Multi-storey Apartment Houses Research Articles

Radon concentration in conventional and new energy efficient multi-storey apartment houses: results of survey in four Russian cities

During last decades, energy saving in new buildings became relevant within the energy efficiency strategies in various countries. Such energy efficient building characteristics as air tightening and low ventilation can compromise indoor air quality, in particular, increase radon concentration. In Russia, a significant part of the new buildings is the energy efficient multi-storey apartment houses. The aim of this study is to assess the significance of possible radon concentration increase in new energy efficient buildings in comparison with typical conventional multi-storey houses of previous periods. Radon surveys were conducted in Russian cities Ekaterinburg, Chelyabinsk, Saint-Petersburg and Krasnodar. The radon measurements were carried out in 478 flats using CR-39 nuclear track detectors. Energy efficiency index (EEI) was assigned to each house. All buildings were divided into six main categories. The smallest average radon concentration was observed in panel and brick houses built according to standard projects of 1970–1990 (four-city average 21 Bq/m3). The highest average radon concentration and EEI were observed in new energy efficient buildings (49 Bq/m3). The trend of radon increase in buildings ranked with high EEI index is observed in all cities. The potential increase of radiation exposure in energy-efficient buildings should be analyzed taking into account the principles of radiological protection.

Thin-walled shell foundations

The article presents a study of the interaction of strip foundations of multistorey apartment houses united by flat cylindrical shells with a ground base. The foundation of a 17-storey residential building has been taken as an example. The ground base consists of strong upper and highly compressible underlying layers. The use of traditional foundations under the specified conditions is hardly possible. The calculation scheme of the building and the stages of the ground foundation work are represented. Also, the researchers share the results of geotechnical monitoring in the construction process including observations of settlings at 25 points with an accuracy of 0.1 mm and measurement of layer-by-layer deformations of the ground base under the building to a depth of 10 meters from the surface. The diagrams demonstrate the actual settlement of the building with increasing load and layer-by-layer deformations of the ground base in depth are presented.

Daugiabučių namų kvartalų modernizavimo strategijų analizė

Straipsnyje nagrinėjamas daugiabučių gyvenamųjų namų kvartalo modernizavimas. Didelę visų pastatų dalį sudaro daugiabučiai, todėl jų atnaujinimas yra aktuali problema visose šalyse. Vokietija turi nemažą gyvenamųjų namų modernizavimo patirtį, kurią galima pritaikyti ir Lietuvoje. Kad modernizavimas būtų kuo efektyvesnis, daugiabučius reikia atnaujinti ne po vieną, bet kompleksiškai modernizuoti visą kvartalą. Šiame straipsnyje analizuojamos Vokietijoje, Berlyne, esančio Hellersdorf rajono modernizavimo strategijos: ilgalaikė renovacija ir pastatų valdymas; butų pasiūlos diferenciacija siekiant stabilizuoti mišrią socialinę struktūrą; miesto centro kaip funkcionalios miesto dalies stambiaplokščių namų rajone sukūrimas; gyvenimo standartų ir kokybės pagerinimas; gyvenamųjų namų integravimas į natūralią vietovę; demokratinis planavimo procesas; partnerių pasirinkimas.

Ventilation through building walls — wind tunnel studies

Abstract The usual way of extracting the waste air in a multi-storey residential building is to conduct the air above the roof. The purpose of this research program was to examine whether exhaust air from each apartment could be discharged outdoors via exhaust vents mounted on the outer wall in such a way that no odours or other harmful effects are caused. This would facilitate the use of apartment-based mechanical ventilation using wall ventilators which would be of great help specially in renovating old multi-storey apartment houses. A wind tunnel investigation was carried out using tracer gas measurements with models of three multi-storey buildings to determine how much waste air from a wall outlet is carried into the intakes on the same wall. Also full-scale experiments were performed and for comparison some of full-scale test wind conditions were reproduced in wind tunnel tests. Several parameters were varied in wind tunnel investigations, for example: exhaust jet-to-wind velocity ratio, the distance between outlet and intake openings and the position of the wall outlet. The results showed that the exhaust jet-to-wind velocity ratio is a suitable parameter for determining dilution rates and the tests can be carried with different absolute velocity values. Owing to the turbulence caused by the building itself and near-by buildings the trajectories of the exhaust plumes are much more complicated with wall ventilators than with roof ventilators. Near exhaust vents on the open wall, the measured dilution was usually much more higher than that predicted by the minimum dilution theory for roof exhaust. Thus, the theory could be useful when dimensioning exhaust vents on an open wall. In niches and corners the theory does not function reliably.

The Distribution of the Multi-storey Apartment Houses in Sendai

The author investigated the distribution of the multi-storey (three or more storey) apartment houses in Sendai and adjacent cities, Izumi and Natori, classifying them into three types, company or official, private, and public apartment houses. Also, he surveyed the changes in the distribution during the last fifteen years, and examined some of the characteristics of the three types of houses respectively.The results of this study are as follows:1) The number of multi-story apartment houses have increased greatly in the last fifteen years; however, they still constitute a small share of residential dwellings. And the high-rise apartment houses have increased in recent years.2) There are many multi-storey company of official apartments in the residential areas of the city. These houses are owned mainly by governmental, finaincal, and construction- industrial institutions, reflecting the changing function of Sendai as an administrative city of Tohoku.3) The number of multi-storey private apartment houses have increased very rapidly in recent years, especially around the C. B. D. Many of dwellers of these apartment houses benefit because of the close proximity to their working places. Also, a part of these buildings is often used as offices or stores.4) Many multi-storey public apartment houses are located in the suburbs in large clusters. This type of apartment complex is usually constructed on public land or on the land where public buildings existed in the past.