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Elements of a Building. Types of Foundation

As the demand for land has grown with the growing population natural habitats have become ever more scarce. The areas that remain are under constant pressure for development for intensified farming, industrial complexes, transport, and increased housing and urban expansion. Therefore it has become essential to try to conserve both the habitats and their communities of flora and fauna of these remaining areas. Being given the status of nature reserves has protected many such sites. In order to protect and maintain these areas management plans must be formulated in order to retain, or enhance, the intrinsic features of the sites for which the reserves have been designated.

Throughout much of the populated world, and particularly in Britain, valued sites are most often not truly “natural”, but “semi-natural”. There has been considerable human modification of the landscape, but the plants and animals, which occupy it, are largely derived introduced. As a result most of these sites are the product of the human management of land. Examples include pastures and hay meadows produced by clearing woodland and introducing cutting and grazing regimes, and woodlands managed for centuries by the periodic cutting of regrowth (i.e. coppicing).

In order to retain the interest it is generally necessary to continue the traditional management. It is only on the largest of the nature reserves where conservation managers could consider adopting a policy of non-interference and still expect to find a high proportion of the reserve’s flora and fauna persisting almost indefinitely. This approach has been tried in some of the very largest nature reserves in, for example America and Finland, typically in areas approaching wilderness, little affected by humankind and natural rather than semi-natural. However, most reserves are not large enough, or natural enough to consider non-interference as a viable strategy. Also most conservation managers would argue that a management plan is still essential even if there were a policy of non-interference.

Most management and conservation of protected areas tends to favour the retention of the maximum species diversity which will in turn conserve the greatest variety of gene types, although this will be at the expense of a reduction in numbers of some species. In order to retain species diversity there are a number of costs:

● a reduction in the size of population reduces the size of heterogeneity within species;

● the stabilization of a species population reduces evolution of the species by natural selection;

● management resources must be continually invested to achieve species diversity.

It should also be understood that the maximization of diversity is not necessarily the optimum policy. Consider a species-rich hay meadow. If one ploughs half of it up, and uses it to grow arable crops, there will almost certainly be an overall increase in plant, and probably even in invertebrate diversity. Few hay meadows species would become extinct, and a wide range of ‘weeds’ would appear. Nevertheless this ploughing policy would rarely be advocated, because the stability and complexity of the rare and valued grassland ecosystem would be compromised. Similarly, it would be easy to increase the diversity of a woodland by cutting clearings, creating ponds and marshes by damming streams, and by planting new species. It is quite clear that none of this should ever be done if it is at the expense of the continuity and naturalness of the existing habitat.



The first and primary process in the management of a site for nature conversation is to get to know what habitats and species are on that site and to try to understand its ecology as fully as possible. This means that all the information relevant to that site has to be assembled.

The next process is the appraisal of this information. The appraisal involves both understanding the functioning of the ecosystems present, and also deciding which are the most important nature conservation features, since almost always it is necessary to make choices in management and these choices need to be based on the relative importance of the features to be protected. Other factors may also need to be considered such as the educational and evaluation criteria depending on whether it is an urban or rural site, etc. The resources which it is to devote to managing the site also need to be considered: it is no use advocating extensive management work if there is no labour and no money available.

Once all of this has been done it will be possible to formulate the objectives for the management of the site in order to maintain or enhance the valued features. Also the methods by which the objectives are to be met can be chosen, and also the methods by which the success of the management will be monitored.

The formulation of a written management plan is an effective and comprehensive way in which all these targets can be met and by which continuity and stability of management can be ensured.

If conversation management is to succeed in protecting biological diversity there is a real need for knowledge to be shared. Therefore the production of a working guide for the writing and recording of a management plan is important.

THE PURPOSE OF A MANAGEMENT PLAN

The primary aim of a management plan for a nature reserve must be to protect and conserve as much as possible of the nature conservation interest present. There are, however, a number of functions of a management plan:

● to provide a full description of the site utilizing the available data

● to provide a site evaluation against recognized standards

● to identify clear objectives and purposes for managing the site based on objective criteria

● to identify potential methods to achieve the objectives

● to enable planning of resources and manpower

● to anticipate conflicts and problems regarding the site

● to identify monitoring procedures

● to ensure the continuity of effective management of the site, especially if there are changes in personnel; a plan can help to inform and control a transient workforce

● to facilitate communication between sites, organizations, local authorities, public, etc., and draw together different interest groups

● to act as a reference document and historical record. A management plan should be considered as a working document to be used on regular basis and to be updated as and when further information becomes available.

It is of course possible to write management plans for sites which are not primarily nature reserves – country parks, public open spaces, etc. – but the objectives associated with public use can be fully taken into account.

(Sustainable Development of Industrial and Urban areas. Student Manual for BSc and MSc students. Wydawnictwo Uniwersytetu Śląskiego Katowice, 2000)

 

 

BIBLIOGRAPHY

1 ABBYY Lingvo 6.0. Ñèñòåìà ýëåêòðîííûõ ñëîâàðåé, 1989-1999.

2 Adams, Ansel Easton. The Tetos and the Yellowstone, Five Associates, 1970.

3 An Outline of American Geography. United States Information Agency, USA, 1997.

4 Belt, Don. The World’s Great Lake. National Geographic, ¹ 2, 1998.

5 Bryant, Richard H.. Physical Geography Made Simple, Oxford, 1993.

6 Dictionary of Contemporary English. Longman, Barcelona, 2000.

7 Dictionary of English Language and Culture. Longman, 2003.

8 Encyclopaedia Britannica 2007. Deluxe Edition. Sun Microsystems, Inc.

9 English Dictionary for Advanced Learners, Macmillan, London, 2002.

10 Farmer, N. The Encoaching Desert. London, 1990.

11 Garton-Sprenger, Judy & Greenall, Simon. BBC Beginner’s English. BBC English by Radio and Television, London, 1990.

12 Hopkins, D. and Nettle, M. Passport to IELTS, London, 2003.

13 Hornby, A.S. Advanced Learner’s Dictionary. Oxford University Press, 1995.

14 Hornby, A.S. Oxford Advanced Learner’s Dictionary of Current English. Oxford, 1995.

15 Jordan, R.R. Academic Writing Course. Pearson Education Ltd, England, 2002.

16 Keating, Bern. The Mighty Mississippi. National Geographic Society, 1971.

17 Longman Dictionary of Contemporary English. Pearson Education Limited, England, 2003.

18 Longman Language Activator. Longman, London, 2002.

19 Norris, Roy. Ready for First Certificate. Macmillan, Oxford, 2005.

20 Oxford Minireference Dictionary and Thesaurus. Oxford University Press, 1996.

21 Sharman, Elizabeth. Across Cultures. Longman, 2004.

22 Shenandoah NP, Va, National Park Service, US Department of the Interior, 1996.

23 Spurgeon, Richard. Ecology. Usborne Publishing Ltd, Usborne House, London, 1994.

24 Sustainable Development of Industrial and Urban areas. Student Manual for BSc and MSc students. Wydawnictwo Uniwersytetu Śląskiego Katowice, 2000.

25 Vaugham-Rees, Michael. In Britain, “Chancerel”, London, 1995.

26 Waugh, David. Key Geography for GCSE. Stanley Thornes (Publishers), England, 1995.

Elements of a Building. Types of Foundation

 

The first houses were built for the purpose of protecting their owners from the weather and, therefore, were very simple - a roof to keep off the rain or snow, and walls to keep out the wind.

The buildings erected now can be divided into two broad classifications: they are either for housing or for industrial purpose.

As far as the material is concerned, the building can be divided into stone (or brick), wood and concrete types. The brick is an artificial material made of clay then burnt to harden it. The natural stone is used for footing and foundations for external walls carrying the load. The buildings made of stone or brick are durable, fireproof and have poor heat conductivity.

Materials and structural forms are combined to make up the various parts of a building, including foundations, load-carrying frame, skin and interior constructions. The building also has mechanical and electrical systems, such as lifts and escalators, heating and cooling systems, and lighting systems.

A building has two main parts, the substructure (the part below ground) and the superstructure (the part above ground). The substructure is usually called the foundation. It includes the basement walls, even though these may extend above the ground.

Both the substructure and the superstructure help to support the load (weight) of the building. The dead load of a building is the total weight of all its parts. The live load is the weight of the furniture, equipment, stored material, and occupants of a building. In some regions, the wind load of a building is important if the structure is to withstand storms. The snow load and earthquake shocks may also be important factors.

Foundations are the chief means of supporting a building. They carry both the dead and live loads. There are four main types of foundations: (1) spread, (2) pier, (3) pile, and (4) mat or raft.

Spread foundations are long sections and rectangular slabs of reinforced concrete that extend beyond the outer edges of the building and under its walls and columns. Such foundations are not so firm as those based on solid rock. The footing areas in contact with the soil must be of sufficient size to spread the load safely over the soil and to avoid excessive or uneven settlement that would cause walls to crack or doors to bind.

Pier foundations are heavy columns of concrete that go down through the loose topsoil to a bed of firm rock. This bed may also be sand, gravel, or firm clay. If the bed consists of firm clay, the pier is usually belled out (enlarged) at the base, to increase the bearing area.

Pile foundations are long, slender columns of steel, concrete, or wood. Machines called pile drivers

hammer them down as deep Pic. 2 Most skyscrapers are built on rock and

as 200 feet (61 meters) to a have pile foundations and skeleton frameworks

layer of solid soil or rock.

These columns transmit the building load to the supporting soil. Most skyscrapers are supported by rock foundations.

Mat foundations, also called raft foundations, are thick slabs of reinforced concrete that span the whole area beneath a building. They are normally used in poor soil conditions where it is not possible or economical to drive piles or piers down to good soil or rock. In effect, they enable the building to "float" on the soft soils.

 

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Date: 2014-12-22; view: 1351


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