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11.
12.
Results are presented for laboratory and field tests of weak saturated soils serving as beds for embankments in Ho Chi Min
City and various regions of the Mekong River Delta (Vietnam). A method is outlined for quantitative evaluation of the stress-strain
state (SSS) of the weak saturated clayey beds (plane problem). A method is described for quantitative evaluation of the deformation
and stability of weak beds in the initial, intermediate, and stabilized stages of the formation and transformation of the
SSS.
__________
Translated from Osnovaniya, Fundamenty i Mekhanika Gruntov, No. 5, pp. 2–6, September–October, 2005. 相似文献
13.
14.
The problem of buckling of the Euler–Bernoulli and Timoshenko beams is analyzed by the finite element method. Significant improvement in accuracy of the method is obtained by replacing the discontinuous function of the bending moment related to the approximation of the eigenfunction obtained by FEM by a “smoothed” function in the Rayleigh quotient. The smoothed function is obtained by fitting the discontinuous one using the least square technique. 相似文献
15.
T. Z. Harmathy 《Fire Technology》1972,8(4):326-351
This is the second part of a two-part paper in which the author has endeavored to present all available information on compartment
fires in a consistent theoretical framework. This well-documented review of the state of the art should serve as a valuable
reference for researchers for some time to come.
Note: This paper is a contribution from the Division of Building Research, National Research Council of Canada and is published
with the approval of the Director of the Division. 相似文献
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17.
18.
Pascal De Decker Isabelle Pannecoucke 《Journal of Housing and the Built Environment》2004,19(3):293-309
As long as the social rented sector housed traditional families and the allocation procedures were rather loose, there was little commotion about the sector. A combination of a change in family structures, economic changes, and the strengthening of allocation procedures in favour of those most in need did change perceptions. Marginalisation and ghettoisation, especially of high-rise social housing estates, became buzzwords. This paper deals with the causes of these changes and with their implications. The marginalisation discourse calls for enlarging the target groups and estate-specific allocation procedures (to obtain a `social mix'). It illustrates a profound desire to diminish the number of ethnic minorities, single parents, single-person households and all kinds of people with a weak income profile who gain access to social rental housing. Furthermore, this discourse is reaching a crescendo: after it was started in the early 1990s by staff members of local social housing companies, it passed through the union of the social housing companies, the umbrella organisation of the sector, and parliament, reaching its greatest momentum so far in early 2002 when it was adopted by the Flemish housing minister. The counterpoint to this negative discourse is the high degree of satisfaction among social tenants, as observed in a study carried out in 1999. In our paper we will try to explain the background of these opposing trends and the possible consequences for the social rental housing in general and for tenants in particular. 相似文献
19.
Alisson Rodrigo Souza Reis Sineire Maria Silva Araújo Paulo Ricardo Rodrigues Piovesan 《Holz als Roh- und Werkstoff》2018,76(6):1761-1763
The objective of this study was to anatomically characterize the fibers of nine species of Fabaceae lianas, to determine their potential in papermaking and to define which biometric parameters can be used to distinguish and identify individuals. The species presented average values of 76.81, 57.45, 42.55, and 1.81 for the felting index, wall fraction, coefficient of flexibility, and Runkel index, respectively. It is concluded that only M. ferox and M. madeirense can be recommended for papermaking. 相似文献
20.
The impact of natural and artificial weathering on the visual,colour and structural changes of seven tropical woods 总被引:1,自引:0,他引:1
Ladislav Reinprecht Miroslava Mamoňová Miloš Pánek František Kačík 《Holz als Roh- und Werkstoff》2018,76(1):175-190
This study investigates the effects of wood weathering on changes in its macroscopic and colour characteristics in connection with changes in its molecular and anatomical structure. Seven hardwoods suitable for outdoor architecture—bangkirai, cumaru, cumaru rosa, ipé, jatobá, kusia, and massaranduba—were exposed to the exterior out of ground contact for 1–36 months according to EN 927-3, and for 1–12 weeks in Xenotest with water spraying according to partly modified EN 927-6. With prolonged weathering, the following changes occurred in the top surfaces of all tropical woods: (1) visual—creation of longitudinal macro-cracks, (2) spectrophotometry and CIE-L ? a ? b ? —darkening in exterior exposure mainly due to pollutants, except for ipé, and vice versa lightening in Xenotest, as well as greening and blueing in both modes of exposure, (3) FTIR—faster decrease of guaiacyl than syringyl lignin, absolute decrease of conjugated and unconjugated carbonyl groups in the newly formed lignin-polysaccharide-extractive substrate in the photo-oxidized and washed-out cell walls, and decrease of cellulose crystallinity, (4) SEM—damaging of cell-walls by micro-cracks, and their degradation by thinning. Connections between changes of the individual characteristics of weathered woods, for example, between the colour (ΔE*, etc.) and the molecular structure (carbonyls, etc.), were also determined. 相似文献