Journal of Civil Engineering and Structures

Estimation of the subgrade reaction modulus using field and numerical analysis methods

Salar Khaiiatali — 2024-02-26

Subgrade soil's reaction coefficient is of high importance in designing superficial structures. Different researches have been made in determining ultimate bearing capacity of shallow foundations. The ultimate bearing capacity of shallow strip footings is generally determined (Terzaghi, 1996). Especially in metropolises, the increase in the number of building stories and subsequently increase in loading measure on underlying soil makes this matter more important. So far various methods have been applied to estimate the suitable level of this coefficient which most substantial ones include various empirical relations, types of numerical modeling and using field experiments. In present study the value of this coefficient for the soil of Fereshteh alley district in Tabriz has been determined through various empirical and numerical ways and field experiments of plate loading and in the end an equation has been provided to estimate the subgrade soil's reaction coefficient.

Multivariate statistical evaluation of ground water quality

Salar Khaiiatali — 2024-04-12

In this study, the statistical results for the underground water of Qaem Shahr plain were evaluated. This evaluation is particularly important due to the main concerns of drinking water, irrigation, and sustainable agriculture in the region. Farmers rely on underground water as a supplement to surface water for irrigating their fields. Given the significance of this issue, the primary objective of this research is to study the water quality in the case study.

Multivariate statistical analysis has become increasingly popular for quantifying the relationship between water quality parameters and processes in groundwater aquifers. In this particular study, data were collected from water samples taken from 22 wells in the years 1999 and 2011. By analyzing these samples, we sought to identify the elements that have a significant impact on the quality of the unlimited coastal aquifer of Qaem Shahr plain. Our investigation focused on the wells in use and explored the influential processes that affect water quality in the aquifer.

The water samples were analyzed using multivariate statistical analysis, which involved measuring the concentration of cations and main anions, as well as parameters such as EC, T.D.S, pH, and hardness. For this study, we utilized multivariate statistical methods, including factor analysis (FA), and water quality indicators such as WHO and CCME classifications.

Investigate the Effect of Concrete Shear Wall Arrangement on the Roof Diaphragms Stiffness and Floor Shear Transfer in Steel Buildings

Mohammad sadegh Khajooei — 2024-02-26

Civil engineering considers the importance of reinforcement of structures against the loads applied to them during the structure lifetime, along with efforts to optimize and observe the design economy. According to a structural designer, the best form of a structure is when the leading structure members can withstand different loads optimally. In practice, however, non-structural considerations generally play an inalienable role in the choice of structural form and system, which can sometimes be very decisive. The number is one of the influential factors in the location and shape of strong lateral elements in structures, especially shear walls with an important and decisive role in the actual performance and behavior of the structure and the effective structural elements. This paper investigates the syntactic effect of shear wall arrangement on the roof diaphragms’ stiffness. Many structural designers, in designing conventional structures, despite the importance of the issue, neglect to carefully and occasionally examine the adequacy of diaphragm stiffness under the influence of wall arrangement in practice. Thus, three models of buildings with metal structures including 4, 6, and 8 roofs and three samples of each, i.e., nine computational models, were modeled, analyzed, and designed. The models were considered with a block joist roof on type III soil. Their construction site was Sabzevar in Khorasan Razavi province. After modeling, analysis, and design, two cases were compared with parameters such as relative displacement of floors, maximum diaphragm displacement, and shear and flexural forces in shear walls. Then, the stiffness of the diaphragm was checked according to the instructions of Annex 6 of 2800 regulations. This paper shows that the shear wall arrangement has a significant role in determining the stiffness of the roof. In this study, by changing the shear wall arrangement, 4, 6, and 8-floor models’ stiffness was reduced by 146%, 148%, and 668%, respectively. Furthermore, by changing the arrangement and increasing the displaced shear wall’s stiffness of the studied models decreased by 339%, 1003%, and 900%, respectively, and the ceiling of all three models changed from rigid to semi-rigid.

A Review on Application of Glass Fiber-Reinforced Polymer as a Strengthening Material for Unreinforced Masonry Walls

Mohammadreza Moradi — 2024-03-09

Since the Unreinforced masonry structures are prone to dynamic loadings induced by earthquakes, a thorough comprehension of the behavior of these structures will help to improve their seismic performance. On the other hand, seismic performance improvement of unreinforced masonry walls was a very vast field of investigation. The primary aim of this paper is to study the comparison between the response of the unreinforced and strengthened model, Furthermore, the failure debonding mechanisms of strengthened shear wall models with glass fiberreinforced polymer (GFRP) are discussed. A systematic review of the literature was conducted on the topic with a major focus on the arrangement of the observation used GFRP materials for strengthening techniques, theoretical/analytical prognostication equations formulating the experimental investigations in the research, determination of the progress in the research areas, and identifying the gap in the literature. Eventually, a systematic review of literature will assist in identifying the gap in the knowledge about the Masonry walls reinforced with GFRP and determine the most critical design parameters affecting the structural performance of these types of structures.