Automated planning support for on-site construction inspection

Construction inspectors need inspection planning assistance to specify goals for inspection and to develop and search among feasible inspection plans that inspectors can implement to address these inspection goals on construction sites. This paper presents the details of an automated planning approach to support on-site construction inspections and thereby permit inspectors to both generate complete, detailed inspection plans and to consider numerous possible alternatives in detail. The approach consists of representations and reasoning mechanisms to develop inspection goals and plans, and to support consideration of multiple possible inspection plans. In particular, the approach consists of a series of matching processes, facilitated by faceted classification reasoning, and a generative method-based approach to inspection planning that features a measurement distribution concept to permit various approaches for distributing measurements throughout components. The authors present an object-oriented prototype to illustrate and demonstrate this approach, together with detailed validation discussions that utilize inspection scenarios documented in construction inspection literature to demonstrate the generality and applicability of the developed approach.     

Risk-chasing behaviour in on-site construction decisions

Risk-chasing behaviour in on-site construction decision-making can result in illogical decisions and, thus, significant project losses. Accordingly, the authors conducted a set of experiments in order to detect the existence of such behaviour under a range of typical project conditions within a set of common situations. Fifty-three project leaders participated in the experiments by making choices framed by a set of 24 questions. Each question related to a known behavioural tendency, included the influence of an external parameter, and contained information from which expected values could be derived. Participants were well distributed by geography, age and experience. Contrary to the common perception that construction decision-makers are relentlessly risk-averse, they demonstrated risk-chasing behaviour when the decision occurred in over-budget project conditions. Younger participants were even more risk chasing in such conditions. Understanding and identifying where such behaviour occurs could ultimately lead to the development of means of avoiding the resulting losses.     

浅谈现场施工管理

结合多年的现场施工管理实践经验,对现场施工的人员管理、技术、材料机械、资料管理、成品保护、施工安全等问题进行了阐述,为工程项目的施工管理提供了依据。     

Formalisms for query capture and data source identification to support data fusion for construction productivity monitoring

Productivity monitoring, which involves frequent monitoring and analysis of on-going construction activities, helps in assessing a project's performance and in enabling identification of opportunities for improvement. It often involves finding answers for dynamic user queries that require data to be fused from different combinations of heterogeneous data sources having different levels of detail, representations and reference systems. Digital elements of these sources are expanding exponentially, and yet fusing and processing them manually remains a challenging problem. In this paper, the authors present a formal approach for capturing dynamic user queries and identifying applicable sets of data sources from a given set of available data sources to answer such queries. This approach is an important step to enable automated and efficient multi-source data fusion.     

SMA施工控制与现场监理

介绍了SMA的制拌、摊铺和碾压成型的方法,阐述了SMA混合料沥青含量的控制措施,论述了SMA的施工现场监理措施,以满足沥青路面的要求,确保高速公路社会效益的实现。     

Assessing the impact of materials tracking technologies on construction craft productivity

Even though previous studies indicate that construction labor productivity can benefit from automated tracking technologies for field materials management purposes, the actual impact of these technologies on construction productivity has not been fully investigated. This study attempted to quantify the productivity impact of automating the identification and localization of engineered components on industrial sites. For this purpose, an extensive field trial was conducted on a power-plant project. Data from both a traditional tracking process and an automated tracking process designed for the purposes of this study were collected. By considering the traditional tracking process as the baseline for comparison, this study quantified and assessed the impact of the automated tracking methodology. The results indicate that materials tracking technologies can significantly improve craft labor productivity.     

工程监理中的安全控制和现场文明施工控制

结合工程建设监理制度的实行,分析了监理工作中安全控制和现场文明施工控制的重要性,并就如何实施安全和现场文明施工的监理提出了具体做法,指出要搞好施工必须有安全文明的施工环境.     

Autonomous production tracking for augmenting output in off-site construction

Problems in existing methods of production tracking in off-site construction result in schedule delays and increased costs. To eliminate these deficiencies, an autonomous production tracking that analyzes real-time production data is proposed. A specific implementation of the proposed production tracking mechanisms has been developed for a large off-site construction plant in Australia, and is in the process of installation. The paper shows that: (i) The production model in off-site construction is always nonlinear in the outcome due to the presence of variability (ii) in systems with a periodic production target, deviation from the schedule converges to zero at the end of production period and the same downward trend should be followed in designing plan buffers and (iii) long-term production performance in off-site construction can autonomously be monitored and controlled by observing critical variables of production. The paper provides those who manage off-site construction with recommendations on effective production tracking and management. The models and propositions in this research are of practical value and can be used to detect impending production shortfalls against periodic targets in the short-term, and adjust capacity parameters and production targets in long-term planning.     

Comparative study of vision tracking methods for tracking of construction site resources

Vision tracking has significant potential for tracking resources on large scale, congested construction sites, where a small number of cameras strategically placed around the site could replace hundreds of tracking tags. The correlation of vision tracking 2D positions from multiple views can provide the 3D position. However, there are many 2D vision trackers available in the literature, and little information is available on which one is most effective for construction applications. In this paper, a comparative study of various vision tracker categories is carried out, to identify which one is most effective in tracking construction resources. Testing parameters for evaluating categories of trackers are identified, and benefits and limitations of each category are presented. The most promising trackers are tested using a database of construction operations videos. The results indicate the effectiveness of each tracker in relation to each parameter of the test, and the most suitable tracker needed to research effective 3D vision trackers of construction resources.     

Design criteria for impact factors based on dynamic on-site data in railway bridges

To evaluate the dynamic behaviours of bridges, many researchers have analysed interactions between vehicles and bridges with numerical methods instead of field loading tests. However, conventional numerical methods take too much time and cost to evaluate the impact factor of bridges in design and maintenance practice. The objective of this study was to propose improved design criteria by using impact factors based on natural frequency rather than span length of railway bridges using dynamic field load-carrying capacity test database. The improved design criteria use a different methodology than that outlined in the International Union of Railway specifications Code. Statistical regressions are applied to more easily estimate the natural frequency of a bridge with a span length of 20?m or longer with steel plate girder or truss superstructures. Calculated impact factors were compared to impact factors obtained from field measurements. Results indicated that the improved method could provide a very reliable estimation for actual impact factors. Since the suggested impact factor criteria are conservative, the proposed method can be used in design and management stages to consider dynamic effects of railway bridges in a more intuitive manner.     

基于现场监测数据的隧道围岩变形特性研究

 隧道变形是衡量隧道结构体系稳定性的重要指标,该指标可以科学、及时、可靠、便捷地反映隧道工程的安全性。在收集、整理我国103座山岭隧道836个拱顶沉降数据、806个水平收敛数据的基础上,系统分析围岩变形量、围岩变形稳定时间与围岩级别、隧道开挖面积等因素之间的关系。研究表明：隧道围岩变形数据主要集中在低值区间,中高值区间数据较少但分布范围较广,随着围岩级别增大,围岩变形值增大,数据集中区间增大,变形分布区间增大;隧道断面面积对隧道围岩变形影响较大,随着隧道断面面积的增大,变形值增大;实测数据表明,隧道围岩变形与隧道埋深并没有明显的联系;隧道围岩变形稳定时间主要集中在中低值区间,高值区间的数据相对较少,随着围岩级别增大,围岩变形稳定时间增大,分布区间增大。根据统计结果,提出不同围岩级别下,隧道变形的建议控制值以及变形稳定时间参考值。     

建筑材料在建筑节能中的作用

简述了发展节能与绿色建筑的紧迫性，论述了节能建材的现状，探讨了节能建材的经济前景，分析了节能建材在推广使用中存在的问题，以实现我国社会和经济的可持续发展。     

Onsite 3D marking for construction activity tracking

This article presents an innovative onsite 3D marking approach for tracking the progress of construction activities using an Ultra Wide Band (UWB) positioning system. The 3D marking approach is used to track activities that could not be tracked previously using object-based tracking models, including welding and inspection activities for pipelines. A field experimentation study on an industrial-type building construction project was conducted to demonstrate the method and evaluate its performance in a construction environment and a software application was developed using MATLAB to automate the data analysis and progress estimation procedure. The results of the field experiments confirmed the feasibility of the developed 3D marking approach for tracking a number of construction activities, such as welding and inspection, which are not associated with the addition or movement of objects on a site and therefore could not be tracked using traditional object-based models.     

建筑节能促进新型建材的发展

主要论述了新型建材的发展必须与建筑节能结合,必须具有生态、环境和节能意识。加速发展节能、节土、利废的各种新型墙体材料,不仅是建材工业节能和调整结构的重要措施,而且对改善建筑功能,节约土地具有十分重要的意义。     

Evolution of the crane selection and on-site utilization process for modular construction multilifts

Modular construction technology has been used in building construction for decades, having been widely utilized on sites with high traffic volume, restricted accessibility/storage, or business operations which cannot be interrupted by long construction time. A key challenge in this method of construction lies in planning and executing lifts within a short timeframe. In this regard, proper crane selection and site layout optimization can significantly increase productivity and shorten the lifting schedule. This paper thus proposes a methodology for the crane selection process and introduces mathematical algorithms to assess the construction of multi-lift operations. The modular lift process is divided into three stages: crane load and capacity check, crane location, and boom and superlift clearance. Each stage's parameters are introduced, analyzed, and graphically explained. The methodology logic is supported by a generalized mathematical algorithm and is applied and tested on a case study involving the construction of five three-storey dormitories in 10 working days for Muhlenberg College in Allentown, Pennsylvania.     

监控量测数据在隧道工程数值计算中的应用

介绍了监控量测数据处理方法,并对如何运用监控量测数据进行反分析计算进行了分析,最后对规范规定与反分析计算得到的地层参数进行了对比,结果基本符合,为进一步分析结构稳定性和支护结构的工作状态奠定了基础。     

施工期预应力混凝土梁受力性能实测

以混凝土结构的时变特性为基础,制定施工期预应力混凝土梁的实测方案和内容,通过原位实测,选择施工期预应力混凝土梁的实测工况,根据实测数据,分析预应力梁在施工期各工况的受力重分布规律。通过分析,指出了施工工序对施工期预应力混凝土结构受力性能的影响规律,实测数据证明了预应力筋张拉对施工期结构受力性能重调整的影响程度在10%～25%之间。该实测试验及相应结论为施工期预应力混凝土结构性能的受力分析和安全控制提供了实测依据。     

现浇钢筋混凝土外墙保温施工

个绍了舒乐舍板的计料性能和工艺特点，结合实际工裎施工，就舒乐舍板外墙外保温的施工工艺及抹灰措施进行了论述，并总结了几点施工体会。     

现场预制钢筋混凝土箱体结构顶进法施工

以公路下穿铁路现场整体预制箱形框构桥为例，对顶进法施工的特点、工艺原理、施工工艺等作了详细阐述，提出了顶进系统施工的质量控制及安全措施。