Nauka 50: Nano (Svibanj 2024)
Građevinarstvo, struka projektiranja i izvođenja građevinskih radova koji služe široj javnosti. Izraz se prvi put koristio u 18. stoljeću za razlikovanje novopriznate profesije od vojnog inženjerstva, do tada važne. Međutim, od najranijih vremena inženjeri su se bavili mirnim aktivnostima i mnogim građevinskim radovima iz starih i srednjovjekovnih vremena - poput rimskih javnih kupališta, puteva, mostova i akvadukata; Flamanski kanali; nizozemska morska obrana; francuske gotičke katedrale; i mnogi drugi spomenici - otkrivaju povijest inventivnog genija i upornog eksperimentiranja.
Povijest
Počeci građevinarstva kao zasebne discipline mogu se u Francuskoj osnovati 1716. godine Most i autoceste, od kojih je 1747. godine izrastao École Nationale des Ponts et Chaussées („Nacionalna škola mostova i autocesta“). Njeni učitelji napisali su knjige koje su postale standardna djela mehanike materijala, strojeva i hidraulike, a vodeći britanski inženjeri naučili su ih francuski čitati. Kako su dizajn i proračun zamijenili pravilo i empirijske formule, a kako su stručna znanja kodificirana i formulirana, ne-vojni inženjer prešao je na prednji dio pozornice. Talentirani, ako često samouci, majstori, kamenjari, mlinari, proizvođači alata i proizvođači instrumenata postali su građevinski inženjeri. U Britaniji je James Brindley započeo kao vjetrovit i postao najveći graditelj kanala stoljeća;John Rennie bio je miljenički učenik koji je na kraju izgradio novi londonski most; Thomas Telford, klesar, postao je vodeći britanski graditelj cesta.
John Smeaton, prvi čovjek koji se zvao inženjer građevine, počeo je kao proizvođač instrumenata. Dizajn svjetionika Eddystone (1756.-59.), Zajedno sa zidovima koji se isprepliću, zasnovan je na iskustvu majstora. Smeatonov rad potpomognut je temeljitim istraživanjima i njegove su usluge bile tražene. 1771. osnovao je Društvo građevinskih inženjera (danas poznato kao Smeatonsko društvo). Njegov je cilj bio okupiti iskusne inženjere, poduzetnike i pravnike kako bi promovirali izgradnju velikih javnih radova, poput kanala (i kasnije željeznice), i osigurali parlamentarne ovlasti potrebne za izvršavanje njihovih programa. Njihovi su se sastanci održavali tijekom zasjedanja parlamenta; društvo slijedi ovaj običaj do danas.
The École Polytechnique was founded in Paris in 1794, and the Bauakademie was started in Berlin in 1799, but no such schools existed in Great Britain for another two decades. It was this lack of opportunity for scientific study and for the exchange of experiences that led a group of young men in 1818 to found the Institution of Civil Engineers. The founders were keen to learn from one another and from their elders, and in 1820 they invited Thomas Telford, by then the dean of British civil engineers, to be their first president. There were similar developments elsewhere. By the mid-19th century there were civil engineering societies in many European countries and the United States, and the following century produced similar institutions in almost every country in the world.
Formal education in engineering science became widely available as other countries followed the lead of France and Germany. In Great Britain the universities, traditionally seats of classical learning, were reluctant to embrace the new disciplines. University College, London, founded in 1826, provided a broad range of academic studies and offered a course in mechanical philosophy. King’s College, London, first taught civil engineering in 1838, and in 1840 Queen Victoria founded the first chair of civil engineering and mechanics at the University of Glasgow, Scot. Rensselaer Polytechnic Institute, founded in 1824, offered the first courses in civil engineering in the United States. The number of universities throughout the world with engineering faculties, including civil engineering, increased rapidly in the 19th and early 20th centuries. Civil engineering today is taught in universities on every continent.
Civil engineering functions
The functions of the civil engineer can be divided into three categories: those performed before construction (feasibility studies, site investigations, and design), those performed during construction (dealing with clients, consulting engineers, and contractors), and those performed after construction (maintenance and research).
Feasibility studies
No major project today is started without an extensive study of the objective and without preliminary studies of possible plans leading to a recommended scheme, perhaps with alternatives. Feasibility studies may cover alternative methods—e.g., bridge versus tunnel, in the case of a water crossing—or, once the method is decided, the choice of route. Both economic and engineering problems must be considered.
Site investigations
A preliminary site investigation is part of the feasibility study, but once a plan has been adopted a more extensive investigation is usually imperative. Money spent in a rigorous study of ground and substructure may save large sums later in remedial works or in changes made necessary in constructional methods.
Since the load-bearing qualities and stability of the ground are such important factors in any large-scale construction, it is surprising that a serious study of soil mechanics did not develop until the mid-1930s. Karl von Terzaghi, the chief founder of the science, gives the date of its birth as 1936, when the First International Conference on Soil Mechanics and Foundation Engineering was held at Harvard University and an international society was formed. Today there are specialist societies and journals in many countries, and most universities that have a civil engineering faculty have courses in soil mechanics.
Design
The design of engineering works may require the application of design theory from many fields—e.g., hydraulics, thermodynamics, or nuclear physics. Research in structural analysis and the technology of materials has opened the way for more rational designs, new design concepts, and greater economy of materials. The theory of structures and the study of materials have advanced together as more and more refined stress analysis of structures and systematic testing has been done. Modern designers not only have advanced theories and readily available design data, but structural designs can now be rigorously analyzed by computers.
