不容忽视的建筑物等电位联结

对总等电位联结、局部等电位联结、辅助等电位联结等几种建筑物等电位联结的具体做法进行了介绍,并详细阐述了等电位联结的作用,以防止因建筑物内出现电位差而导致事故的发生,消除安全隐患。     

浴室内局部等电位端子板联结做法的探讨

等电位联结技术是工程中一项重要的安全技术措施,它的应用与否直接影响到人们的生命安全。国家建筑标准设计图集《等电位联结安装》（02D501-2）和建筑电气通用图集《建筑物防雷装置》（09BD13）对浴室内局部等电位端子板联结的方法做出了不同的规定,笔者针对两种不同的方法进行了分析及探讨,以求等电位联结技术在工程中得以深入的应用。     

浅谈建筑等电位联结的几个问题

阐述了建筑物等电位联结的相关概念,重点介绍了卫生问的等电位联结,论述了建筑物等电位联结的有效性,总结了建筑物等电位联结实施过程中应注意的几个问题,指出建筑电气设计中采用等电位联结是防电击、雷击的一种行之有效的安全措施.     

关于住宅楼等电位联接施工探讨

住宅楼的安全用电是关系到千家万户的大事,采用总等电位联结和局部等电位联结是很重要的措施。IEC标准把等电位联结作为电气装置最基本的保护,我国有关电气装置设计规范已将建筑物内作等电位联结规定为强制性的电气安全措施。本文参照就建设部发布的新的《等电位联结安装》标准设计图集,详尽介绍了设计、施工的具体方法、质量检验标准。     

浅谈等电位联结安装

随着近年建筑电气日益发展,安全用电越来越重要。采用接地故障保护时,在建筑物内作总等电位联结已经列入强制性条文。本文就等电位联结安装浅谈个人的一些体会。     

总等电位联结和辅助等电位联结的重要性

强调了电气设计中总等电位联结和辅助等电位联结的重要性,列出了建筑物的总等电位联结图,对只需做总等电位联结的情况和宜采用局部辅助等电位联结的情况进行了探讨,最后对等电位联结及其联结线进行了研究,以降低雷击和电位差对建筑物造成的损失。     

浅谈等电位联结安装

随着近年建筑电气日益发展,安全用电越来越重要.采用接地故障保护时,在建筑物内作总等电位联结已经列入强制性条文.本文就等电位联结安装浅谈个人的一些体会.     

论建筑物的等电位联结

介绍了建筑物的等电位联结方法，从总等电位联结、局部等电位联结、辅助等电位联结等方面进行了论述，阐述了等电位联结的作用，提出了等电位联结的必要性。     

医疗建筑等电位设计综述

辅助等电位联结与局部等电位联结概念容易混淆,介绍等电位联结概念和分类。从设计师角度出发,探讨医疗建筑中总等电位联结、局部等电位联结、辅助等电位联结的具体设计做法。     

浅谈对民用建筑等电位联结的认识

针对接地故障的危险性,介绍了等电位联结的定义及分类,在此基础上,联系国家建筑标准设计图集《等电位联结安装》,具体阐述了建筑物的等电位联结做法,指出等电位联结可以有效防止由接地故障引起的电位差。     

Critical Factors in Financing and Management of Light Rail Transit Systems： Delphi Methodology Approach

In recent years, a large number of LRT （light rail transit） networks and tramways have been built in Spain using the tender system. The rhythm of construction has been such that very few analyses have been carried out and those that have were only partially done because the main participants involved had ulterior motives which impeded their having a critical and independent opinion of the projects carried out. Within this framework, the Delphi methodology presents itself as a very useful instrument, as the intrinsic advantages that it has added to the characteristic that the experts who participate in the project can remain anonymous without detracting value from the conclusions obtained as these are grouped together according to their worth.     

Unanticipated Bond Failure over Supporting Band Beams in Grouted Post-Tensioned Slab Tendons with Little or No Initial Prestress

After grouting the ducts in a large band beam and one-way slab post-tensioned floor system in a large shopping mall （in excess of 1.5 km2 in plan）, doubts arose concerning the level of initial prestress and the strength and serviceability of the slabs was questioned. To assess the strength of the slabs, it was assumed, as a worst case scenario, that some spans may have been constructed with zero initial prestress. Load tests on prototype specimens, with similar dimensions and reinforcement quantities as the floor slabs, were performed to assess the stress development in initially unstressed, but fully grouted, tendons. Unexpected bond failures occurred at the junctions of slab and band beam where the abrupt change in section depth caused a sudden change in tendon stress. The maximum stress that was developed in the initially unstressed tendons at these locations was about 60% of the strength of the tendons.     

Flexible Pavement Design Simulation Using Mechanistic-Empirical Pavement Design Guide

The KDOT （Kansas Department of Transportation） is currently adopting MEPDG （mechanistic-empirical pavement design guide） to replace the 1993 AASHTO （American Association of State Highway and Transportation Officials） design method. The main objective of this study was to compare flexible pavement design using 1993 AASHTO design guide and MEPDG. Five newly built Superior PERforming Asphalt PAVEments （Superpave）, designed using the 1993 AASHTO Design Guide, were selected as test sections for the design simulation study. Deflection data were collected approximately 8 to 10 weeks after construction using FWD （falling weight deflectometer）. The FWD deflection data were used to back-calculate the pavement layer moduli using three different back-calculation programs. The existing pavement structures were analyzed for a 10-year analysis period. The maximum numbers of years the existing pavement structures will be in a serviceable condition as well as the minimum thicknesses of different layers to serve for 10-years were also determined. Effects of changing subgrade modulus, target distress, and reliability were also investigated. The MEPDG design analysis shows that the 1993 AASHTO Guide-designed flexible pavements do not show the distresses currently observed in Kansas for the 10-year design period. The MEPDG design simulation shows that the thinner the pavement sections, the higher the permanent deformation. The existing pavement structures can serve for more than 20 years as per the MEPDG design analysis if the default failure criteria and nationally-calibrated models are used.     

Infilled Reinforced Concrete Beams for Sustainable Construction

This paper presents a study carried out on infilled reinforced concrete beams for sustainable construction. In reinforced concrete beams, less stressed concrete below neutral axis can be replaced by some light weight material to reduce the weight of the structure and also achieve the economy. The used infilled material is brick. Sustainability can be achieved by replacing the partially used concrete. By saving concrete, the authors save cement, which reduces the green house gases emissions. So it is considered as environment friendly. Since infilled beam acts like a layered member, there needs a theory to analyze it. Method of initial functions is used for the analysis of the infilled RC （reinforced concrete） beams. This method is successfully applied on infilled beam. Results show that physical conditions are verified for infilled beam.     

Economy of RHA （Rice Husk Ash） in Concrete for Low-Cost Housing Delivery in Nigeria

Delivery of housing units in adequate quantity and quality has been the pursuits of individuals and successive governments in Nigeria. Still, the gap between demand and supply is becoming wider on daily basis due to exorbitant cost of building materials that is beyond the reach of average Nigerians. Concrete being the most acceptable construction material is expensive due to high cost of cement. Efforts made to reduce the cost of cement were to no avail, thus there is need to look elsewhere. Past researches showed that substituting cement with 15% of RHA （rice husk ash） in concrete improves the performance of concrete and reduces global warming as a result of emissions from cement production. This paper looks into the effect of using RHA as partial substitute of cement on the cost of a low-cost housing unit. Results showed that cement based construction materials are responsible for 82.58% of the total cost in which cement is responsible for 42%. When 15% RHA was used to substitute cement over N90,000 was saved, amounting to about 7% of the total cost of the building. In addition, depletion of natural resources was reduced.     

Bending Stresses of Steel Web Tapered Tee Section Cantilevers

Although commonly used, no design method is available for steel web tapered tee section cantilevers. This paper investigates the bending stresses of such beams. Relationships between the maximum compressive stress and the degree of taper were investigated. An analytical model is presented to determine the location of the maximum stress when subjected to a uniformly distributed load or a point load at the free end and was validated using finite element analysis and physical tests. It was found that the maximum stress always occurs at the support when subjected to a uniformly distributed load. When subjected to a point load at the free end and the degree of taper is up to seven, it was found that Miller＇s equation could be used to determine the location of the maximum stress. However, it is shown that when the degree of taper is greater than seven, Miller＇s equation does not accurately predict the location and the analytical model should be used. It was also found that the location of the maximum stress was solely dependent on the degree of taper, while a geometric ratio, fl was required to determine the magnitude of the maximum stress. A simple method that predicts the magnitude of the maximum stress is proposed. The average error in the prediction of the magnitude of the maximum stress is found to be less than 1.0%.     

Probabilistic Seismic Hazard Assessment for Bridgetown-Barbados,Employing Subduction Interface Characteristic Earthquakes

A new probabilistic seismic hazard analysis was performed for the city of Bridgetown, Barbados, West Indies. Hazard computations have been performed using the standard Cornell-McGuire approach based on the definition of appropriate seismogenic sources and expected maximum magnitudes, the authors take into consideration the possibility of large subduction interface earthquakes of magnitude 8.0-9.0 beneath the Barbados accretionary prism via application of a characteristic model and slip rates. The analysis has been conducted using a standard logic-tree approach. Uniform hazard spectra have been calculated for the 5% of critical damping and the horizontal component of ground motion for rock site conditions setting 5 return periods （95, 475, 975, 2,475 and 4,975 years） and spectral accelerations for 34 structural periods ranging from 0 to 3 s. The disaggregation results suggest that the magnitude-distance pair that dominates the hazard yields M 7.4 and 8.6 and a distance of 42.5 km in the Interface Subduction Zone beneath Barbados for the 475 and 975 years RP （return period）, respectively. An event with an M 8.0 at a distance of 107.5 km in the Intraplate Subduction Zone is the second scenario that dominates the hazard for both 475 and 975 years RP.     

Use of Geophysical Techniques for the Localization of the Restricting Zones of Permeability in the Bottom of Basin： Forecasting the Zones of Clogging

Measurements of dielectric parameters followed by permeability tests are performed on soil samples of infiltration basin. The dielectric parameters are obtained by TDR （time domain reflectrometry） measurements from which it is found that the measurement of the permittivity, the electrical conductivity and the relaxation time of compacted soil allows the mapping of the values of the coefficient of permeability at the surface of an infiltration basin. With the distribution of the coefficient of permeability, the areas of water stagnation can be detected before the basin filling. The study proves that the TDR measurements for the detection of these zones can be used for the management of infiltration basins for sustainable working and their remediation can be undertaken before the rainy seasons.     

Sustainable Methods and Techniques in Old and New Public Constructions

This article is about the methods and techniques used in the building ＂retrofit＂ in modernist style designed by the architect Affonso Eduardo Reidy in the fifties, and also about the project of the new Rio de Janeiro MIS （Museum of Image and Sound）, under construction, by The North-American office Diller Scofidio ＋ Renfro, both located in the city of Rio de Janeiro. These constructions present a wide view of the concept of sustainability, not commonly used in public buildings in Brazil. In the building designed by Reidy, which belongs to the State of Rio de Janeiro, the regeneration to host the new headquarters of the State Department of Taxation and Finance respected its original characteristics and used smart and sustainable design techniques, as well as recyclable materials. On the other hand, the project of the new museum at Copacabana Beach was entirely planned on sustainable bases and it includes the application of building techniques concerning that purpose. This article presents a study of these two cases and evaluates the techniques and materials used in one another. Observing the principles of sustainability in construction is a pioneering initiative of the State Government. This article aims at making the scientific community aware of the needs of immediate adoption of sustainability techniques in Civil Engineering, not only in the construction of new buildings, but also in the regeneration of the existing ones, as well as the need of imperious adoption of sustainable techniques when it comes to maintainability.     

Social Participation in the Context of the Urban Public Space Renewal： The Case of Lagarteiro Neighborhood in Oporto

In 1980, Giancarlo de Carlo wrote in the Perspecta： Yale Journal, ＂An Architecture of the Participation＂. Carlo, proposed a sequence of procedures： the problem definition, the solution and the results evaluation, in all the three steps, the social communities should be integrated in as part of a share and dynamic process. This text corresponds to a new way of understanding the importance of the social communities in the architecture definition. From de Carlo＇s text, the main goal of this paper is to present the results of an intervention in public space renewal of the Lagarteiro neighborhood （in Oporto city） and the relation of this process with the participation of the resident population. The urban context of Lagarteiro＇s neighborhood presented before the intervention the typical and classic signs of disqualification of environmental and urban peripheral areas of resettlement. The term ＂disadvantaged areas＂ is associated with these areas in urban or peri-urban case, was framed in a specific Portuguese policy, called Initiative Critical Neighborhoods. Being a recent intervention, the renewal of the public space in Lagarteiro is a complete case study that allows comprehending the participation phenomenon in nowadays, at the same time that seduces a reflexion about technical and architectural solutions for ＂critical＂ neighborhood.