Integrating BIM with building performance analysis in project life-cycle

Adopting Building Information Modelling (BIM) in Building Performance Analysis (BPA) is becoming an emerging research area in the application of information technology in the Architecture, Engineering, and Construction (AEC) industry. To investigate the current state of research in the adoption of BIM in BPA, this study performed a holistic review consisting of a bibliometric analysis of existing literature, content analysis of selected studies, as well as follow-up qualitative discussion in BIM integration with BPA. The bibliometric analysis identified 60 relevant studies; the content analysis of these studies revealed the research focuses of BIM-enabled BPA, including interoperability, semantics, and sustainability rating systems; the qualitative discussion further highlighted the learning process throughout project delivery stages and addressed the potential gap between ‘as-designed’ building performance and ‘as-built’ performance. Overall, this study contributes to existing research by identifying key input attributes and workflow in BPA, reviewing the state-of-the-art research on BIM integration with BPA, and investigating the major research areas, namely, interoperability issues in BIM-enabled BPA within the context of life-cycle BPA

Text mining-based patent analysis of BIM application in construction

As a data tool applicable to the full life-cycle of construction engineering and management, Building Information Modeling (BIM) has great potential for significantly increasing project productivity and performance. Awareness of BIM application hotspots and forecasting its trends can drive innovations in construction field. Using patents as data resources, this study develops an effective framework integrating the citation network analysis and the topic clustering technology to identify BIM application information and forecast its trends. This framework comprises three-step analysis:(1) quantitative characteristic analysis of patent outputs; (2) Social Network Analysis (SNA)-based co-occurrence network analysis; and (3) identification of BIM topics using a Latent Dirichlet Allocation (LDA). Finally, the case demonstrates the effectiveness of this framework contributing to promote technological development and innovation of BIM. The contributions of this study are threefold: (1) an innovative text mining-based framework for BIM patent analysis in construction is developed; (2) patents that have focused on identifying the application hotspots and development trend of BIM in accordance with our developed framework are reviewed; and (3) a signpost for technological development and innovation of BIM is provided

Patent cooperative patterns and development trends of Chinese construction enterprises: A network analysis

Despite the rapid development of Chinese construction industry, there has been little research effort directed towards exploring patent cooperative patterns and evolution trends of construction enterprises, especially from the perspective of the patent development network. This paper extracts implicit collaborative information and introduces Social Network Analysis (SNA) method to conduct the patentometric analysis based on patent data from the “Top 500 Chinese Construction Enterprises” sourced from PatSnap database. The enterprise-enterprise networks and enterprise-university networks are analyzed quantitatively. The results reveal that: 1) there is a rising trend in the number of patents and patentees; 2) state-owned enterprises play a dominant role in patent development; 3) most of patents are classified as International Patent Classification E04G21; 4) the cooperative relationships are mainly within enterprises and their subsidiaries; 5) when enterprises choose to cooperate with universities, in addition to professional qualification, geographical factors should also be considered. Finally, the development and patent evolution trends are discussed. Some useful suggestions are proposed. The contribution lies in: (a) providing a visualization of the implicit collaboration information of patents in Chinese construction enterprises; (b) revealing cooperative patterns of construction enterprises on patents; and (c) providing enterprises some useful suggestions for patent cooperation

Effects of physical fatigue on the induction of mental fatigue of construction workers:A pilot study based on a neurophysiological approach

Within a dynamic and complex working environment, fatigue statuses (involving physical and mental fatigue) of workers on construction sites tend to have a more serious impact on work performance than general workplaces. To improve safety management on sites, valid fatigue management measures for workers are urgently required. Specifically, there are construction activities requiring both physical and cognitive effort. As a critical premise for putting forward feasible fatigue management measures, correlations between physical and mental fatigue on work performance should be identified. This research explored the effects of physical fatigue on the induction of mental fatigue of construction workers, by adopting a pilot experimental method. Manual handling tasks of different intensities were firstly designed for stimulating certain expected physical fatigue statuses. A cognition-required risk identification task was then arranged for inducing mental fatigue, during which a wearable electroencephalogram (EEG) sensor was utilized for fatigue detection and measurement. Through a comprehensive data analysis method based on EEG rhythms, it was found that the high physical fatigue can significantly accelerate the induction of mental fatigue. Considering the resource allotment, more vigilant and attentional resources were required during the intensive manual handling tasks for the highly controlled limbs and the mind to steps. Thus, additional resources were invested to maintain the same level of cognitive performance in the risk identification tasks, which led to the increased mental fatigue. In practice, the heavy physical task can be regarded as one of the factors affecting the development of mental fatigue status, and therefore impairing cognitive functioning and other mental performances of the brain. The pilot study results provided a reference for fatigue management of construction workers to promote comprehensive safety management on construction sites

Highway Planning and Design in the Qinghai–Tibet Plateau of China: A Cost–Safety Balance Perspective

Engineering designs for mountainous highways emphasize compliance checking to ensure safety. However, relying solely on compliance checking may lead designers to minimize costs at the expense of high risk indicators, since the overall risk level of the highway design is unknown to the designers. This paper describes a method for the simultaneous consideration of traffic safety risks and the associated cost burden related to the appropriate planning and design of a mountainous highway. The method can be carried out in four steps: First, the highway design is represented by a new parametric framework to extract the key design variables that affect not only the life-cycle cost but also the operational safety. Second, the relationship between the life-cycle cost and the operational safety risk factors is established in the cost-estimation functions. Third, a fault tree analysis (FTA) is introduced to identify the traffic risk factors from the design variables. The safety performance of the design solutions is also assessed by the generalized linear-regression model. Fourth, a theory of acceptable risk analysis is introduced to the traffic safety assessment, and a computing algorithm is proposed to solve for a cost-efficient optimal solution within the range of acceptable risk, in order to help decision-makers. This approach was applied and examined in the Sichuan–Tibet Highway engineering project, which is located in a complex area with a large elevation gradient and a wide range of mountains. The experimental results show that the proposed approach significantly improved both the safety and cost performance of the project in the study area. Keywords: Highway planning and design, Cost–safety optimization, Acceptable risk assessment, Sichuan–Tibet Highwa

Comparative Experiments to Assess the Effects of Accumulator Nitrogen Injection on Passive Core Cooling During Small Break LOCA

The accumulator is a passive safety injection device for emergency core cooling systems. As an important safety feature for providing a high-speed injection flow to the core by compressed nitrogen gas pressure during a loss-of-coolant accident (LOCA), the accumulator injects its precharged nitrogen into the system after its coolant has been emptied. Attention has been drawn to the possible negative effects caused by such a nitrogen injection in passive safety nuclear power plants. Although some experimental work on the nitrogen injection has been done, there have been no comparative tests in which the effects on the system responses and the core safety have been clearly assessed. In this study, a new thermal hydraulic integral test facility—the advanced core-cooling mechanism experiment (ACME)—was designed and constructed to support the CAP1400 safety review. The ACME test facility was used to study the nitrogen injection effects on the system responses to the small break loss-of-coolant accident LOCA (SBLOCA) transient. Two comparison test groups—a 2-inch cold leg break and a double-ended direct-vessel-injection (DEDVI) line break—were conducted. Each group consists of a nitrogen injection test and a nitrogen isolation comparison test with the same break conditions. To assess the nitrogen injection effects, the experimental data that are representative of the system responses and the core safety were compared and analyzed. The results of the comparison show that the effects of nitrogen injection on system responses and core safety are significantly different between the 2-inch and DEDVI breaks. The mechanisms of the different effects on the transient were also investigated. The amount of nitrogen injected, along with its heat absorption, was likewise evaluated in order to assess its effect on the system depressurization process. The results of the comparison and analyses in this study are important for recognizing and understanding the potential negative effects on the passive core cooling performance caused by nitrogen injection during the SBLOCA transient

Urban Traffic Operation Pattern and Spatiotemporal Mode Based on Big Data (Taking Beijing Urban Area as an Example)

An analysis of urban traffic operation pattern and spatiotemporal mode is an important basis to solve the problems of traffic congestion, emergency and extreme weather. Traditional studies on the urban traffic operation pattern and spatiotemporal mode usually are restricted by issues as poor time effectiveness, large space scale and coarse time granularity of traffic flow data, thus this essay choose to use the urban traffic speed data based on floating vehicle trajectory to dissect the urban traffic operation pattern and spatiotemporal mode in Beijing in a multi-dimensional and fine granularity. Differences of features in weekdays and weekends are also compared. This paper reports that âtwo-peakâ mode is obvious in the urban traffic condition. Besides, the morning peak of weekends is postponed to 11-12 am, and the night peak appears shorter in 5 pm compared to weekdays. Finally, four modes of traffic and its driving mechanism are concluded

An Ontological Metro Accident Case Retrieval Using CBR and NLP

Metro accidents are apt to cause serious consequences, such as casualties or heavy economic loss. Once accidents occur, quick and accurate decision-making is essential to prevent emergent accidents from getting worse, which remains a challenge due to the lack of efficient knowledge representation and retrieval. In this research, an ontological method that integrates case-based reasoning (CBR) and natural language processing (NLP) techniques was proposed for metro accident case retrieval. An ontological model was developed to formalize the representation of metro accident knowledge, and then, the CBR aimed to retrieve similar past cases for supporting decision-making after the accident cases were annotated by the NLP technique. Rule-based reasoning (RBR), as a complementary of CBR, was used to decide the appropriate measures based on those that are recorded in regulations, such as emergency plans. A total of 120 metro accident cases were extracted from the safety monthly reports during metro operations and then built into the case library. The proposed method was tested in MyCBR and evaluated by expert reviews, which had an average precision of 91%

Optimal camera placement for monitoring safety in metro station construction work

Monitoring systems based on cameras are crucial for safety management of the high-risk activities common in the complex environment of metro station construction sites, and hence there is a need for a reliable camera network system. However, the number and locations of cameras are currently estimated according to the experience of managers/engineers, and the occlusion effect is rarely considered, resulting in weak coverage of 3D spaces in practice. To address this gap, a novel approach is presented to optimize camera placements for 100% site coverage while considering the occlusion dynamics caused by sidewalls and supports during excavation in metro station projects. A case study of a metro station project is presented to demonstrate and validate the approach, with results showing that the optimized plans for camera placement have larger coverage than the original plan and better performance in safety monitoring and controlling hazards. Optimized in this way, the plans for camera placement can help managers with effective planning and enhanced safety management of metro station construction sites.</p