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51.
Empirical nonlinear analysis of combined piled‐raft foundation (CPRF). Depending on load‐settlement curve obtained from field measurements or empirical relations, a nonlinear analysis of combined piled‐raft is presented to take into account the actual response of subsoil behavior. In the analysis, each pile is treated as two units, shaft and base, having a uniform settlement along the pile shaft and in the pile base. This assumption enables modeling the nonlinear behavior of combined piled‐raft. The nonlinear response of the pile is based on the DIN 4014 empirical relation of load‐settlement curve. Connecting between empirical and theoretical procedures, a method termed NPRD for nonlinear analysis of combined piled‐raft using DIN 4014 is developed. The procedure meets the requrements of the KPP‐guideline, section 6, to a computation model. The efficiency of NPRD is demonstrated in a comparison computation of Frankfurt Messeturm with the results of different authors. The proposed method was implemented in the program ELPLA. The special cases “single pile/pile group” and “raft” are contained in. 相似文献
52.
This paper presents a mathematical model that was developed specifically to calculate the produced shaded and sunlit areas in a circular courtyard geometry. It examines the interaction taking place between the sun at any time throughout the year and a circular courtyard form with any dimensions and proportions in any place on the earth. This model was included in a new computer program, which allowed detailed investigation to be undertaken into the effect of circular courtyard proportions on the generated wall and floor exposed and shaded areas. The results showed that changing the form's proportions significantly influences the shading or exposure potential of the internal courtyard envelope. 相似文献
53.
A GIS-based DRASTIC model for assessing aquifer vulnerability in Kakamigahara Heights, Gifu Prefecture, central Japan 总被引:14,自引:0,他引:14
Vulnerability assessment to delineate areas that are more susceptible to contamination from anthropogenic sources has become an important element for sensible resource management and land use planning. This contribution aims at estimating aquifer vulnerability by applying the DRASTIC model as well as utilizing sensitivity analyses to evaluate the relative importance of the model parameters for aquifer vulnerability in Kakamigahara Heights, Gifu Prefecture central Japan. An additional objective is to demonstrate the combined use of the DRASTIC and geographical information system (GIS) as an effective method for groundwater pollution risk assessment. The DRASTIC model uses seven environmental parameters (Depth to water, net Recharge, Aquifer media, Soil media, Topography, Impact of vadose zone, and hydraulic Conductivity) to characterize the hydrogeological setting and evaluate aquifer vulnerability. The western part of the Kakamigahara aquifer was dominated by "High" vulnerability classes while the eastern part was characterized by "Moderate" vulnerability classes. The elevated north-eastern part of the study area displayed "Low" aquifer vulnerability. The integrated vulnerability map shows the high risk imposed on the eastern part of the Kakamigahara aquifer due to the high pollution potential of intensive vegetable cultivation. The more vulnerable western part of the aquifer is, however, under a lower contamination risk. In Kakamigahara Heights, land use seems to be a better predictor of groundwater contamination by nitrate. Net recharge parameter inflicted the largest impact on the intrinsic vulnerability of the aquifer followed by soil media, topography, vadose zone media, and hydraulic conductivity. Sensitivity analyses indicated that the removal of net recharge, soil media and topography causes large variation in vulnerability index. Moreover, net recharge and hydraulic conductivity were found to be more effective in assessing aquifer vulnerability than assumed by the DRASTIC model. The GIS technique has provided efficient environment for analyses and high capabilities of handling large spatial data. 相似文献
54.
The UK government’s framework for regeneration, “Transforming Places, Changing Lives”, seeks to shape the way regeneration is conducted in England. The emphasis on economic transformation should not be unexpected, considering the Index of Multiple Deprivation – a key measure used throughout the UK literature for several years – has an emphasis on economic dimensions of deprivation. The paper critically assesses the manner in which the ‘localism’ of regeneration policy implementation is being promoted in the literature, while simultaneously using a national metric as an evidence base for action. 相似文献
55.
Clare Mulholland Mohamed Gamal Abdelmonem Gehan Selim 《土木工程与建筑:英文版》2014,(6):746-760
The paper examines the role of shared spaces in divided cities in promoting future sustainable communities and spaces described as inclusive to all. It addresses the current challenges that prevent such inclusiveness and suggests future trends of its development to be of benefit to the wider city community. It explains how spaces in divided cities are carved up into perceived ownerships and territorialized areas, which increases tension on the shared space between territories; the control of which can often lead to inter-community disputes. The paper reports that common shared space in-between conflicting communities takes on increased importance since the nature of the conflict places emphasis on communities' confidence, politically and socially, while also highlighting the necessity for confidence in inclusion and feeling secure in the public domain. In order to achieve sustainable environments, strategies to promote shared spaces require further focus on the significance of everyday dynamics as essential aspects for future integration and conflict resolution. 相似文献
56.
ABSTRACTThis paper examines the performance of environmental strategies in seven recently constructed or refurbished university buildings in the UK. These buildings contain a range of administrative spaces, classrooms, libraries and studios, reflecting their often complex, multi-use, heterogeneous nature. The key features of each environmental strategy are described (including passive, mixed-mode or active systems), in the context of the occupants and spaces they serve and the level of interaction that they afford. Energy performance and occupant thermal comfort (assessed by user surveys) are analysed and compared with studies of other non-domestic buildings, which have typically focused on more predictable single administrative uses (e.g. government offices), and unusually effective operation scenarios (e.g. continuous monitoring by expert building managers). The paper concludes by examining two of the case studies that reflect an increasingly common model of ‘flexible’ environmental design in more detail, identifying key features of the strategies for each building that have had a significant impact on their performance. The design assumptions leading to these features will be explored, and key lessons identified, contributing towards the development of a more robust evidential basis for choosing appropriate environmental strategies for university and other non-domestic buildings in the UK. 相似文献
57.
Experiments were performed wherein conical frusta of aluminium of thicknesses between 0.7 and 1.62 mm and semi-apical angles range of 16–29° were axially compressed in a universal testing machine. The load–deformation curves and deformed shapes of specimens were recorded. These deformed in axisymmetric concertina mode and non-symmetric diamond modes.A three dimensional numerical simulation was carried out for all samples tested under quasi-static loading using ANSYS®. Various stages of collapse of the shell, including non-symmetrical lobe formation were simulated for the first time, and material, geometric and contact non-linearities were incorporated. The plastic region of the material curve was assumed to be piecewise linear. Tensile tests were performed on standard samples to obtain stress–strain curves. Results thus obtained compared well with the experiments.Based on the formation of rolling and stationary plastic hinges an analysis was also carried out to study the behaviour of shells under axial compression and results were compared with experimental and numerical results. 相似文献
58.
Hamid Bourenane Youcef Bouhadad Mohamed Tas 《Bulletin of Engineering Geology and the Environment》2018,77(4):1473-1489
The city of Boumerdès, located in Northern Algeria, was badly affected during the May 21, 2003 Zemmouri (Mw = 6.8) earthquake where extensive liquefaction has been reported. The aim of this paper is to assess and to map the liquefaction potential for Boumerdès. We collected and used data from 154 boreholes, 10 down-hole tests, 56 standard penetrations tests (SPT), and inventory of 35 water level points. This data has been analyzed in the framework of geographical information systems (GIS). We assessed the liquefaction potential index (LPI) by considering a seismic hazard scenario corresponding to amax = 0.48 g calculated, using a probabilistic approach, for a return period of 500 years. LPI values have been correlated to compile the liquefaction hazard map that indicates the quantitative characteristics of the liquefiable layers and the induced disruption probability area. Results show that the main part of the city of Boumerdès belongs to a low liquefaction potential area except for a narrow corridor along the Corso waterway, where the liquefaction potential is moderate to high. The obtained results are compatible with the geological, geotechnical and hydrogeological susceptibility to liquefaction of the area. The results also show a good agreement with the observations made after the May 21, 2003 Zemmouri earthquake. The obtained liquefaction hazard maps may serve as useful tools for land management and planning in the city of Boumerdès and as an example of liquefaction hazard assessment that may be applied in other populated cities in northern Algeria’s seismic prone areas. 相似文献
59.
For an induction machine, we suggest a theoretical development of the mechanical unbalance effect on the analytical expressions of radial vibration and stator current. Related spectra are described and characteristic defect frequencies are determined. Moreover, the stray flux expressions are developed for both axial and radial sensor coil positions and a substitute diagnosis technique is proposed. In addition, the load torque effect on the detection efficiency of these diagnosis media is discussed and a comparative investigation is performed. The decisive factor of comparison is the fault sensitivity. Experimental results show that spectral analysis of the axial stray flux can be an alternative solution to cover effectiveness limitation of the traditional stator current technique and to substitute the classical vibration practice. 相似文献
60.
Tool wear is an important machinability criterion. To reduce total machining costs, this study demonstrates the wear and tribological performance of four ceramic tools in dry high-speed turning of Ni-Co-Cr precipitation hardenable superalloy (Inconel 100). Wear of the tool materials and the structural and phase transformations at the tool–chip interface were investigated. Results obtained reveal that SiAlON ceramic outperformed other ceramic tool materials at different cutting speeds due to the formation of a large amount of mullite tribofilms on the tool face, which serve as a thermal barrier layer. Alumina ceramic with the addition of ZrO2 can be recommended for machining Inconel 100 at speeds above 150 m/min due to its ability to form thermal barrier ZrO2 tribofilms, which decrease the coefficient of friction at the tool–chip interface. Mixed alumina and an alumina matrix reinforced with SiCw were found to be unsuitable for machining age-hardened Inconel 100 superalloy. 相似文献