Variation Orders in construction are often be accompanied with series of impacts on the quality, time, and cost of the projects. This issue requires proper analysis and action to develop quantitative methods to measure the reasons and effects of variation orders and make a complete assessment for them. This paper presents a study of the most important factors which are considered to have an impact on the time and the cost of the project during its life cycle stages for various governmental construction projects done in the Kingdom of Bahrain. The construction projects were in particular buildings, warehouses, facilities and government buildings with a contractual value of about 18.6 million US dollars. Those two dimensions of the variation orders (cost, time) are applied to these specific factors: Owner, Consultant, Contractor, Project Management, Local Authorities, and Force Majeure.Using questionnaire survey, replies received from 43 participants specialized in construction industry and various government and private sectors on the causes and effects of project changesto analyze the RISK significance index. The RISK significance indexindicates and sorts the most effective reasons causing variation orders. The results of the above mentioned analysisshowthat the owner is responsible for the most variation orders generated, and that the owner financial difficulties during construction stage has the most value of RISK significance index.

A questionnaire has been designed and presented to determine the most important criteria affecting the choice of the best consulting offices in construction projects in the public sector in Libya. The questionnaire consists of Ninety-nine sub-criterion covering on two main fields. The first field: human resources contain six main criteria and thirty-four sub-criteria. The second field: physical possibilities contain sixteen main criteria and sixty-five sub-criteria. The questionnaire is spreaded over expert engineers, to rate the criteria on likert scale, (1 to 5). The validity and reliability of the questionnaire have been tested to ensure that the collected data is meaningful. In order to ensure the veracity of the internal consistency of the questionnaire, the questionnaire has been distributed over the decisionmaker experts to calculate the correlation coefficient Pearson. In the reliability analysis, Cronbach's Alpha coefficient and arithmetic average of results have been determined utilizing the Statistical Package for Social Sciences (SPSS). Finally, the study shows that there are seven main criteria that mainly control the selection of the consulting office. These criteria are human capabilities, office experience, previous performance level, quality control, office equipment, administrative system, training and development.

Consulting offices selection is an important step in the success of a construction project. Selecting consultant offices in the Libya is often done by the criterion of lowest price. This leads to a lack of innovation and a loss of quality in the construction industry. In this paper, the multi-criteria decision-making (MCDM) is suggests to be utilized for consultant offices selection. The analytic hierarchy process (AHP) has been used as a tool for MCDM. Here, the used criteria are those previously concluded from a former study. These criteria are human capabilities, office experience, previous performance level, assurance and quality control, office equipment, administrative system, training and development. In the current study, two questionnaires have been designed. The first questionnaire is designed to determine the weights of relative importance of each criteria (main and sub-criteria). The answers to the questionnaire are analyzed using the Expert Choice program. The second questionnaire is designed to calculate the average rate of certain criteria. The weights of relative importance for each main and sub-criteria are used to assess a consulting office for both of design and supervision stages. Finally, an administrative buildings project is assumed and it is required to select an office out of four offices (A, B, C, and D) using the proposed methodology.

The present work is established to determine the analysis of the arched composite beam and the studied parameters compared with the straight one. A computer simulation program, using SAP package, was used to predict the elastic state performance for both arched composite beam and straight composite beam. The parameters studied in the analysis using finite element model of the arched composite beam are different spans (30m, 40m and 50m); different percentages of degrees of curvatures (0%,2%,4%,6%) and different spring constant. [3] The performance of the arched composite beam showed that, when the degree of curvature increased to percentage of 6%, the tensile stress decreases to 70%, the compressive stress decrease to 70%, the deflection decrease to 70% and the horizontal reaction decrease with 53% relative to straight beam. Also using springs at end support of stiffness K (Max-horizontal reaction in case of hinged-hinged support / Max-horizontal displacement in case of hinged-roller support) decrease horizontal reaction 40% relative to hinged-hinged support. 1-Parametric StudyTwo main criteria should be fulfilled, in order to achieve a successful structural analysis. The criteria are the selection of a suitable model to represent the structural system and then perform the analysis of this model with a reasonable degree of accuracy. [2]

The problems associated with water loss are numerous. High real losses indirectly require water suppliers to extract, treat, and transport greater volumes of water than their customer demand requires. The additional energy needed for treatment and transport taxes energy-generating capabilities which often rely upon large quantities of water in their process. Leaks, bursts, and overflows often cause considerable damage and inflate liability for the supplier.The main objective of the current research is to find the direct relationship between the losses in water distribution networks and the residual chlorine. The experimental program is designed to monitor the losses in water distribution networks and how it can be related to the residual chlorine in a certain part of an existing network. For this purpose, a certain measurements on a part of a water network in Nasr-City, Cairo, Egypt have been made to find residual chlorine relationship with time and pipelines lengths and amount of leakage. The field measurements of both the rate of flow and the value of the residual chlorine at different locations and at consecutive intervals of time were carried out through three steps (runs). The first run for a single pipeline, the second step for three pipelines while the third run for the whole part of the network (nine pipelines).Two main equations are concluded from this field measurements and analysis. Equation (1) represents the relationship between residual chlorine, time and pipeline length, and equation (2) represents the relationship between residual chlorine and leakage with pipeline lengths. The results from these equations verification showed that, deviation percent between field measurements and the application of the equations is minor and within allowable rate.