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101.
Loadbearing capacity of infill masonry walls considering the deformation‐based membrane effect 下载免费PDF全文
《Mauerwerk》2018,22(3):151-161
According to currently valid codes, it is not possible to determine the loadbearing capacity of unreinforced infill walls considering the deformation‐based membrane effect by incorporating the exact support conditions. One reason for this is the lack of a validated calculation procedure, which in addition to the equilibrium conditions also realistically represents the compatibility conditions of these systems. In the present paper, therefore, a new non‐linear analytical calculation procedure is presented. The main focus of the analysis of walls subject to area loading is the incorporation of the support conditions and thus the consideration of the deformation‐based membrane compressive force. Through generalised formulation and a standardised notation of the determination equations, different material behaviours and various support conditions can be taken into account with few parameters. On the action side, both lighter loading like wind loads and heavier loading like explosion loads can be considered. Through the implementation of the partial factor concept, it is possible to comply with the requirements of European codes and thus ensure the applicability of the analysis model. 相似文献
102.
由于地质情况和施工原因造成的预应力管桩基础出现的Ⅲ类、Ⅳ类桩的实际情况,综合考虑了多方面的因素后采用了注浆技术对Ⅲ类、Ⅳ类桩进行了处理使其桩身完整性达到Ⅰ类、Ⅱ类桩的要求。结合工程实例,就该注浆技术方案的设计及其注浆施工工艺,并对注浆效果进行的检测及评价。对类似工程的Ⅲ类、Ⅳ类桩处理进行了简要的阐述,起一定的借鉴作用。 相似文献
103.
Priyanka Devi Pantula Srinivas Soumitri Miriyala 《Materials and Manufacturing Processes》2017,32(10):1162-1171
KERNEL – A novel parameter-free surrogate building algorithm using Adaptive Neuro Fuzzy Inference System (ANFIS) is presented to provide an intelligent and robust technology to optimally estimate the configuration of ANFIS along with Sobol-based fast sample size determination (SSD) methodology. The proposed algorithm is capable of fine-tuning the existing knowledge base about the physics of the process in terms of human experience. It also enables knowledge discovery through a multi-objective optimization problem (MOOP) solved by non-dominated sorting genetic algorithm, NSGA-II, thus presenting machine-invented physics of the process. Experimentally validated polymerization reaction network model is considered and ANFIS surrogates are built using KERNEL. Surrogate-based optimization was found to be nine times faster than conventional optimization using the time expensive model, thus enabling its online implementation. Comparison of ANFIS with Kriging is also included. 相似文献
104.
Structural parts used in boilers, turbines, ships, and many household purposes are manufactured through sheet metal forming processes. During manufacturing, the micro structure of the material is deformed and micro cracks along with anisotropic properties get induced. Present research deals with a thin sheet metal plate containing a central crack subjected to mixed mode (I+II) loading. With special reference to Lankford's coefficient and degree of anisotropy, the effect of anisotropic triaxiality on crack initiation angle has been investigated. The result reveals the combinations of Lankford's coefficient and degree of anisotropy for which crack initiation angle do not change. 相似文献
105.
Federica Goffi 《Architectural Design》2016,86(1):24-33
Differentiating between the static impulse to preserve and the more open-ended and imaginative process of conservation, Federica Goffi presents a building as ‘a fabric that, even when complete, is unfinished and open to change’. Associate Professor and Associate Director of Graduate Programs at the Azrieli School of Architecture and Urbanism at Carleton University in Ottawa, Goffi has written widely on the topic of time, particularly taking St Peter's in the Vatican by way of example. 相似文献
106.
Y. C. Sharma G. Prasad D. I. Rupainwar 《The International journal of environmental studies》2013,70(4):315-320
The adsorption of Cd(II) onto wollastonite has been reported. Adsorption increased from 55.7 to 93.6% by decreasing the concentration of Cd(II) from 2.0 x 10‐4M to 0.5 x 10‐4M. The rearranged Lagergren equation has been used for dynamic modelling of the process. However, the value of rate constant at 30°C was found to be 3.17 x 10‐2min‐1. Equilibrium modelling was carried out using the Freundlich isotherm equation and constants have been calculated. Thermodynamic studies were carried out and values of standard free energy (?G°), enthalpy (?H°) and entropy (AS°) were calculated at various temperatures. Low temperatures favour the uptake of Cd(II) in the process. 相似文献
107.
Edward T. Urbansky Michael R. Schock 《The International journal of environmental studies》2013,70(5):597-637
Recent reports have attempted to show that fluoridating potable water is linked to increased levels of lead(II) in the blood. We examine these claims in light of the established science and critically evaluate their significance. The completeness of hexafluoro‐silicate hydrolysis is of paramount importance in ensuring that total water quality is maintained. The possible impacts of such complexes as PbII—F—SiF5 or PbFx (2‐x) are discussed as are the contributions of fluoridation byproducts to total acid content. We calculate the fractional distribution of aqueous species based on known chemical equilibria and show the species concentrations for several different model tap waters. We discuss and quantitatively show the effects of other complexing anions, such as carbonate or hydroxide. Overall, we conclude that no credible evidence exists to show that water fluoridation has any quantitatable effects on the solubility, bioavailability, bio‐accumulation, or reactivity of lead(0) or lead(II) compounds. The governing factors are the concentrations of a number of other species, such as (bi)carbonate, hydroxide, or chloride, whose effects far exceed those of fluoride or fluorosilicates under drinking water conditions. Lastly, we consider some previous epidemiological studies of lead(II) exposure and how recent papers fare methodologically. 相似文献
108.
In this work a newly semi polar extraction phase of carboxylated multiwalled carbon nanotube (MWCNTs) reinforced sol-gel immobilized polypropylene hollow fiber was prepared by low temperature hydrothermal process. It is coupled with flame atomic absorption spectroscopy was employed in the extraction and determination of cobalt and cadmium ions in wastewaters. The main factors influencing the pre-concentration and extraction of the metal ions have been examined in detail. Detection limits obtained in this way for Co(II) and Cd(II) ions were 0.0186 and 0.024 ng mL?1, respectively. 相似文献
109.
Suman Sarkar 《Sequential Analysis》2016,35(2):207-215
We consider two treatment comparison in a clinical trial setup where the responses from one treatment are a priori known for a fixed number of individuals and patients are allocated in a groupsequential way for the other treatment using inverse sampling. We consider the odds ratio as the measure of treatment difference at the end of each group, where for the calculation of odds ratios we consider the full data on one treatment, which are a priori known, and the available data on the other treatment up to that point of time. We have calculated the optimal number of index subjects for inverse sampling and examine the effects of different type I and type II error spending functions on group sequential testing in this context. The methodology is illustrated by using a real data set. 相似文献
110.
设计并合成了一种新型的含有大体积基团phenyl的α-二亚胺配体1a及其Ni(Ⅱ)配合物1b,采用NMR谱、XPS对其进行了表征。研究了聚合条件如Al/Ni摩尔比、聚合反应温度及配体结构等因素对催化剂活性的影响。在反应温度为5℃,Al/Ni摩尔比为800时,该催化体系催化乙烯聚合的活性最高,可达5.57×106g PE/(molNi·h·bar),所得聚乙烯具有较高的支化度,最高可达136 branches/1000C。采用1H NMR、DSC、GPC、TG分别对聚合物进行了表征。 相似文献