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Abstract

Romania, due to its historical background, has many vestigial belongings to the cultural heritage, out of which the most noticeable (by number, age, architecture, symbolism and representation) are the wooden churches. Under these circumstances the role of the current study is to emphasize certain practical aspects (focused on the need to assess, preserve, restore and valorize) regarding the use of modern technology based on photogrammetry and 3D scanning. The case study was represented by the “Saint Martyrs Constantin Brȃncoveanu and His Sons” wooden church from Oradea Municipality, Bihor County, Romania; the edifice being included on the list of historical monuments ever since 2010. The final goal being to create 3D models for both the exterior and interior of the monument for research, restoration in case of need, sharing for education, entertainment, tourism purposes etc.

Abstract

In the construction process of modern buildings, the aim is to achieve maximum comfort within minimum energy consumption. One of the ways to achieve this requirement is the accurate determination of the volumetric flow rate of fresh air, necessary to ensure the required indoor air quality. This study begins with the experimental determination of carbon dioxide (CO2) concentration in an office room with one occupant performing three types of activities with different levels of physical intensities. Based on these measurements, a methodology for the precise determination of the volumetric air flow rate is presented. This method was compared with another one that takes into account body parameters and is considered in this study as the most accurate. The required outdoor air flow rate for the experimental room was also determined based on the present legislations of five different countries. Comparing all the studied methods and considering as refence the method based on body parameters, it was found that the accuracy of the values is influenced by the physical intensity of the activity and that most methods generally underestimate the amount of required fresh air.

Abstract

Among the important phenomena caused by tunnel excavations, the settlements on the ground surface can be mentioned, which are particularly important for shallow tunnels excavated in urban areas, and especially when passing under residential areas of cities. Numerous methods such as mathematical (numerical and analytical) ones can be used to predict surface settlement. This study was conducted aimed at using modern techniques such as artificial neural networks to analyze the parameters affecting the occurrence of surface settlement during forepoling tunnel excavation. Tabriz Subway project is a good opportunity to examine the effect of forepoling tunnel excavation the surface settlement in a granular soil with average groundwater level offers. None of the performance parameters (such as the features of the forepoling protective umbrella) and the environmental features (such as the geological effects and tunnel geology) establish a unique relationship with the surface settlement, but several factors together do so. In this study, the forpolling tunnel was modeled using Plaxis software and analyzed in various geotechnical conditions (drained, partially saturated and saturated) under static and dynamic loading. Finally, the values of the surface settlements were examined.

Abstract

The increase in Carbon Dioxide (CO2) gas emissions during the production of cement have increased the necessity for the development of eco-friendly sustainable concrete using alternative binders. This research was conducted to study the strength behaviour in terms of compressive and flexural strength of concrete incorporating rice husk ash (RHA) as a supplementary cementitious material. RHA is a potential alternative binder due to its pozzolanic nature but it can partially replace cement to a certain amount, beyond it, the strength decreases making the concrete less viable. Therefore, to strengthen RHA-based eco-friendly concrete, Polypropylene (PP) fibres were used to reinforce concrete. Based on the results, it was observed that 5% RHA achieved higher strength than the control sample, however, a further increase in RHA content resulted in a significant decrease in strength. Concrete with 10% RHA which showed reduced strength was reinforced with PP fibres which resulted in a gain in strength.

Abstract

Monetary concerns in structural schemes cause serious ramifications that may impede the expansion of schemes and impact the entire fiscal conditions of any country. The study highlights the issues of finance procrastinates in construction schemes. Aim to find the prominent issues on finance-related hurdles, which lead to production obstructions and to explore do able resolutions to overcome monetary connected production delays. The date was accumulated via a survey-based questionnaire and followed by the survey-based interviews. The responses were concluded from the amalgamation of clients, advisors, bankers, and brokers in the questionnaire. Brokers’ unsteady monetary conditions. Customers’ weak monetary and trade administration hinders in getting financial support from financers besides inflation were found as the most prominent problems. The outcomes highlight customers have the most significant function in reducing the influence of monetary issues regarding scheme procrastination. Suggestions and recommendations to reduce monetary-related procrastinations are presented accordingly.

Abstract

The Earth’s large amount of thermal energy is virtually an inexhaustible resource often placed too deep in the ground. Making use of this kind of energy is possible in limited areas. In this paper we analysed a GSHP system, in Galati city (Romania), for which we monitored the available thermal energy. For the analysis we used operational reliability theory, the concept of degradation, which in this case means a reduction of the ground’s thermal capacity as a result of continuous exploitation, meaning low temperature of the thermal agent used for transporting the heat from the ground to the primary exchanger of the heat pump. The decrease of thermal energy supply in the ground means that the heat pump wills no longer function properly in order to provide the energy for heating the building. The term time to failure refers to the time when the ground can no longer provide the minimum required energy for the heat pump operation, in terms of energy efficiency. What we want with this approach is to offer a solution in order to control and manage the heat pump operation.

Abstract

In developing countries like Pakistan, Due to rapid growth and population, an increase in the production of industrial waste is rising significantly day by day. Stabilization of soil using those industrial wastes not only gives proper usage of waste materials but also increases the cost-benefit ratio as a whole. In this research work, an attempt was made to use Ground granulated blast furnace slag (GGBFS) in the stabilization of District Khairpur Mirs’ soil. Generally, while dealing with building construction industry such as foundations for buildings, highways such as subgrades as a foundation and in earthen dams as landfills sometimes there exist naturally occurring unsuitable soils. District Khairpur Mirs’ soil is accounted for the different laboratory tests and the concerned District Khairpur Mirs’ soil found to be relatively unsuitable; therefore, various percentages of ground granulated blast furnace slag were added to make it suitable. To improve the concerned soil different percentages of slag are used, and samples thus formed so for were tested in the laboratory for this research work. Various laboratorial tests like particle size distribution, Atterberg limits, Modified Proctor test, AASHTO soil classification, and CBR test were performed on controlled and stabilized soil samples. The aim of this research study was to examine the influence of ground granulated blast-furnace slag (GGBFS) on the index, Compaction and mechanical strength parameters of natural Khairpur Mirs’ soil. Finally, based on laboratorial tests, it was observed that stabilization of soil by GGBFS made favourable changes on the index, compaction and strength parameters of District Khairpur Mirs’ soil.

Abstract

In this study, mathematical modeling of permeation grouting through fully saturated soil is proposed based on immiscible multiphase flow theory. Grout flow in the medium is modeled together with the existing water as the simultaneous flow of two immiscible fluids. In the model, the porous medium is assumed as isotropic and rigid, fluids are assumed as incompressible and capillary pressure is assumed as negligible. Governing equations are discretized using upstream weighted finite element technique and results show that, proposed models give good results and may be used in the numerical simulation of grouting through fully saturated soils.

Abstract

In this article, the optimum design of a reinforced concrete solid slab is presented via the Mouth Brooding Fish (MBF) algorithm that is recently developed. It is based on mouth brooding fish life cycle. This algorithm utilizes the movements of the mouth brooding fish and their children’s struggle for survival as a pattern to find the best possible answer. The cost of the solid slab is considered to be the objective function, and the design is based on the ACI code. The efficiency of this algorithm is compared with Neural Dynamic (ND) and Particle Swarm Optimization (PSO). The numerical results indicate that the MBF algorithm can to construct very promising results and has merits in solving challenging optimization problems.

Abstract

Nowadays, many hydrological rainfall-runoff (R-R) models, both distributed and lumped, have been developed to simulate the catchment. However, selecting the right model to simulate a specific catchment has always been a challenge. A proper understanding of the model and its advantages and limitations is essential for selecting the appropriate model for the purpose of the study. To this end, several studies have been carried out to evaluate the performance of hydrological models for specific areas (mountainous, marshy and so on). This study was conducted aimed at evaluating the performance of MIKE11 NAM lumped conceptual hydrological rainfall-runoff model in simulation of daily flow rate in Gonbad catchment. The NAM model was calibrated and validated using flow rate data of three hydrometric stations of the Gonbad catchment. The model performance was evaluated using Percent bias (PBIAS) and the coefficient of determination or Nash-Sutcliffe coefficient. A Nash Sutcliffe efficiency (NSE) of 0.80, 0.89 and 080 were obtained during calibration, whereas, for the validation period, NSE of 0.81, 0.87 and 0.71 were obtained for Nemooneh sub catchment, Shahed sub catchment and Gonbad catchment respectively. Percent bias of -0.6, 1.5 and 6.3 were achieved for calibration, while -2.7, 7.6 and -4.2 were acquired during validation for Nemooneh sub catchment, Shahed sub catchment and Gonbad catchment respectively. Based on the results, the MIKE 11 NAM lumped conceptual model was capable of simulating daily mean flow rate and mean flow volume.