GEOLOGICAL ENGINEERING 39 geological features Under such circumstances, a consultation with engineering geologists or geological engineers is desirable In many countries the term ‘ground engineering’ is used whenever soil mechanics or rock mechanics principles are employed in actions that modify the properties of naturally occurring materials Usually these actions are directed toward making the materials stronger (i.e capable of supporting larger structural loads) or reducing the permeability (e.g to reduce the inflow of water into an excavation) These disciplines (geological engineering, engineering geology, environmental geology, geotechnical engineering, and ground engineering) are frequently involved with construction sites, especially those for large and highly visible projects, and within or near large urban centres Such applications lead to the use of two additional terms related to these typical locations: ‘construction geology’ and ‘urban geology’ (see Urban Geology) In summary, geological engineering refers to a particular style of engineering that is predominantly engineering by training and experience, but utilizes special additional knowledge of geology Geological engineers can perform a variety of tasks in the resource exploration and production fields, but in recent times most individual geological engineers are employed on civil engineering and environmental projects They frequently work closely with engineering geologists, hydrogeologists, and geotechnical engineers, and there is in fact a continuum in training, experience, and background among individuals following these career paths All such individuals may be employed in environmental geology, hydrogeology, or ground engineering projects and may further specialize in particular types of project that may be referred to as ‘construction geology’ or ‘urban geology’ Historical Interactions Between Civil Engineering and Geology Geologists and engineers have interacted with varying degrees of support and antagonism for over 200 years The industrial revolution demanded the transport of large quantities of heavy goods, first by canals and then by railways When constructing civil works by large gangs of men using little more than picks, shovels, and wheelbarrows, the engineers had a considerable interest in exactly what they would be excavating, and how difficult the work might be William Smith (1769–1839), during his surveys for and construction of the Somerset Coal Canal near Bath in southwestern England, noted the regular succession of strata, and was able to correlate them with those in other locations by the use of fossils (see Famous Geologists: Smith) In 1799 Smith coloured his geological observations on a map of the Bath area: the oldest geological map in existence! In the same year Smith wrote a document, Table of Strata near Bath, and for this he became known as ‘The Father of English Geology’, although he continued to refer to himself as a civil engineer In 1801, and subsequently in 1815, Smith produced further geological maps of England and Wales He also conducted numerous civil engineering and geological investigations, and continued to assert the importance of geology to engineering Alexandre Collin, a French engineer responsible for the construction of several canals, conducted extensive field surveys to determine the characteristics of slope failures of cuttings and embankments His 1846 treatise on the stability of clay slopes recognized that the characteristic circular failure surfaces were the result, not the cause, of the landslide movements Even more importantly, he undertook laboratory experiments to determine the shear strength of these materials He basically invented the subject of soil mechanics long before it became a popular civil engineering discipline Unfortunately, his writings were poorly distributed and were largely ignored until about 100 years later The railways also required considerable earthworks and encouraged an ongoing close cooperation, and friendly relationship, between civil engineers and geologists during the latter half of the nineteenth century The minutes of many meetings and the subjects of public lectures provide ample evidence of this collaboration – as, for example, the following quotation from an 1841 meeting of the Institution of Civil Engineers in London: ‘‘Mr Sopwith called the attention of the meeting to the valuable Geological Sections presented by the railway cuttings the crops of the various seams of coal, with the interposing strata, were displayed in the clearest manner, developing the geological structure of the country which the railway traverses.’’ Beginning in the 1890s, the former close association of geology (and geologists) and civil engineering (and civil engineers) broke down The introduction of powered machinery began to change the perceptions of many engineers, any job became feasible and ‘successes’, such as the completion of the Panama Canal by American engineers using much more powerful equipment (and also superior medical knowledge concerning tropical diseases) after the earlier failure of the French, merely served to increase this ‘can do’ attitude A minority of engineers continued to strongly recommend that their colleagues seek geological advice Chief among them in this period was Karl Terzaghi, ‘The Father of Soil Mechanics’ who strongly supported the linkage between of geology and engineering