calculation of this structure.
基金financially supported by the Natural Science Basic Research Program of Shaanxi,China(No.2021JQ-250)the Fundamental Research Funds for the Central Universities(No.300102220301)。
文摘A surface nanocrystalline was fabricated by ultrasonic shot peening(USSP)treatment at AZ31 Mg alloy.The effect of nanocrystalline thickness and its placed side(external or internal)on the bendability was studied by a V-bending test.Three durations,5,10,and 15 min,were applied to form the surface nanocrystalline with thicknesses of 51,79,and 145μm,respectively.Two-side treatment led to a similar bendability as that of as-received.One-side internal treatment for 5 min resulted in an improved bendability while the improvement was limited and degenerated for longer treatment.The improvement was related to the drawing back of the neutral axis.The one-side external treatment also improved the bendability,and the improvement was due to the redistribution of strain and stress during bending.With nanocrystalline at external side,it resulted in a larger stress but a smaller strain at the convex,which prevented the happening of crack during bending.
文摘A bending beam,subjected to state of plane stress,was chosen to investigate.The determination of the neutral surface of the structure was made,and the calculating formulas of neutral axis,normal stress,shear stress and displacement were derived.It is concluded that, for the elastic bending beam with different tension-compression modulus in the condition of complex stress, the position of the neutral axis is not related with the shear stress, and the analytical solution can be derived by normal stress used as a criterion, improving the multiple cyclic method which determines the position of neutral point by the principal stress. Meanwhile, a comparison is made between the results of the analytical solution and those calculated from the classic mechanics theory, assuming the tension modulus is equal to the compression modulus, and those from the finite element method (FEM) numerical solution. The comparison shows that the analytical solution considers well the effects caused by the condition of different tension and compression modulus. Finally, a calculation correction of the structure with different modulus is proposed to optimize the structure.
