❞ كتاب Building Research Establishment-Geotechnics for building professionals ❝ ⏤ كاتب غير معروف

Biologically

Biology is a natural science that is concerned with the study of life, its various forms and its function, how these organisms interact with each other and with the surrounding environment. The word biology in Greek is made up of two words: bio (βίος) meaning life. And loggia (-λογία) means science or study. Biology: the similarity of vegetation and animal cover on the edges of the African and American states, and the existence of the same fossil.

Branches of biology
Biology is an ancient science thousands of years old and modern biology began in the nineteenth century. This science has multiple branches. Among them are:

Anatomy
Botany
Biochemia
Biogeography
Biofisia
Cytology or cell science
Ecology or environmental science
 

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FOREWORD
Having been Head of the Geotechnics Division at the Building
Research Station from 1972 to 1980, it is a particular pleasure
for me to be invited to write this foreword. Written for the nonspecialist, this book is a distillation of the large reservoir of
expertise, experience and guidance on foundations for low-rise
buildings which has accumulated at BRE over many years. This
experience is based on research into the actual behaviour of
buildings founded on a wide range of difficult ground
conditions, studies of the effectiveness of various ground
treatment methods and detailed examinations of the causes and
severity of damage in hundreds of buildings.
For many, indeed most, building professionals and structural
engineers, geotechnics is something of a black art. The ground
is mysterious: every trench, hole and excavation opened up is a journey into an uncharted
underworld. When problems with foundations occur, rumours abound – underground streams, old
wells, hidden cavities, previous uses of the site and so on. On one occasion, I visited the site of a
foundation excavation in Salisbury, the bottom of which had turned into a soft slurry owing to
upward seepage of water, and was told by an engineer that the whole of Salisbury was floating on
liquid chalk!
Why is it that geotechnics comes across as a mysterious and inaccessible subject? For most building
materials, such as steel, cement, concrete and brickwork, the stiffness and strength can be specified
and remain reasonably fixed and dependable. For soils, however, the stiffness and strength depends
on the stress acting on them and the water pressures acting within them, and these can change
significantly during and after construction. In most cases, the professional cannot specify the
founding material but has to work with what nature has provided; and nature is seldom
straightforward.
To understand the methodology of the geotechnical engineer, it is helpful to compare it with the
approach adopted by a structural engineer or building professional working on an ancient building. A
detailed inspection is essential to discover what materials were used and how the building was
constructed. Special attention is given to detecting signs of weakness and defects since these can
dominate behaviour. Historical records can reveal the history of construction and give important clues
as to the building’s overall response.
This book demonstrates that the geotechnical engineer works in exactly the same way. First, discover
what is there: the ground profile and groundwater conditions at the site and how they vary across it.
For low-rise buildings, highly sophisticated testing is rarely required; it is usually necessary to know
only what the soil types are (fine or coarse material) and how dense they are (density is an indicator
of stiffness and strength). Particular emphasis must be placed on identifying previous uses of the site,
potential hazards and difficult ground. Much can be learned from local experience and records such
as aerial photographs and old maps. Skimping on the investigation can lead to very costly and timeconsuming corrective measures, just as they can for an ancient building. So Chapter 5 Ground
assessment is fundamental to the whole book and is a ‘must-read’.

Biology
Human biology
Who is the founder of biology?
The importance of biology
Areas of work in the field of biology
Theories of biology
Research on biology for the first grade of secondary school
Human biology