高层建筑方案设计中结构体系的确定(共13页).doc

精选优质文档-倾情为你奉上高层建筑方案设计中结构体系的确定Determination of structural system in scheme design of high-rise building.TxtThis paper contributes 101 from the little rain forestPdf documents may experience poor browsing on the WAP side. It is recommended that you first select TXT, or download the source file to the local view.Design and engineering practice of high rise buildingDetermination of structural system in scheme design of high rise buildingShi Jianguang Hua Linlin(School of architecture and civil engineering, Xiamen University, Fujian, Xiamen )1 the method of determining the structural system of high-rise buildingFor the whole construction project, the design phase is the construction of key projects in the whole process of investment control, the possibility of Figure 1 visible save construction cost in the design stage and design stage and decreased rapidly from 100% to the beginning of construction has dropped to about 10%. Therefore, the key of 2 control construction cost lies in the stage of design preparation or project design.1Figure 1 the impact of the various stages of the design on the project investment. Data source: Xu Xiaofang: "the cost control of the real estate development should start from the planning and design stage", the contemporary construction, 1999.For high-rise buildings, according to the height of the structure, the choice of reasonable structural system and proper design, the plane shape, profile, 3 and total shape of the building are determined by the building in the preliminary design stage. The structural design is always involved after the architect has completed the architectural design plan in general, and proposed the structural scheme for the architectural scheme. In the architectural design stage, the change of the building shape and other factors will result in structural stress changes, especially for high-rise buildings, 4. As in building design, changed by the shape of wind, wind load and the building by force will change accordingly; change the building gravity load distribution characteristics of horizontal seismic action and building by force will cause the change of. If the building designers in graphic design and vertical design, not on the basis of the stress characteristics of the structure principle and relevant basic design technique, often make the structure engineer 5 structure system can effectively choose reasonable, due to structural instability problems. A structure design in architectural design scheme is put forward and backward to seek solutions on the structure, the structure of the division to diminish the role of the architect to seek after the architectural form in the structure of the 6 solution, make the design completely in a subordinate position. At present, there are several methods to determine the structure system of high-rise buildings at home and abroad:1.1 expert discussionAccording to experts previously engaged in the rich design case, considering some important structural design parameters, the intuition selected one or several may be a satisfactory solution scheme, then the experts will further scrutiny of these programs, so as to decide the satisfactory solution that cut. This method is more subjective, and it is difficult to take into account all the factors that affect the structure selection, and it is difficult to organize 7.1.2 primary selection based on specification and listFor example, the seismic design code of our country stipulates the structure type and maximum height of the reinforced concrete house (Table 1), 9 10 11 abroad. Fintel, Schueller, Taranath and others also summarize and summarize the optimum number of layers for each type of structure (Table 2)8OneDesign and engineering practice of high rise buildingTable 1 maximum height applicable for cast-in-place reinforced concrete buildings (unit: m)Structure type, frame frame, seismic wall, seismic wall frame, core tube, middle barrel0180The fortification intensity is and 0Source: Code for seismic design of buildings. China Construction Industry Press, 2001 chronology, maximum height applicable for cast-in-place reinforced concrete (unit: m) 2Structure type, frame structure, frame shear wall structure, shear wall structure, concrete structure, frame tube structure, tube in tube structure, beam tube structure, frame structure, truss structure, steel structure, frame tube structure, truss tube structureLayers 03040, 80100Source: Fintel, Schueller, Taranath: 91011, 1985-1988 years.This method is intuitive, given the structure of maximum height or number, but when there are multiple alternative structure limit requirements meet, did not give the performance of the method of performance index system and evaluation standard and evaluation or assessment, still need designers using subjective judgment to optimize structure. Considering the building height or the number of layers, in fact, the height and the number of layers should control the structure selection at the same time, and ignore the other factors, such as function, site and so on.1.3 comprehensive fuzzy evaluation methodHe Guangqian China Academy of building research and put forward the suitable structural system of high-rise buildings are fuzzy comprehensive assessment method of calculation is divided into three items: 13 (1) according to the total number of buildings and building function, establish the relationship matrix12. have(2) according to the function of the building, the option quantity A; A is the weighted vector of all kinds of buildings, which can be weighed and determined by the designer. When the lack of bias conditions, according to the following: the weighted vector of high-rise apartment A= (1, 1, 0.3, 0.1, 0.2, 0) A= (1, 0.3 high-rise hotel, 1, 0.2, 0.1, 0) of high-rise office building A= (1, 0.2, 0.2, 1, 0.3, 0 A= (1) public buildings, 0.3, 0.2, 0.3, 1, 0.3) building A= (1, 0.3, 0.3, 0.3, 0.3, 1) (3) for fuzzy evaluation vector B = A - RN. Accordingly, the type of the structural system of the selected tall building can be judged. Although this method considers the building of the number and function of other factors, based on a certain calculation, but the weight value is random and subjective factors, but also failed to take into account the influence of structure selection and other venues.RN = s Mu a mu h Mu o Mu P mu? E?T1.4 concept design"Conceptual design" was first proposed by Mr. Lin Tongyan, a famous Chinese American civil engineering expert. It mainly explained how to design the structural system at the design stage by using the whole method. The purpose of conceptual design is: in particular architectural space, environment and geographical stripsTwoUnder the design and engineering practice of high-rise building, the overall concept is taken into account of the overall structure of the structure, and the mechanical characteristics and relations between the structural master system and the basic subsystems are consciously brought into play and utilized. At the stage of architectural design,By using the concept of approximate calculation method, can quickly and effectively to structure conception, comparison and selection, this method has some errors, but the concept is clear and accurate, is simple and quick, can quickly select the optimal solution and to determine the main components of the basic size. At the same time, it is also the construction stage design stage to judge the computer internal force output data reliable 1415. The requirement of conceptual design in the design process throughout the structure and application of the concept, is a qualitative and quantitative analysis instead of, is the main basis for the foundation design of a structure, safety and economy of the building will have a significant impact, this is not a beam or a 16 plate to reduce the amount of reinforcement. Can be compared, so in the design stage to use the concept of design ideas is very necessary and timely. But the conceptual design of the structure is simplified to be an integral component (such as cantilever), calculation of structure is too rough, and the structure of this simplified model is difficult to meet the structural characteristics of all buildings, always belong to a qualitative judgement, with the price the owners of the building design requirements more and more specific, conceptual design shows its limitations and need to design the structure of the primary quantitative program designed to assist in the plan stage.1.5 expert systemIn order to solve the structure design stage of intelligent design, have put forward a variety of expert system (Expert System), based on the knowledge (knowledge-based), based on the examples (case-based), based on the rules (rule-based) and so on, using the genetic algorithm, fuzzy reasoning, neural network and so on, there will be different comprehensive application of technology of computer aided design. Computer aided design is very good use of the previous design examples to solve the problem of structure design by using the knowledge, strategy, experience and relevant rules and regulations and other aspects of the information, but to make the case base complete, requires a lot of work to collect a variety of architectural examples, easy to cause the bottleneck of knowledge, and the general construction scheme and it is difficult to find site conditions and previous instances of perfectly matched with the design and construction; technology progress, improve the design specifications, just refer to past design examples of building structure design, can easily lead to similar structure design, 17 lag, lack of innovation. So although a lot of design software based on expert system has been developed, almost all of them can not be widely used in practical work.1.6 structural optimization designThe general design of the structure is to put forward the design plan first, calculate the load response, adjust the design artificially, improve the efficiency of the structure, and meet the design requirements of various specifications. The shortcoming is that the design is mainly composed of experienced engineers with the method of trial and error adjust gradually completed, can assure enough design optimization, need to design a long time, main consideration of the design meet the requirements of the standards, the lack of strict cost control in the design process. Optimum design of 18 structure is a kind of fast automatic design process based on computer, can get the optimal design scheme to meet all the set constraint conditions, structure optimization design is an important development in the theory of structural design, through effective optimization algorithm, to optimize the design variables, the optimal goal.Structural optimization can achieve reasonable optimization of resource allocation. At the same cost, the performance of the optimized design scheme is better; or under the same performance, the cost of the optimized design scheme is lower. Structural optimization design is a very good method, but because the designers need to have rich experience in the design, but also must have a good foundation of mathematics and mechanics, and rich knowledge of computers, many designers also difficult to master so many skills. Therefore, the structural optimization design is more and more found in some research papers, and can be really operated in practical engineering.1.7 summarySince structural design is not purely inferential, its conceptual design is closely related to architectural design. Therefore, it is necessary to fully consider the possibility and rationality of the structural scheme while carrying out the layout of the flat 19 surface and the determination of the facade shape and the sectional structure. However, the existing structural system determination methods can not solve this problem well. Because of the structural selection, the safety of the structure should be considered, and the structural system can be quantitatively optimized to ensure that both the strength and stiffness of the structure are satisfied. Another idea is the selection of structure ductility design of structure, in the design stage, in addition to selecting the appropriate architecture, but also through the layout structure optimization, improve the ductility of the structure, to ensure that the structure under earthquake, achieve three level seismic design. In determining the building size, number, column after segmentation, using reasonable structure model, combined with site characteristics, the force analysis of the structure, the trial revised several times, roughly the size can be satisfied with the final selection of structure and main components. Therefore, we propose that in the conceptual design stage, from the architectural design to the structural design, through the reasonable calculation, the use of quantitative resultsThreeDesign method of structure and component roughly determine the size of the design and construction of high-rise building practice (Figure 2), from the structure of the division structure by choosing the appropriate model and calculation method, analysis software compiled for overall scheme design stage structure, operation for architects. The architect just selection and structure related input attributes, can be output to meet the requirements of information architecture and the main components, further aided design and guidance of architects; structural engineers can use the output of the layout, structure and component size information, as the basic parameters of the structure construction drawing design stage, and the structure design is no longer in a passive position, to avoid repeated design process and effective control of construction cost.Figure 2 quantitative design of the program2 calculation method of layer element of high-rise building structure systemA layer cell model of 2.1 spatial structure is proposedAs a project design, the attention is paid to the selection of structure, the regularity of the layout of the facade and the need to judge the mechanical properties of the structure as a whole. In order to analyze macroscopically, the structure can be simplified into the assembly between layers, and the structure of complex shape can be obtained by the combination of basic units (shown in Figure 3). The finite element analysis model of reinforced concrete is applied to the spatial structure. At the same time, based on the structure shape combination and the deformation characteristics of high-rise building, the model of layer cell structure is put forward,Finite element analysis is carried out on each layer of the structure as a unit.Figure 3 combinati