https://www.isceiran.org/ Asas Journal en daily 1 Mon, 20 Feb 2023 00:00:00 +0330 Mon, 20 Feb 2023 00:00:00 +0330 https://www.isceiran.org/article_182631.html Construction is one of the most dangerous industries, with only about 7% of the world's workforce working in the industry, but about 30 to 40% of fatal accidents occur in the construction industry. People with low job satisfaction have poor job performance and are prone to accidents. This study aimed to investigate the relationship between health, safety, and environmental performance with job satisfaction and find a linear regression model to predict these factors in the Iranian construction industry. Therefore, the project of the Martyr Foundation and Affairs of Tehran was selected as a case study. First, a standard questionnaire of health, safety, and environmental assessment with control of its validity and reliability were prepared. Also, the standard questionnaire of job satisfaction Visoki and Chrome were used. Data collected from 126 labors who worked on this project and analyzed. Correlation were performed using SPSS software version 19 on the collected data. Findings indicated that a positive and significant relationship between most health, safety, and environmental performance indicators with job satisfaction indicators existed. Also, the highest correlation with job satisfaction was the relationship between personal importance and satisfaction with the workplace supervisor in which the Pearson correlation coefficient was equal to 0.434. Meanwhile, the regression analysis indicated that personal importance and job support are the most effective factors in predicting job satisfaction. The general results of this study indicates the relationship between HSE performance and job satisfaction in the Iranian construction industry is not much different from other countries. https://www.isceiran.org/article_185029.html Carried out studies on space structures signify the momentous influence of imperfections on the load bearing capacity of these structures. Many of these imperfections such as initial curvature in members are all innately random and can affect the bearing capacity of the members and consequently that of the structure. In this paper, the effects of the probabilistic distribution of initial curvature on the bearing capacity of flat double layer grid space structures with different pattern have been studied. 8 flat double layer space structures with different pattern were selected and 8000 nonlinear finite element analyses were done. At first, based on the random initial curvature imperfection amount of the member, the material property was updated. Afterwards, based on the push down analysis, the ultimate load bearing capacity of the structure was determined through nonlinear analyzes performed by the OpenSees software and this procedure was repeated numerous times. Finally, based on the Monte Carlo simulation method, the structure’s reliability diagrams were procured. The acquired results signify the sensitivity of the behavior of flat double-layer space grids to the random distribution of initial imperfections. https://www.isceiran.org/article_182014.html The current management system for concrete road bridges in Iran is primarily based on a descriptive model, which assesses the condition of bridge elements and assigns grades based on the level of deterioration. However, there have been concerns raised about the use of descriptive statistics when analyzing large amounts of data. In order to address these concerns, this research incorporates the data mining method known as decision tree analysis. The decision tree analysis involves in-depth examination of data, including objective observations by experts and calculations of damage indices. Paul has introduced this method to replace descriptive analysis in his research. To conduct this study, various data such as physical characteristics, atmospheric and climatic conditions, traffic conditions, and deterioration indices (derived from established formulas and tables) of concrete bridges with spans exceeding 6 meters on a main 5-axis road in Zanjan province were collected. The decision tree method, along with Rapid Miner software, was utilized to model and analyze this data. The research findings indicate that the decision tree method demonstrates a high level of accuracy in predicting and prioritizing factors that contribute to bridge damage, surpassing the capabilities of conventional models. Specifically, the study reveals that the percentage of heavy vehicles passing over a bridge is the most significant factor influencing its damage. Furthermore, it predicts that bridges with a percentage exceeding 19.5% would fall into the category of heavily damaged bridges. https://www.isceiran.org/article_181627.html As it is well-known, dispersive clay soils pose challenges in construction projects, so thus it requires modification and improvement. The main issue in this article is studying the effects of wollastonite powder on the geotechnical properties of dispersive clay soil. Wollastonite, a mineral substance is derived from natural limestone deposits, is used in various forms, such as fibers, tufts, or powders, which is used in multiple industries. Several tests such as pinhole, compaction, Atterberg limits, unconfined compressive strength, and CBR tests, are conducted on clay samples, which are containing different percentages (2, 4, 6, 8, and 10 percent) of wollastonite powder. The curing times of 3 and 7 days are also considered. The obtained results reveal that wollastonite powder not only increases the resistance parameters, but also can reduce dispersive potential. Added wollastonite powder to dispersive clay soil reduced the optimum moisture content to 8.89%. It increases the specific gravity to 1.62%, and the plasticity index decreased to 30.76%. Saturated soil samples had lower CBR strength than dry samples. Reaching up to 10% wollastonite content in The CBR test improves the strength of both saturated and dry samples significantly up to the enhancement of 89% (saturated) and 141% (dry) in comparison with original soil. Using 8% wollastonite powder, the compressive strength of the unconfined specimen is enhanced by 181% in 7 days as a result it has better performance than other samples. Also, it is noted that curing time is crucial item in stabilizing clay soils. https://www.isceiran.org/article_183928.html This paper aims to investigate the effects of retrofitting damaged unreinforced masonry walls using vertical concrete ties and bed rebar under both vertical and in-plane cyclic loading. An experimental program was conducted to test the masonry wall under a combination of constant vertical loads and cyclic lateral loads, following a specific loading protocol. The masonry wall was constructed to closely resemble the brick wall system commonly used in Iran and other South Asian countries by local construction workers. Initially, the unreinforced masonry wall was tested as a reference under vertical and in-plane cyclic lateral loads. Subsequently, the damaged sample was retrofitted by adding vertical concrete ties and bed rebar on one side, after which it was retested under the same loading conditions. The results showed that retrofitting the unreinforced masonry walls with vertical concrete ties and bed rebar not only restored the primary seismic characteristics of the walls but also significantly improved their seismic behavior. https://www.isceiran.org/article_176989.html The lateral behavior of cold-formed steel shear wall is dependent on several factors including the type of cladding used. However, only a limited number of cladding types have been studied using specific installation method. In this study, due to the high demands of builders to use local materials for cladding light steel frames, which in addition to being abundant and easy to obtain, can also create a variety of designs such as stone or brick to match the facade of existent parts of the building, two full-scale samples of cold-formed steel shear walls sheathed by porcelain ceramic with different configurations were tested under standard cyclic lateral loading regime. After calculation of ductility and response factors by using of specimens tests results, The seismic effect of the cladding rectangular panels array, which can be installed in either horizontal or vertical strips, was investigated. The results of the tests showed that porcelain cladding panels installation in vertical strips instead of horizontal strips caused a decrease of approximately 11% in ultimate resistance and 20% in seismic response modification factor, R.