In reinforced concrete design, the concrete in the tensile zone is assumed to be ineffective and increase the dead load of the structural elements. In order to reduce the self-weight, this paper examines the structural behavior of reinforced concrete beams containing lightweight concrete in the tensile region and normal weight concrete in the rest of the beam. The lightweight concrete was made from waste polystyrene. Four reinforced concrete beams were prepared with different depth of lightweight concrete. The control beam B1 consists of normal concrete. In Beams B2, B3 and B4, the depth of lightweight concrete was 25%, 50% and 75% of the total depth of the beam measured from the bottom surface respectively. A four-point bending test was conducted on all beams. The beams were loaded in increments until failure. At each load increment, the central deflection was determined. Cracks initiation and the mode of failure were observed during the experiment. The failure load was found to decreases with the increase of depth of lightweight concrete. The presence of lightweight aggregate tends to cause brittle failure. In addition, the mode of failure for reinforced concrete beams containing lightweight concrete was a shear failure. arabic 11 English 79
Hakim S. Abdelgader(6-2020)

تتضمن هذه الورقة دراسة عن الجسور وتوظيف برنامج نظم المعلومات الجغرافية GIS لأرشفة معلومات عن هذه الجسور، فمن خلال البحث عن معلومات عن الجسور لدي مؤسسات الدولة المعنية بجسور داخل مدينة طرابلس تبين عدم وجود أي بيانات، مما تطلب حصر معظم الجسور داخل مدينة طرابلس وجمع المعلومات العامة والمتمثلة في ( الاسم، الاحداثيات، الطول، العرض، ومنطقة ربط الجسر) لعدد 51 جسر، وتم عمل دراسة تفصيلية عن ثلاث جسور واجراء فحص بصري ظاهري وجمع البيانات عن حالتها ووظائف عناصرها اذا كانت تشتغل بالشكل المطلوب وما بها من عيوب ام بصحة جيدة وبعد جمع بيانات الفحص البصري وتقييم حالة الجسور تم وضع هذه البيانات في بطاقات وربط كل البيانات التي تم جمعها في برنامج نظم المعلومات الجغرافية لأرشفتها الكترونيا ليسهل الوصول اليها في أي وقت من قبل المهتمين للحصول علي معلومات عن الجسور داخل مدينة طرابلس بطريقة سهلة وميسورة وفي اسرع وقت وتكون خطوة للاستغناء عن الارشفة الورقية. arabic 135 English 3
هيفاء علي رجب ابوحليقة(3-2020)

Abstract The digital photomaps which are produced from digital aerial photos have been presented in some detail in research work. This thesis focuses mainly on producing a rectified photomap and accuracy assessment of ground check point’s coordinates that are distributed in the chosen study area within a local region which has been used to develop a digital photomap for the urbanized Proposed study area that is located at a part of Tripoli City (anofleen region).Consequently, such as urbanized area the effect of tilt and relief displacement must be considered in the rectification mathematical model. Due to the rapid development in extending an urbanized areas which forms the major problem in developing countries where a lack of up-to-date digital large scale photomap which can be obtained with save money and effort to produce useful information for purpose urban planning . The Digital airborne imaging systems integrated with in-flight control systems consisting of Global positioning system (GPS) and inertial measurement units (IMU) that are used to provide the data needed to assist a rectification mathematical model to obtain a rectified digital photomap. Consequently, the thesis investigates the potential of using integrated sensors with a number of ground control points to produce a rectified photomap for study area which contains thirteen Digital images acquired from airborne digital camera at flight height 1100m which is main point for the contribution in the study (combination photogrammetric solution); consequently, the procedure is dependent on a comparison between result of photogrammetric solutions, which are obtained through direct and indirect approaches against a combined photogrammetric solution. To achieve and obtain usefulness information, twenty sharped and well distributed check points are chosen on the study area that are used to know the quality of the RMSE in planimetry and elevation at check points according to the adopted Map Standards Accuracy that are worked in surveying department of Libya (SDL), Some good results have been achieved in the study. Since by analyzing the result, which is found that the combination photogrammetric solution that have been given best result with respect to the geospatial accuracy, and which was chosen to produce a rectified photomap of digital aerial images for study area that are found the produced rectified photomap satisfied the theoretical large scale mapping of 1:1,000 according to the followed Map Standards Accuracy (SDL).
عبدالمنعم اعبيد (2013)