salah talib nimnim alkhazaali

The direction of bolts and its effect on the bearing capacity of double shear bolted connections has been examined in this paper. Sixteen specimens with up to four bolts have been tested under tensile load. These specimens have been sorted into two series (L, T) according to the bolt direction with applied loads The experimental results have clearly indicated that the bearing capacity of connections had been considerably affected by changing the direction of bolts. With tear-out failure, All specimens of L series showed high bearing capacity and good ductility while block shear failure was the distinguishing feature of specimens of T series. الخلاصة اتجاة البراغي وتاثيرها على سعة التحمل للوصلات المزدوجة تم اختباره في هذا البحث . تم فحص ستة عشر نموذج. لقد تم تصنيف النماذج الى مجموعتين وحسب اتجاه البراغي مع القوه المسلطة . وقد اثبتت النتائج بان السعه التصميمية للوصلات المزدوجة تتاثر تاثيرا كبيرا بتنغير اتجاه البراغي وان النماذج التي بها البراغي باتجاة القوه اظهرت قوة تحمل عاليه مع مطيلية عالية وانها جميعها فشلت بخلع البليت بالكامل بينما فشل القص كان هو السمه السائدة لمجموعة النماذج ذات البراغي الموضوعة باتجاة عرضي مع القوة المسلطه

Abstract- The low cost construction demand has led to utilize timber as a construction material. The need for better strength in construction material has resulted reinforcing timber with steel elements. Six timber beams, reinforced with four steel angles at their corners, have been tested to investigate the combined beams behavior. Experimental tests and finite element method have been undertaken in the investigation process. A good agreement has been noticed between the experimental and finite element method in predicting the load carrying capacity for the test beams. It has been found that the stronger bond used between top and bottom angles, the more load carrying capacity for beams can be obtained and higher beams ductility can be achieved.

Abstracted- Reinforced concrete (RC) columns in buildings often need rehabilitation either due to defects in the columns themselves, having to support higher loads than those foreseen in the initial design of the structure, or as the result of ageing or accidental damage. The use of steel caging for this purpose is now a common practice in many countries throughout the world. In this paper, experimental works is presented to investigate the behavior of of reinforced concrete columns strengthened externally with steel jacket under axial loads. This experimental work comprises of twelve square reinforced concrete columns with same cross section of (120x120)mm and height of 1000mm. These columns divided to four groups, the first group (includes three columns) represents the control samples i.e without any type of strengthening, second group (includes three columns) strengthened by various sizes of four vertical steel angles at column corners linked by horizontal battens, third group (includes three columns) strengthened by constant sizes of four vertical steel angles at column corners linked by various sizes of steel plates at top and bottom of columns, while fourth group (includes three columns) strengthened by constant sizes of four vertical steel angles at column corners linked by (various sizes of steel plates at top and bottom of columns besides horizontal battens).The results show that the rehabilitation technique (strengthening) of R.C. columns by using external steel jacket can increase the ultimate load from (42.2-121.7)%.