Wyniki wyszukiwania - BazTech

1

Wind tunnel model tests of snow precipitation and redistribution on rooftops, terraces and in the vicinity of high-rise buildings

Flaga A., Bosak G., Pistol A., Flaga L.

Archives of Civil and Mechanical Engineering

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2019

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Vol. 19, no. 4

1295--1303

EN

This paper describes the model tests conducted in the Wind Engineering Laboratory of the Cracow University of Technology aimed at determining the shape coefficients of snow load on high-rise buildings of The Warsaw Hub. The shape coefficient was measured at two different situations: snow precipitation and its subsequent redistribution. The model tests were conducted independently for rooftops and terraces in the scale of 1:120 and for the neighbouring area of the buildings in the scale of 1:300. The results allowed for creation of snow shape coefficient maps on the investigated areas both for snow precipitation and redistribution for the use of designers, constructors and architects.

2

Snowdrift extent on motorways with busy traffic

Nemchinov M. V., Ivanova A. G.

Structure and Environment

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2018

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Vol. 10, no. 2

122--128

EN

The paper examines the problem of snow-drafts on roads and ways of mitigating them. The results of theoretical analyses of development of snow-drafts and experimental investigations with road models are presented. Authors examined low and high blowing snows with different wind velocities, roads with road bed at terrain elevation and situated on an embankment, with and without snow protective facilities and with variable amount of traffic. Based on the conducted analyses a set of recommendations for snow protection of roads are provided.

PL

W artykule dokonano analizy problemu występowania zaśnieżania dróg oraz opisano sposoby ich ochrony przed tym zjawiskiem. Przedstawiono także wyniki analizy teoretycznej przyczyn zaśnieżania dróg oraz wyniki badań eksperymentalnych z wykorzystaniem modeli dróg. Badano wpływ małych i dużych opadów śniegu występujących przy różnej prędkości wiatru na drogę usytuowaną w poziomie terenu (zero niwelety) i na nasypie, z uwzględnieniem wpływu obecności zasłon przeciwśnieżnych oraz niewielkiego ruchu pojazdów. Na podstawie wykonanych analiz sformułowano zalecenia dotyczące ochrony drogi przed opadami śniegu.

3

Odśnieżanie dachów w świetle dawnych rozporządzeń

Skowron M.

Przegląd Komunalny

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2018

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nr 2

59--61

PL

Gdy zaczyna padać śnieg, zwykle widzimy wokół siebie tylko niepozorny biały puch. Zaczyna on jednak przeszkadzać, gdy utrudnia poruszanie się po chodnikach i ulicach. Rzadko jednak zwracamy uwagę na to, co leży na dachach. A leży tam dużo, nawet bardzo dużo.

4

The features of snow loads on building roofs

Pichugin S. F., Dryzhyruk Y. V., Popovich N. M., Chernetska I. V.

Czasopismo Techniczne. Budownictwo

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2015

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Y. 112, iss. 2-B

441--449

EN

In this paper the probabilistic model of the snow accumulation on the roofs with height discontinuity was worked out, the decreasing coefficient for the snow load weight was received and the ways of their application in the designing were elaborated. The probabilistic model for impulse stochastic process of snowfall sequence was developed. Data from meteorological stations in Ukraine allow determination of statistical characteristics: average annual snowfall amount and exponential distribution of values of one snowfall. The law of intensity distribution of snow melting has been determined experimentally. The territorial zoning map of Ukraine by characteristic values of the snow load on the roofs that emanate heat was developed.

PL

W pracy opracowano probablilistyczny model akumulacji śniegu przy zmianie wysokości dachu, otrzymano współczynnik zmniejszający dla obciążenia śniegiem oraz wypracowano sposoby jego wykorzystania w projektowaniu. Rozwinięto model probablistyczny dla impulsowego procesu stochastycznego dotyczącego opadu śniegu. Dane ze stacji meteorologicznych na Ukrainie pozwoliły określić charakterystyki statystyczne: średni roczny opad śniegu i wykładniczy rozkład wielkości w pojedynczym opadzie śniegu. Prawo rozkładu intensywności topnienia śniegu zostało określone eksperymentalnie. Rozwinięto mapę stref terytorialnych Ukrainy za pomocą charakterystycznych wielkości obciążenia śniegiem dachów wydzielających ciepło.

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Zmienność występowania opadów deszczu i śniegu w Hornsundzie w okresie lipiec 1978 - grudzień 2002

Łupikasza E.

Problemy Klimatologii Polarnej

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2003

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nr 13

93-105

EN

In the polar regions, the sums of precipitation of the accumulation period is of great importance, because they are an component one of the most valid processes connected with glacier mass balance - accumulation. From glaciological point of view, to determine which part of annual sums of precipitation appears in the form liquid and mixed and solid precipitation is the crucial problem. In this connection, the main aim of this paper is analyse variability of the precipitation with respect of their form in the annual course as well as their long-term variability in Hornsund in the period of 1978-2002. The data used in this article are mainly derived from meteorological yearbook Hornsund (2000, 2001) that was published by Institute of Meteorology and Water Management - maritime department in Gdynia and from yearbook Meteorological Conditions Hornsund, Spitsbergen (2001) that was published by Polish Academy of Science in Warsaw. Collected numerical data are not complete. There is a lack of data concerned precipitation sums and meteorological phenomenon for the period from 01sth to 26sth of July 1981. Moreover the data describing precipitation sums does not exist for the days: 04, 07, 09, 19 July 1979. In this article three main form of precipitation (liquid, mixed and solid) were considered. The form of precipitation was determined on the base of meteorological phenomenon that was recorded as current and last weather. The average, maximum and minimum daily air temperatures were additional criterions. In this connection that the notation of meteorological data prevented to consider each event of appearance of precipitation, the days with individual form of precipitation were subjected to analysis. The day with mixed precipitation means that during all 24 hour period (from 6 given to 6 next day) appeared one time snow and second time rain or snow and rain in the same time. The annual course of individual form of precipitation and their probability of appearance in each month, long term variability of sums of individual form of precipitation and the number of days with this form of precipitation in the accumulation and annual periods were discussed. The linear trends and variability coefficients were calculated for long term characteristics of precipitation. It was stated that in Hornsund long-term average sum of annual precipitation amounted at about 424 mm The greatest part of this appear in the liquid (37%) and the lowest in a mixed form. On average in Hornsund there is noted at about 239 days with precipitation in year from what 63% falls on days with snow and 13% on days with snow and rain. In the accumulation period the solid precipitation were characterized by greatest sums as well as greatest number of days with this one. Long-term course of individual form of precipitation shows similar tendencies. In the annual period as well as in the accumulation this one liquid precipitation are characterized by the highest variability coefficient and range of change. Their lowest sums occur in the middle of 80ies and from mid-80ies they show increasing tendency. Mixed precipitation shows the smallest range of change, their highest sums occur in the middle of 80ies and in the case of annual period also in the second half of 90ies. From the second half of 90ies mixed precipitation show decreasing tendency. Statistically significant increasing tendencies of liquid and mixed precipitation during all considered period accompany decreasing tendency of solid precipitation. The highest sums of solid precipitation occur in the first half of 80ies and the lowest one in the second half of the same decade. From the beginning of 90ies there is a decreasing tendency in the course of solid precipitation. During all considered period the solid precipitation dominate as regards number of days with precipitation. The number of days with solid precipitation until the end of 80ies was greater and in the 90ies was lower than long-term average.