What is mechanics?

To answer this question, we must grasp it from its historical development process. There was also the word "mechanics" in ancient China, but just as "science" in ancient China was just the study of imperial examinations, it has a completely different meaning from now. In ancient China, "mechanics" meant studying hard. For example, Farming Mechanics should be taught through hard work. The modern meaning of "mechanics" was introduced from the west. Although there was no word with the same modern meaning in ancient China, the word "force" appeared quite early. In Oracle Bone Inscriptions, the word "force" is the shape of a slave bending over to farm. Indicates that its capacity is full.

China's earliest definition of "force" was written by Mozi (490-405 BC) in Mo Jing. There are two opinions: first, "force is heavy." Second: "The strong, the punishment is exciting." The "punishment" here is universal. According to these two statements, it is not far from "forcing" now.

In ancient technology, whether in the east or the west, a considerable part is lifting and handling, that is, resisting gravity. Therefore, in a long historical period, the main content of mechanics is the study of statics, balance, center of gravity and lift.

On the other hand, "force" is the reason why an object changes its state of motion. This is Galileo's later understanding. According to the present literal understanding, the second statement in Mo Jing seems to be that "shape" refers to the body, and "strength" refers to movement, that is, force is the reason why objects move. Unfortunately, in Mohist Scripture, shape refers to the body, which means to lift it up. According to the Mohist scripture itself, "it is exciting to lift weights easily", so it can be seen that Mohist scripture means that strength means that the body lifts things upward. Therefore, the two statements in the Mohist Scripture have only one meaning, only silence does not move.

In the west, the word "mechanics" comes from Greek. Literally, it means invention, originality and machinery. Later, it gradually enriched and evolved into a word, which has two meanings, namely, the improvement of all technologies and the rational discussion of the laws of natural motion, and the deeper meaning developed late.

From the perspective of engineering technology, human beings have gradually accumulated knowledge about center of gravity, balance, simple machinery, buoyancy, circular and linear motion. From ancient times, the Sumerians invented the wheel in 5000-4000 BC, the canoe in 2000 BC in China, and the boat and sailboat in 2500 BC in Egypt. These experiences gradually accumulated, from ancient Greece to ancient Greece, there were guarding city equipment similar to Archimedes to construction machinery in Vitruvi (1 century ago park) in Italy.

Until the17th century, the accumulated mechanical knowledge was summarized into five simple machines (lever, shaft, inclined plane, screw and pulley). In western languages, Mechanics and Mechanism are the same root. Therefore, in a long historical stage, people regarded mechanics and machinery as one thing.

From the perspective of exploring the laws of nature, human beings first accumulated the observation data of celestial motion and tried to explore its real motion state. The early development of mechanics is inseparable from astronomy, from the ancient calendar to the Ptolemaic geocentric theory of ancient Greece, and then to the classical mechanics of Copernicus, Galileo, Kepler and Newton. This exploration is closely combined with mathematics.

Later, these two trends combined to form the discipline of mechanics. Its research content and characteristics also change with the development of the times.

Leonardo da vinci, a scholar in the early European Renaissance, said: "Studying hard is a paradise for mathematical science, because we get the results of mathematics here."

Galileo, an Italian scholar, said in "Dialogue on Two New Subjects" (that is, mechanics of materials and the theory of motion of objects): "Your Venetians' continuous activities in famous arsenals, especially those involving mechanics, have provided a broad field for studious people. Because in this department, all kinds of machines and instruments are constantly manufactured by many craftsmen, some of them must have high skills and be very clever in explaining problems, because they have inherited experience and used their own observations.

At the end of Ming Dynasty in China, almost at the same time as Galileo, the definition of mechanics was roughly reflected in the western understanding of mechanics at that time in the dictation of the western missionary Deng (Swiss), the record of Wang Hui, and the Atlas of Wonders in the Far West published by 1627. The book says: "Strength is strength, strength. Such as manpower, horsepower and wind power. Also called exertion, such as manpower, horsepower, water and wind. Art is a clever way and means to exert itself, so it is famous for making good use of its power and saving it lightly. Emphasize that scholars, learning is nominal, art is private, literature, science, arithmetic and so on are all called learning, so they are called public. However, the study of this skill is unique and heavy, so learning clouds is important. "

This passage explains the origin of the two names: emphasizing learning (that is, mechanics) and strengthening art (that is, mechanics). It can be seen that the early research content of mechanics is generally inseparable from lift, whether in the East or in the West.

The book also says: "Every school has its own branch. For example, when medical schools deal with human diseases, it is necessary to count the number of statisticians. But regardless of soil, water, wood, stone and other things, the division of this art always carries a heavy load. " This article summarizes the research contents of mechanics.

When talking about the relationship between mechanics and mathematics, the book says: "The creator's creations are counted, measured and weighted, and everything is natural. Numbers are not only arithmetic, but also measurement, and it is also important to learn this skill. There is a heavy nature. If one is more important than the other, then this is an arithmetic problem; The size of an object heavier than a heavier object is called a measure. Therefore, it is necessary to learn mathematics, learn mathematics and learn again. Gai Sanxue was born spontaneously, and he is a brother in law and cannot be separated. " Mathematics here refers to calculation, which is different from modern mathematics. Metrology refers to measurement, and more broadly, to geometry.

The most representative thing is that Newton said in the preface of Scientific Principles of Natural Philosophy: "The whole task of philosophy seems to be to study various forces of nature from various moving phenomena, and then use these forces to demonstrate other phenomena." All natural phenomena can be demonstrated by similar reasoning according to mechanical principles.

Newton said in the preface of the first edition of his book Scientific Principles of Natural Philosophy: "Because the ancients (such as Pappus (3rd century BC) told us) regarded mechanics as the most important thing to study natural things, now people try to explain natural phenomena with mathematical laws instead of their physical shapes and hidden properties, so I am also committed to using mathematics to explore related philosophical issues in this book. The ancients studied mechanics from two aspects, on the one hand, it was rational and accurate to demonstrate, on the other hand, it was practical. All processes belong to practical mechanics, and the name of mechanics is this truth. "

"Geometry is based on the practice of mechanics. It is nothing more than a part of general mechanics, which can accurately put forward and demonstrate the measurement method. However, because craft is mainly used for the movement of objects, it is generally believed that geometry involves the size of objects, while mechanics involves their movement. In this sense, reasoning mechanics is a science that can accurately put forward and demonstrate the movement caused by any force and the force needed to produce any movement. "

Kirchhoff

1874, Kirchhoff defined mechanics in the first paragraph of Mechanics Lectures: "As for sports science in the research process, we say that its task is to describe the movement in nature in a complete and hypothetical way."

Peiyuan Zhou

Professor Zhou Peiyuan, a famous mechanic in China, said: "Mechanics is a science about the macroscopic motion of matter.

Huygens (christiaan huygens 1629- 1695)

Huygens said: Science should be "I hope to be able to deduce many other phenomena in nature from mechanical principles in the same way". "In real philosophy, the causes of all natural phenomena should be considered in mechanistic terms. In my opinion, we must do this. "

Helmholtz (Herman Helmholtz 182 1- 1894)

Helmholtz said: "The ultimate goal of all natural sciences is summarized in this way, so the task of science is over."

Lord Kelvin (William Thomson 1824- 1907)

Kelvin, a British scientist at the end of 19, said: "My goal is to prove how to build a mechanical model, which will meet the required conditions in any physical phenomenon we are thinking about. I will never be satisfied until I build a mechanical model for a thing. If I can successfully build a model, I can understand it, otherwise I can't understand it. "

Marx (Karl Marx 18 18- 1883)

Mechanics is the "real scientific basis of big industry" surplus value theory (Volume II). Complete works of Marx and Engels, 26 volumes; 1 16

Friedrich engels (1820- 1895)

Understanding mechanical motion is the primary task of science, Dialectics of Nature, People's Publishing House, 197 1: 230.

Laue (Max von Laue, 1879- 1960)

German physicist Laue said: "What is the scientific achievement of mechanics? That's countless! It provides a theoretical basis for any kind of technical design, as long as the design is mechanical, thus deeply involved in daily life; He has also been applied to biological sciences, such as body movement mechanics or auditory mechanics. ....., mechanics describes the motion of particles as large as stars and as small as ultramicroscopic particles, which is consistent with all experiences; In fact, it even partially proves our experiments on molecules, atoms and even smaller elementary particles (electrons, etc.). Therefore, it became the basis of the theory of gas movement and physical statistics founded by Boltzmann-Gibbs. And all these are combined into a beautiful temple, and the architectural system is majestic and touching. Therefore, it is not surprising that for a long time, people equated mechanics with the whole physics and regarded the purpose of physics as attributing all processes to mechanics. Even after people realized that electrodynamics could not be attributed to mechanics around 1900, many people mistakenly thought that mechanics was something like mathematics, something beyond experience. Therefore, when the quantum theory series started from 1900, people gradually realized the effective boundary of mechanics, and how deeply people were shocked! However, even where quantum theory replaces mechanics, the two laws of mechanics remain unchanged: the law of conservation of energy and the law of conservation of impulse. "

Albert Einstein (1879- 1955)

Einstein's passage in "Physics and Reality": "Although we do know today that classical mechanics cannot be used as the basis for ruling all physics, it still occupies the center of all our thoughts in physics. The reason is that no matter how much progress has been made since Newton's time, we still have not reached a new physical foundation, which can make us believe that all phenomena we have studied and all successful local theoretical relationships can be logically deduced from it. "

2. Important figures in the history of mechanics

Galileo (1564- 1642)

Steven (simon stevin, 1548- 1620)

Nicholas? Nicholas Copernicus (1473- 1543)

Archimedes (287 BC-265438 BC)

Newton (isaac newton, 1642- 1727)

Leibniz (Gottfried Wilhelm Leibniz, 1646

Huygens (christiaan huygens, 1629- 1695)

Johannes kepler (157 1- 1630)

Naville (Naville, 1785- 1836)

Laplace (Pierre-Simon Laplace, 1749- 1827)

Lagrange (Joseph Louis Lagrange, 1736- 18 13)

Euler (Leon Hadeuler, 1707- 1783)

Albert Einstein (1879- 1955)

Kovalev Skaya (1850- 189 1)

Saint Venan Island (1797- 1886)

Cauchy, Augustine Louis, 1789- 1857)

All walks of life are engaged in machinery.

Mechanics and astronomy

Earth motion, planetary explosion, three-body and space exploration.

Mechanics and mathematics

Research on velocity acceleration and variable process, limit and calculus, introduction of high-dimensional space, variational method and steepest deviation, energy and functional, conservation law and invariants, dynamic system and differential equation.

Mechanics and physics

Understand the electromagnetic field, the bending of light in the gravitational field

Mechanics, medicine and biology

blood pump

Mechanics and chemistry

From 195 1, Boris Belousov, a Soviet scholar, and anatole Zabo Tynsky, a student, noticed that adding a mixture of bromate and cerium ions to sulfuric acid would produce a colorless and yellowish periodic change. From then on, the study of reaction diffusion wave began.

Because the basic theory of mechanics has matured in many aspects, and there are only a few theoretical problems such as turbulence and strength, the research team of applied mechanics accounts for a large proportion compared with applied mechanics, which is in sharp contrast with the second stage. At that time, the proportion of theoretical mechanics in the research team of the whole mechanics discipline was too much compared with today.

4. Development of aerospace technology in China.

China Hangtian Road

Launch vehicle:

1958, the construction of the first launch site in China began. 1964, China's first biological rocket carrying mice was launched in Anhui, reaching an altitude of 70km.

1 On April 24th, 970, the Long March 1 carrier rocket was successfully launched for the first time, putting China's first artificial satellite, Dongfanghong1,into a predetermined orbit.

The Long March II was developed on the basis of the long-range missile Dongfeng 5. 1975 successfully put China's first recoverable remote sensing satellite into orbit.

Cz-3 was developed on the basis of the Long March II rocket. The roof of the world adopts low-temperature and high-energy liquid hydrogen and liquid oxygen engines. 1On April 8th, 984, the Dongfanghong-2 communication satellite was successfully put into geosynchronous orbit, and China became one of the few countries in the world to launch geosynchronous satellites.

Long March 4 is a three-stage large launch vehicle, which uses conventional liquid propellant. 1 On September 7th, 988, Fengyun/KLOC-0, the first generation meteorological satellite in China, was successfully put into orbit with Long March 4.

1 On February 8, 1994, the Long March 3A, the carrier rocket with the highest high orbit capability in China, successfully made its first flight, sending the Shi Jian No.4 scientific exploration satellite and Kuafu1simulation star into geosynchronous transfer orbit.

Marked by the launch of the Beidou-1 navigation test satellite in 2003, the Long March series of launch vehicles have been launched for the 70th time, with a success rate of 90%, and the overall technical performance has reached the international first-class level.

Satellite:

1 On April 24th, 970, the Dongfanghong 1 satellite was launched by the Long March1carrier rocket. The satellite entered low-earth orbit with an inclination of 68.40 and an operation period of 1 14 minutes.

Since 1975 1 1, China has launched two generations of recoverable remote sensing satellites *** 17, all of which have been successfully recovered except one, and great achievements have been made in remote sensing and microgravity research.

China's first practical communication satellite was officially named Dongfanghong II.

1 On September 7th, 988, China's first meteorological satellite Fengyun1was launched by the Long March 4th.

1999 10 The "Resource One" satellite jointly developed by China and Brazil was successfully launched, and the received satellite image data are widely used in agriculture, forestry, water conservancy, minerals, energy, surveying and mapping, environmental protection and many other parts.

In order to establish the Beidou navigation system in China, the designer successfully developed the Beidou navigation test satellite 1, and successfully launched it for the first time in June 65438+1October 65438+February 2000.

On May/KOOC-0/5, 2002, Haiyang/KOOC-0/and/KOOC-0/Fengyun/KOOC-0/satellite were put into orbit by Long March 4B. Haiyang 1 is the first small satellite in China to move from experimental stage to practical application. Mainly explore the ocean from the sky and promote the development and utilization of marine resources.

By the first half of 2003, China had developed and launched 5/kloc-0 satellites of various types.

Building an Eco-Space City on the Gobi Desert

1958 The space memorial tower of Jiuquan Satellite Launch Center, which started construction, is located in the depths of the Gobi Desert. It is the first satellite launch site in China and the largest space launch center in China.

The arrival of manned space flight: a preliminary discussion

197 1 In April, more than 400 space experts from more than 80 units came to Beijing Jingxi Hotel to discuss manned space flight in depth.

The discussion went smoothly, and the "7 14 Project" for manned space development was determined. China's scientists and technicians seem to see the dawn of manned space flight.

The arrival of manned space flight: the dawn is coming

1992, the government of China officially approved the manned spaceflight project and named it "92 1 project".

1October 20th 1999, 165438+ Shenzhou-1 spacecraft launched into orbit,1October 20th1returned to the ground, and the experiment was a complete success. After the comprehensive experiments and tests of Shenzhou II, Shenzhou III and Shenzhou IV, it was completed in 2003. 30806.8886868866 16

Chang 'e-1 satellite launches lunar orbit exploration mission (2007.338+0438+0).

Seven gods ask heaven (September 25, 2008)

5. The application of mechanics in civil engineering-general situation of structural engineering

A sign of human civilization is reflected in various structures, and objects that can withstand and have certain functions can be attributed to structures, such as tall buildings, cars, ships, planes, bridges, dams, machine tools, telescopes, precision instruments and so on. Broadly speaking, the crust, bedrock and soil layer can also be regarded as structures. The more human progress, the more complex the structure.

The so-called building must be safe and economical;

Second, it should be practical, comfortable and beautiful.

The former problem is to be solved in engineering structure and structural mechanics. The second task belongs to the problem to be solved by the architecture.

Structural design includes strength, stiffness, dynamics and stability analysis of the structure itself.

At present, most of the workload of structural design begins to be borne by computers, which are computational structural mechanics and structural CAD.

Another aspect of structural design is to determine the load on the structure.

It also includes the optimization design of maintaining certain functions, the research of new structural forms and the research of structural processing and molding. If we can choose the optimization method in rigid structure design, we can save 1% steel, which is equivalent to building a steel plant with an annual output of one million tons.

The era when stone, wood and brick are the main building materials.

Whether in the east or the west, before steel and concrete were used as the main building materials, stones, wood and bricks were used for the longest time.

The wood structure is not fire-resistant, so the ancient buildings in China have a long history.

The gate of the Acropolis in ancient Greece

Athenian goddess

Wutai shan xian tong si Wu grain shop

Sagata, Fogong Temple, Yingxian County

Zhao Zhouqiao, Zhao County, Hebei Province

Arch bridge in ancient Rome

6. Early research of material mechanics

Leonardo da vinci studied and discussed the load that a house can bear in his manuscript.

Galileo mentioned in Dialogue between Two New Courses (1638) that the bearing capacity of fixed cantilever beam was investigated.

Edm Edme Mariotte did Galileo's experiments, because their surface equilibrium conditions were all wrong and the coefficients of the results were all wrong.

Jacoby? Bernoulli's research on beams is what people call Bernoulli's beam theory today.

A brief history of concrete:

1774, British engineer Smith Dunzai built the foundation of offshore lighthouse with a mixture of lime, clay and sand, and the effect was very good.

1824, asp Ding, a British stonemason, obtained a patent for burning cement, which is called Portland cement because it is very close to Portland stone.

France set up cement plants in 1840 and Germany in 1855.

In 1970, everyone in the world used 156 kg of cement every year.

Conditions for steel bars and concrete to work together

The physical and mechanical properties of steel bars and concrete are quite different, but they can work together because:

1) There is a good bond between reinforcement and concrete. Under the load, it can ensure the harmonious deformation of the two materials, and the stress is the same;

2) The linear expansion coefficients of steel bar and concrete are basically the same (1.2x 10-5 for steel bar and (1.0 ~1.5) x10-5 for concrete), so when the temperature changes, the two materials.

Advantages of concrete structure:

Reasonable utilization of 1) materials: the material strength of steel bars and concrete can be fully exerted, the ratio of structural bearing capacity to stiffness is appropriate, there is basically no local stability problem, and the unit stress price is low. For general engineering structures, economic indicators are better than steel structures.

2) Good formability: concrete can be poured into various properties and sizes according to requirements, and is suitable for various structures with complex shapes, such as space thin shells and box structures.

3) Good durability and fire resistance, low maintenance cost: the steel bar has a concrete protective layer, which is not easy to rust, and the strength of concrete increases with time; Concrete is a poor heat conductor, and the 30mm thick concrete protective layer can resist fire for 2 hours, so that the steel bar will not lose strength due to excessive temperature rise.

4) The cast-in-place concrete structure has good integrity, and good ductility can be obtained through proper reinforcement, which is suitable for earthquake-resistant and violence-resistant structures; At the same time, it has good anti-vibration and anti-radiation properties and is suitable for protective structures.

5) High stiffness and damping are beneficial to the deformation control of the structure.

6) Easy to use local materials: A large amount of sand and gravel used in concrete is easy to use local materials. In recent years, industrial waste has been used to make artificial aggregate or as an additional component of cement to improve the performance of concrete.

Disadvantages of concrete structure:

(1) self-weight: not applicable to long-span and high-rise structures;

(2) Poor crack resistance: ordinary reinforced concrete structures often work with cracks in the normal use stage, which will affect the durability in harsh environment (open air, coastal and chemical erosion); It also limits the application of ordinary reinforced concrete in long-span structures, and high-strength steel bars cannot be applied;

(3) Limited bearing capacity: in the heavy-load structure and the bottom structure of high-rise buildings, the component size is too large, which reduces the use space;

(4) The construction is complicated, with many processes (shuttering, steel binding, pouring and curing), long construction period and great influence by seasons and weather;

(5) Once the concrete mechanism is damaged, it is difficult to repair, reinforce and reinforce it.

Steel material

/kloc-After the middle of the 0/9th century, steelmaking technology was popularized, and steel was widely used. The first steel ship was built in England in 1859.

1873, Albert suspension bridge across the Thames was built in London, England, with a maximum span of 384 feet.

grid structure

It is a plane or space truss composed of a large number of short steel pipes or alloy pipes that are the same as each other.

It is different from truss, and the members of truss are also different from master and slave.

Because there are many unknowns in analyzing its stress, it developed late and was not widely used until the 1960s.

Buildings are classified by structure:

1. mixed structure

2. Single-storey factory building structure

3. Frame structure: 25-60m.

4. Frame-shear wall structure: 50 50-130m.

5. Shear wall structure: 60-140m.

6. Simplified structure: 70-300m.

7. Long-span structure: > 300m

suspended-cable structure

The earliest suspension bridge appeared in Britain in the 1970s.

Fixing high-strength steel wire on the external concrete ring beam just gives full play to the advantages of steel wire tension and concrete compression.

After the 1960s, large-span exhibition halls and sports fields appeared from time to time.

Power plant cooling tower

Boeing 767

Vancouver's inflatable structure exhibition hall

membrane structure

With the development of chemical industry, nylon membrane and man-made fiber have been widely used. Inflatable structuralists developed it on the suspended cable structure.

Easy to install, inflate, disassemble and carry.

Can be completed in a large span.

It first appeared in the 1940s, and a large number appeared in the 1970s.

aseismatic structure

Many areas in the world are earthquake-prone areas, such as Japanese, Taiwan Province and San Francisco.

When building in earthquake-prone areas, the seismic performance of structures must be considered.

Generally speaking, lightweight flexible structures are beneficial to earthquake resistance.

In addition, the relevant state departments have also formulated the seismic code for building structures.

Sling profile, Humen Bridge in Guangdong, Qingma Bridge in Hong Kong, shock absorber at the root of tie rod of cable-stayed bridge, cable-stayed bridge construction.

thin shell structure

The elastic thin shell theory was developed on the basis of Kirchhoff plate theory of Yuefu at the end of 19.

In the 1920s, Germany used cylindrical shells for roof structures for the first time. Later, shell structure and folded plate structure with spherical surface and saddle surface appeared.

The application of thin shell structure in large cooling towers can be traced back to about 19 13.

Thin shell theory matured in the 1940s, and then thin shells were widely used in the field of architecture. For ships, the aviation structure is earlier.

Ice blocking the bridge hole causes bridge damage.

Rebuild bridge map

Loads acting on structures: seismic load maps

Global earthquake occurrence distribution map

Load acting on the structure

The national load code clearly stipulates wind load, snow load, temperature load, earthquake load, dead load and live load.

In actual design, the design should be determined according to different combinations of some loads.

7. The Development of Mechanics in the 20th Century

Progress of several important problems in mechanics in the 20th century.

1.Review on the development characteristics of mechanics before the 20th century.

? The close relationship between mechanics and mathematics

? New models are constantly appearing in mechanical systems.

? The relationship between theoretical mechanics and applied mechanics

? The role of experiment in mechanics

2. Bifurcation in mechanics.

? Periodic solutions and nonlinear vibration problems

? Disagreement problem

? Differences in hopf

? KAM theorem and further development of stability theory

? Strange attractors and global bifurcation problems

? Nonlinear science

3. Solitary waves, bifurcation and turbulence in fluid.

? Early experimental study of turbulence

? Stability of fluid flow

? Study on solitary waves

? Early theory of turbulence research

? Turbulence and bifurcation

4. Development of continuum mechanics, structural analysis and solid mechanics.

? Development of continuum mechanics

? Development of structural mechanics

? plastic mechanics

? Strength theory and fatigue strength of materials

? Formation and development of fracture mechanics

5. The formation and development of computational mechanics.

6. The development of mechanics education

2 1 the development trend of mechanics in the century

2 1 the development trend of mechanics in the century

1. Combination of macro and micro

2. Intersection and integration of disciplines

3. The combination of mechanics and engineering technology

4. Pay more attention to high-performance computing and advanced experimental technology.

(A) the development trend of solid mechanics

Important scientific issues and frontier fields.

Micro-nano technology

Multi-scale mechanics and cross-scale correlation and calculation

Multi-field coupling mechanics of new materials and structures

Biomechanics of biomaterials and bionic materials

Scientific and engineering computing and software

Development of experimental mechanics instruments, new technologies and new characterization methods

2. The direction of national demand

Strength and failure mechanics of solids

Computational mechanics software

Application of solid mechanics in national security and aerospace engineering

Mechanical problems of large engineering structures and industrial equipment

Explosion and impact mechanics

Environment and disaster mechanics

(B) the development trend of fluid mechanics

1) interfacial fluid mechanics

2) Viscous fingering of configuration growth prototype

3) Blood flow in arteriovenous system

4) Instability of shear flow

5) Turbulence

6) Environmental convection

7) Magnetohydrodynamics

8) Solidification of fluid

9) Geological fluid mechanics

10) ocean dynamics

1 1) global atmospheric circulation

12) vortex dynamics

13) high-speed fluid mechanics

14) hypersonic aerodynamics

15) rarefied gas dynamics

16) multiphase fluid mechanics

17) non-newtonian fluid mechanics

18) computational fluid dynamics

(3) the development trend of general mechanics and basic (dynamics and control) disciplines.

Main research areas:

1) nonlinear mechanics

2) Multi-body system dynamics

3) Analytical mechanics

research direction

6) Nonlinear vibration and control of main equipment under extreme conditions.

7) Nonlinear dynamics of complex network systems

8) micro/nano scale system dynamics and control

9) Some problems of analytical mechanics (such as nonlinear dynamics of constrained systems, etc.). )

10) Dynamics and Control of Elastomer-Rigid Body Coupling System

(D) the development trend of interdisciplinary mechanics

1. Physical mechanics

2. biomechanics

3. Environmental mechanics

4. Explosive mechanics

5. Plasma mechanics

6. Geodynamics

8. Summary

1 mechanics is the earliest precise science;

Mechanics is the most basic discipline in all natural sciences, and mastering mechanics is the gateway to other disciplines;

The methodology formed in the history of mechanics has far-reaching influence on various disciplines;

Mechanics is the theoretical basis of modern engineering technology;

Mechanics is the unity of truth, goodness and beauty.