BIM technology for model construction in the architectural design stage?

At this stage, the traditional two-dimensional design can no longer meet the actual needs of the architectural field, and it seems to be difficult to deal with the problems of architectural design. The new design of three-dimensional simulation software was developed based on this background, through the software can build a collaborative design technology platform for all professions, so that the building system to obtain the ideal technical support, so that it is more scientific and efficient in the creation of bim model. It elaborates on the application of modern BIM technology in the structural design of buildings, and systematically explores and analyzes the following three levels: in-depth understanding of BIM theory and technology; introduction of modeling software based on BIM technology; and the use of Revit software to construct a BIM model of the main body of the building with a complex building as the research object.

1, the theoretical knowledge of BIM

BuildingInformationModeling (BIM) uses contemporary three-dimensional digital technology to optimize all the links in the project building, so that the quality of engineering and construction can be improved, and the time-consuming engineering and construction can be shortened. At the same time, this technology covers the data model of all work sectors in the construction system, which is a process of processing and operating engineering data from planning to demolition of a construction project.The advantages of BIM are very obvious, such as it enables operators to carry out more convenient visualization operations, and it can support the concordance simulation, which can make a significant increase in productivity and reduce the project's cost. The quality of work projects is further optimized by reducing the barriers to communication between all parties involved.

Previous CAD designs typically utilized a two-dimensional platform to carry out operations and interact with data through a variety of design drawings. The new BIM technology can support visualization, and it is the same as 3D design, can build virtualized physical image to support staff project analysis and research. For example, the overall wiring inside the construction project, pipeline layout arrangements, etc. can use the visualization function to verify its rationality, so that the limited space in the building to get more full and scientific use, to avoid conflict between professional pipelines, so that the synergy of the various professional departments to significantly improve. At the same time, it can also assist staff in a shorter period of time to find the latent problems in the project matters, so that the project drawings in the various professional departments to submit the error is not likely to occur.

2. Modeling software based on BIM technology

The modeling software makes rational use of contemporary computer technology to create a structural model of the project. At the same time through the same data structure for the integration of the whole system, and then with the help of more scientific and efficient parameterization technology, so that the construction engineers to better information interaction between, in order to promote the creation of the project information model.BIM technology is constantly updating and development, and the field of its application is also constantly expanding. At this stage, in the world have a good reputation for BIM technology software developers a **** there are four, they are: Autodesk's Revit series of software; Bentley company's BentleyArchitecture series; Graphisoft company's ArchiCAD; Nemetschek company's ALLPLAN software. Corporation's ALLPLAN software. The software they have developed is shown in Figure 1, of which, the more representative is Revit software.

2.1 Introduction to Revit Software Revit developed a software called RevitStructure in 1997, which was written and developed by Pro/E. When Revit was first introduced, even though it can exchange data with AutoCAD software and programming, however, the software itself has a certain difference between the program structure and AutoCAD, in general Revit software can be understood as a new technology, which represents a new type of technology pioneering. revit software is a more mature software at that time, which emphasizes the application of BIM technology and can It emphasizes the application of BIM technology and is able to complete the engineering project design life cycle of good convergence and data information transmission.

For the construction industry, Revit is the ideal realization of BIM, which uses relational databases to build more scientific and rational three-dimensional building models, and is able to set up two-dimensional graphics and deal with a lot of non-graphic construction data. Drawing drawings have the basic elements have changed significantly, from the previous point, line and other elements converted to walls, windows beams and other objects, in essence, it is through the modeling language for the entire building structure depicted, it is a class of programs written specifically for the project engineering inspection. The entire application is based on Revit software for BIM. It is able to represent the building, structure and other indicators and graphic structure more perfectly, and can be analyzed and observed in many ways, so that the information and structure of the building presents more accurate data.

2.2 Application of BIM technology in the architectural design of an office building

This paper intends to take a comprehensive office building as the object of study, and use Revit software to complete the modeling of the main body of its building. For the design of the main body of the building, the structural design of the reinforcement ratio, load and other information is not studied for the time being, in order to prepare for the collaborative design of the building and water supply and drainage specialties.

2.2.1 Project Preparation When creating other projects in Revit software, any project will take the project sample as the basis of program design, in the sample file to write different formations, write the relevant information parameters, in addition, the file corresponding to the suffix name should be changed to ".rte", in the Revit software, the core project are all the same. In Revit software, the core project must use the template file. The sample file contains the initial parameters of the project set by the system, including the default unit of measurement, floor height information, the number of floors set information, display settings, line settings and so on. In Revit software, a proper project template can reduce the number of settings and adjustments in the later modeling process and improve the efficiency of project design.

Using the Project Browser, you can switch operations between views and provide powerful, easy-to-use view manipulation tools to zoom, pan, rotate, and other operations on each view. At the same time, the software can also display the attribute list of the operation content in real time, assisting the designer to clarify the attributes of the design content while designing, as shown in Fig. 2 and Fig. 3. In the process of modeling, it is inevitable to edit and modify the graphical elements used in the process, so that they can meet the actual needs of the designer. Therefore, the software also covers a number of editing tools to carry out a series of edits to the elements. These modification and editing tools can be accessed through the Modify tab, as shown in Figure 4.

2.2.2 Establishment of the working set of the building project as a complex design system engineering, generally by a number of professional **** with the participation of the completion of the process, but in the inter-professional collaborative design process can not be simultaneously on the BIM design of multiple professions. Therefore, in the overall project design process, each specialty can be based on the professional design needs to establish multiple working sets.

In this paper, in the collaborative design process between the architectural profession and the water supply and drainage profession, the architectural profession can establish its own working set according to the requirements of the architectural design, and at the same time set up the working set permissions to designate the relevant designers who can view the working set. Similarly, water supply and drainage specialties are usually able to set up a special working set, but also in accordance with the required project to set up a different working set, such as water supply and drainage specialties can be divided into water supply, drainage, hot water, fire protection, water and other sub-systems according to the detailed design, each sub-systems can be set up working set, to facilitate the designers to more accurately manage the design of the contents of the design, as shown in Figure 5.

2.2.3 Creating Elevations and Axis NetsElevations and axis nets are important spatial positioning information in architectural design, and Revit uses elevations and axis nets to locate the relative spatial relationships of the various elements involved in model construction. As a matter of fact, elevation and axial network are the working basis and prerequisite for realizing 3D collaborative design among architectural, structural, and equipment disciplines on the Revit platform. When designing the project in Revit software, the first thing to do is to measure the elevation and axis network, and then set up doors, windows and other building models in accordance with the elevation and axis network related information, which is in line with the design process of the vast majority of domestic architectural design institutes. Before Revit starts modeling, it should make an overall plan for the floor height and elevation information of the project.

When building the model, Revit determines the height information and spatial location of building components within the model through elevation. In addition, the axis network object in Revit is similar to the elevation object, which is a set of "axis network surfaces" perpendicular to the elevation plane. Designers can locate the project elements based on the axis network in the plan view of the project, and finally determine the specific spatial location of the components in the model by combining the elevation information. In the process of drawing elevation and axis network, use the "Elevation" and "Axis Network" commands in the "Common" tab "Datum" panel in Revit. "command, the two-dimensional drawings constructed as a program template, the project elevation and axis network information for drawing, but also pay attention to the marking of the relevant labeling and numbering, as shown in Figure 6, Figure 7.

2.2.4 Load family file family is the foundation of the RevitArchitecture project, regardless of the model elements or annotated elements, are composed of a variety of component families. families in RevitArchitecture have two forms: system families and loadable families. System families are predefined in RevitArchitecture, and the information about the system families is saved in the sample and project, which is used to create the basic elements of the project, such as walls, floors, ceilings, staircases, etc. Loadable families can be loaded by the user. Loadable families can be created by the user or obtained through communication between designers, and then saved independently in the software as ".rfa" format family files. RevitArchitecture does not allow users to create, copy, modify, or delete system families, but it can copy and modify the types of system families so that users can create customized system families according to the specific needs of the project. create customized system family types based on the specific needs of the project.

RevitArchitecture's model category families are categorized into standalone and subject-based families. Stand-alone families are generally program structures that are not based on another body, such as furniture, structural columns, and so on. Body-based families are components that cannot exist independently but must be dependent on a body, for example, doors, windows, and other elements must exist with walls as the body. Body-based families can be dependent on the body of the wall, ceiling, floor, roof, line, face, RevitArchitecture provides a family of sample files based on these body elements. When the family is used in a project, you can adjust all the parameters defined in the family in the "Type Properties" dialog box, or you can use the copy function to create a type of family that is similar to the family. For example, you can use the new family type of the system family of the exterior wall 300mm. 240mm family type, through the copy, modify the parameters of the operation to create the exterior wall, as shown in Figure 8.

3, the construction of the model

This time the main use of Revit on the project's building body and structural walls, beams and columns for the design, the construction of the main body of the building's BIM model, and this BIM model as the basis for the completion of inter-professional collaborative design with the water supply and drainage specialties *** with the construction of a comprehensive architectural, structural, water supply and drainage specialties to build the design information of the BIM model.

3.1 Create the main wall of the project

In Revit software, the wall can be categorized as a system family, which can be converted into a new three-dimensional wall model according to the corresponding wall structure data. The software not only has a wall tool as a way to facilitate model drawing as well as generation of wall objects. When creating a wall in Revit, you need to define the type of wall, including wall thickness, practice, material, function, etc., and then formulate the plan position, height and other parameters of the wall. Using the 2D plan drawing as the design blueprint, the main components of the project such as walls, structural columns and structural beams are laid out. During the design process, import the 2D CAD drawings, adjust the drawings so that they correspond to the axis network, and then draw the walls and structural columns of the project on this basis. The corresponding plan view and three-dimensional view are shown in Figure 9, Figure 10.

After completing the layout of project walls and structural columns, structural beams, structural floor slabs and other structural components are laid out, and these structural components will be involved in pipeline synthesis and collision checking in the process of collaborative design with the water supply and drainage specialties. The role of structural columns is to support the building as a whole. Structural walls and structural beams are also important load-bearing components, although the structural components are not for rebar placement and load analysis and other operations, but in the co-design process with the drainage profession, the structural components must be taken into account. revit provides a series of structural tools to complete the structural walls, columns, beams, and other basic structural components of the creation.

3.2 Adding other components needed for the project

After completing the construction of the main walls of the project, other components needed in the building model are laid out. Components, including doors, windows, stairs, railings, floor and roof, Revit software provides a variety of components of the family file samples, can be loaded directly into the software to use, commonly used components of the properties shown in Table 1. Take the drawing of stairs as an example to introduce the creation of basic components in the model building process. First of all, define the type of staircase, based on the original system family type of the software, copy the type of staircase needed to create the project, and set the function of the staircase, the depth of the tread and the material and other attributes, as shown in Figure 11.

After the attribute settings are completed, the layout and modification of the stairs are completed by combining the drawn reference planes under the plane and 3D view, as shown in Figure 12 and Figure 13. At the same time, the BIM-based 3D design of the building, pay attention to the "what you see is what you get" visualization design, designers can accurately and clearly understand the design effect of the building interior through the three-dimensional view of the BIM model. In order to further optimize the final design of the building, the corresponding rendering function can be used to render the target wall and its components to make it more sensory characteristics, fully reflecting the software's humane design. The project finally used Revit software to build the project's main building BIM model shown in Figure 14.

4, conclusion

This paper is based on the theory of BIM technology and the application of the relevant results of the study, from a macro point of view on the future prospects for the application of BIM technology in the future and the current architectural modeling structure is analyzed. Using three-dimensional simulation software Revit to complete the modeling of the building body of the office building project. The difficulties encountered in the drawing around the modeling are elaborated in detail, while the ability of the software to deal with two-dimensional plane drawings makes further requirements.

More about the engineering/service/procurement category of the tender writing production, to enhance the winning rate, you can click on the bottom of the official website customer service free consultation:/#/?source=bdzd