Civil Eng

The rainfall Intensity-Duration-Frequency (IDF) relationship is one of the most commonly used tools in water resources engineering, either for planning, designing and operating of water resource projects. The purpose of this research is to get curves frequency the intensity of rain duration for Nasiriyah city, Iraq, and finding empirical equations the curves. Where are collected data of the rain 36 years ago from 1980 to 2015. Used Indian Meteorological Department (IMD) empirical reduction formula and methods of distribution: Gumbel and Log Pearson Type III during short periods (10, 20, 30, 60,120,180, 360, 720 and1440) minute with a specified return period (2, 5, 10, 25, 50 and 100) years. The results obtained showed that intensity of rainfall decreases with increase in storm duration and rainfall of any given duration will have a larger intensity if its return period is large. The chi-square goodness of fit test was used to determine the best fit methods of distribution (Easy fit software 5.6) and conclude that the Log Pearson type III was the best method.

Existen diversas cargas que actúan dinámicamente sobre las estructuras cargas de sismo, viento, de impacto, etc. Los daños que producen deterioro y hasta el colapso de las estructuras son producidos por los desplazamientos relativos de la estructura transductores utilizados actualmente para realizar las mediciones de las vibraciones de las estructuras son los acelerómetros, que mediante la doble integración de la aceleración se determinan los desplazamientos, y los LVDT que determinan la posición conjunto de bobinas. Este trabajo presenta una para determinar la respuesta de una estructura mediante un dispositivo que permite la medición de desplazamientos en modelos y/o varios grados de libertad en forma directa, cuando estos modelos físicos se ven sometidos a acciones dinámicas.

Three data-driven modelling techniques (Artificial Neural Networks (ANN), Adaptive Neuro Fuzzy Inference Systems (ANFIS), and Autoregressive Integrated Moving Average (ARIMA)) were used for predicting of Euphrates River flow for one month ahead in Thi Qar City at Southeastern Iraq. The monthly average discharges of Euphrates River for the period (1995-2015) were used in this research. Three layers feed- forward network with sigmoid hidden neurons and linear output neurons are used in this research, the ANN is trained with Levenberg-Marquradt back-propagation algorithm. The total number of observations data was equal to 248 samples; divided into three statistical groups (148 samples as a training group, 50 samples as a validation group, and 50 samples as a testing group). Two preceding discharge values (Qt-1, Qt-2) were used for predicting the discharge value (Qt). The clustering radius is an important parameter to determine the number of clusters and fuzzy if-then rules in ANFIS model. The best value of clustering radius (0.8) was associated with lowest value of checking root mean squared error (33.716).According to statistical evaluation criteria, ANFIS model was better than ARIMA model, and slightly better than ANN model. The superiority of the ANFIS technique to the ANN and ARIMA models due to the fuzzy clustering of the input space and for creating a rule-base to generate the output. ANFIS model can be used by the Iraqi Ministry of Water Resources to extract results close to reality and give an approximate estimate of the expected flow values in the Euphrates River, better than using other high-cost models such as conceptual models or physically based models.

A leading, international, engineering and construction company has carried out efforts to engage a new tool set and work process. Four-Dimensional Planning and Scheduling (4D-PS) is the new work process that aims toward better, more efficient planning and execution of large construction projects. This paper describes the case history and forecasts how this revitalized technique may ultimately impact the
construction industry. Despite academic and practitioners’ research and
development efforts to leverage from Information Technology (IT) in construction, the industry at large, being generally conservative, has adhered to the values of predictability and existing methods to minimize risk. 4D technology has struggled to find its way into mainstream construction practice for several years, and just
recently it has been shown that commercially available software and hardware can be applied effectively toward this end, greatly reducing investment risk. These relatively new tools promise new impetus to the use of 4D-PS in the construction industry. This paper describes how 4D-PS was applied on a major construction project, giving rise to a new work process that proved to be productive and cost effective. Emphasis is made on the fact that those expected to use such technology
must have the necessary training and, conversely, near-future versions of computerized tools can be made more intuitive for more widespread use. The use of such techniques will necessarily draw engineering/design and construction entities closer together, essentially improving coordination among them.

This paper presents some results of the application of research thinking within
an industrial project environment. During the last five years the impact of Computer
Advanced Visualization Tools (CAVT) in the design and construction process of industrial
projects was studied as part of a research carried out by the Universidad Católica de Chile and
Bechtel Chile Ltda. A Ph.D. researcher working within Bechtel developed methods and
procedures to conduct 4D Planning and Scheduling (4D-PS). His work included pioneering
the first 4D application on a large project that rendered significant and demonstrable savings
in man-hours and materials, showing that 4D technology is viable and cost-effective. Benefits
of applying CAVT to the design process, new conceptualization of the design process, review
of the constructability concept and guidelines to manage organizational change due to IT
impact are examples of the research results that will be presented and discussed in this paper.

In the determination of statistical parameters of reinforcement steel conducted in this study, necessary parameters (i.e. steel diameter, area, yield strength, ultimate strength, and elongation) needed were obtained from the department of Civil Engineering, Ahmadu Bello University Zaria. The test results were analyzed in accordance with Eurocode, JSCC and ISO with the aid of Microsoft Excel, SPSS, EasyFit and COMREL software packages. The reinforcement steel parameters were checked for outliers and the PDF of the reinforcement steel parameters were analyzed using the Kolmogorov-Smirnov goodness of fit test. The outcome of the research shows that the reinforcement steel diameters are significantly lower than specified standard sizes recommended by ISO 6935-2:2007 and BS4449:1997-2005. (i.e. 9.68<10mm, 11.40<12mm, 15.35<16mm, 19.18<20mm, 24.28<25mm), and the elongation of the reinforcement steel ranges from 11.89-14.48% with only diameter 20mm and diameter 25mm bars meeting the minimum of 14% as specified by BS4449:1997-2005 and ISO 6935-2:2007 which indicates that majority of the reinforcement steel are less ductile. More also, the reinforcement steel diameter follows a Log-Normal distribution, the yield strength and ultimate yield strength fits a Gumbel(Min) and Gumbel(Max) distribution respectively, while the design values of the reinforcement steel are 8.9mm for diameter, 411.42 N/mm2 for the steel yield strength and 734.79 N/mm2 for the reinforcement steel ultimate strength. Hence, the study recommends that a reliability based method of calibration should be done in order to obtain a suitable safety factor and other necessary reinforcement steel parameters that can be adopted for the reinforcement steel.

We present a numerical solution for the dead zone model which describes the solute transport in a subsurface and horizontal flow constructed wetland. This model is a system of two mass balance equations for two conceptual areas: the main channel and the storage zone. We use finite difference schemes to determine the numerical solution of the system and we study its convergence by presenting properties related to the stability and accuracy of the schemes. Concerning the experimental results, the magnitude of the longitudinal dispersion and the extension of dead volumes is estimated for clean conditions and after a certain operating period under organic loading conditions. The results showed a considerable amount of longitudinal dispersion through the bed, which was very strong near the feeding point, indicating the occurrence of mixing and significant presence of dead zones and short-circuiting.