规范抗震概念设计要点（Key points of seismic concept design for new codes）

1、.新规范抗震概念设计要点（Key points of seismic concept design for new codes）Key points of seismic concept design for new codes1 background materialsSince 70s, people have summed up the experience of large earthquake disaster, and found that the concept design is very important for seismic design of structures&q

2、uot;More important than "computational design". Code for seismic design of buildings beginning in January 1990, GBJ1 1-89 (below)For short, 89 earthquake codes listed in the engineering design must comply with the provisions, to ensure that "concept design" in the actual projectR

3、ealization in. Conceptual design plays an important role in improving the seismic capacity of structures in practical engineering design.Conceptual design is based on the concept of engineering, from the concept of improving the seismic resistance of structures, and conforming to the objective rules

4、 of EngineeringThe method of law and essence, macroscopic control of the object to be designed. Since 1990, structural engineers have put conceptual design in placeGood results have been achieved in practical engineering. At the same time, with the development of the construction industry, the shape

5、 and function of the buildings change with each passing dayChanges and requirements, we found that the content of the conceptual design specified in the 89 seismic codes is not comprehensive enough. January 2002 implementationCode for seismic design of buildings GB50 011 - 2001 "(hereinafter re

6、ferred to as the new seismic code) to the conceptual design requirements provides more comprehensive and more practical, especially the increase of" conceptual design "irregular structures, makes the conceptual design in the industryThe application in the process is more specific and more

7、explicit, and the seismic capacity of the structure is effectively improved. "Conceptual design" is becoming more and more popularIt is of great importance to the engineering circles both at home and abroad.2 conceptual design of the main contentIn order to ensure that the structure has su

8、fficient seismic reliability, the following considerations are mainly taken into account in the conceptual design of construction engineering structuresThe stability of the site and the site soil; the arrangement of the flat and vertical of the building and its overall size; and the selection of the

9、 seismic structure systemThe arrangement of the anti lateral force component and the distribution of the structural quality; the relation between the nonstructural component and the main structure and the anchor between them; the material and construction quality, etc.Below, according to the essence

10、 of the new seismic code, summed up the following points1., the choice of seismic sites conducive to building, it is necessary to avoid building seismic unfavorable areas, should not be built in dangerous areasA, B, C buildings. For unfavorable areas, the structural engineer shall propose to avoid t

11、he requirements and, when unavoidable, shall takeThis method takes into account the indirect cause of structural damage caused by earthquake due to site conditions, such as uneven settlement of foundation soil,The earthquake induced ground fault and crack.2. the layout of the building shall be in ac

12、cordance with the requirements of the conceptual design and shall not be subjected to serious and irregular schemes. IrregularIn building design, horizontal seismic action calculation and internal force adjustment should be carried out, and effective seismic response should be taken to the weak part

13、sConstruction measures. Drawing on international practice and referring to foreign standards, our design is more perfect and reasonable.3. the selection of structural materials and the determination of the structural system should be in line with the requirements of seismic structures. What kind of

14、structural material is used?What kind of structure system is determined by comparison of technical and economic conditions. At the same time, the ductility of the structure and the ratio of strength to gravity are soughtLarge, homogeneous and orthogonal, reduce the center of gravity as much as possi

15、ble, give full play to the strength of the material, and put forward the structure of twoSimilar seismic concept of dynamic characteristics (cycle and vibration mode) in spindle direction.4., set up multi-channel seismic defense line as far as possible. Earthquakes have a certain duration, and may a

16、ct repeatedly, depending onThe analysis of collapsed buildings after the earthquake, we know that the reciprocating action of the earthquake caused serious damage to the structure, and finally collapsedIt is the ability of the structure to bear the gravity load because of the destruction. Properly h

17、andle the relationship between components, so as to form a multi channel defenseLine is an important measure to increase the seismic capacity of structures. For example, a single frame structure, the frame becomes the only anti lateral structureThen the "strong column and weak beam" type d

18、uctility frame is adopted under horizontal earthquake action,The yield of the beam precedes the yield of the column, so that the deformation of the beam can be used to dissipate seismic energy and the frame column is relegated to the position of the second line of defence.5., a reasonable distributi

19、on of stiffness and bearing capacity, and the matching ductility. Increasing the lateral stiffness of structures tends to be more difficultAt the cost of raising the project cost and reducing the ductility index of the structure. Buildings must be strong in the event of a severe earthquakeThe abilit

20、y to collapse, ideally, makes all bars of all members and members of the structure more ductileAnd it's hard to do it in real engineering. It is more economical to selectively increase the ductility of key structures and key rods in structuresEffective method. For example, the upper and lower ri

21、gid frame supported wall structures should focus on improving the ductility of the members below the transfer floor. For framesThe ductility of columns should be improved in frame and frame structures. In engineering design, another way to improve structural ductility is structural loadingUnder the

22、premise of no obvious reduction of the force, the failure shape of the control member is reduced and the axial compression ratio of the compression member is reduced (at the same time, appropriate attention should also be paid to itReduce the shear pressure ratio and increase the ductility of the co

23、lumn.6. ensure the integrity of the structure. The connections between the components must be reliable and meet the following requirements: 1) the bearing of the component nodesThe load-carrying capacity should not be less than the bearing capacity of the connection member. When the yield and stiffn

24、ess of the member are degraded, the bearing capacity and stiffness of the joint remain unchanged.2) the anchorage capacity of the buried parts should not be less than the bearing capacity of the connections. 3) the assembly shall ensure the integrity of the structureThe anti - lateral force componen

25、ts must have reliable measures to ensure space synergy. 4) the structure should be continuous and attention should be paid to the applicationThe quality of the work is avoided, and the continuity of the structure is weakened or even destroyed.3 specification and designThe new seismic code has specif

26、ied specific problems in the design. 1. complex buildings are not always promotedSeismic joint. 2. quantitative division of regular structure and irregular structure. And the construction of architects with mandatory provisionsThe design of the building is limited. As specified in articles 3.4. and

27、1, "architectural design shall meet the requirements of seismic concept design," he saidA serious and irregular scheme should be adopted". 3. the stress resisting member of the given stress concrete shall be provided with sufficient non - stress steel bars.4. non structural components

28、 and their structural connections should be seismic design, such as curtain wall, auxiliary machinery, electrical equipment systemBearings and connections shall be in accordance with the requirements for the use of the earthquake. 5., investors are willing to increase investment to improve security

29、requirementsSeismic buildings are designed with seismic isolation and energy dissipation. 6., the choice of structural materials should reduce the brittleness of materials, priority miningReinforced concrete with a range of specified strength grades with ductility, toughness and weldability.Through

30、the implementation of the new seismic code in the provisions of the seismic concept design to ensure the completion of; by following the concept of seismic design;The principle of making the building has a reliable seismic performance. Conceptual design determines the seismic performance of building

31、s, if conceptual designNot suitable for earthquake resistance, then no matter how many "precision" calculation is useless. Of course, on the basis of doing well in conceptual designTo do the quantitative analysis carefully calculated. The function of new seismic code and the selection of v

32、arious parameters in seismic calculation of each component are madeDetailed requirements are made and the requirements for setting up earthquake response observation systems in buildings are indicated, which indicates the construction work in ChinaDevelopment and progress of seismic science.4 Summar

33、yReinforced concrete structure is a common form of structure. At present, large and medium-sized buildings are being built and proposed in the cityAll of them are reinforced concrete structures. Earthquake is a natural phenomenon. In order to prevent it from causing great disaster to mankind, struct

34、ural engineering is requiredAccording to the new seismic code, the designer applies seismic concept design well. To achieve: 1., structure, function and external conditions are consistent; 2., full developmentAdvanced design concepts; 3., to play the function of structure and achieve coordination wi

35、th the economy; 4., to better solve the structural processing;FiveSeismic analysis by quantitative calculation; 6. concept to judge the rationality of the calculation.Objective things are varied, and they are constantly changing, so they have different opinions about different objective thingsRead, along with the continuous development of things, the concept is constantly evolving, and do