Vision-based integrated mobile robotic system for real-time applications in construction

To increase the degree of automation and frequency of data collection for monitoring construction sites, there has been a rapid increase in the number of studies, in the past few years, that developed and/or examined mobile robotic applications in construction. These vision-based platforms capable of autonomous navigation and scene understanding are becoming essential in many construction applications, namely construction sites surveying, work-in-progress monitoring, and existing structure inspection. Simultaneous Localization and Mapping (SLAM) and object recognition for proper context-aware motion planning are some of the core vision techniques that are driving innovation for these robotic systems. To characterize the limitations of current techniques on real-time performance and identify challenges in integration and implementation for construction applications, this paper proposes a mobile robotic platform that incorporates a stack of embedded platforms with integrated Graphical Processing Units (GPUs). This paper presents three case studies to evaluate the performance of the proposed system. The results demonstrate the robustness and feasibility of developing and deploying an autonomous system in the near future.     

浅谈地质雷达数据的精细处理

地质雷达在基础建设中被广泛应用,但由于其发射的为高频电磁波,数据采集极易收到外界干扰。本文通过一个干扰条件下采集的典型的地质雷达剖面,运用峰值分析、f-k滤波、预测反褶积、小波分析等方法,对干扰剖面进行了依次分析处理,并对某一方法多次运用,有效地剔除了干扰信息,突出了有效信息,达到了数据精细处理的目的。     

A new simplified thermal design tool for architects

Architects form an integral link in the design of efficient buildings. Energy-efficient design strategies therefore, require architects and engineers to work closely together in optimising the building shell. However, this is not always practical. Architects must therefore, be able to perform a preliminary thermal analysis if energy efficient design strategies are to succeed. Existing tools do not cater for them or fit their design methodology. A need therefore exists for a simplified thermal design tool for architects. This article discusses the development of a tool to fulfil this requirement.     

A semi-automatic processing and visualisation tool for ground-penetrating radar pavement thickness data

Ground-penetrating radar (GPR) is a recommendable and cost-effective non-destructive technique for measuring the thickness of pavement layers because data acquisition can take place at normal traffic speeds. On the other hand, the large amount of data collected is difficult to process. Given that processing is conducted by qualified practitioners, it is a key to obtain software tools that allow for accurate thickness measurements and fast processing times. This paper presents a new semi-automatic program for the processing and visualisation of GPR data to measure pavement thicknesses. The results showed that an optimisation in the execution time allowed for a near-immediate response in data processing even when dealing with large data sets. Different data set lengths, ranging from 100 m to 20 km, were analysed, and the processing times required to complete the entire process were examined taking into account three different hardware configurations (i3, i5 and i7 processors). In all cases, the processing times did not exceed 30 s. An additional test was performed to evaluate the reproducibility of the algorithm on a well-defined and preconditioned concrete asphalt course. Furthermore, the visualisation application allows for the georeferencing of the field GPR data by using additional GPS data.     

数据成批处理技术在施工放样中的应用研究

详细地阐述了如何利用AutoCAD和Excel进行测量数据汇总、处理,分析并进行模拟放样检验,介绍了利用数字全站仪进行坐标法工程施工放样的方法,并说明了此方法在北京北站改建工程中的应用情况。     

地质雷达在地铁隧道施工中的应用

介绍了地质雷达仪器的特点和作业方法,分析了地质雷达的探测原理,并结合北京地铁工程实例,总结了地质雷达在实际工程应用中的优点,指出其在地下工程勘察和施工领域具有广泛的应用前景。     

某隧道施工量测数据处理方法讨论

通过对某隧道工程概况的分析,对隧道穿越F7断层时施工量测数据处理方法进行了讨论,并对量测数据进行了回归分析,表明围岩的变形规律可以用回归曲线的方法来描述。     

A simplified method for determining sway in reinforced concrete dual buildings and design applications

Sway analyses of reinforced concrete buildings generally are carried out with computer programs. However, as the number of iterative solutions increase, the process may become tedious. This paper proposes a simple analytical method to evaluate sway of dual buildings subject to various types of lateral loads. The proposed method is based on the continuum model. Story drift limited by building codes can be controlled by the proposed method. Likewise, design engineers can use the simple analytical expressions to calculate the stability index, which includes sway terms at each story level. Stability index equation without sway terms is obtained by using the developed analytical expressions. Use of the equation, which is free of sway terms, is quite simple. Additionally, by using the proposed method, shear wall–frame interaction can be modeled simply. Thus, moment at the base of shear walls can be determined by using this model. Copyright © 2012 John Wiley & Sons, Ltd.     

建筑工程竣工测量数据处理系统的开发设计

以AutoCAD绘图软件为基础平台,利用.NET技术二次开发了建筑工程竣工测量数据处理系统,并应用于测绘生产,实现了数据自动化处理,同时通过数据检核模块减少了数据处理中出现问题的概率,提高了工作效率和效益。     

A simplified 3D model for tunnel construction using tunnel boring machines

This paper includes a presentation of a simplified three-dimensional numerical model for the prediction of soil movement induced during tunnel construction using tunnel boring machines (TBM). The model is based upon the generalization of the convergence-confinement concept to 3D tunnel construction. It uses two parameters (L_dec and α_dec) which stand for the length of the unlined zone and the partial stress release, respectively. The value of the parameter L_dec can be taken equal to the tunnel diameter, while the value of α_dec can be determined by fitting the model to empirical formula, and then adjusted based on settlement registered during tunnel construction.The capacity of the model is illustrated through an application to a shallow tunnel in soft soil. The comparison of the numerical results to those suggested by different authors shows good agreement.     

A framework for using mobile computing for information management on construction sites

The application of mobile computing in construction is becoming a major research theme in the domain of Information Technology in Construction. However, most research in this area focuses on a detailed aspect or single facet of a mobile computing technology. This paper introduces a framework for the implementation of mobile computing on construction sites, which comprises an application model and a technical model. The application model identifies the features of mobile computing, construction personnel, construction information, and construction sites, and explores the interactions that are likely to affect the implementation of mobile computing. The technological model generalizes mobile computing technologies and gives system designers a clear structure for designing mobile computing systems from a technical perspective. Finally, a case study of a real construction situation is used to validate this framework.     

频谱反演法在探地雷达隧道衬砌检测中的应用研究

隧道衬砌模型的空间结构属于典型的层状分布,采用探地雷达进行隧道二衬检测时,往往很难识别高度小于调谐厚度的脱空。通过建立含有脱空薄层的隧道二衬层状几何模型,结合电磁波在隧道衬砌中的传播规律,给出了隧道衬砌检测时电磁波的反射模型,并推导了其广义反射系数谱域表达式,从而提出一种根据反射系数序列频谱估算隧道二衬厚度及脱空高度的反演方法。通过分析反射系数序列的幅度谱属性,进一步提出一种估计脱空层高度的快速方法,即根据幅度谱凹陷周期确定脱空层双程走时,进而估算脱空层高度。最后,利用1st Opt数学优化分析软件进行全局优化,并反演求解各参数。物理模型实验及现场应用实例的处理结果表明,当脱空厚度小于1/4波长时,本文所述的频谱反演法仍能准确反演出二衬厚度及脱空层高度,从而提高了探地雷达资料的垂直分辨率。     

Real-time resource location data collection and visualization technology for construction safety and activity monitoring applications

Data to field operations of construction resources (personnel, equipment, materials) is vast, but the effort of collecting, analyzing, and visualizing is hardly ever taken. One main reason that limits higher quality in project site management decision making especially in resource intensive and complex operations is access to real-time information and subsequent technology that enables effortless data collection, processing, and visualization. Although recent developments in remote data sensing and intelligent data processing supplement manual data recording and analyze practices, few data on visualization tools in construction exist that gather data from dynamic resources and stream it to a field-realistic virtual reality environment in real-time. State-of-the-art technology in the field of real-time data collection and visualization is reviewed. A novel framework is presented that explains the method of streaming data from real-time positioning sensors to a real-time data visualization platform. Three case studies are presented which highlight its methods for recording data and visualizing information of construction activities in a (1) simulated virtual construction site, (2) outdoor construction setting, and (3) worker training environment. The results demonstrate that important construction information related to both safety and activity in field operations can be automatically monitored and visualized in real-time, thus offering benefits such as increased situational awareness to workers, equipment operators, or decision makers anywhere on a construction project or from a remote location.     

Selection of mobile cranes for building construction projects

The complicated process of selecting cranes for construction projects can be divided roughly into two main phases: (1) a general decision on the type of crane, mobile or tower; and (2) selection of the particular model according to the required size and technical specification. Several determinants of this second phase of the selection process in a typical mobile crane culture were investigated through on-site interviews with representatives of major construction companies. Factors affecting mobile crane selection were identified, classified, and rated according to their degree of influence. The involvement in equipment planning and crane selection was characterized with regard to project stages and planning parties. The findings were analysed with a view to the changing participation level of each party throughout project life. The conclusions of the study portray a picture that is different from the common assumptions about mobile crane selection, with respect to both influencing factors and the process itself. The study underlines the weight of non-project-specific factors, and shows that equipment planning is not merely a one-time technical exercise executed by a planner, but rather a process carried out throughout project life by a joint effort of several parties.     

移动物资中的RFID数据清洗技术

RFID设备采集原始数据直接应用于上层系统,会造成系统业务逻辑设计困难,也会对系统资源造成浪费。针对此问题,文章对RFID数据传输于上层应用时的流数据进行清洗,处理其中存在的数据冗余问题,为上层应用提供高效、可靠的源数据。     

使用小型机具的混凝土路面接缝施工技术

通过多年的施工经验，根据混凝土路面接缝的种类，总结了小型机具在混凝土路面接缝的施工技术，并介绍了接缝的填封方法，以处理好混凝土路面的接缝质量，保证路面的平整度。     

工程机械随机工具的配置与使用

"工欲善其事,必先利其器".一套得心应手的随机工具对维修人员来说至关重要.然而并不是每一种机器的工具都能满足要求,并且物尽其用.     

Method for developing and updating deterioration models for concrete bridge decks using GPR data

This study presents a workable procedure for developing and updating deterioration prediction models based on the results of a Non-Destructive Evaluation (NDE) technique, Ground Penetrating Radar (GPR). To this end, a system reliability based deterioration model was developed for a simply-supported reinforced concrete bridge deck, designed according to the Canadian Highway Bridge Design Code (CHBDC-S6). The superstructure element-level deteriorated conditions for different time intervals were applied in the non-linear finite element model developed for the entire bridge deck, and the system level reliability indices were estimated accordingly. The salt contamination was assumed to affect the top surface, soffits of the deck, and beams due to infusion of de-icing salt material. The resulting primary deterioration model was updated based on a GPR test localized defect map that was obtained for an existing bridge with similar plan dimensions. The results indicate that the assumed conservative uniformly defected superstructure is reliable in this case, that is, the estimated reliability indices for the uniform and localized defect plans do not differ considerably.