Cost Evaluation and Management for Adopting Reinforced Earth Retaining Structures in Jordan

Globally, different studies and investigations in the field of new technologies and alternative building materials are continuously performed to decrease the cost and time of carrying out construction projects. In this research, a geotechnical and management investigations were conducted to evaluate (primarily) the cost of adopting reinforced earth retaining structures in Jordan and then to compare this technology with conventional concrete retaining walls. In Jordan, the reinforced earth technique is relatively performed, since 2005; however, it is still not popular among the construction engineering sectors. The methodology of this research consisted of two stages. The first stage included collecting for literature of previous investigations and the required information related to the above subject; whereas, the second stage focused on the idea of adopting reinforced earth structures for a proposed project in Jordan, then considering it as a case study for this research. Briefly, the study project was a proposed retaining wall that to be executed along one side of an existing road located at Al Fuhais City (about five kilometers from the Capital Amman). Accordingly, a comparison study for implementing two alternatives of retaining structures had been conducted for this project (i.e., reinforced earth & reinforced concrete retaining walls). The engineering evaluation of carrying out this project has been studied during performing a comprehensive analysis for each alternative considering the structural cost, labor and equipment's costs, quality and availability of the required materials, applicability, and the construction management. Considering the results of this research, it was concluded that conducting reinforced earth retaining structures in Jordan has more benefits considering their lower cost, less duration of execution, the availability of materials, the presence of workers with good experience, in addition to other several factors concerning the structure's durability, and serving as projects with most convenient to local environment. Keywords: Reinforced Earth Walls, Engineering Management, Cost Evaluation, Planning, R.C Walls

Expert System to Manage the Safety Requirements for Concrete Works Related to Jordanian Construction Projects

Numerous investigations that had been conducted in Jordan to evaluate the safety management in carrying out construction projects revealed that the implementation of this item is relatively below the desired level. In this research, a specialized software (Expert System) was proposed to improve the current situation regarding the application of the right rules in safety management for concrete works related to Jordanian construction projects. The proposed system contains a lot of ideal terms, specifications, and standards for conducting an acceptable safety management and for getting rid of (or reducing) accidents and other types of risks inside the project site. As a conclusion derived from this research, Expert System is aimed at enhancing the existing situation regarding the safety management for construction projects, and therefore to keep the workers and other staff to be away from all kinds of public risks inside the construction project, and accordingly the proposed software is recommended to be adopted in following up the application of safety management procedures in construction sites. Keywords: Safety Management, Concrete Works, Expert System, Construction Projects, Safety Requirement

Quality Evaluations for the Office Works and Laboratory Tests Related to Site Investigation Studies in Jordan

This research aims at conducting evaluations for the quality of the office works and laboratory tests concerning site investigation studies for construction projects in Jordan.The applied methodology for this research comprises four phases. The first phase was focused on identifying factors, methods, and literature review of the international standards in implementing site investigations. The second phase was concentrated on designing a questionnaire regarding opinions in performing site investigations in Jordan (in accordance with the international standards), and then distributing it to several engineers and experts who work at site investigation offices. The next phase was the analysis of the collected data that resulted from the distributed questionnaire using SPSS Software. Whereas, the last phase of the methodology was focused on developing for guidelines and preparing for conclusions.Based on the analysis of the received data related to the distributed questionnaire, the results indicated that various factors may affect the quality of the office works and laboratory tests related to the intended investigations. In general, it was concluded that the most important factor of these was the lack of commitment with the requirements of the Jordanian Code of Site Investigation, in addition to the lack of commitment to carryout laboratory tests based on the latest standards (specifications). Also, site investigation reports were almost free of containing detailed descriptions of geological profiles that derived from boreholes. Furthermore, these reports contain very limited information regarding the existence of water table or other sources of ground water. Keywords: Site Investigations, SPSS Software, Questionnaire, Laboratory Tests, Quality Evaluations

Comparative Study of Load Carrying Capacity of Steel Tube Columns Filled with Lightweight Concrete and Normal Concrete

Tests on steel columns filled with normal concrete and lightweight concrete were carried out to investigate the actual behavior and the load carrying capacity of such columns. Eight full scale rectangular cross-section columns filled with lightweight aggregate concrete and normal weight aggregate concrete, four specimens each, were tested under axial loads for comparison purposes. The results showed that using lightweight concrete filling instead of normal concrete filling will reduce the weight of columns. At the same time, a high load carrying capacity is achieved

Dissolution of Gypseous Rocks under Different Circumstances

The influence of temperature, flow velocity, gypsum content, salinity of solvent and hole diameter on the amount and rate of dissolution of gypseous rock samples was investigated. The rock samples were obtained from the proposed Al-Fat’ha dam site located approximately 280km to the north of Baghdad city. The gypsum content for these samples ranged from 16% to 90%. Dissolution tests were carried out with the aid of a special system that was modified and manufactured to allow passing water at different speeds through a drilled hole along the center of the rock samples. The amount of dissolution of gypsum was determined under different conditions. The results showed that the amount and rate of gypsum dissolution increased with increasing the temperature of the test. The effect was more pronounced on rock samples with low gypsum content. Increasing the flow velocity also increases the amount and rate of gypsum dissolution. With this parameter, the effect of gypsum content was marginal. Increasing the salinity of the solvent (using low percentages of NaCl additives) has a great influence on the amount and rate of gypsum dissolution, and further increase in the salinity exhibited a marginal increase in the amount of dissolution when compared with the lower salinity concentration. The Tigris river water (as a natural solvent) exhibited a negligible effect on the amount and rate of gypsum dissolution. Increasing the diameter of the hole along the center of the sample increases the inside area exposed to water and hence generates more dissolution

The Role of World Food Programme in Improving the Conditions of the Syrian Refugees in Jordan

The study aimed to search in the role of world food programme in improving the conditions of the Syrian refugees in Jordan. The study followed the descriptive analytical approach, and the sample consisted of (220) Syrian refugees inside and outside the Zaatari camp in Jordan, and the study tool, which is represented in the questionnaire, was developed, and the study found that the level of improvement in the living conditions of Syrian refugees in Jordan as a result of the World Food Program came with a medium degree, as it reached The study indicated that the level of improvement of the health conditions of Syrian refugees in Jordan as a result of the World Food Program came at a moderate degree, and the study found that there were no statistically significant differences in the estimates of Syrian refugees in the extent of the contribution of the World Food Program to improving conditions for refugees in Jordan according to the gender variable, and the presence of differences according to The location variable came in favor of the refugees inside the camp, and the study recommended increasing the allocations provided by the governments of the world countries to support the World Food Program to better provide its services. Keywords: World Food Programme,  Syrian Refugees DOI: 10.7176/JEP/11-18-16 Publication date:June 30th 202

Sc0.43(2)Rb2Mo15S19, a partially Sc-filled variant of Rb2Mo15S19

International audienceThe structure of scandium dirubidium pentadecamolybdenum nonadecasulfide, Sc0.43 (2)Rb2Mo15S19, constitutes a partially Sc-filled variant of Rb2Mo15S19 [Picard, Saillard, Gougeon, Noel & Potel (2000), J. Solid State Chem.155, 417426]. In the two compounds, which both crystallize in the Rc space group, the structural motif is characterized by a mixture of Mo6Si8Sa6 and Mo9Si11Sa6 cluster units ('i' is inner and 'a' is apical) in a 1:1 ratio. The two components are interconnected through interunit MoS bonds. The cluster units are centred at Wyckoff positions 6b and 6a (point-group symmetries and 32, respectively). The Rb+ cations occupy large voids between the different cluster units. The Rb and the two inner S atoms lie on sites with 3. symmetry (Wyckoff site 12c), and the Mo and S atoms of the median plane of the Mo9S11S6 cluster unit lie on sites with .2 symmetry (Wyckoff site 18e). A unique feature of the structure is a partially filled octahedral Sc site with symmetry. Extended Huckel tight-binding calculations provide an understanding of the variation in the MoMo distances within the Mo clusters induced by the increase in the cationic charge transfer due to the insertion of Sc

Experimental Study on Light Weight Concrete-Filled Steel Tubes

Tests on steel tubular columns of rectangular and circular sections filled with normal and lightweight concrete were performed to investigate the behavior of such columns under axial loadings. Comparison between normal and lightweight concrete filled steel columns for different column cross-sections using Euro Code 4 and BS 5400 codes was also conducted. The test results showed that both types of filled columns failed due to overall buckling; while hollow steel columns failed due to local buckling at the ends. According to these results, further interest was taken onto the replacement of normal concrete by lightweight concrete due to its low specific gravity and thermal conductivity

Development of Truss Linear Macro-Element

Macro-elements are among the powerful means in reducing the number of equations to be solved in finite element analysis. In the proposed method, several finite truss elements will be transformed into a single element called the macro-element. This is done by equating the potential energy of the macro-element to the potential energy of the equivalent truss finite elements. If the order of the macro-element function corresponds to the order of the structural behavior that it models, an exact solution is achieved. In this paper, a truss linear macro-element is developed. The developed macro-element was tested and the results were compared with the results of conventional finite element solutions and with closed form solutions. Excellent results were achieved with substantial reduction in the number of equations