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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 structuresMor
2、e 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 projectRealization in. Conceptual desig
3、n 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 of EngineeringThe method of la
4、w 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 and function of the buildings
5、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 referred to as the new seismic code) to
6、 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 explicit, and the seismic capacity of the structu
7、re 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 sufficient seismic reliability, the following considerations ar
8、e 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 seismic structure systemThe arrangement of the anti lateral
9、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 of the new seismic code, summed up the following points1., t
10、he 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 the requirements and, when unavoidable, shall takeThis method
11、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 accordance with the requirements of the conceptual design and s
12、hall 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 partsConstruction measures. Drawing on international practice and
13、 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 structural material is used?What kind of structure system is
14、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 possible, give full play to the strength of the material, and put
15、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 act repeatedly, depending onThe analysis of collapsed building
16、s 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 handle the relationship between components, so as to form a mu
17、lti 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 ductility frame is adopted under horizontal earthquake action,The yield of
18、 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 distribution of stiffness and bearing capacity, and the matching ductility. Increas
19、ing 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 ability to collapse, ideally, makes all bars of all members and members of the
20、structure more ductileAnd its 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 rigid frame supported wall structures should focus on improving the ductility of
21、 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 premise of no obvious reduction of the force, the failure shape of the control
22、 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 column.6. ensure the integrity of the structure. The connections between the com
23、ponents 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 stiffness of the member are degraded, the bearing capacity and stiffness of the join
24、t 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 components must have reliable measures to ensure space synergy. 4) the structure shoul
25、d 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 specified specific problems in the design. 1. complex buildings are not always promo
26、tedSeismic 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 1, architectural design shall meet the requirements of seismic concept design,
27、 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 and their structural connections should be seismic design, such as curtain wall, auxiliary mach
28、inery, 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 requirementsSeismic buildings are designed with seismic isolation and energy dissipation. 6., th
29、e 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 the implementation of the new seismic code in the provisions of the seismic concept design to en
30、sure 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 buildings, if conceptual designNot suitable for earthquake resistance, then no matter how many precision
31、 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 various parameters in seismic calculation of each component are madeDetailed requirements are made and the re
32、quirements for setting up earthquake response observation systems in buildings are indicated, which indicates the construction work in ChinaDevelopment and progress of seismic science.4 SummaryReinforced concrete structure is a common form of structure. At present, large and medium-sized buildings a
33、re 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, structural engineering is requiredAccording to the new seismic code, the designer applies seismic concept design w
34、ell. 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 with the economy; 4., to better solve the structural processing;FiveSeismic analysis by quantitative calculati
35、on; 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 a good job of re
36、inforced concrete seismic concept designThe plan has profound significance.The six ratios needed to control the design of tall buildings recommendationsThe six ratios needed to control the design of tall buildings1, axial compression ratio: mainly for the control of structural ductility, the specifi
37、cation of the wall, limb and column have corresponding limit requirements, see the anti gauge 6.3.7 and 6.4.6.2, shear weight ratio: mainly for the control of the floor minimum seismic shear, to ensure structural safety, see the anti gauge 5.2.5.3, stiffness ratio: the main structure is to control v
38、ertical rules, so as to avoid vertical stiffness mutation, forming a weak layer, see anti gauge 3.4.2.4, displacement ratio: mainly for the control of structural plane regularity, so as to avoid the formation of torsion, the structure of adverse effects. See gauge 3.4.2.5, cycle ratio: mainly to control the torsion effect of the structure, reduce the adverse effects of torsion on the structure, see the high gauge6, the weight ratio: mainly to control the stability of the structure, so as to avoid structural slippage and overturning, see the high gauge