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51.
This paper gives the results of a series of experiments and how they shed light on problems of electrical fires. Experimental glowing connections were made by allowing wires to make poor contact with another object in series in a circuit. Note: The information in this paper was presented in the course “Electrical fires” at the University of Wisconsin—Extension, Madison, Wisconsin, April 1982.  相似文献   
52.
Engineering decisions concerning the performance of existing structures must be made in the presence of uncertainties. The remaining capacity of corroded steel structures provides a good example of different aspects of uncertainty. These include: an unknown or partially known extent of damage; a variability in loading and an uncertain reserve of structural capacity depending on the mode of failure. The theory of structural reliability has been developed to provide a method of analysis for structural safety. In this paper, methods are proposed to compute the component reliability of corrosion-damaged steel members. The application of a recently developed theory called interval probability theory for system reliability is illustrated using the data obtained from actual samples of corroded beams.  相似文献   
53.
The possibility of determining strength and deformation characteristics of soils under field conditions using rod plates is discussed. The mutual relationship between these characteristics is established from results of deep impression of these rods.  相似文献   
54.
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   
55.
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   
56.
Conclusions 1. For anlaysis of circular (polygona) slabs which can be included in the category of absolutely rigid slabs, a practical approximate method of analysis has been developed and experimentally verified which permits determining the bending moments under centrally and eccentrically applied loads acting over a small circular area, as well as at any other points in the slab beyond the limits of the loaded area.2. Monolithic bonding of hexagonal road slabs up to 3–4 m2 in area designed for the N-30 load results in increased design bending moments and, consequently, in thicker pavements. For these slabs it is expedient to use nonrigid joints, which do not transmit bending or torsional moments; however, these slabs must be placed on stabilized beds and their joints must be filled with waterproofing mastic.Translated from Osnovaniya, Fundamenty i Mekhanika Gruntov, No. 5, pp. 19–22, September–October, 1974.  相似文献   
57.
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   
58.
59.
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   
60.
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   
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