Applied Mechanics and Materials Vols. 166-169

Abstract: A new multi-orifice effervescent atomizer used for fire fighting was developed. The droplet size distribution of the spray produced by the nozzle was measured by laser Doppler particle analyzer. And the influence of liquid injection pressure, water flow rate and atomizer internal geometry was studied.

Abstract: The sliding cable structures have found its application in many practical structures, such as ski lifts, electrical transmission lines, and cable systems in the erection procedures of long-span bridges. This paper presents a method for modeling the cable sliding on a pulley or sheaves. “Sliding cable element” is developed to solve the general problem. Based on the foundational principles of finite element analysis, the relation of the forces in the element on equilibrium state is used. The computation is simplified by automatically adjusting the cable length on each side of a pulley or sheave in order to maintain equilibrium. The element models are implemented in a geometrically nonlinear, transient implicit finite element program. Several numerical examples are developed to validate the effective of the sliding cable element.

Abstract: The size, the position and the arrangement of external restraint will significantly affect the mechanical properties of the structures with the external restraint. Based on classical beam theory, the stress distribution of a simply supported beam with externally reinforcing steel bars under transverse loads is analyzed in this presentation. By assuming that the stresses in both the beam and the external constrains are less than their proportional limits, an analytical formulation of normal stress in the cross section of the beam was derived by considering two cases that the externally reinforcing steel bars are pre-stressed and are not pre-stressed. Influences of the parameters of the stiffness and the position of the externally reinforcing steel bars on the stress of the beam are discussed.

Abstract: Applying linear marine hydrodynamics theory, the Kelvin wave source Green function of steady motion in finite depth was decomposed to three parts: array of simple Rankine sources, local distribution and wave part. Both at subcritical and supercritical speed, the singularity of integral function were eliminated by different integral path. The Kelvin source was distributed on the surface of ship by panel method, and the ship pressure distribution and wave pattern of ship in finite depth were calculated. The difference and connection between finite and infinite depth results were compared. It can provide the theoretical arithmetic base of improving the ship seaworthiness, increasing the speed and optimization of ship in river and offshore strip.

Abstract: Two kinds of new exact solutions were offered after studying the variable coefficient KP equation, of which, the group invariant solutions of KP equation was obtained by using Lie group method, while the solitonic solution of KP equation was obtained by using hyperbola function method.

Abstract: In this Paper, Combining the Nonmonotone and Monotone Line Search ,a Spectral Conjugate Gradient Methods Are Used in this Paper. by the Concept of Spectral, we Construct a Class of Spectral Conjugate Gradient with Different form . we Also Give the Algorithm for Conjugate Gradient Method. the Numerical Result Show the Efficiency of the Method.

Abstract: The micro-cracks would occurr with the deformation in the composite materials. It would be expanded to the macro-crack in bonding surface and eventually leads to the overall damage of the structure. The initial defects will be inevitably involved in the production of the laminated composite structures. They also lead to delamination crack propagation and structural damage. This paper focuses on the application of the J-integral in the delamination of the composite laminated structure. The J-integral formula of the planar delamination problem of composite laminated structure was derived and verified in the numerical examples.

Abstract: Models for internal force analysis and strain distribution of joints of steel secondary beam inserted in reinforced concrete frame girder were analyzed. The horizontal internal force and vertical force were considered separately during calculation and analysis process. Bending-shearing correlation of vertical internal force was studied while the horizontal force wasn’t taken into account. Results show that the non-dimensional moment varies linearly with the non-dimensional shear force. Base on this, the formulas by which the joint moment and shear force are calculated are derived, and are related to depth ratio of forward to backward compression zone .And then the method to calculate joint moment capacity under horizontal force is put forward. By investigating the moment and shear force variation, the relationship between the yielding stress of the bar in the slab and the boundary concrete under the steel secondary beam crushing is identified. In the end, practical design method is proposed, and problems need further research are mentioned.

Abstract: Analysis of stress state of soil around the pile and grouting pressure of small non-sand concrete pile is given based on the expansion elastic theory of cylindrical cavity and the unified strength theory, the grouting pressure formula is obtained in the elastic limit state and elastic-plastic state of soil around the pile considered the intermediate principal stress, and the relationship is obtained between the grouting pressure and the plastic radius; When the soil around the pile is in different stress state, the correlativity of crack and densification of grouting is analyzed, and the relationship between the grouting pressure and the plastic radius is discussed with the right coefficient of the intermediate principal stress and initial press under different values. The obtained results have provided efficient analysis means for grouting optimal design of post-processing technology with small non-sand concrete pile.

Abstract: By means of inertia-moment method, formulae are derived for calculating flexural rigidity of RC beams under different loading stage, which can be used for calculating initial rigidity and rigidity in service stage. Involving less parameters, it’s convenient to use the formulae. As for four examples, calculations are carried out by both code method and formulations given in this paper, and satisfied results are shown. Further more, based on finite rib method, nonlinear-all-rang analysis is done for M-B of beam sections.