Papers by Keyword: Shock Absorption

Abstract: The lack of a periodontium for a dental implant may lead to high stress concentration at the bone level when the implants are prosthetically loaded. The present paper discusses the current possibilities of implant supported prosthesis making in order to mitigate the impact of occlusal forces. The cement layer may serve as an absorber for the strain, but its role is reduced and poses the risk of excess cement retained in the peri-implant tissue. The use of resin materials for the implant supported prosthetic restorations veneering it has been suggested for many years, but their role it is important in the case of full-arch fixed implant-supported prosthesis with cantilever distal extensions and less in single implant restorations. Nowadays, new materials like fiber-reinforced composites and high-performance polymers as PEEK may be used for the framework of the implant supported prosthetic restorations, but also for the implant or the prosthetic abutment realization.

Abstract: Infilled wall is always regarded as a nonload bearing element, its energy-dissipation capacity and impact for the frame structure under earthquake have not been taken seriously. In this paper the function of infilled wall for frame structure was discussed, energy-dissipation capacity of different measures were analysed and compared from the point of passive control theory. This paper provides the reference for the further research of filler wall.

Abstract: The article describes diverse solutions used in the construction of antique wooden beam-structure floors and analyses the viability of their application in reconstructions. The function of the individual layers of their structure is analysed by: 1.Comparing elasticity (shock absorption in accordance to the PN EN 14808:2005 standard) of floors with continuous support (joists lying on a mineral base and joists placed on a layer of sand) with parquets that have punctual support. 2.Comparing the elasticity of parquets lying on a boarding and those placed directly on joists. 3.Analysing the function of woodwork parquet joints in the floor structure. The capability of floors from antique manor houses in South-Eastern Poland to transfer own and usage loads is being assessed in order to make recommendations as to their preservation, relocation or substitution.

Abstract: As a kind of low-carbon, sustainable and environmental-friendly building material, wood has been widely used in ancient timber-frame buildings in China. Chinese ancient timber-structure buildings can not only provide a comfortable indoor environment, but also has an excellent structural behavior. Based on the study of horizontal and vertical layout of structural system, special constructional measures such as Cejiao and Shengqi, the structural behaviors of Chinese ancient timber-frame buildings were studied. Those conclusions were achieved: structural system layout in both horizontal and vertical comply with the existing anti-seismic conceptual design thoughts. When subjected to earthquake, the seismic actions are reduced by means of base sliding isolation, energy dissipation and shock absorption of mortise-tenon joints and tou-kung sets, which make Chinese ancient timber building a multiple aseismic system. Cejiao and Shengqi are equivalent to passive control in modern buildings, which improve the structural integrity, stability and aseismic capacity greatly. The post-and-lintel roof truss is a good way of saving material.

Abstract: A medium speed mill-foundation coupled finite element model was established using ANSYS. The modal and harmonic responses of medium-speed mill were analyzed. The influence of the number of vibration isolators and the ratio of foundation bedplate to equipment on the vibration of mill was analyzed. The shock absorption measures of medium-speed mills were discussed. To get good vibration isolation effect, the maximum horizontal vibration displacement of medium-speed mill with spring vibration-isolated foundation is suggested as 50 μm, and the ratio of foundation bedplate to equipment as 3.0±0.2.

Abstract: SAP2000 was established in a high-rise steel structure buildings numerical analysis model, through the added a full steel support and common support the buckling and structure under earthquake effect of dynamic response analysis, the key research and support for the structure seismic buckling influence on the performance of the, the analysis results show that add fortify buckling support the energy dissipation structure performance than pure frame structure and common support-frame structure.Introduction.

Abstract: Based on the anti-seismic research achievements of tired arch bridge at home and abroad, taking River City Bridge in Jilin as an example, a finite element model is established for dynamic performance analysis by general finite element software midas civil. Natural vibration characteristics of tied arch bridge are calculated as a basis for further dynamic calculation. Firstly, choose appropriate seismic waves according to the geological data. Then perform the dynamic response analysis of this bridge under different loading cases. Dynamic responses of this bridge under longitudinal and transverse seismic waves are studied respectively, and the influence of vertical seismic wave is also considered. It is shown that the influence on seismic response of vertical seismic waves is very obvious. The vertical seismic waves should be considered while doing seismic design of tied arch bridges.

Abstract: Field testing of safety characteristic was conducted on fifteen hardwood athletic floor systems with different constructions according to the procedures defined in Chinese standard GB/T 20239-2006 and EN 14904:2006. Device called Mastrad Skid Tester S885 was used to measure the coefficient of sliding friction (COF) of the fifteen floors and devices called Artificial Athlete Berlin was used to test shock absorption (SA) and vertical deformation (VD) of those floors. The COF of the fifteen hardwood athletic floors is between 0.4 and 0.5. About 80 percent of average of VA was between 1.0 mm and 2.0 mm. About 50 percent of the mean of VD was between 35% and 50%. About 50 percent of that was between 50% and 60%. It is vital to add the requirement of uniformity of the safety properties of hardwood athletic floor systems in Chinese standard. The deviation of the friction and VD can effectively be used to discriminate the uniformity of a floor.

Abstract: How to deal with a conflict between blasting vibration damage of tunnels construction with complex shallow and the efficiency has been always a difficult technical problem. Relying on the Chang Hong Ling tunnel which under-traverses the Jiangchi Town, using of field monitoring method to comparative study on the blasting vibration under different blasting scheme construction, research shows that: the up-step of non-blasting excavation + lower-bench of controlled blasting technique, successfully controls the surface blasting vibration speed within 1.5 cm/s.Then the tunnel can be constructed safely and rapidly, which provides a reference for the blasting excavation engineering in urban.

Abstract: Today, the zoom air was widely used in top grade sport-shoes. Firstly, the function of zoom air, including shock absorption, energy return, light quantization and ornament results were introduced. Secondly, the problem of using the zoom air nowadays was brought forward, through testing the compression and rebounding of the zoom air in sport-shoes, the shock absorption and the energy return of it were researched. The factors of influencing the compression and rebounding of the zoom air were discussed from speed of the athletics and the aging of the zoom air. The speed had effect on the shock absorption performance and energy return performance. The faster the speed was, the smaller the protection the zoom air could offer and the energy feedback were. Ageing would not make the material of the zoom air produce essential change, but may cause the reduction of the gas in the zoom air. All performances of the zoom air were improved after ageing, which means the zoom air in the market was not optimum at present, all this contributed to the lack of united standard. Finally, the method of testing and the standard of evaluation were put forward, which did some early work for the standard of zoom air in producing and testing.