Mechanics in XXI century

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Здесь приводятся наиболее яркие достижения в области механики за годы, прошедшие с начала третьего тысячелетия.

Achievements on planet Earth

• On August 1st, 2012 the Russky Bridge was opened in Vladivostok. The main bay of the bridge reaches 1104 meters in length which makes the bridge to be the longest among cable-stayed bridges in the world. Before the bridge was built Sutong Yangtze River Bridge (China) was the longest. Construction of the bridges from early ages defined technology level of countries where the bridges were built. It required deep knowledge of mechanics in order to construct them. It is easy to recall several catastrophes due to incorrect analysis of the brides’ structures. The examples are The Tay Bridge disaster in 1879 (UK) Tacoma Narrows Bridge disaster in 1940 (USA). In both cases the catastrophe occurred due to incorrect dynamic analysis of the bridge subjected to wind loading.

• On January 4th, 2010 The Burj Khalifa was opened in Dubai, UAE. Its height equals 828 meters which makes it the tallest structure in the world. Before the skyscraper was built the tallest structure was Warsaw radio mast which collapsed in 1991. The signifcant height of the structure required solving a number of complex mechanical problems among which were insuring structure’s stability, resistance to the wind loading, construction of high altitude elevators and water supply system.

• On January 5th, 2005 a group of American austronauts discovered Eris which is a dwarf planet situated farther than the orbit of Pluto. Eris’ weight and size exceed the weight and size of Pluto. The discovery together with the discoveries of a number of smaller objects with the size compared to Pluto’s size that were happening in 2000-2005 lead to rethinking of what a planet was and how the Solar System was organized. As a result, Pluto lost its status of a planet and together with similar to it objects was classified as a dwarf planet. The number of planets in Solar System decreased to 8. It is worth noting that the way plantes orbit the sun is entirely mechanical problem the solution to which actually helped to discover the 8th planet, Neptune.

• On October 22th, 2014 an article by British and Russian scientists (Novoselov et al. 2004) was published in the journal Science which reported the purely mechanical creation of graphene - two-dimensional material comprising a single layer of carbon atoms. In 2010 two of the authors of article, Geim A.K. and Novoselov K.S. were awarded the Nobel Prize in Physics for "groundbreaking experiments with two-dimensional material - graphene." The existence of two-dimensional materials was considered impossible before. Graphene has a unique mechanical properties - its rigidity and strength superior to all known materials. In addition, being essentially a two-dimensional material, it allows you to take a fresh look at the theory of plates and shells, which were previously primarily treated as approximate theory to describe three-dimensional objects.

• On December 3th, 2001 American inventor Dean Kamen introduced Segway - electric vehicle, in which a person moves in a standing position. The device has two wheels arranged on either side of the driver, the vertical position stabilization of human performed by a system which regulates the speed of rotation of the wheels. Segway is similar to the Kapitza's pendulum - a pendulum, which vibration stabilized in an unstable vertical position and a mathematically investigated the first time by Academician Kapitsa P.L. (Kapitsa, 1951). Segway with a driver on the road takes a little more space than an ordinary pedestrian, but can move at speeds up to 20 km / h over rough terrain, the battery provides a mileage of about 40 km. Over the past decade Segway has received fairly widespread in the tourism sector, in some countries Segways are used by the police. Widespread of segways hinders their relative high cost, however, it is clear that the development of this problem will be solved by technology.

Achievements in space

• On August 6th, 2012 The Mars rover Curiosity (USA) is safely delivered to the surface of Mars, that has served as the beginning of a new research mission on Mars. Curiosity can call full-fledged laboratory on wheels (weight of 900 kg), the robot of the similar size and complexity never before studied other planets. There is on its board also the Russian equipment.
• On October 9th, 2009 As a result of a shock experiment the LCROSS has found water ice in the polar region of the Moon. Availability of water on the Moon does possible her future colonization by the person.
• On May 25th, 2008 The spacecraft Phoenix (USA) has made landing in the polar region of Mars. The conducted researches have allowed to find water ice under a layer of earth. Availability of water testifies to a possibility of existence of live organisms on Mars in the past, and, perhaps, and the present.
• On January 14th, 2005 spacecraft Huygens has made landing to the surface of Titan, the largest satellite of Saturn. It has been established that on the surface of Titanium, under a thick layer of the atmosphere, there are rivers and lakes from liquid methane. It has served promotion of a hypothesis of a possibility of existence of life on the Titan on the basis of methane (instead of water) and hydrogen (instead of oxygen).
• On January 4th and 25th, 2004 Mars rovers, Spiritand and Opportunity (США) are delivered to the opposite sides of Mars. During the movement on the red planet, mars rovers researched its surface and composition of the atmosphere, transferring data and high-quality photos to the earth. Results of researches, in particular, have confirmed existence in the past of liquid water on Mars.

Антидостижения XXI века

• 8 июля 2011 года состоялся последний старт по программе «Спейс Шаттл». В настоящее время Россия остается единственной страной, выполняющей пилотируемые полеты на Международную космическую станцию. Программа полетов шаттлов была сильно подорвана гибелью шаттла Колумбия 1 февраля 2003 года, разрушившегося при входе в атмосферу. Причиной катастрофы послужило нарушение теплозащитной поверхности челнока, вызванное падением на него куска теплоизоляции кислородного бака при старте корабля.

• 26 ноября 2003 года состоялся последний полет «Конкорда», чем была завершена эра гражданской сверхзвуковой авиации. Катастрофа, приведшая к гибели «Конкорда» 25 июля 2000 года при вылете из парижского аэропорта «Шарль де Голль» стала одной из основных причин прекращения эксплуатации «Конкордов». Катастрофа произошла в результате наезда колеса шасси на металлический обломок, случайно оказавшийся на взлетной полосе, что привело к повреждению обшивки, утечке топлива и возгоранию.

• 11 сентября 2001 года в результате беспрецедентного теракта был разрушен Всемирный торговый центр (ВТЦ) в Нью-Йорке. В высочайшие небоскребы Нью-Йорка, башни-близнецы ВТЦ на полной скорости врезались управляемые террористами гражданские самолеты Боинг 767. Башни выдержали удар самолетов, однако возникший в них пожар привел к обрушению зданий менее чем через два часа после столкновения. Причиной разрушения явилось то, что несущие стальные колонны начали изгибаться под действием высокой температуры и перераспределившейся нагрузки, из-за чего был превышен предел прочности материала колонн. В результате началось обрушение верхних этажей, породивших цепную реакцию — здания сложились по принципу карточного домика. Только спустя 5 лет началось строительство новых зданий на территории ВТЦ.

См. также

• Новости науки и техники
• Механика на стыке с другими областями знаний
• Механика

Ссылки

• Список новых перспективных технологий
• Популярная механика (интернет-портал и сайт журнала).
• Timeline of scientific discoveries
• Ten science stories that changed our decade
• The 7 Greatest Scientific Achievements Of The Last 50 Years