Applied Mechanics and Materials Vols. 94-96

Abstract: JINPIN Hydropower Station is a high arc dam of world class, and it is a difficult problem to set up scaffold in the treatment of high sloping of atomization region on two banks. Adopt fastener steel-pile scaffold combining with anchor wires, and set up the super-high working platform. This paper introduced the method of setting up the fastener steel pile scaffold, and special construction measures in the treatment of high sloping, which can be referential for scaffolding works.

Abstract: Because of large flexibility and strong geometric nonlinearrity, the time domain method should be applied in the analysis of wind-induced vibration for the membrane structure, and the coupling effect between the structure and the fluid should also be considered. In this problem, it is hard now to solve it directly using the technique of three-dimensional transient FSI based on CFD. So in the article, a compromise schedule is proposed, i.e, for the mean wind part, the steady-state FSI technique is applied to solve the parameter such as the mean pressure coefficient, the mean wind velocity, etc, while for the fluctuating wind part, the time integral method is used based on the stochastic function of the wind velocity formed by auto regressive method. The aerodynamic damping is considered in the solving of fluctuating part and five computing schedule are compared, result shows that it is better to use positive mean wind damping for the nodes. It is also suggested that the stochastic wind velocity functuion can be revised based on the kinetic energy distribution of the reference points. A comparison between the computing and testing results show that it is greatly improved for the fluctuating response distribution of the structure.

Abstract: Abstract：Rushing trough is often used as drainage in steep slope section, velocity of flow can be reduced and water-damage of road can also be prevented furtherly if multi-step energy dissipation facility is placed in rushing trough. In this paper, CFD method is adopted and VOF calculating model is established and turbulent kinetic energy and turbulent dissipation rate are introduced as standard to analyse energy dissipation mechanics of the facility. The factors such as height of embankment, gradient of trough, size of step and velocity of flow in inlet, which can influence efficiency of energy dissipation, are also discussed in the paper and regression formula about efficency of energy dissipation is presented. All the conclusion can guide the design of consumed energy facility.

Abstract: Based on urban heating situation in north, economic evaluation for different heating modes was analyzed in the presented work. Firstly through collecting and analyzing the urban heating system data, initial investment and operation cost were deduced for several main heating modes. And only fuel cost was taken into account in operation fuel cost for simplicity. Secondly economic evaluation for whole energy heating modes was done and compared. Finally the best heating mode was found which can be a reference for decision on urban heating mode in north.

Abstract: With the Drucker-Prager yield criterion, the ANSYS software is used to analyze the long-short-pile composite foundation by using three-dimensional nonlinear finite element method. The influences of load on axial stress and maximal axial stress of head of pile with cushion or not have been investigated by simulating composite foundation through nine long piles and sixteen short piles. The result indicates the cushion can reduce the stress concentration in head of pile effectively with increase of load. This conclusion has a certain value for engineering.

Abstract: A methodology of damage identification for the circumferentially cracked pipe is presented by using the quantitative relationship between crack size and reflection characteristics of guided waves. Firstly, the reflection characteristics and mode conversion behavior were theoretically studied by the 3-D finite element (FE) analysis. It is found that the reflection coefficients (RCs) of longitudinal L(0,2) and F(1,3) modes quantitatively is related to the circumferential length and radial depth of the crack. Then we present a novel method to quantitatively identify the crack. The feasibility of the proposed method was numerically investigated. The method only requires the longitudinal excitation mode of guided wave in the pipe, which shows the good potential for real application or in-situ damage monitoring. Introduction

Abstract: A method of removal of chloride in reinforced concrete was proposed by anodic oxidation of silver in the pore solution with chloride content over 0.4% by weight. The result shows that after anodic oxidation of silver plate the polarisation resistance of rebar will increase to the range of safety. The silver plate can be applied repeatedly.

Abstract: Abstract. this paper proposes an energy saving algorithm based on wireless network in the intelligent street lamp system, which can real-time intelligent detect conditions illumination, person’s position and other infomation, street lamps builds a WSN network and collaborative adjustment its illuminations according to the information collected by its sensor device,compared with the current lighting system, the system more benefit in energy saveing, extending the lamp life, reduce light pollution on the environment. For energy conservation and environmental protection construction, intelligent street lamp system play an important role.

Abstract: Aiming at the complexity and uncertainty of rock and soil body, the paper proposed a tunnel surrounding rock parameters identification method combining numerical simulation, particle swarm optimization and artificial neural network. The method acquired data set between rock soil parameters and monitoring displacement and trained artificial neural network. The analytical theory and method are introduced in detail, analyzes the tunnel of Dalian Metro by the proposed method, and gets satisfied results. Which states that the parameters identification method based on PSO-ANN is feasible and has good foreground.

Abstract: Based on the constitutive models of steel and core concrete,the failure modes and the load-displacement curves of the solid multibarrel tube-confined concrete columns(CHS inner and SHS outer) under monotonic loading are calculated by using finite element analysis (FEA) method.The analytical results reveal the rules of stress distribution in steel and core concrete.The influences of axial compression ratio, yield strength of steel tube and concrete on the load-displacement curves are discussed.Through the results,it is deeply known the working mechanism of members(CHS inner and SHS outer) subjected to the static loads.