رشا عبد الرضا غني الجزائري

As an extension of recent developments in concrete understanding, an extensive study is currently being conducted on the structural performance of reactive powder concrete (RPC). The paper guides how to investigate the shear behavior of RPC T-beams and calculate their ultimate and breaking shear capacities. The mechanical features of this construction material and approach to revising the reactive powder shear hybrid segment T- Beams are cast-off in this motion and are investigated in this experimental study. To evaluate the effects volumetric ratio of steel fibers, silica fume ratio, and tensile steel ratio, the hybrid section on reactive powder efficiency of T-beam shear, the program of experimentation involved trying four beams. The research aimed to determine the deflection conduct of the load, downtime approach, strain amount over the beams' depth, and failure form of cracks. In examining reaction powder's mechanical characteristics mixtures, steel fiber volumetric and silica fume volumetric ratios were too studied. Furthermore, a hybrid beams study revealed that using reactive powder web and regular concrete in flange effectively enhances T-beam concert when associated with normal concrete T-beams by 12%. Hybrid beams have also revealed that using reactive powder flange and usual concrete in a web effectively advances the show of T-beams when associated with standard concrete T-beams by 28%.

Reactive powder concrete (RPC) is one of the most recent and significant advancements in the world of building. Due to its higher concrete characteristics, it has a common excessive benevolence happening in the globe at the moment, excessive ductility, shrinkage resistance, and corrosion and abrasion resistance. The approach to revising the RPC is investigated experimentally in punching shear slab action and the properties of construction material to investigate properties of Volumetric ratios of steel fiber, and silicas fume, tensile steel ratio, the most important component for construction is reinforced concrete, which works well with other materials to create structures in any shape that is needed. In the present research, investigational work of RC slab with (1000 × 1000 × 60) mm, dimensions was tested. This study aims to see how the relative volume of steel fibers (Vf) and silica fume content (Sf) affect the actions of RC slabs after being exposed to Fire. It originated that a concrete mix containing 2% steel fibers improved the RPC slab's cracking and final punching shear. The existence of reactive powder increases fire resistance. This study's experiment aimed to see how reactive powder and Slab's ultimate punching shear strength was affected by replacement ratio. When exposed to Fire. After fire exposure, the initial and subsequent stiffness of reinforced concrete slabs reduced considerably as the temperature grew from 25 to 750 ° C.

Concrete curing is an essential stage in concrete making. In this study, an internal curing agent was utilized instead of normal curing (water curing) to complete the cement hydration process. Polymer gel extracted from baby diapers was used as a curing agent because it has a high absorption capability and water-retention property. Self-compacting concrete (SCC) was selected for this study and different percentages of gel polymer (0.5%, 1.0%, and 2.0% of cement weight) were investigated. A concrete mix with 0% gel polymer and water curing was used as a control mix for comparison purposes. Concrete fresh properties such as slump flow, T50, temperature, and density were monitored and also concrete hardened properties such as compressive strength, tensile strength, absorption, sorptivity, pules velocity, and density were investigated. Test results show that concrete with 0.5% gel polymer gave a comparable performance to concrete without gel polymer and underwater curing.

This study shows how to deal with the waste in the environment and add it as raw materials in concrete mixtures and the extent of the impact of these materials on the resistance of concrete mix and the durability of the model used to improve the environment conditions and to reduce the cost of raw material. Select the remnants of plastic bottles and remnants of iron filing and the adoption of the ratios of the addition of residues on a previous research by selecting the best results obtained in research, where the six samples were examined B1 was beam reference with a concrete mix to be compared with the models that contain the waste, model B2 was added (2%) plastic fibre of the weight of the cement , model B3 where 20% of the aggregate volume was replaced with plastic bottle caps, model B4 iron filings 2% of the weight of the cement, model B5 containing 2% plastic fibre with 2% of iron filings and model B6 replaced 20% of the volume of aggregates with plastic bottles caps and the addition 2% of the Iron filings as a percentage of the weight of cement. The results obtained were reasonable, plastic waste minimized compressive and load resistance, but with the addition of iron filings, the results were improved and increased resistance and load was observed.

Due to low values of mechanical properties of lightweight concrete , lightweight concrete is rarely used in structural members in buildings or structures , the lowest value of compressive strength can be used for concrete is 17 MPa, thus this investigation deals with improving the mechanical properties of two types of lightweight concrete , the first type is lightweight aggregate concrete (LWAC), and the second is no-fines concrete (NFC).

Fiber reinforced concrete is widely used in concrete structures, it has several benefits like increasing tensile, compressive, flexural strength and modulus of elasticity and also increases ductility and toughness of concrete.