The increasing use of high-strength concrete (HSC) for structures has been widely noticed in recent years. The risk of exposing these HSC structures to high-temperatures during a fire has increased significantly in Egypt. Consequently, the safety of such structures during and after a fire is important which depends on the mechanical properties of HSC structure elements subjected to high-temperature. The main objective of this study is to investigate the residual mechanical properties of high-strength concrete short columns with regard to high-temperature effects. This study presents the results of twenty-nine high-strength short columns 100×100×400 mm exposed to high-temperature cycle and tested under static loading up to failure. Different parameters were considered during this study such as percentage of longitudinal reinforcement, thickness of concrete cover, and temperature degree level. Experimental results showed that the compressive strength of high strength concrete has a little change until 400°C; however, beyond this degree of temperature a 55% reduction in the compressive strength was noticed compared with specimens at room temperature. Also, cooling of heated samples in water decreased the residual strength by 36% compared with their counterparts cooling in air.

The shear behavior of RC beams at failure differs utterly from their behavior by bending, that is taken into consideration to be a dangerous mode of failure. Shear failure of RC beams is often explosive and abrupt, whereas not spare advanced warning. Diagonal cracks propagate precipitately as a result of excess shear forces are significantly wider than the flexural cracks. The single Swimmer bar system is a new alternative of shear reinforcement. It is a small inclined bars, with its both ends bent horizontally for a short distance and tied to both top and bottom steel reinforcement. The single swimmer bar system can be spliced, welded or bolted. The present study simulates the effectiveness of using single swimmer bars instead of traditional stirrups on improvement of shear performance in reinforced concrete beams, as well as studying the effect of concrete strength and the type of tying to determine the most economical strength and the most effective type of tying to carry shear forces. Seven beams are experimentally tested under static load. The test results are given in shape of photos, figures and tables including modes of failure, both cracking and ultimate loads, the maximum deflections and maximum strains. The test results show that using swimming bar as shear reinforcement increase the shear strength and improve the deformability of the tested beams.

The shear behavior of RC beams at failure differs utterly from their behavior by bending, that is taken into consideration to be a dangerous mode of failure. Shear failure of RC beams is often explosive and abrupt, whereas not spare advanced warning. Diagonal cracks propagate precipitately as a result of excess shear forces are significantly wider than the flexural cracks. The single Swimmer bar system is a new alternative of shear reinforcement. It is a small inclined bars, with its both ends bent horizontally for a short distance and tied to both top and bottom steel reinforcement. The single swimmer bar system can be spliced, welded or bolted. The present study simulates the effectiveness of using single swimmer bars instead of traditional stirrups on improvement of shear performance in reinforced concrete beams, as well as studying the effect of concrete strength and the type of tying to determine the most economical strength and the most effective type of tying to carry shear forces. Seven beams are experimentally tested under static load. The test results are given in shape of photos, figures and tables including modes of failure, both cracking and ultimate loads, the maximum deflections and maximum strains. The test results show that using swimming bar as shear reinforcement increase the shear strength and improve the deformability of the tested beams.

In this book, I have put all the required information, equations, design curves and international seismic codes regarding the seismic design of RC bridges. The book website is http://www.morebooks.de/bookprice_offer_cf302f64444aedd8856 cc52287c59648bb9ad5e5?auth_token=d3d3Lm5vb3ItcHVibGlza GluZy5jb206NWJhNDQzZjFkMzA5OWNkMGU2NzY4MDZlZ DA3Mjc3ZWI%3D&locale=gb¤cy=EUR

The roof lateral displacement for RC frames is very significant parameter in performance based engineering and should be within acceptable limits as per the requirement of different performance levels. Data obtained from the time history dynamic analysis for a series of gravity load designed (GLD) RC frame was used as input data in a statistical program called SPSS 16.0, and a statistical analysis was done and a power equations was proposed to estimate the roof lateral displacement for the GLD RC frames. Three equations were proposed for estimating the roof lateral displacement.The first one is for the bare frame models, the second is for infilled frame models and the third is for infilled frame with open ground story. The equations for estimating the roof lateral displacement for GLD frames with different type of infill (bare, infilled and open ground story models) are proved to be acceptable accuracy and they can be used to estimate the roof lateral displacement for GLD RC frames if they meet the conditions set out.

The macro-models method is one of the main categories for modeling infills based on the equivalent strut method. The basic parameter of these struts is their equivalent width, which affects the stiffness and strength. This paper presents a general review of several expressions proposed by researchers to calculate this equivalent width. The comparative study of different expressions shows that the Paulay and Priestley equation is the most suitable choice for calculating the diagonal equivalent strut width, due to its simplicity and because it gives an approximate average value among those studied in this paper. Consequently, the model will be used in our further study for analysis of RC infilled frames.

phosphate ores and quarrying operations of marble and granite rocks. These wastes are stored in piles around or near mine sites, which are aesthetically unattractive and often degrading the environment. Various solutions have been sought for this major environmental problem and the best solution found is recycling. However, these wastes , because of their similarity to the conventional aggregates , represent a potentially useful source of material for a variety of applications ( in roadbed and dam construction , as railroad ballast ,as aggregate in concrete and asphalt mixes , …) The main purpose of this research is to investigate the possibility of utilizing the above mentioned three waste materials in road construction (base and sub base) and as a replacement layers for the problematic soil in foundations. Experimental tests were carried out on these wastes to assess their physical, mechanical and chemical properties, according to the Egyptian standards. The modified proctor and California bearing ratio (CBR) are the most important tests of soil compaction to assess the suitability of any waste materials. The CBR value of phosphate waste is 88% , 95% for crushed marble and about 41% for crushed granite. The obtained results proved that these kinds of wastes can be used in base and sub-base layers in road construction and as replacement soil under foundations. The potential uses of these wastes are considered beneficial from the economic and environmental points of view and saving the natural resources of aggregate.

phosphate ores and quarrying operations of marble and granite rocks. These wastes are stored in piles around or near mine sites, which are aesthetically unattractive and often degrading the environment. Various solutions have been sought for this major environmental problem and the best solution found is recycling. However, these wastes , because of their similarity to the conventional aggregates , represent a potentially useful source of material for a variety of applications ( in roadbed and dam construction , as railroad ballast ,as aggregate in concrete and asphalt mixes , …) The main purpose of this research is to investigate the possibility of utilizing the above mentioned three waste materials in road construction (base and sub base) and as a replacement layers for the problematic soil in foundations. Experimental tests were carried out on these wastes to assess their physical, mechanical and chemical properties, according to the Egyptian standards. The modified proctor and California bearing ratio (CBR) are the most important tests of soil compaction to assess the suitability of any waste materials. The CBR value of phosphate waste is 88% , 95% for crushed marble and about 41% for crushed granite. The obtained results proved that these kinds of wastes can be used in base and sub-base layers in road construction and as replacement soil under foundations. The potential uses of these wastes are considered beneficial from the economic and environmental points of view and saving the natural resources of aggregate.

This paper will present an investigation through theoretical study of the influence of the different strengthening techniques on the rendering of the reinforced concrete frames subjected to earthquake motion. In this study, diagonal cross bracing, infill wall brick, externally CFRP laminates, and reinforced concrete jacketing for columns only are considered as different techniques for strengthening of one story reinforced concrete bare frame. Time history analysis for RC frame subjected to EL-Centro (1940 N-S) earthquake ground motion is carried out using ETABS structural analysis software program. Variety of parameters as dimensions, mechanical properties of material and loads are considered for different cases in this study. The results that obtained from the time history analysis such as the relationships between the axial and shear stresses, lateral displacement, acceleration and base shear with time for the modeling frame. Are illustrated and discussed with/ or without the strengthening techniques. This study demonstrated the influence and enhancement of each technique on the performance of one story bare frame subjected to EL-Centro earthquake motion.

This paper will present an investigation through theoretical study of the influence of the different strengthening techniques on the rendering of the reinforced concrete frames subjected to earthquake motion. In this study, diagonal cross bracing, infill wall brick, externally CFRP laminates, and reinforced concrete jacketing for columns only are considered as different techniques for strengthening of one story reinforced concrete bare frame. Time history analysis for RC frame subjected to EL-Centro (1940 N-S) earthquake ground motion is carried out using ETABS structural analysis software program. Variety of parameters as dimensions, mechanical properties of material and loads are considered for different cases in this study. The results that obtained from the time history analysis such as the relationships between the axial and shear stresses, lateral displacement, acceleration and base shear with time for the modeling frame. Are illustrated and discussed with/ or without the strengthening techniques. This study demonstrated the influence and enhancement of each technique on the performance of one story bare frame subjected to EL-Centro earthquake motion.