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41.
V. D. Kazarnovskii E. S. Pshenichnikova 《Soil Mechanics and Foundation Engineering》1993,30(4):145-148
It was shown that in order to compute the settlement of thawing cohesive soil under a load in time it is necessary to experimentally determine the consolidation coefficient. A procedure is suggested for determining this coefficient, as well as use of the classical solution of a differential equation for seepage consolidation to describe the settlement of soil, thawing of which can occur according to any law.State All-Union Scientific Research Institute of Roads. Translated from Osnovaniya, Fundamenty i Mekhanika Gruntov, No. 4, pp. 5–7, July–August, 1993. 相似文献
42.
Somlai J Gorjánácz Z Várhegyi A Kovács T 《The Science of the total environment》2006,367(2-3):653-665
High radon concentration (average 410 kBq m-3) has been measured in a tunnel of a uranium mine, located 15-55 m below the village of Kovágószolos, Hungary. The mine was closed in 1997; the artificial ventilation of the tunnel was then terminated and recultivation works begun. In this paper, a study has been made as to whether the tunnel has an influence on the radon concentration of surface dwellings over the mining tunnel. At different distances from the surface projection of the mining tunnel, radon concentration, the gamma dose, radon exhalation and radon concentration of soil gas were measured. The average radon concentration in the dwellings was 483 Bq m-3. Significantly higher radon concentrations (average 667 Bq m-3) were measured in houses within +/-150 m from the surface projection of the mining tunnel +50 m, compared with the houses further than the 300-m belt (average 291 Bq m-3). The average radon concentration of the soil gas was 88.8 kBq m-3, the average radon exhalation was 71.4 Bq m-2 s-1 and higher values were measured over the passage as well. Frequent fissures crossing the passage and running up to the surface and the high radon concentration generated in the passage (average 410 kBq m-3) may influence the radon concentration of the houses over the mining tunnel. 相似文献
43.
This paper presents the development of a comfort index that measures adaptivity in outdoor spaces. Over a 9-month period 649 people were surveyed in three locations, in temperatures between 10 and 28 °C. An exploratory factor analysis develops a 15-item scale of comfort that includes measures of adaptivity: clothing, exposure time and seating location. The scale is regressed on physical measures: average instantaneous wind speed; maximum wind speed; mean-exposed radiant temperature; mean-shaded radiant temperature and ambient temperature. The results model the relative contributions of the microclimatic factors for the comfort in the outdoor space. Analyses suggest gustiness and wind speed are most important in determining user satisfaction. There is strong support for the theory that people actively adapt to microclimatic conditions. 相似文献
44.
Conclusions 1. The scheme that we developed is efficient and ensures thawing over a period of 40–45 days.
2. To accelerate thawing by 8–10 days when using two electric heaters in each hole, it is necessary to raise the heaters by
3–4 m after 25 days and continue thawing.
3. An 8–10-day reduction in the thaw time is also possible by using three 1.25-kW electric heaters in each hole in place of
two heaters of the same capacity, installing them at depths of 20, 14, and 8 m from the surface.
Taking the results of the experimental work account, the State Institute for Special Design developed a plan for the production
preconstruction thawing of soils over a area of 12,380 m2.
The volume of soil thawed was 324,400 m3.
Translated from Osnovaniya, Fundamenty i Mekhanika Gruntov, No. 3, pp. 7–8. May–June, 1982. 相似文献
45.
V. I. Sheinin V. V. Mikheev N. B. Popov Yu. V. Lesovoi 《Soil Mechanics and Foundation Engineering》1991,28(2):79-83
Conclusions 1. The method proposed for the probabilistic design of beds makes it possible to obtain a well-founded design solution corresponding
to a given reliability level, which, in many cases, is more economic than the solution recommended in the Construction Rules
and Regulations.
2. The design solution adopted as a result of the calculation set forth in the Construction Rules and Regulations possesses
a reliability level, which, for some unknown reason, is on the high side.
Translated from Osnovaniya, Fundamenty i Mekhanika Gruntov, No. 2, pp. 18–20, March–April 1991. 相似文献
46.
The history of the development of methodical and regulatory documents relative to construction in karst-prone areas is cited.
The basic content of existing regulatory documents is presented, and attention is focused on some of their deficiencies. Specific
approaches to the development of a standard for construction in karst-prone areas are proposed.
__________
Translated from Osnovaniya, Fundamenty i Mekhanika Gruntov, No. 6, pp. 21–24, November–December, 2006. 相似文献
47.
N. A. Klimenko L. V. Nevinnaya Yu. V. Sidorenko O. G. Shvidenko Yu. O. Shvadshina 《Journal of Water Chemistry and Technology》2007,29(1):15-22
We have studied the process of a prolonged dynamic filtration on activated carbon in two biosorption systems — without preoxidation treatment of the initial matter and after ozonization. It has been shown that given the uniform load on activated carbon terms of the organic matter the efficiency of the biosorption process after preozonization is 2.3 times as small compared with that that without pretreatment, which correlates with the change of adsorption free energy. 相似文献
48.
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