Revista de Engenharia Civil e Ambiental

Health concerns have been raised, especially following the enormous increase in the use of wireless mobile telephony (GSM, 3G and 4G) throughout the world. A similar situation exists regarding other digital wireless systems, such as data communication networks, Bluetooth, Wi-Fi, DECT phones and CB’s which emit in various regions of the spectrum giving rise to cumulative radiation exposure. These concerns have induced a large body of research as mobile devices use electromagnetic waves in the microwave range. In the present work, we have measured the EMF of various emitting devices at different frequencies as well as the contribution of wireless emitting ones in various areas of special interest such as Universities, hospitals, airports. The peaking measurement was at the entrance of the airport (300 mV/m) and the minimum (7 mV/m) in a “neutral University location” with the least human accumulation in comparison with the other studied places. The other studied emitting devices showed a logarithmic decrease, which is significant up to 50 cm away from the base station.

We compared the prevalence of hypertension in subjects that lived on main roads with those that lived in side streets. An odds ratio of 1.310 (95% CI = 1.052-1.631) was found for those who lived on the main roads. In this traffic-exposed subgroup, subjects that had the living and the bedroom facing the road an odds ratio of 1.736 (CI = 0.673-1.882) was found in comparison with those who had both rooms on the rear side of the house. In subjects that lived on side streets the location of the rooms was meaningless (OR = 1.102, CI = 0.648-1.874).

This research explored the possible modification of precipitation around large reservoirs in the Cascade Range and Sierra Nevada Mountains in the Western US where orographic precipitation is dominant. After investigating the hypothesis that an additional and man-made source of moisture, such as an artificial reservoir and irrigated landscapes, can modify pre-dam state of orographic process on the windward side or the convective process on leeward side of the mountain, the result is interpreted in terms of better water resources management for future reservoirs. Mann-Kendall’s trend analysis and Sen’s slope estimator were applied for testing the hypothesis using historical hydrometeorological observations (precipitation, relative humidity- RH, and dew point temperature-DPTP). Four blocks of reservoirs (two from Cascade Range and two from Sierra Nevada) and six individual reservoirs were considered in this analysis. Comparison of post-dam period results for the selected reservoirs showed that atmospheric moisture content on the leeward side has a higher slope of increase than windward side. On the other hand, extreme precipitation (90th percentile and above) was found to have an increasing trend for both windward and leeward side during the post-dam era. A key conclusion of this site specific research article is that there is an indication reservoirs in drier location (leeward side) seem to increase precipitation more than those on the windward side. This means we can make use of this extra quantity of flow volume in post-dam period for a sustainable water resource management. Such approach can be part of climate change mitigation and resilient approach to extreme events. As large reservoirs are big parts of socioeconomic development specially in economically emerging countries around the globe, new approach into dam design and operation is important. This means identifying any impact of reservoirs and land use land cover change then leverage this impact as an advantage rather than otherwise.

The passage way of road vehicles, humans and domestic animals over rails is called “crossing” at railways. The most significant of crossing are roadway crossings and level crossings have particular importance among them. Railway level crossings safety influences on rail and road transportation safety. 10% of rail accidents occur on crossings and 10% of crossing accidents cause to death. This issue indicates the importance of crossing safety. Several factors is effective in crossing safety. For example, rail and road vehicles should be aware of approaching the crossing at a proper distance and have appropriate visibility to each other for safe passage through crossings. So line and road sight obstacles should be eliminated at specified distance. In this paper, we try to determine proper dimensions of unobstructed area for maximum speed 120 km/hr of passenger trains and maximum road speed limit 120 km/hr of Iran railway lines by examining previous studies in other countries, Iran railway regulations and international standards. Railway track and road should not have horizontal or vertical arc at this distance and to provide enough visibility, any obstacles including trees, buildings, fixed or mobile equipments and etc. should not exist in distances forming triangle. Also the effects should be considered if there is any slope in both sides of crossing at railway track, road or any speeds change in calculations.

In this paper, based on MacLaurin’s series and the Riccati equation, an algebraic quadratic equation will be developed and hence, its two roots, which represent the minimizing and maximizing optimal control matrices, would be deducted easier. Otherwise, a step-by-step algorithm to compute the control matrix for every step of time according to the preceding responses and a new signal pick will be explained. The proposed method presents a new discrete-time solution for the problem of optimal control in the linear or nonlinear cases of systems subjected to arbitrary signals. As an example, a system (structure) of three degrees of freedom, subjected to a strong earthquake is analyzed. The versus time displacements and the stiffness forces versus displacements of the system, for the two uncontrolled and controlled cases are graphically shown and clarify the great reduction of the controlled system results, in comparison with the uncontrolled system ones. The curves of variations of the elements of the optimal control matrix versus discrete-time are also presented.

This research is devoted on the study of creep behavior of asphalt binder in hot region. This binder was subjected to thermal cycles due to the variation of temperature from day to night. These cycles produce a heating-cooling phenomenon. To evaluate the effect of climate change in laboratory, it was used the rheometer DSR, and compare the results found with the nine sample. These thermal cycles led to aging and therefore hardening of the binder. Thus, the proposal of a rheological model that can represent the curves obtained experimentally, where it is able to describe the creep behavior of binders tested. It is proposed a new model that correlates well with the experimental curves, it is called A+2K.

Solid waste management is being done in several ways but there is a need for an effective and a creative way that aims to bring sustainable development in the construction industry. Existing methods of waste management and disposal like the land filling is ultimately polluting the soil and ground water. The need for manufactured aggregates is to promote the 3 R’s (Reduce, Reuse & Recycle) and to achieve a sustainable development. Manufactured aggregates may reduce environmental strain by minimizing over exploitation and indiscriminative use of natural aggregates which we get from the mining, quarrying and blasting activities. Waste is not a waste unless you waste it. This paper focuses on the synthesis of an ingenious construction material (Coarse aggregates) from the various industrial wastes which are ceramic materials, lathe waste and plastics (Low density & Medium density polyethylene) along with slag (fly ash/ Ground Granulated Blast furnace Slag) in definite proportions. Coarse aggregate synthesised through this process have both advantages and disadvantages when compared to the natural aggregates. Various tests for aggregate which are specified in the IS 2386 does not seem applicable as these artificial aggregates undergo elastic or plastic deformation.

This paper reports the effect of concrete using copper slag as fine aggregate replacement. In this project work, the concrete grade M40 was selected and IS method was used for mix design. The properties of material for cement, fine aggregate, coarse aggregate and copper slag were studied for mix design. The various strength of concrete like compressive, flexural and split tensile were studied and non-destructive test such as rebound hammer test and ultrasonic pulse velocity measurement were studied for various replacements of fine aggregate using copper slag that are 0%, 20%, 40%, 60%, 80% and 100%. The maximum compressive strength of concrete attained at 40% replacement of fine aggregate at 7 and 28 days. The split tensile strength and the flexural strength were also obtained higher strength at 40% replacement level at 28 days. The rebound hammer test showed higher compressive strength at 40% fine aggregate replacement, this is due to uniformity of concrete. The pulse wave velocity is higher for the 40% fine aggregate replacement, it is understood that the density of the mix is high and free from pores.

Air pollution mapping is now being an important issue to manage and enhance the environment of a city. The major problems of air pollution mapping is the data acquisition due to the high cost of instruments and the high spatial distribution requirements. This study aimed to monitor Sulfur Dioxide over Kirkuk city using Landsat-8 thermal bands to provide Department of Environment Kirkuk with low-cost Sulfur Dioxide concentration maps to better manage the city. The study used correlation analysis to find a relationship between Sulfur Dioxide ground-based measurements and satellite data. The ground-based measurements were collected from (17) stations distributed in Kirkuk city in January, 2014 using NOVA device to measure SO2 concentrations. The research showed a good correlation between groundbased measurements and satellite data with (R2=0.48 for band 11 and R2= 0.52 for band 10). Therefore, the study resulted that with band 10 of Landsat-8 data, better SO2 can be monitored than using band 11. It is recommended to other researchers to investigate the ability of free remote sensing data to monitor all elements that specify the air quality of a city.