Construction-specific spatial information reasoning in Building Information Models

In recent years, there have been significant advances in modeling technology for object-oriented building products. However, the building models are still lacking of providing construction-specific spatial information required for construction planning. Consequently, construction planners visually analyze building product models and derive geometric characteristics such as bounded spaces and exterior perimeter to develop detailed construction plans. Such a process presents fragmented information flows, from building product information to construction planning, that rely on subjective decisions of construction planners. In order to overcome these drawbacks, this research proposes a geometric reasoning system that analyzes geometric information in building designs, derives the construction-specific spatial information, and uses the information to assist in construction planning. The scope of presented work includes detecting work packages formed by faces during construction, such as large work faces and bounded spaces, and using information in the work packages directly to support planning of selected indoor construction activities. The main features of the proposed system named Construction Spatial Information Reasoner (CSIR) include a set of relationship acquisition algorithms, building component relationship data structure, and interpretation of the relationship to support detailed construction activity planning. The relationship acquisition algorithms identify adjacency between building components that is stored in the relational data structure. Then, acquired adjacency relationships are transformed into a set of graphs that represent work packages. To implement the proposed approach, CSIR utilized a commercially-available Building Information Modeling (BIM) platform and the algorithms were imbedded to the BIM platform. For validation, CSIR was tested on a real commercial building. For interior ceiling grid installation activities, CSIR successfully detected existing work packages and analyzed the spatial characteristics impacting construction productivity. The major contribution of the presented research would be to enable a realistic analysis of building geometric condition that is not possible in current BIM and a seamless information flow from building product information to construction process plans. These can potentially reduce current manual and error-prone construction planning processes. Limitations and future research suggestions are also presented.     

Semantic enrichment of building and city information models: A ten-year review

Building Information Models (BIMs) and City Information Models (CIMs) have flourished in building and urban studies independently over the past decade. Semantic enrichment is an indispensable process that adds new semantics such as geometric, non-geometric, and topological information into existing BIMs or CIMs to enable multidisciplinary applications in fields such as construction management, geoinformatics, and urban planning. These two paths are now coming to a juncture for integration and juxtaposition. However, a critical review of the semantic enrichment of BIM and CIM is missing in the literature. This research aims to probe into semantic enrichment by comparing its similarities and differences between BIM and CIM over a ten-year time span. The research methods include establishing a uniform conceptual model, and sourcing and analyzing 44 pertinent cases in the literature. The findings plot the terminologies, methods, scopes, and trends for the semantic enrichment approaches in the two domains. With the increasing availability of data sources, algorithms, and computing power, they cross the border to enter each other’s domain. Future research will likely gain new momentums from the demands of value-added applications, development of remote sensing devices, intelligent data processing algorithms, interoperability between BIM and CIM software platforms, and emerging technologies such as big data analytics.     

An investigation into the applicability of building information models in geospatial environment in support of site selection and fire response management processes

Some tasks in the construction industry and urban management field such as site selection and fire response management are usually managed by using a Geographical Information System (GIS), as the tasks in these processes require a high level and amount of integrated geospatial information. Recently, a key element of this integrated geospatial information to emerge is detailed geometrical and semantic information about buildings. In parallel, Building Information Models (BIMs) of today have the capacity for storing and representing such detailed geometrical and semantic information. In this context, the research aimed to investigate the applicability of BIMs in geospatial environment by focusing specifically on these two domains; site selection and fire response management. In the first phase of the research two use case scenarios were developed in order to understand the processes in these domains in a more detailed manner and to establish the scope of a possible software development for transferring information from BIMs into the geospatial environment. In the following phase of the research two data models were developed - a Schema-Level Model View and a geospatial data model. The Schema-Level Model View was used in simplifying the information acquired from the BIM, while the geospatial data model acted as the template for creating physical files and databases in the geospatial environment. Following this, three software components to transfer building information into the geospatial environment were designed, developed, and validated. The first component served for acquiring the building information from the BIM, while the latter two served for transforming the information into the geospatial environment.The overall research demonstrated that it is possible to transfer (high level of geometric and semantic) information acquired from BIMs into the geospatial environment. The results also demonstrated that BIMs provide a sufficient level and amount of (geometric and semantic) information (about the building) for the seamless automation of data management tasks in the site selection and fire response management processes.     

An approach to combine progressively captured point clouds for BIM update

Building information models (BIMs) provide opportunities to serve as an information repository to store and deliver as-built information. Since a building is not always constructed exactly as the design information specifies, there will be discrepancies between a BIM created in the design phase (called as-designed BIM) and the as-built conditions. Point clouds captured by laser scans can be used as a reference to update an as-designed BIM into an as-built BIM (i.e., the BIM that captures the as-built information). Occlusions and construction progress prevent a laser scan performed at a single point in time to capture a complete view of building components. Progressively scanning a building during the construction phase and combining the progressively captured point cloud data together can provide the geometric information missing in the point cloud data captured previously. However, combining all point cloud data will result in large file sizes and might not always guarantee additional building component information. This paper provides the details of an approach developed to help engineers decide on which progressively captured point cloud data to combine in order to get more geometric information and eliminate large file sizes due to redundant point clouds.     

Information Quality Assessment for Facility Management

Assessing the quality of building information models (BIMs) is an important yet challenging task within the construction industry as projects are increasingly being delivered with BIM. This is particularly essential for facility management (FM) users as downstream information consumers that depend on the quality of models developed in the previous project phases. The research presented in this paper addresses this challenge by introducing a framework for information quality assessment (IQA) of BIMs for FM uses. The IQA framework is the outcome of an extensive study of two large owner organizations involving numerous BIM projects. The framework is structured based on the essential FM subjects: assets, spaces, and systems, and the model characteristics: objects, attributes, relationships, and spatial information. The framework is then operationalized through the development and evaluation of information quality (IQ) tests using BIM model checking tools across three projects with different levels of detail and complexity. The proposed IQA framework and associated tests advance the state of knowledge about BIM quality in terms of methods to represent and evaluate conformance to owner requirements.     

Model interoperability in building information modelling

The exchange of design models in the design and construction industry is evolving away from 2-dimensional computer-aided design (CAD) and paper towards semantically-rich 3-dimensional digital models. This approach, known as Building Information Modelling (BIM), is anticipated to become the primary means of information exchange between the various parties involved in construction projects. From a technical perspective, the domain represents an interesting study in model-based interoperability, since the models are large and complex, and the industry is one in which collaboration is a vital part of business. In this paper, we present our experiences with issues of model-based interoperability in exchanging building information models between various tools, and in implementing tools which consume BIM models, particularly using the industry standard IFC data modelling format. We report on the successes and challenges in these endeavours, as the industry endeavours to move further towards fully digitised information exchange.     

Building information modelling - Experts’ views on standardisation and industry deployment

The goal of the single building information model has existed for at least 30 years and various standards have been published leading up to the 10-year development of the industry foundation classes. These have been initiatives from researchers, software developers and standards committees. Now large property owners are becoming aware of the benefits of moving IT tools from specific applications towards more comprehensive solutions. This study addresses the state of building information models and the conditions necessary for them to become more widely used. It is a qualitative study based on information from a number of international experts and has asked a series of questions about the feasibility of BIMs, the conditions necessary for their success, and the role of standards with particular reference to the IFCs.Some key statements were distilled from the diverse answers received and indicate that BIM solutions appear too complex for many and may need to be applied in limited areas initially. Standards are generally supported but not applied rigorously and a range of these are relevant to BIM. Benefits will depend upon the building procurement methods used and there should be special roles within the project team to manage information. Case studies are starting to appear and these could be used for publicity. The IFCs are rather oversold and their complexities should be hidden within simple-to-use software. Inevitably major questions remain and property owners may be the key to answering some of these. A framework for presenting standards, backed up by case studies of successful projects, is the solution proposed to provide better information on where particular BIM standards and solutions should be applied in building projects.     

Graph-based retrieval of building information models for supporting the early design stages

Building information modeling (BIM) principles are transforming today’s communication and working processes in the field of construction, however the early design phases are only rarely supported and information technology is therefore not exploited to its full potential. The early design phases are characterized by an iterative process of searching for plausible solutions. A common approach is to refer to similar examples, which are conventionally found using keyword-based search strategies.To this end we propose a method for indexing spatial configurations along with a sketch-based input method for search strategies that uses so-called semantic fingerprints of buildings. The topology of spatial configurations is extracted from building information models and represented as graphs. For both building information models and the user sketches, the extracted graphs are used as the basis for a subgraph-matching algorithm facilitating an intuitive novel query method for researching similar reference examples. The system is able to present corresponding existing solutions to even rudimentary sketches or fragments of a design idea. In addition to graph matching and sketch-based interaction, more recent BIM-based approaches are also taken into account.     

A BIM-Oriented Model for supporting indoor navigation requirements

Existing indoor navigation approaches such as navigation based on 2D geometries and pre-defined routing remain insufficient for many applications such as emergency response, delivery, utility maintenance and facility management. The insufficiencies caused by existing navigation approaches can be overcome by making use of the advanced semantic and geometric information included in intelligent building models. A key example of such models is Building Information Models (BIMs) which contain detailed geometric and semantic information about buildings. In fact, the BIMs’ structure is very complex for facilitating navigation. This paper presents a new BIM Oriented Modeling methodology resulting in the definition of a new BIM based model (BO-IDM) dedicated for facilitating indoor navigation. The paper later describes the transformation of information from a standard BIM (IFC) into the new model (BO-IDM). The innovation aspects of BO-IDM can be summarized as follows: (i) it provides highly detailed semantic information for indoor navigation and (ii) it represents the non-geo-referenced structure and complex geometries of BIMs with ISO 19107 compliant representations. Therefore this model is well suited for indoor navigation.     

A type-2 fuzzy system-based approach for image data fusion to create building information models

Building Information Modelling (BIM) is a standard digital process that fuses buildings information from different sources into a 3D model during their lifecycle. For new construction sites using BIM, it is possible to monitor the cost, schedule, and changes throughout the lifecycle; however, existing buildings do not have a BIM model. Manually creating the BIM models for existing buildings is a high-cost task, both in time and money, hence there is a need for extracting information from available paper-based documentation and fuse it into a BIM model. The struggle of facility management and utility companies to fully adopt a BIM process (due to their high volumes of paper-based documentation of existing buildings) has led to the research on creating these 3D BIM models from 2D floor plan images.This paper presents a novel processing pipeline to extract 2D digital information from floorplans, fusing it into a 3D BIM model. The work focuses on fusing the available information to create the structure of the building in BIM format, which is considered the essential step before looking on working with other sources of data. In this process, we introduce a type-2 fuzzy logic based Explainable Artificial Intelligence (XAI) approach for the semantic segmentation step. The approach consists of using the outputs of type-2 fuzzy logic systems to classify a pixel as wall or background, by using information around and from the pixel of interest as the inputs to the system. After the semantic segmentation step, the output of the type-2 fuzzy logic goes through a noise removal process and finally a transformation from 2D to 3D by assigning the corresponding BIM tag to each identified element. The proposed type-2 fuzzy logic semantic segmentation approach produced comparable results (97.3% mean Intersection over Union (IoU) performance metric value) to the opaque box model approach based on Convolutional Neural Network (CNN) (99.3% mean IoU performance metric value). However, the type-2 fuzzy XAI system benefits from being an augmentable and interpretable model, which means that human users can understand the decision process and modify the model using their expert knowledge.     

Automatic design and planning of scaffolding systems using building information modeling

Considering their significant impact on construction projects, scaffolding as part of the temporary facilities category in construction must be thoroughly designed, planned, procured, and managed. The current practices in planning and managing scaffolding though is often manual and reactive, especially when a construction project is already underway. Widespread results are code compliance problems, inefficiency, and waste of procuring and managing material for scaffolding systems. We developed a rule-based system that automatically plans scaffolding systems for pro-active management in Building Information Modeling (BIM). The scope of the presented work is limited to traditional pipe and board scaffolding systems. A rule was prepared based on the current practice of planning and installing scaffolding systems. Our computational algorithms automatically recognize geometric and non-geometric conditions in building models and produce a scaffolding system design which a practitioner can use in the field. We implemented our automated scaffolding system for a commercially-available BIM software and tested it in a case study project. The system thoroughly identified the locations in need of scaffolding and generated the corresponding scaffolding design in BIM. Further results show, the proposed approach successfully generated a scaffolding system-loaded BIM model that can be utilized in communication, billing of materials, scheduling simulation, and as a benchmark for accurate field installation and performance measurement.     

BIM 空间关系数据的云存储与检索方法研究

随着工程项目体量的增大,模型中存在的空间关系更加复杂多样化,现有的建筑 信息模型(BIM)数据存储和检索方式无法满足使用要求。为了提高 BIM 中大量空间关系数据的 存储和检索效率,通过集成 BIM 与云计算技术,提出了一种 BIM 分布式负载均衡集群方案, 在此基础上利用弹性搜索框架(Elastic Search)和图数据库Neo4j实现了IFC空间关系数据的云存 储和检索,为海量 BIM 空间关系数据提供一种高效快速的云存储和检索方法。     

Automated classification of building information modeling (BIM) case studies by BIM use based on natural language processing (NLP) and unsupervised learning

This paper comparatively analyzes a method to automatically classify case studies of building information modeling (BIM) in construction projects by BIM use. It generally takes a minimum of thirty minutes to hours of collection and review and an average of four information sources to identify a project that has used BIM in a manner that is of interest. To automate and expedite the analysis tasks, this study deployed natural language processing (NLP) and commonly used unsupervised learning for text classification, namely latent semantic analysis (LSA) and latent Dirichlet allocation (LDA). The results were validated against one of representative supervised learning methods for text classification—support vector machine (SVM). When LSA and LDA detected phrases in a BIM case study that had higher similarity values to the definition of each BIM use than the threshold values, the system determined that the project had deployed BIM in the detected approach. For the classification of BIM use, the BIM uses specified by Pennsylvania State University were utilized. The approach was validated using 240 BIM case studies (512,892 features). When BIM uses were employed in a project, the project was labeled as “1”; when they were not, the project was labeled as “0.” The performance was analyzed by changing parameters: namely, document segmentation, feature weighting, dimensionality reduction coefficient (k-value), the number of topics, and the number of iterations. LDA yielded the highest F1 score, 80.75% on average. LDA and LSA yielded high recall and low precision in most cases. Conversely, SVM yielded high precision and low recall in most cases and fluctuations in F1 scores.     

基于区块链的建筑信息模型图纸多人协同创作系统

建筑信息模型（BIM）图纸多人协同创作在大型建筑项目中很重要,而现有的基于Revit等建模软件或云服务的BIM图纸多人协同创作方法存在BIM图纸版本混乱、不易溯源以及数据安全风险等问题。针对这些问题,设计了一种基于区块链的BIM图纸多人协同创作系统。该系统采用链上链下协同的存储方式,使用区块链和数据库分别存储BIM图纸创作过程中每次创作后的BIM图纸信息以及完整BIM图纸,利用区块链去中心化、可追溯和防篡改的特性保证BIM图纸的版本清晰,并为以后的版权划分提供依据,而且提升了BIM图纸信息数据的安全性。实验结果表明,该系统在多用户并发情况下的平均出块时间为0.467 85 s,系统的最大处理速率为每秒1 568次交易,验证了该系统是可靠的,且可以满足实际应用场景的需求。     

基于空间形态数据的铁路通信数字工程设计系统

建筑信息模型 (building information modeling, BIM)技术作为建筑业实现信息化数字化转型的核心技术, 在铁路建设全生命周期中具有很高的研究价值. 在铁路通信机械室内、站场、区间设计中, 将铁路通信实体的空间位置、形状、大小、关系等空间形态描述数据化, 结合铁路通信设计规范、相关铁路BIM标准以及专业实际设计需求, 研究开发出铁路通信数字工程设计系统. 本系统以空间形态数据为支撑, 铁路工程实体结构分解标准为基础, 在三维环境下实现了铁路通信机械室内机柜设备的智能布设, 站场通信沟槽线缆的路径规划, 区间通信信息点位置的准确布置. 系统进一步基于数字工程模型和图论基本原理, 实现了从数字工程模型中获取逻辑关系并生成通信逻辑网图. 经实际工程验证, 系统对铁路通信数字工程设计效率和准确率都有较大提升, 从工程源头实现了铁路通信工程数字化成果交付和应用, 促进了铁路通信工程项目全过程技术升级和数字化模式革新.     

基于BIM模型的结构设计审查方法研究

建筑信息模型(BIM)作为建筑工程的数字化表达,正在成为实现建筑全生命期信息化、工业化和 智能化的重要手段。以 BIM 模型作为设计交付成果是未来建筑设计领域发展趋势。然而,现阶段建筑结构设 计的审查工作还是以人工手动审查为主,普遍存在主观、效率偏低且易出差错等问题。因此,以框架结构模型 审查为实例,通过关系数据库方法解析 BIM 模型数据,采用 Java 编程转译结构设计规范条文,提出一种基于 BIM 模型的结构设计审查方法。实现过程包括：①模型准备与信息映射;② 规范条款分类和转译;③ 建立连 接和代码执行。结果表明：该方法可以部分实现结构模型的自动化审查,提高了设计审查工作的科学性、可靠 性和规范性,为今后全面实现设计审查的自动化和智能化提供了技术基础和参考方法。     

BIM reconstruction from 3D point clouds: A semantic registration approach based on multimodal optimization and architectural design knowledge

Reconstructing semantically rich building information model (BIM) from 2D images or 3D point clouds represents a research realm that is gaining increasing popularity in architecture, engineering, and construction. Researchers have found that architectural design knowledge, such as symmetry, planarity, parallelism, and orthogonality, can be utilized to improve the effectiveness of such BIM reconstruction. Following this line of enquiry, this paper aims to develop a novel semantic registration approach for complicated scenes with repetitive, irregular-shaped objects. The approach first formulates the architectural repetition as the multimodality in mathematics. Thus, the reconstruction of repetitive objects becomes a multimodal optimization (MMO) problem of registering BIM components which have accurate geometries and rich semantics. Then, the topological information about repetition and symmetry in the reconstructed BIM is recognized and regularized for BIM semantic enrichment. A university lecture hall case, consisting of 1.9 million noisy points of 293 chairs, was selected for an experiment to validate the proposed approach. Experimental results showed that a BIM was satisfactorily created (achieving about 90% precision and recall) automatically in 926.6 s; and an even more satisfactory BIM achieved 99.3% precision and 98.0% recall with detected semantic and topological information under the minimal effort of human intervention in 228.4 s. The multimodality model of repetitive objects, the repetition detection and regularization for BIM, and satisfactory reconstruction results in the presented approach can contribute to methodologies and practices in multiple disciplines related to BIM and smart city.     

Processing of Topological BIM Queries using Boundary Representation Based Methods

Building Information Models (BIM) are comprehensive digital representations of buildings, which provide a large set of information originating from the different disciplines involved in the design, construction and operation processes. Moreover, accessing the data needed for a specific downstream application scenario is a challenging task in large-scale BIM projects. Several researchers recently proposed using formal query languages for specifying the desired information in a concise, well-defined manner. One of the main limitations of the languages introduced so far, however, is the inadequate treatment of geometric information. This is a significant drawback, as buildings are inherently spatial objects and qualitative spatial relationships accordingly play an important role in the analysis and verification of building models. In addition, the filters needed in specific data exchange scenarios for selecting the information required can be built by spatial objects and their relations. The lack of spatial functionality in BIM query languages is filled by the Query Language for Building Information Models (QL4BIM) which provides metric, directional and topological operators for defining filter expressions with qualitative spatial semantics. This paper focuses on the topological operators provided by the language. In particular, it presents a new implementation method based on the boundary representation of the operands which outperforms the previously presented octree-based approaches. The paper discusses the developed algorithms in detail and presents extensive performance tests.     

基于IFC 与gbXML 标准的建筑信息模型与绿色建筑分析软件互操作性测试与评估

绿色建筑和建筑节能是建筑行业可持续发展的重要因素,然而建筑信息模型(BIM) 软件种类繁多、数据标准各异、软件之间的数据传递经常丢失信息。为解决不同软件之间的“信 息孤岛”问题和互操作性问题,分析了基于工业基础类标准(IFC)和gbXML 标准的绿色建筑模型 的结构框架,选取BIM 建模软件ArchiCAD 和绿色建筑性能分析软件Ecotec,对基于IFC 和 gbXML 标准的软件之间的互操作性进行了测试和评估,确定了建筑信息模型在交互过程中的问 题。针对相关问题本文提出了减少IFC 标准中的信息冗余、提高IFC 标准领域层对绿色建筑信 息的支持、提高资源层对相关信息定义的针对性等建议。