A metadata model for collaborative experiments and simulations in earthquake engineering

Research projects in earthquake engineering yield a very large amount of complex data from experiments and computer simulations. Understanding and exchanging these complicated and voluminous data sets prompted the development of metadata models that document the processes of data generation, and facilitate the collaboration and exchange of information between researchers. The present metadata model was designed to document and exchange a large number of large data files in earthquake engineering, but is applicable to other fields of engineering and science. The model was conceived based on a series of former data models, which were unduly complicated and limited to few types of experiments. Simpler than its predecessors, the present metadata model applies to all kinds of earthquake engineering experiments. It was developed in the object-oriented framework using Protégé. Its applications are illustrated with examples from centrifuge experiments.     

暖通协同CAD开发研究

针对暖通专业无法与土建专业适时同步以及暖通专业自身无法配合而造成设计过程中暖通设计师重复工作量大、效率低等客观现状,提出了协同设计模式下的暖通CAD的开发模型,探讨了暖通协同CAD开发过程中的相关实现技术。     

Environmental contour analysis in earthquake engineering

In many engineering problems the uncertainty in the design and analysis process is dominated by uncertainty concerning the environmentally induced loading on the system. One such type of system is a structure located in high seismic zones, where there is a high level of uncertainty associated with the ground acceleration. In this study the demand caused by the environmental loads is statistically characterized in terms of magnitude, site-to-source distance and attenuation error at a specified structural period. Through the use of a reliability-based procedure known as the Inverse-First Order Reliability Method all of the combinations of the random loading variables that produce a response spectrum with the specified return period may be identified. These infinite number of combinations produce an Environmental Contour that may be derived for the two, three, or four-dimensional case. Because these contours represent an infinite number of combinations of environmental loading random variables, and in turn, a family of response spectra with the same return period, one need only search the Environmental Contour for the response spectrum producing the peak spectral acceleration at the structural period of interest. This study presents a general multi-variate framework focusing on the derivation of these two, three, and four-dimensional Environmental Contours. Initially, the magnitude and site-to-source distance are assumed to be statistically independent. Two and three-dimensional Environmental Contours are derived for this case and critical response spectra for three different, commonly used return periods are examined. Then a hypothetical example in which the site-to-source distance is assumed LogNormal and dependent on magnitude, is used as a basis for discussion for a generic California site. A qualitative discussion between the assumption of independence and dependence between magnitude and site-to-source distance is addressed. Finally, the peak spectral accelerations for the dependent two, three, and four-dimensional cases are compared to one another and the possible consequences associated with increasing the complexity of the environmental contour model analyzed and discussed.     

土动力学与岩土地震工程

近年来,动力荷载引起的工程建设中的新问题给土动力学的研究不断注入新的活力,提出新的挑战,从而推动其发展和完善。文章简要回顾了土工 动力测试技术、土体的动力特性与本构关系、土体液化、土石坝地震响应数值模拟、交通荷载引起的环境振动及长期沉降等方面的研究进展,并对一些需加 强和深入的研究方向进行阐述。     

土动力学与土工抗震研究进展综述

综述当前国内外土动力学与土工抗震方面的研究进展,包括土体动力特性与本构关系、土工地震反应分析、土体动力测试、土体振动液化、土体地震永久变形、交通荷载作用下土体动力特性和土工抗震措施等内容。对各种方法的优缺点进行比较和评述。进一步阐述今后的研究方向。     

A process model for unifying systems engineering and projectmanagement

This article presents an original design for a process model which is considered to be capable of unifying the systems engineering function with project management activities. This design has been developed using an original soft systems methodology which is based on a unique conceptual modelling system for requirements specification. This makes use of a graphical technique for the representation of natural language expressions, known as the systemigram. Systemigrams provide a generic means of enabling systems engineers and project managers to obtain a more enlightened understanding of their problematique     

A collaborative GIS framework to support equipment distribution for civil engineering disaster response operations

After an eXtreme Event (XE) hits an urban area, well-organized response operations are required to mitigate the chaotic situation. Efficient allocation of resources such as construction equipment is critical to the performance of disaster response operations. This paper presents a Geographic Information System (GIS) based framework that facilitates equipment allocation in response to disasters. The framework is composed of three subsystems to facilitate information gathering and decision making for equipment distribution. First, an application that runs on mobile devices for on-field resource request is developed. Second, a resource repository is implemented with a geosaptial database that enables spatial query of resources with a graphical interface. In addition, a GIS which enables automated decision making such as resource matching and route finding for resource distribution is presented. Integration of decision models into the framework to support complex decision making for equipment distribution is also proposed. With the framework in place, disaster response operations could become more efficient. Simulated test cases have been carried out for Champaign, IL, the City of Chicago and the New York City. Future research will be directed towards further expansion and validation of the framework through interaction with emergency management agencies in the US.     

A high-resolution domestic building occupancy model for energy demand simulations

Energy use in the home is a major source of carbon emissions and is highly dependent on the activities of the residents. More specifically, the timing of energy use, particularly electricity, is highly dependent on the timing of the occupants’ activities. Thus, in order to model domestic demand profiles with high temporal resolution, for example, in the context of designing and assessing demand side management systems (including the time-shifting of demand), it is of great benefit to take account of residents’ behaviour in terms of when they are likely to be using household appliances, lighting and heating. This paper presents a thorough and detailed method for generating realistic occupancy data for UK households, based upon surveyed time-use data describing what people do and when. The approach presented generates statistical occupancy time-series data at a ten-minute resolution and takes account of differences between weekdays and weekends. The model also indicates the number of occupants that are active within a house at a given time, which is important for example in order to model the sharing of energy use (shared use of appliances, etc.) The data from the model can be used as input to any domestic energy model that uses occupancy time-series as a base variable, or any other application that requires detailed occupancy data. The model has been implemented in Excel and is available for free download.     

工程抗震设防中的烈度与加速度

烈度与加速度都是描述地震作用下地面震动或影响的标量,但在工程抗震设防中的作用却各不相同。它们类似于佳肴制作中的盐与糖。各种佳肴均离不开盐,但未必需要糖;即便是以糖为主要佐料的甜食,如果稍加一点点盐,则味道会更美好。它们之间可以互为补充,却不能相互代替。本文拟通过相关问题的论述,希望有助于人们科学地看待安评工作中烈度与加速度的结果。     

A model specification for FRP composites for civil engineering structures

A proposed model specification for FRP composite materials for use in civil engineering structural systems is described in this article. The model specification provides a classification systems for FRP materials, describes admissible constituent materials and limits on selected constituent volumes, describes tests for specified mechanical and physical properties, specifies limiting values of selected properties in the as-received condition and in a saturated state, and provides a protocol for predicting long-term property values subjected to accelerated aging based on the Arrhenius model. The model specification is included as an appendix to the article.     

土木工程材料实验的教学改革探讨

分析了传统材料实验存在的不足之处,结合高职教育对技能型、应用型人才的培养,对实验的教学体系、教学内容、教学方法等提出了几点改革建议,以期加强学生的实践动手能力。     

LS-DYNA在工程抗震中的应用

介绍了LS—DYNA软件以及在工程抗震中应用的特点，列举了该软件在高层建筑、地下工程、边坡、土石坝工程抗震分析中的应用以及对人工震源模拟的适用性。     

探究式教学法在工程抗震课程教学中的应用

工程抗震课程是土木工程专业的主干课程。文章结合大量工程抗震案例,按因问设景和因势利导两个步骤进行探究式教学法的实践探索。根据学生的认知结构将其引入场景,并层层推进探寻问题,使学生从观者转变为参与者,并按教学内容进行串联式和并联式场景转换,在互动中强化教师的主导性和学生的主动性,使新型的认知结构同化于心、顺应于物。     

工程管理类专业“四体系一平台”产学研用协同育人模式设计及实现

鼓励企业参与高校育人，深化产教融合，培养适应产业需要的、高素质应用型的人才已成为现代高等教育发展的重要目标。随着新材料、新能源和新技术在工程管理行业的推广与应用，工程管理类专业人才培养需要产教融合。产学研用协同育人作为产教融合的重要方式，存在专业培养方案与课程体系难以满足行业发展需求、校企师资流动差及“双师型”教师缺乏、校企协同中参与各方利益不协调及动力不足、协同育人平台建设滞后及运行机制不健全等问题，急需构建整合行业发展和本科质量标准的课程体系、校企间教师与专业人才流动的师资体系、理论与实践深度融合的“3+1”的培养体系、“全过程+多元化”的监督评价体系与校企相长的协同育人平台，以形成“四体系一平台”的协同育人模式。同时，还需形成校企参与动力机制、协同育人项目实施保障机制、激发各方参与的激励机制和效果评价与反馈机制，以形成“四位一体”产学研用协同平台可持续运营模式。协同育人模式实现，一方面需要政府加大对产学研用支持力度，完善法律、夯实产学研用融合的法律基础，并给予财政补贴和税收减免等方面支持；另一方面需要鼓励工程管理类企业加大高校育人的投入，实施工程管理类产业学院专项发展计划并明确办...     

工程抗震设防工作中的问题及对策

阐述了重大建设工程抗震设防的意义,结合工作实践,就重大建设工程抗震设防工作中存在的一些问题进行了分析,对建设工程抗震设防工作中的对策进行了探讨,以加强和重视建设工程抗震设防工作,促进防震减灾工作的整体发展。     

汶川大地震对工程设计和研究的启示

针对汶川大地震的发生原因和造成的经济损失,结合工程建设和设计方面知识给出在场地选择、抗震设防、鉴定加固、抗震技术和科技投入等几方面的建议,从而为今后工程设计和研究积累经验。     

An evolutionary model for earthquake ground motion

A simple and versatile evolutionary random process model for describing the earthquake ground motion is proposed. The model is composed of individually modulated component stationary processes, each component representing the energy in the process in a narrow band of frequencies. Methods for identifying the model parameters from a recorded accelerogram and for simulating sample functions are described. The model accounts for both temporal and spectral nonstationarity of the motion and is convenient for random vibration analysis.     

A smoke-filling simulation model and its engineering applications

A brief presentation of the computer model DSLAY1, which describes the smoke-filling process in a single enclosure, is first given in this paper. Also some computed data of the model are compared with experimental results to show the agreement between theory and experiment. In the latter part of the paper computed results are presented for areas where the model has been used for different fire engineering applications. The main purpose is to show that zone models like DSLAY1 are useful tools to predict the heat and smoke conditions in single enclosures as a result of growing fires. DSLAY1 is an interactive computer program. The user converses with the program via a terminal connected to the computer. The dialogue is governed by commands adapted to the concepts of the user. Reference: Staffan Bengtson and Bengt Hägglund, A Smoke-Filling Simulation Model and Its Engineering Applications,Fire Technology, Vol. 22, No. 2, May 1986, p. 92.     

Earthquake-induced net section fracture in brace connections — experiments and simulations

Results from six tests, finite element simulations and a synthesis of previous test programs on slotted end bracing connections are presented. The main objective of the research is to examine the deformation capacity of these connections, with the ultimate objective of minimizing the requirement for net section reinforcement that is often inconvenient from the perspective of fabrication. The experiments and simulations feature commonly used pipe specimens and end details. The main parameters investigated include the gusset plate thickness, the slot length and introduction of a wrap-around weld that eliminates the reduced section at the edge of the gusset plate. The results indicate that even without reinforcement, the connections offer adequate to excellent deformation capacity if they are provided with the wrap-around weld or if the net section strength is larger than the gross yield strength. This may be achieved in situations where shear lag in the connection is minimal, and where the area reduction due to the slot is small relative to the gross area. Design considerations are presented along with limitations of the study.