Repairing of reinforced concrete beams by using thin fibers concrete jacket have many advantages such as increasing of ultimate load, enhancement of serviceability limit state, resistance to fire and avoiding of corrosion problems that appear in steel plate jacket. This paper reports investigations conducted to study the repairing of reinforced concrete beams subjected to short time repeated loading by using mixed steel fibers concrete jacket (MSFCJ). For this purpose, eight reinforced concrete beams have 120×300×2300 mm dimensions were fabricated and tested under three point load. The used concrete mix contains two mixed shape of steel fibers, corrugated and end-hooked steel fibers. Two of these beams were fabricated without jacket, the first was tested under static load up to failure and the second was tested under short time repeated loads up to failure. The rest six beams were loaded up to 0.5 the ultimate static load and then repaired by U-shape jacket (MSFCJ) with various thickness and steel fibers content. The test results showed the effectiveness of the proposed technique in the behavior of such beams.

This study is done to discuss nonlinear static behavior for cable-stayed bridges, hence develop a set of consistent design as well as a feasibility study of long span cable-stayed bridges over Nile River. In order to accomplish this goal, a thorough investigation of important key design parameters to determine the behavior of cable-stayed bridge and identify any gaps in current knowledge is done to be filled in order to enable the formation of a consistent set of design recommendations. Three span cable stayed bridge has been analyzed, the effects of the variation of different key design parameters: cross section of cables, cable layout either fan or harp pattern, pylon height to span ratio and mechanical properties of deck and pylon on the straining action of the bridge elements are investigated. The loads on the cable stayed bridge are a symmetrical load such as the own weight of all structural elements and live loads. The results related to the major factors to choose the ratio between the bending stiffness of a deck and axial stiffness of the cable to reduce bending moments and deflections in the deck and pylon are presented and discussed. Finally, some conclusions related to the cable stayed bridge’s analysis/design are drawn.

This study investigates experimentally and theoretically the effects of operating and configuration parameters on convection heat transfer process and fluid flow characteristics for air flowing in transitional regimes through parallel plate channels with staggered plates segments heated by radiant heat flux. This configuration is to be utilized in air heater solar collectors and/or in a combined photovoltaic and air heater solar collector systems (PV/T). The operating parameters tested were Reynolds number (Re) values ranging from 2580 to 4650 with a combination of incident radiation heat flux (qinc) values of 400, 700, and 1000 W/m2, respectively. The experimental results show that the local Nusselt number (Nux) is not unique function of the axial distance, in addition, a linear relationship between Re and apparent friction factor (f) was observed. Moreover, the model results show that combination of Re values in the laminar flow regime with proper selection of both plate's length and thickness can lead to enhancement in the heat transfer from the plate segments to the air stream. This is due to self-oscillatory flow mixer in wake zone behind each plate segment. Consequently, this will lead to avoid the need of more pumping power for the case of the flow falling within the transitional regime in the channel.

This study investigates experimentally and theoretically the effects of operating and configuration parameters on convection heat transfer process and fluid flow characteristics for air flowing in transitional regimes through parallel plate channels with staggered plates segments heated by radiant heat flux. This configuration is to be utilized in air heater solar collectors and/or in a combined photovoltaic and air heater solar collector systems (PV/T). The operating parameters tested were Reynolds number (Re) values ranging from 2580 to 4650 with a combination of incident radiation heat flux (qinc) values of 400, 700, and 1000 W/m2, respectively. The experimental results show that the local Nusselt number (Nux) is not unique function of the axial distance, in addition, a linear relationship between Re and apparent friction factor (f) was observed. Moreover, the model results show that combination of Re values in the laminar flow regime with proper selection of both plate's length and thickness can lead to enhancement in the heat transfer from the plate segments to the air stream. This is due to self-oscillatory flow mixer in wake zone behind each plate segment. Consequently, this will lead to avoid the need of more pumping power for the case of the flow falling within the transitional regime in the channel.