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This booklet describes experience gained in the construction of the loam core of the Vilyuiskaya GES Dam in the extremely cold weather conditions of the Far North, including technological operations, use of machinery and equipment, and methods of controlling the quality of soil placement.

Increasing attention is now being given to the provision of modified and controlled relative humidity in buildings for certain occupancies. New considerations are thus introduced in the selection of the humidities to be carried, which must be realistically appraised in terms of need or desirability as well as of the problems which may arise in the provision of them. The severe winter climate in Canada makes it necessary to give special attention to the problems associated with increased indoor humidities during cold weather, not only in the provisions which must be made so that humidities can be maintained, but also in the design of the building enclosure in order to avoid accelerated degradation and increased maintenance. The paper discusses these various considerations and indicates in general terms what must be done when increased indoor relative humidities must be carried in winter.

Certain principles of fire endurance, considering both the thermal and the structural role of different parts and materials of a building, are described. Thermal movements and stresses, restraint in compression and flexural members, the design of supports and fastenings are discussed. Three examples - steel studs, steel joists, suspended ceilings - are used to illustrate how to manage certain problems by applying the principles explained in the paper., Reprinted from: Engineering Digest, April 1970. ISSN: 0013-7901.

Production of gases is an inevitable result of decomposition of organic waste in a sanitary landfill or garbage dump. A principal component of these gases is methane, which is highly flammable. As decomposition is a very slow process, gases will continue to evolve for a very long time. A hazardous condition is created if these combustible gases accumulate in an enclosed area. Construction of buildings over sanitary landfills or reclaimed garbage dumps in general is not recommended. Where such construction is necessary, however, gases can be controlled by proper design, which will include such features as venting of the gases from the fill, the use of a granular material over the fill, the use of an impermeable membrane beneath the floor slab, and the use of forced ventilation, if necessary.

This paper gives a brief history of permafrost investigations in North America starting with the observations of early explorers. In more recent years a concerted attempt has been made to deal with the problems resulting from construction and transportation in permafrost regions. Expeditions down the Mackenzie River led to the establishment of a small research lab. at Norman Wells. The work of the Geological Survey of Canada all over the north is well known. Selection of the new townsite of Inuvik and the new town of Thompson, where a nickel mine is now in operation, are recent projects that have greatly enhanced our engineering knowledge of permafrost beyond what existed when the Alaska Highway and the Hudson Bay railway were built., Permafrost International Conference, November 11, 1963, Lafayette, Indiana, USA, Series: Technical Paper (National Research Council of Canada. Division of Building Research); no. DBR-TP-232

The construction of a two-story steel frame building over permafrost at Churchill, Manitoba, during 1948 to 1950 is described and its performance discussed in relation to the construction techniques used. Its apparent satisfactory performance after nine years of occupancy suggests that the concrete pier and spread footing foundation used can be a practicable alternative to embedded foundations for large heated structures in permafrost regions.

Can building activities go on all year round? In some countries this question does not arise, but in the northern hemisphere it poses a real problem. Before World War II very little attention was paid to it, but in the regions where snow, frost, storm and rain are normal phenomena during a part of the year the building industry has been trying, since 1945, to solve the problem of the usual start- and-stop operation. In this article a Canadian researcher of the Division of Building Research, National Research Council of Canada, Ottawa, tells the story of a successful change in the minds and habits of contractors and workers in his country.

This translation is the sixth from the Russian permafrost publication "Principles of Geocryology", Part II ( Engineering Geocryology). This translation of Chapter XI by A.I. Dement'ev discusses the particular problems of maintaining structures in permafrost areas. Problems associated with keeping the site in good condition are presented first. This is followed by three sections each considering a particular construction method and associated maintenance requirements. The first is concerned with the construction method used to preserve the permafrost condition in the foundation soils, the second allows the permafrost to thaw, and the third disregards the permafrost because it does not affect the structure. The chapter concludes with instructions for releasing the completed structure to the occupants, and suggestions for long-term observations on performance.

Ordinary climatological statistics are of little use to the building designer. Values of the various climatic elements should be selected with frequencies appropriate to the tolerable risks of failure of the structure or one of its functions. For locations without adequate weather records these values must be estimated taking topographical features into account. The effect of cities on the design values is usually small compared to the year-to-year variations., Research into Practice : The Challenge of Application. Proc. 5th CIB Congress: 1971-06, Versailles, France

Wood-frame construction, a system used extensively in Canada for single-family houses, is adaptable to both factory production and on site construction -- the degree of prefabrication being dictated largely by economics. This report discusses the "industrialization" of the wood-frame system through developments in materials and construction techniques and cites cost studies and indices which illustrate changes that are taking place. The role of factory production and mobile homes are briefly reviewed and the impact of research and building regulations on industrialization are considered., Research into Practice: The Challenge of Application. 5th CIB Congress: 1971-06, Versailles, France

This state of the art review summarizes key points of present knowledge in North America and major problem areas relative to engineering design and construction in permafrost regions. Topics discussed include the special importance of proper site selection and investigation, environmental engineering and protection constraints, current concepts of foundation design including footings, piles, ground anchors, foundations near or in water bodies and control of frost heave, design criteria for roads, railroads and airfields, North American experience with dams and reservoirs, excavation and underground construction studies in frozen ground, drainage, groundwater movement and artesian water conditions and problems, difficulties of providing reliable water, waste disposal and other utilities systems at reasonable cost in permafrost regions and the state of the art in the field of petroleum production and pipelines. Areas in which further research and development are required for improvement of engineering design and construction are summarized in a concluding section of the paper., North American Contribution to the Second International Conference on Permafrost, July 1973, Yakutsk, Siberia, USSR