On Application of BIM Technology in Building Design Stage

Transcription

1 Abstract On Application of BIM Technology in Building Design Stage Juan Wang Zhengzhou Institute of Technology, Zhengzhou , China Rapid development of modern information technology has intensified Internet globalization. Under such a background, the traditional building industry has, to catch up with the times, promoted wide application of digital and integrated information technologies that are centered on BIM in building design. However, with continuous development of the building industry, BIM technology has failed to demonstrate its advantages when it comes to designing the intersection of integrated system of pipelines laid by different work types and the building, building structure or other elements. In view of the situation, based on researches on BIM-based building design and such features of BIM technology as visuality, collaboration, optimization, simulation and so on, the paper analyzes, through comparison of SATWE and YJK Software, shock resistance of the building structure at the intersection of the building and the pipelines. The analysis results show that BIM technology can help address problems emerging in the whole life cycle of the building; besides, compared with traditional software SATWE, BIM-based YJK Software renders more accurate shock resistance analysis, which also indicates that BIM technology is superior to other technologies when it comes to application in building design. Keywords: BIM, Building Design, Structure, Applied Research. 1. RESEARCH BACKGROUND 1.1 Literature review Thanks to industrialization and development of digital information, the building industry has experienced unprecedented development. Besides, with development of modern technology and economy and acceleration of urbanization, there are more integrated buildings with complex structure and for commercial and/or residential purpose (Ding, 2014). 2D modeling method adopted in traditional building design is no longer applicable. During exploration of building design methods, BIM technology has become a new trend in information management and exchange of building projects, and has thus been widely used in building planning and design. As a new digital 3D modeling method, BIM technology has not only improved the quality of building design drawings, but also enhanced transmission of building design information, which in turn leads to higher information transparency at building design, construction and other stages. In the development history of the world s building industry, BIM technology was first applied and promoted in the early 21 st century. In 2003, the US General Services Administration ( GSA ) proposed the 3D-4D-BIM pilot project to demonstrate the effect of applying BIM technology in the life cycle of buildings (Dossick and Neff, 2009). However, BIM technology wasn t introduced into China s building industry until In 2007, promotion and application of BIM technology in building design was first discussed at the national prospective design industry exchange meeting. In 2008, BIM technology was applied in building projects. Given the situation, Zhang Jianping and other researchers, based on IFC standards, put forward BIM 3D solid modeling based on CAD graphics, which can meet the stage-specific requirements of building projects and in turn enhance reusability of data (Zhang, 2009). Zhou Wenbo and Jiang Jian et al. analyzed the value and application process of using BIM in prefabricated building design, studied how to apply BIM to fabricated housing design, and analyzed applicability of BIM technology to the two building types based on actual projects, which provides a reference for further application of BIM technology to design prefabricated buildings (Zhou and Jiang, 2010). 1.2 Research purpose With improvement in computer hardware & software and building design analysis technologies, BIM technology has also developed by leaps and bounds. Under such a background, architects can deliver high-quality and perfect building information models in a faster and better manner. BIM technology has helped architects turn creative ideas into final design sketches, and thus given rise to leap-forward development of the building data information 743

2 technology. Therefore, the great potential of BIM technology in the building industry has been recognized by numerous architects and project participants. In building design, BIM technology can effectively control the cost, improve safety and quality management, save time, acquire project data, and reduce operation and maintenance costs; moreover, it can help the design institute enhance design efficiency and quality, improve competitiveness, achieve design collaboration among work types, and reduce reworking caused by design errors. BIM technology can simulate the building acoustics, optics and energy consumption, as well as habitants comfort, which is conducive to promoting green buildings. For the construction party, BIM can create more value at the level of work type, the project and the enterprise. Therefore, BIM can be given full play if it is effectively used by each participant and each work type and at every stage (Qin, 2011). 2. BIM-BASED ANALYSIS OF BUILDING SCHEMATIC DESIGN AND ITS FEATURES The concept of BIM was first proposed by Dr. Chuck Eastman, a professor of architecture and computer science at Georgia Tech College, which integrates information on various stages of the building (such as construction, design, operation and maintenance) into the building model. BIM aims to build an information exchange platform that facilitates collaboration and execution, so as to help project participants timely acquire information and freely add information, and in turn improve work efficiency and project quality (Cheung et al., 2012). To be specific, before implementation of the building project, simulation is conducted online with BIM technology to optimize project schematic design. Besides, this can help identify potential problems with the construction process, thus enhancing control over project progress and quality. At present, 3D design has been successfully applied in construction of many large-scale public facilities, which has accelerated digitalization of building design industry. As a result, BIM technology has led to another reform in building design scheme following the reform driven by throwing off the drawing board. Compared with traditional building design method, BIM technology enables building designers to avoid repeated comparison and calculation of building information, but to arrange elements and design building information in virtual 3D space with the help of computer software. Based on existing BIM platform, the paper attempts to establish the BIM process for building design stage, as is shown in Figure 1. The BIM-based 3D scheme not only shows the main structure of the building, but also highlights the environmental art of the building shape, which can facilitate effective communication between the designer and the structural engineer, analysis of the main building structure from many perspectives (i.e. art display, practical use, structural mechanics, etc.), and determination of the best building and structure scheme. Therefore, BIM technology can effectively reduce design changes at the construction stage thanks to visuality of 3D model design, efficient collaborative design by different work types, and high design accuracy. Architectural scheme phase Structural scheme selection Building initial stage Structural calculation and design Construction drawing phase Structural construction drawing Water, heating, electricity and other professional design Figure 1. Building Project Design Process Based on BIM Platform 2.1 High visuality At the building design stage, in most cases, designers will submit the preliminary floor plan to the structural designer. Then, the structural designer will, according to the floor plan, incorporate the structure scheme, sectional dimension, shape and appearance, and other elements into the 3D drawing, so as to evaluate whether layout of structural elements will exert negative impact on the artistic effect and function of the building. Given the situation, the designer can, relying on visuality of BIM technology, directly extract the data for structural analysis from the building model developed by the architect, make modification and calculation accordingly, and arrange structural 744

3 elements inside the contours of the building model. Then, the designer can carry out miscalculation and comparison on the established 3D model, with an aim to establish the structural working drawing for the building. After that, the construction party can, based on the model having been subject to collision detection, further optimize the building model and the construction drawing in the 3D building model. Besides, it can incorporate the water, heating, power and other professional equipment into the 3D model, and arrange layout of the pipelines and equipment per work type. 2.2 Efficient collaborative design Relying on the BIM-based tool design platform, all work types can share the center coordinates through the working set. The architect and the structural designer can, after establishing the preliminary building scheme model, submit the model to the working set, and make final adjustments. Moreover, at the stage of designing the working drawing, the structural designer can, based on the building model, supplement template drawing and detailed structure drawing (including the upturning, lower closure, and local bridging piece of the beam), and warn every dept. involved of changes in the building model through the BIM platform, so that the structural designer can be promptly informed of changes in the building model and make modifications accordingly. Facilities in the building can also be modified accordingly, such as the wire layout, cable trays, water pipes and ducts, etc. In addition, through collision analysis of the facility model and the structural model, the structural designer can finalize the construction effect model of the building. 2.3 Parametric design BIM technology establishes and maintains the building model based on data information, and carries out the final effect design based on BIM tools. In the process, building information data is constantly added to the model. For example, in traditional CAD method, two straight lines can represent a beam. When the beam represented by the two lines has a displacement in structural calculation model, modifications shall be made manually in the CAD drawing. However, manual modification may lead to failure in timely modifying relevant information, thus exerting negative impact on the design scheme. In contrast, BIM technology relies on drive parameters in building design, namely, when a structural element changes, the overall model will vary with it automatically. Moreover, linkage of BIM technical parameters helps achieve fast modifications and adjustments of the building model during the design process. Therefore, the designer of each work type can concentrate on optimizing the building model and detail design, rather than pay close attention to modify the working drawing. 3. BIM-BASED SHOCK RESISTANCE ANALYSIS OF BUILDING STRUCTURE The paper, by taking a building complex with transfer floor structure as an example, describes the BIM-based shock resistance analysis of the building structure. Therefore, PKPM structure model and Revit structure model are established with conventional method and BIM technology respectively. Besides, efforts are made to analyze seismic response of the building structure respectively with SATWE (conventional structural analysis software) and YJK finite element analysis software with BIM structural analysis software interface. According to the Load Code for the Design of Building Structures, the ground roughness is of Grade B, and the corresponding floor live load is shown in Table 1 (the reference snow pressure is 0.65kN/m 2, and the reference wind pressure is 0.30kN/m 2 ). Moreover, the project is of framed shear wall structure. Based on the above information, BIM structure model can be established with such basic elements as structural elements, beams, structural columns, structural plates, etc. Table 1 Basic Load Value Type of building Floor live load (standard value) Kitchen floor 1.8N/m 2 Room and balcony 2.5N/m 2 Superstore and community building 4.0N/m 2 Building for cultural and sports activities 4.8N/m 2 Public washroom and other public facilities 3.5N/m 2 Public corridor and emergency staircase 4.5N/m 2 Roofing accessible by people 2.4N/m 2 Roofing inaccessible by people 0.8N/m 2 Public elevator, machine room, etc. 6.9N/m 2 745

4 Modal analysis method is usually adopted in seismic response analysis of non-coupled linear structures or decoupled linear structures. Therefore, according to the D Alembert s principle, the dynamic balance equation of structural system under seismic action is as follows: F 1 (t) + F D (t) + F S (t) = F(t) (1) where, F 1 (t) refers to the inertial force vector acting on the node mass; F D (t) refers to the viscous damping force vector; F S (t) refers to the internal force vector assumed by the structure; and F(t) refers to the load vector applied to the structure. When F(t) is zero and the structure is undamped, and if all particles are in simple harmonic free vibration at the same frequency ω, and with the same phase angle ωt+φ but different amplitudes X i, then the displacement vector X(t) is: X(t) = {X} sin(ωt + φ) [K] ω 2 [M] = 0 (2) As it is impossible that the amplitude {X} of all nodes is zero in the vibration process, then: [K] ω 2 [M] = 0 (3) Based on the analysis of 18-order mode, the structural model is calculated respectively with SATWE finite element software and YJK Software. Then, the first-6-order mode is read from the calculation results, and the structural natural vibration period of each order mode is shown in Table 2. In building structure design, to ensure that the building structure has excellent anti-twisting property, period ratio (i.e. the first natural vibration period where the structure is mainly twisted versus the first natural vibration period where the structure mainly makes translational motion) is adopted to indirectly show shock resistance and anti-twisting property of the overall building structure. Therefore, period ratio is a macro-index for measuring shock resistance of the building structure. Table 2 Structural Natural Vibration Period and Vibration Mode Characteristics Vibration mode SATWE YJK Period Torsion coefficient Period Torsion coefficient According to Appendix F.2 of the Load Code for the Design of Building Structures, the formula for calculating the basic natural vibration period of reinforced concrete structure is: where, n is the total number of building floors. T t = ( )n (4) After calculation, the basic natural vibration period of the selected building structure is 2.0s-3.5s. It can be seen from Table 2 that the analysis results achieved with SATWE and YJK respectively are both within the range, which means that overall stiffness of the two structural models are suitable. Moreover, according to Table 2, the higher-order modes (4-order and above) have a period shorter than that of the first-3-order modes, so it is inferred that there is low probability to have higher-order modes (above 3-order). This indicates that the building structure has high shock resistance. However, when there is higher-order mode, the damage done by earthquake will be huge. By comparing the vibration periods calculated respectively with SATWE and YJK, it is concluded that, with the same aseismic design parameters and the same floor, the period calculated with YJK is slightly shorter than that calculated with SATWE. Among the others, the deviation of the first 3 periods is about 6.7%, which is acceptable. However, YJK finite element analysis software, which has BIM structural analysis software interface, is more accurate due to such features as high visuality, efficient collaborative design, and parametric design. 746

5 4. CONCLUSION All in all, application of BIM technology has brought great changes to the traditional building industry. BIMbased building design enables designers to design building model in a fast and convenient manner with original information resources, and to make timely adjustments and modifications based on BIM feedbacks. This has effectively addressed various problems with traditional building industry that are arising from weak control over information, such as high cost, low quality, etc. In addition, application of BIM technology to solve space collision problems has provided a reference for collaborative design by different work types in building design stage, and for testing and optimization of 3D models. It is believed that in the near future, BIM technology will experience wider application in other industries other than the building industry. REFERENCES Cheung F.K.T., Rihan J., Tah J. (2012). Early stage multi-level cost estimation for schematic BIM models, Automation in Construction, (05), Dossick C.S., Neff G. (2009). Organizational divisions in BIM enabled commercial construction, Journal of construction engineering and management, 136 (04), Jeong Y.S., Eastman C. (2009). Benchmark tests for BIM data exchanges of precast concrete, Automation in Construction, (04), Jung Y., Joo M. (2011). Building information modelling(bim) framework for practical implementation, Automation in Construction, 20 (2), Linderoth H.C.J. (2010). Understanding adoption and use of BIM as the creation of actor Networks, Automation in construction, 19 (01), Liu S. (2008). Application of building information model technology, Architectural Journal, (2), Qin J. (2011). Application of BIM in architectural design phase, Architectural skill, (Z1), Sanguinetti P. (2012). General system architecture for BIM: An integrated approach for design and analysis, Advanced Engineering Informatics, 26 (2), Zhang J. (2009). 3D geometric modeling and model conversion of BIM based on IFC, Information Technology in Civil Engineering, (9), Zhou W., Jiang J. (2010). Research on Application of BIM technology in prefabricated residential building, Construction technique, 41 (377),