No abstract

This study is devoted to investigate experimentally the ultimate strength capacity performance of seven dapped ends simply supported reinforced concrete beams with a (length, height, and width) dimension of (1200, 240, and 130) mm, either solid cross section or top/bottom hollow opening/s. One-point load test method results a different crack patterns of multi types of failure with varying intensity. It is found that the beams strength capacity values with openings less than the solid beams by 5-10%, while the deflection values of solid cross section beam contrary increased by 11-30%. Also, for the same location of opening the increase in hollow openings reduce the capacity load by 4.5-10%, but increase the deflection values by 6-12.5%. Finally, the beams with opening located at the compression zone decrease the load capacity and increase the deflection values by 5% than the beams with opening at tension zone. Therefore, this study handed to the civil engineering designer using the dapped ends beams in bridge construction structures under effect of static loads, “for the necessary purposes of installing power supply cable or water pipe, the authors recommended using beams with opening to be located at bottom fiber tension zone”.

In this article, the shear behavior of a deep beam made of Recycled Aggregate Concrete (RAC) was analyzed. Rapid urbanization has presented a massive new activity that is necessary to meet the needs of the influx of people. Developments of all types, from housing to infrastructure, necessitate considerable input from both natural and monetary resources. The purpose of this study is to compare the strength and loading capacity of RAC to that of Naturally Aggregate Concrete (NAC). The samples were evaluated at a controlled deformation rate of 2mm/minute in the "Material Testing Laboratory of the Department of Civil Engineering," where this investigation was conducted. The researcher has chosen two different sizes of coarse totals to use throughout this study: those measuring 5mm to 15mm (60.2%) and those measuring 15mm to 25mm (40.3%). In support of her claims, the researcher presents a variety of charts and datasets in the following research. There is an overall drop in strength in the recycled aggregate concrete samples. The load-deflection curves and the techniques are depicted by which the specimens failed. Shear required beams' experimental data and predicted values. This study reveals that compared to natural aggregate concrete, recycled aggregate concrete has weaker compressive, flexural, and breaking tensile strengths. The maximum load-bearing strength of longitudinally supported beams built of "recycled and natural aggregate concrete" is also not significantly different.