Author: M. J. T. Lewis | Size: 2.3 MB | Format:PDF | Quality:Original preprint | Year: 2009 | pages: 410 | ISBN: 0521110653/0521792975
The Greeks and Romans achieved extraordinary feats of surveying in building their aqueducts, tunnels and roads and in measuring the circumference of the earth and the heights of mountains. This book, which contains translations of all the ancient texts on surveying instruments, including major sources hitherto untapped, sets out to reconstruct the instruments and to explain how they were used. The subject has never been tackled before in this detail, and a level of technical sophistication emerges which must count as one of the greatest achievements of the ancient world.
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kindly upload the following paper, thanks in advanced.
Wind Load Analysis and the Structure Optimization Design of the Steel Structures with ANSYS Journal ****Applied Mechanics and Materials (Volumes 37 - 38) Volume*****Advances in Engineering Design and Optimization Edited by***Yi-Min Deng, Aibing Yu, Weihua Li and Di Zheng Pages******1643-1646 DOI *******10.4028/www.scientific.net/AMM.37-38.1643 Citation*****Zhao Xin Meng et al., 2010, Applied Mechanics and Materials, 37-38, 1643 Online since**November, 2010 Authors*****Zhao Xin Meng, Jian Xin Zhao, Shu Yang Wang, Nan Zhou Keywords***Bio-Oil, Steel Structures, Wind Load
Abstract
In recent years, the bio-oil, as a new kind of clean energy, has been paid with more attentions and has been in rapid development. Meanwhile, the design and research of the bio-oil equipment also has made a great progress. This paper presented the research of the main unit installed steel structure which was with the 3000t yearly capacity. It analyzed and researched the structure and load characteristics of the bio-oil main unit installed steel structure. According to the related research theory and design standards, by using software ANSYS establish the three-dimensional model of the main unit installed steel structure. The paper also analyzed and calculated the wind load. The model structure has been optimized on the foundation of the analyzing preliminary model foundation. The stability of the equipment has been enhanced.
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The present study is focused on the effects of cellulose ethers (CEs) on the kinetics of early
Portland cement hydration. The retarding effects of cellulose ethers on the development of
single cement phases could be traced to the adsorption behaviour of the polymers. A method
was developed to quantify the amount of cellulose ether adsorbed on the surfaces of cement
phases. The specific surface area of some hydrated phases was analysed by determination of
nitrogen gas adsorption isotherms. The amount of adsorbed cellulose ether was determined by
analysing the residual free water of a cement paste by size exclusion chromatography. It could
be demonstrated that the adsorption behaviour of the polysaccharide depends on the mineral
phase and on the degree of substitution (DS), a key parameter of cellulose ether
characterization.
Beside other methods, the hydration processes were monitored in-situ by the means of ultra
sonic measurements, synchrotron X-ray and neutron powder diffraction and environmental
scanning electron microscopy using a field emission gun. The results of all independent
methods showed a good correlation. The following phase reactions could be observed within
the first 24 hours of Portland cement hydration:
1. tri-calcium aluminate + bassanite + water → ettringite (1st generation)
2. bassanite + water → gypsum
3. anhydrite + water → gypsum
4. tri-calcium aluminate + gypsum + water → ettringite (2nd generation)
5. tri-calcium silicate + water → calcium silicate hydrates + portlandite
It turned out that cellulose ethers had a strong direct effect on the hydration of the silicate
components of cement. Tri-calcium silicate and its hydration products showed the highest
values of polymer adsorption. The adsorption led to a surface intoxication and therefore to
delayed hydration reaction. The effects of cellulose ethers on the aluminates were less
specific. No CE adsorbed on the surface of ettringite, a hydration product of tri-calcium
aluminate and calcium sulphates. Nevertheless the ettringite crystallization after 4 hours was
strongly retarded by cellulose ethers depending on their DS. This retardation was an indirect
phenomenon caused by delayed development of ion-concentration in the pore water. This
delay again was a consequence of the retardation of the silicate hydration caused by cellulose
ethers. In general it can be said that the lower the degree of substitution of the cellulose
ethers, the larger the amount of adsorbed polymers and the stronger the retarding effect.
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(Execution of steel structures and aluminium structures) Part 2: Technical requirements for steel structures
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there is a new annex to BS EN 1090-2: "BS EN 1090-2:2008+A1:2011 Execution of steel structures and aluminium structures. Technical requirements for steel structures"
If someone of you have it or could find it - please share it.
If anyone has access to this journal, I would appreciate a lot if she/he may upload this article:
Shinozuka, M., Deodatis, G. (1991), Simulation of Stochastic Processes by Spectral Representation, Applied Mechanics Reviews, ASME, Vol. 44, 4, p. 191-204.
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Base Isolation and Damage-Resistant Technologies for Improved Seismic Performance of Buildings
Author: Andrew H. Buchanan, et al. | Size: 8.3 MB | Format:PDF | Quality:Original preprint | Publisher: University of Canterbury | Year: 2011 | pages: 99
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It provides comprehensive coverage of both plates and shells and a unique blend of modern analytical and computer-oriented numerical methods in presenting stress analysis in a realistic setting. It is distinguished by its broad range of exceptional visual interpretations of the solutions, applications, and means by which loads are carried in beams, plates and shells. Combining the modern-numerical, mechanics of materials, and theory of elasticity methods of analysis, it provides an in-depth and complete coverage of the subject, not explored by other texts. Its flexible organization allows instructors to more easily pick and choose topics they want to cover, depending on their course needs. Students are exposed to both the theory and the latest applications to various structural elements. Two new chapters on the fundamentals provide a stronger foundation for understanding the material. An increased emphasis on computer tools, and updated problems, examples, and references, expose students to the latest information in the field.
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I need the solution manual for the book "Stresses in Plates and Shells" By A.C. Ugural.
If anybody has please share that.
I would really appreciate it.
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