什么是隧道
水平或接近水平的地下或水下通道。这种通道被用来采矿,尤其是作为火车或机动车的轨道来引导堤岸附近的江河、埋藏电站等机构的地下设施或引导水源等。古代人用隧道来进行灌溉或运送饮用水,在西元前22世纪,巴比伦人修建了隧道来实现幼发拉底河下的交通。罗马人修建了输水道隧道来用火迅速加热岩石或用水迅速冷却岩石,以使岩石裂开。17世纪开始使用火药爆破後,在岩石开采上有了质的进步。较软的岩石可以用开隧道的方法来实现,用转动的轮子来将物质开采出来并靠传送带运输出去。19和20世纪的铁路运输使隧道的数量和长度得到了很大提高。早期隧道主要用砖石来支撑,而现代隧道则以钢架为支撑,直到混凝土建筑的完成。一般的通道修筑方法包括在开采後立刻喷制混凝土来加固等。
tunnel
Horizontal or nearly horizontal underground or underwater passageway. Tunnels are used for mining, as passageways for trains and motor vehicles, for diverting rivers around damsites, for housing underground installations such as power plants, and for conducting water. Ancient civilizations used tunnels to carry water for irrigation and drinking, and in the 22nd century BC the Babylonians built a tunnel for pedestrian traffic under the Euphrates River. The Romans built aqueduct tunnels through mountains by heating the rock face with fire and rapidly cooling it with water, causing the rock to crack. The introduction of gunpowder blasting in the 17th century marked a great advance in solid-rock excavation. For softer soils, excavation is accomplished using devices such as the tunneling mole, with its rotating wheel that continuously excavates material and loads it onto a conveyor belt. Railroad transportation in the 19th-20th century led to a tremendous expansion in the number and length of tunnels. Brick and stone were used for support in early tunnels, but in modern tunneling steel is generally used until a concrete lining can be installed. A common method of lining involves spraying shotcrete onto the tunnel crown immediately after excavation.
-
桃李不言,下自成行是什么意思?
意思是:古谚语。比喻实至名归。成语名字:桃李不言,下自成行成语发音:táolǐbùyán,xiàzìchéngháng成语解释:古谚语。比喻实至名归。成语出处:晋潘岳《太宰鲁武公诔》:“桃李不言,下自成行;德之休明,没能弥彰。”常用程度:一般成语感情色彩:中性成语成语用法:作宾语、分...
-
王子犯法,庶民同罪是什么意思?
意思是:王子犯了法,和老百姓一样处以罪刑。指王法对于王子、平民是一样的。成语名字:王子犯法,庶民同罪成语发音:wángzǐfànfǎ,shùmíntóngzuì成语解释:王子犯了法,和老百姓一样处以罪刑。指王法对于王子、平民是一样的。成语出处:《野叟曝言》第六七回:“众人都道...
-
战无不胜,攻无不取是什么意思?
意思是:形容军队力量强大,百战百胜。或比喻做任何事情都能成功。成语名字:战无不胜,攻无不取成语发音:zhànwúbùshèng,gōngwúbùqǔ成语解释:形容军队力量强大,百战百胜。或比喻做任何事情都能成功。成语出处:语本《战国策秦策二》:“是知秦战未尝不胜,攻未尝不取,所...
-
奋斗吧中华儿女总导演
奋斗吧中华儿女总导演是杨笑阳。《奋斗吧中华儿女》是庆祝中华人民共和国成立70周年文艺晚会上的音乐舞蹈史诗。该晚会以“奋斗”为主线,全要素运用交响、合唱、舞蹈、朗诵、情景表演等手段,再现一代又一代中华儿女为民族独立、国家富强不懈奋斗的伟大历程。2019...