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881.
Adopting the element SOLID65 and LINK8 in the general finite element analysis software ANSYS and fiber model beam-column element based on finite element flexibility method respectively, the comparative analysis of the cross, L and T-shaped RC columns under compression, bending, shear and torsion with flange width-thickness ratio of 4:1 is carried out. The applicability of plane section assumption in the nonlinear analysis is discussed primarily, which shows that it is feasible on the whole for shaped RC columns with flange width-thickness ratio equal to or smaller than 4:1. 相似文献
882.
The conservation of historic buildings and their environment is an unavoidable problem in urban construction. In this paper, the authors give a few new thoughts about the problem. First, the historic buildings are important part of the core power in city competition.Second,the conservation work should be combined with their development. Third, a classified and multilevel system of protection and reuse of old buildings should be set up. 相似文献
883.
A method of preparing the spinel LiV_(x)Mn_(2-x)O_(4) with liquid phaseis introduced at a low temperature. With cyclic voltammogram and discharge-charge tests at content current, we find that the doped vanadium leads to the spinel structure more stable, the reversible behaviors of LiV_(x)Mn_(2-x)O_(4)is improved, and the capacity fade on cycling is reduced.The cycle life of the battery based on LiV_(x)Mn_(2-x)O_(4)is also found improved. 相似文献
884.
A theoretic model is proposed based on the mechanism of the buckling failure of the stitched composite laminates containing delaminations. The buckling strength of the stitched composite laminates under the in-plane compressive load is predicted. The critical percentage elongation of the stitching thread is taken into account as a control parameter of the buckling failure. The energy method is used to calculate the buckling strength of the stitched composite laminates, and the minimal potential energy is used to calculate that of the unstitched composite laminates. The result shows that the buckling strength of the stitched composite laminates is larger than that of the unstitched composite laminates. The effects of stitching technical parameters such as the stitch thread diameter, stitch step and stitch space on the stitched composite laminates are also analyzed. 相似文献
885.
CHEN Zuo chang 《保鲜与加工》2002,(2):93-97
With social development, the environment has become one of the major topics in human life. Although the construction project may improve economy and environment, it also may exert negative impact on environment. Cost, schedule and quality are three important objectives of construction project and on the objective of environment have not been focused. The author of this paper reiterated the importance of environmental control for the construction project and key areas to be focused on during the whole process of construction project. 相似文献
886.
887.
Ultra High Molecular Weight Polyethylene (UHMW-PE) is a kind of high anti-wear engineering plastic with many excellent physical and mechanical performances. It has been widely applied in the field of mechanism such as bearing and pump. Effect of load, speed, time on friction and wear properties of Ultra High Molecular Weight Polyethylene(UHMW-PE)plastic alloy bearings under different Lubricating Condition are studied by using MPV-200 model friction and wear testing machine. The test results show that water lubrication reduces the friction coefficient of bearings but increases the wear rate as compared with dry friction. At the same time, wear mechanisms are analyzed systemically. It provides a theoretic basic for practical application of plastic alloy bearings 相似文献
888.
This paper summarized the recent research results about the durability of structures, introduced their current application in durability design, appraisal, estimation of rest life and strategy of maintenance and strengthening as well as in other fields. 相似文献
889.
Development Management (DM) in decision phase, Project Management on behalf of the owner (OPM) in implementation phase and Facility Management (FM) in operation phase are three isolated management tools during traditional life cycle management of construction project. As a result, a lot of potential disadvantages are aroused. In recent years, many research organizations try to reform the traditional method using different integration means. This paper tries to explore into integration of DM, OPM and FM to overcome the malpractice of traditional life cycle management of construction project. The research focuses on three aspects: 1.putting forward the concept of Life Cycle Integrated Management (LCIM), based on management integration theory; 2. Raising a new idea to owner's (operator's) management organization design, which emphasizes on the balance of life cycle objectives; 3. Analyzing an information module, level and method of system integration of Life Cycle Integrated Management Information System. 相似文献
890.
This paper provides a conception of brightness and puts stress upon application of brightness to science of illuminating engineering and actual illuminating engineering. 相似文献