【正文】 of the institution of civil engineers to clarify the definition of) it includes construction engineering, bridge engineering, underground engineering, road and railway engineering, port, Marine and environmental engineering, water supply and drainage, disaster prevention and mitigation and many other engineering involves the content can be is closely related to , agriculture, transportation, munication, education and other undertakings, is inseparable from the civil as factories, mines, railways, highways, Bridges, shops, homes, hospitals, schools, such as irrigation and water conservancy project construction, generally referred to as the basic construction of place is civil engineering directly with the people of the food, clothing, shelter, line are closely related, is one of the oldest subjects, but it is acpanied by the development of other related disciplines, deepening the needs of economic construction and social progress, continue to expand.【Conclusion】Civil engineering is a broad discipline, its various infrastructure and social engineering level and importance of the first is that it is the country39。s surface to 30 m more shallow construction of underground the development of economy, foreseeable underground engineering in our country will enter the booming period.Modern underground engineering is developing rapidly, all kinds of typical engineering famous world has hundreds of cities built underground developed countries, and gradually to underground mall, underground parking, underground railway, and blends into underground pipelines, etc, bee a multifunctional underground plex.Railway engineeringRailway engineering originally included railway related civil (subgrade, rail, bridge, tunnel, station), mechanical (lootive, vehicle) and the signal and other the development of the construction and technology further division of labor, some engineering gradually formed an independent subject, such as the lootive, vehicle engineering, signal engineering。s highway construction has obtained the good result.15 the first three years, highway construction investment as a share of GDP keep in ~ %, investment grew by an average of 17% a year.Highway construction in the following characteristics: the country more than half of the province of more than 1000 km highway road mileage of 46000 kilometers, the total mileage of million kilometers。Also refers to the object of engineering construction, building on the ground or underground, on the road or water, directly or indirectly for human life, production, military, scientific research services of all kinds of engineering facilities, such as houses, roads, railways, pipelines, tunnels, Bridges, canals, DAMS, ports, power stations, the offshore platform, water supply and drainage, and protective engineering, etc.The classification of civil engineeringTo build a project facilities generally go through survey, design and construction of the three phase, need to use engineering geological survey and hydrogeological survey, engineering surveying, soil mechanics, engineering mechanics, engineering design, construction materials, construction equipment, engineering machinery, building economic disciplines and knowledge in the field of construction technology, construction organization, as well as the electronic puter and mechanical testing wide in civil engineering is a prehensive the progress of science and technology and the development of engineering practice, the civil engineering discipline connotation also has developed into a broad category, large, plex integrated system.Civil engineering technology are mainly relies on the development of engineering practice rather than relying on scientific experiments and theoretical studies, for two reasons: one is some objective conditions are too plex, diffi