To Integrate of Not to Integrate?

Turkish architecture over the last 150 years has been plagued by its preoccupation with its integration with the West. Should it be embracing or reflecting Western cultural, technical and professional standards? Uğur Tanyeli provides the background to this pessimistic context and describes how a new generation of architects over the last 10 years have transcended this predicament by producing work that turns away from this obsession with identity. Copyright © 2010 John Wiley & Sons, Ltd.     

Simulations of explosion-induced damage to underground rock chambers

A numerical approach is presented to study the explosion-induced pressure load on an underground rock chamber wall and its resultant damage to the rock chamber.Numerical simulations are carried out by using a modified version of the commercial software AUTODYN.Three different criteria,i.e.a peak particle velocity (PPV) criterion,an effective strain (ES) criterion,and a damage criterion,are employed to examine the explosion-induced damaged zones of the underground rock chamber.The results show that the charg...     

Response of steel beam–columns exposed to fire

Steel beams when exposed to fire develop significant restraint forces and often behave as beam–columns. The response of such restrained steel beams under fire depends on many factors including fire scenario, load level, degree of restraint at the supports, and high-temperature properties of steel. A set of numerical studies, using finite element computer program ANSYS, is carried out to study the fire response of steel beam–columns under realistic fire, load and restraint scenarios. The finite element model is validated against experimental data, and the importance of high-temperature creep on the fire response of steel beam–columns is illustrated. The validated model is used to carry out a set of parametric studies. Results from the parametric studies indicate that fire scenario, load level, degree of end-restraint and high-temperature creep have significant influence on the behavior of beams under fire conditions. The type of fire scenario plays a critical role in determining the fire response of the laterally-unrestrained steel beam within a space subframe. Increased load level leads to higher catenary forces resulting in lower fire resistance. Rotational restraint enhances the fire resistance of a laterally-unrestrained steel beam, while the axial restraint has detrimental effect on fire resistance.     

Imperative to Fulfill Full Priority Development of Public Transport

In the bluebook regarding public transport policies of our country,various documents and specialized papers ontraffic management,great emphasis has been laid on giving priority to the development of public transport.However,the problem of difficult bus-riding has become increasingly serious.What efforts have we made to facilitate the prior-ity development of public traffic in our urban planning,urban construction,and traffic management? What preferen-tial policies have been adopted for that purpose? The author attempts to discuss how,on the competitive market ofpassenger transport,public transport can make greater contribution to urban development.     

Strive to Raise the Level of China''''s City Planning and Design to Suit the Needs of Development in the New Historical Stage

ⅠKeeping step with the economic re-structuring and the policy of opening tothe outside world,marked progress hasbeen made in China's urban constructionand great strides have been taken in cityplanning during the ten years and more re-cently.This is manifested in the following5 respects.A.Thanks to the implemen-tation     

Luozhuang A Road to Urbanization of the Countryside in China

In China it is common knowledge thaithe development of cities is arranged inaccordance with the plan of the nationaleconomy.Since the implementation of theFirst Five-Year Plan in 1953,cities orientedto modern industries have emerged in manyof the former economically backward areas,such as Lanzhou in Gansu Province,whichis mainly known for its petrochemical indus-     

A Review of “How to House the Homeless”

Gender is both an archetypal and adaptive dimension of the urban condition and, thus, remains a key moving target for planning practitioners and scholars alike. This is especially true of women's growing, if not revolutionary, involvement in the economy. A familiar exception is the trip linking work and home, which has been consistently and persistently shorter for women than men. That said, new reports suggest that the gender gap in commuting time and distance may have quietly vanished in some areas. To explore this possibility, I use panel data from the American Housing Survey to better measure and explain commute trends for the entire United States from 1985 through 2005. They overwhelmingly indicate that differences stubbornly endure, with men's and women's commuting distances converging only slowly and commuting times diverging. My results also show that commuting times are converging for all races, especially for women, and women's trips to work by transit are dwindling rapidly. Thus sex continues to play an important role explaining travel, housing, and labor market dynamics, with major implications for planning practice.     

Engineering Variables to Replace the Concept of ‘Noncombustibility’

The concept of noncombustibility evolved in the early days of building codes, before quantitative methods of measuring and assessing components of fire hazard were available. ‘Noncombustible’ lacks a technical definition of general scope, but in the US codes, which are the primary focus of this study, it is defined as a material which meets the criteria of the ASTM E136 test. The hazard variables underlying the noncombustibility concept are examined in this study. In view of today’s state of the art, it is shown that noncombustibility requirements, in most cases, constitute a misapplication of fire safety principles and that their use should be discontinued, in preference of using variables that express quantitative fire safety principles. Heat release rate (HRR) is the primary variable which correctly establishes the relevant hazard. In recent years, some regulations have been promulgated which use bench-scale HRR test results directly for this purpose. The ultimate hazard to be addressed, however, is the full-scale HRR behavior. When the hazard involves fires which may spread over surface linings, however, the full-scale HRR is not simply directly scaled to the bench-scale HRR. To quantify this hazard properly, additional properties of the material which govern the flame spread behavior need to be considered. A simple, easy-to-use method for this purpose are described, which is based solely on data obtainable from the Cone Calorimeter (ASTM E1354; ISO 5660) test. Validation of the concept against room-scale data is provided and is shown to be successful.     

Decay of sandstone subjected to a combined action of repeated freezing–thawing and salt crystallization

Bulletin of Engineering Geology and the Environment - The weathering of rocks controls the shape of the Earth’s surface and affects their suitability as building stones. Frost weathering and...     

Improving Planning Mechanism to Upgrade the Planning Level of Old Cities

Before 1980,in the development ofChina's cities,emphysis was laid on theconstruction of new cities and expansionof new urban districts.As for old citiesand old urban districts,the principle of“full utilization and gradual transforma-tion”was adopted.Therefore,accordingto general comprehension,old cities main-ly refer to the areas which were formed inhistory and need to be maintained andtransformed now,and they usually in-clude inner city and areas built before     

Is it possible to estimate atmospheric deposition of heavy metals by analysis of terrestrial mosses?

Here we present a critical review of diverse research studies involving estimation of atmospheric deposition of heavy metals from the concentrations of the contaminants in terrestrial moss. The findings can be summarized as follows: i) significant correlations between the concentrations of contaminants in moss and bulk deposition were observed in only 40.1% of the cases in which the relationship was studied and in only 14.1% of the cases, the coefficient of correlation was > 0.7; ii) some method-related problems were identified (i.e. small sample sizes, elimination of some data from the regression analyses, large distances between the moss sampling sites and the bulk precipitation collectors, differences in times of exposure of the moss samples and collection times for the bulk precipitation), so that the results of the studies may not be completely valid, and iii) evidence was found in the relevant literature that moss does not actually integrate the atmospheric deposition received. We also discuss the reason why, in accordance with the published data, bulk deposition cannot be correctly estimated by determination of the final concentrations of contaminants in the organism, such as the existence of different sources of contamination, the physicochemical characteristics of the sources of deposition, physicochemical processes to which the organism is subjected and the biological processes that take place in the moss. Taking into account the above findings, it was concluded that, except for certain elements and specific cases (i.e. Pb and Cd), atmospheric deposition of elements cannot be accurately estimated from the concentrations of metals and metalloids in moss tissues. However, the analysis of moss does provide information about the presence of contaminants in the atmosphere, their spatial and temporal patterns of distribution and how they are taken up by live organisms. Use of mosses is therefore recommended as a complementary (rather than an alternative) technique in the conventional analysis of bulk deposition of contaminants.     

Is low-level environmental mercury exposure of concern to human health?

Mercury has long been recognised as toxic, principally in relation to its effects on humans following acute or prolonged high-level occupational exposures and, in the latter half of the last century, from a number of environmental incidents. Recognised target organs are the kidneys, central nervous system and thyroid glands. Recently concern has grown about the potential risks to the human population from current background environmental levels, leading bodies such as the World Health Organisation to call for the reduction or, wherever possible, elimination of the use of mercury. This review considers the strength of the epidemiological evidence on the effects of prolonged low-level exposure to the various forms of mercury.The limited research base suggests that several of the potential targets of long-term environmental exposure to mercury are similar to those occurring from occupational exposure including the renal, cardiovascular and immune systems. However, the evidence also suggests that, particularly in the case of organic mercury compounds, the most sensitive endpoint is central nervous system toxicity, especially in relation to exposure during the in utero period and childhood. It also appears that those human populations which have traditionally consumed diets high in seafoods are at greatest risk. While the extent of risk to the general population that may arise from existing environmental exposure levels appears limited, this conclusion is based on an incomplete dataset and therefore the general consensus view that exposure to mercury in its various forms should be minimised where practical, appears to be justified. A number of potential areas of further research are suggested as being pre-requisite to the development of a more rigorous risk assessment.     

Preliminary engineering application of microseismic monitoring technique to rockburst prediction in tunneling of Jinping Ⅱ project

Monitoring and prediction of rockburst remain to be worldwide challenges in geotechnical engineering.In hydropower,transportation and other engineering fields in China,more deep,long and large tunnels have been under construction in recent years and underground caverns are more evidently featured by ＂long,large,deep and in group＂,which bring in many problems associated with rock mechanics problems at great depth,especially rockburst.Rockbursts lead to damages to not only underground structures and equipments but also personnel safety.It has been a major technical bottleneck in future deep underground engineering in China.In this paper,compared with earthquake prediction,the feasibility in principle of monitoring and prediction of rockbursts is discussed,considering the source zones,development cycle and scale.The authors think the feasibility of rockburst prediction can be understood in three aspects：（1） the heterogeneity of rock is the main reason for the existence of rockburst precursors;（2） deformation localization is the intrinsic cause of rockburst;and（3） the interaction between target rock mass and its surrounding rock mass is the external cause of rockburst.As an engineering practice,the application of microseismic monitoring techniques during tunnel construction of Jinping II Hydropower Station was reported.It is found that precursory microcracking exists prior to most rockbursts,which could be captured by the microseismic monitoring system.The stress concentration is evident near structural discontinuities（such as faults or joints）,which shall be the focus of rockburst monitoring.It is concluded that,by integrating the microseismic monitoring and the rock failure process simulation,the feasibility of rockburst prediction is expected to be enhanced.     

Determination of the Scale of Damage in the Wastewater Tunnels Due to Earthquake： A Case Study

The pre-determination of the effect of earthquake in subsurface structures is gaining importance increasingly. One of the main factors in determination of the damages due to earthquakes in subsurface structures, especially tunnels are horizontal acceleration value. The aim of the study is to put forward the scale of damage due to earthquake in a wastewater tunnel in Istanbul, the most populated city of Turkey, under construction. Possible damage caused by earthquake will be determined by utilizing the information about the route of the wastewater tunnel analyzed in the study.     

From Architecture to City——On architects'''' awareness of urban environment

This article puts forward four aspects for moving to-wards the city:Moving towards compositional frame—respect,ad-just,safeguard and create cities and group structures:moving to-wards the future—this requires“looking back”and“looking for-ward.”to form diversified and harmonious groups;moving to-wards the engineering svstem—becoming an organic componentpart of city road traffic,topographical readjustment,preventing andfighting natural disaster systematic projects;moving to the soft envi-ronment—satisfying the demands of urban economic and social de-velopment,history and culture,and customs and habits.     

Condition assessment of building façades based on hazard to people

Abstract

To make periodic inspections of the buildings is useful to quantify the extent to which deficiencies are severe or not, in order to facilitate decision making and prioritize interventions. In previous works by the authors is proposed a scale of gravity of damages in buildings, with the aim of being of widespread and of common use among professionals. This scale is applied through the direct assignment (DA) methodology, based on the generic definitions of each degree. It is demonstrated and characterized the existence of certain level of variability among technicians, when assigning gravity values using DA methodology, due to the fuzzy condition of the attribute to be evaluated. The main goal of this paper is to propose a methodology to assign values of gravity, based on hazard for people of detachments from the façade, by using measurable parameters and mathematical functions. The final objective is to reduce the level of variability among inspectors when assessing the condition state of a building façade. The proposed methodology is named system of evaluation of façades (SEF). The methodology can be also extended to the assessment of other building systems as structures or roofs and other type of infrastructures.