The Effect of Low Velocity Impact Loading on Self-Compacting Concrete Reinforced with Carbon Fiber Reinforced Polymers

Low carbon steel with carbon content ranging from 0.15% to 0.3% cannot be hardened through quenching and tempering processes and there is little to no martensitic transformation occurring upon quenching. To improve the surface hardness, carburizing is commonly employed. Through this treatment, the surface composition of the low-carbon steel is altered by the diffusion of carbon, resulting in a hard outer casing with good wear resistance. This work investigates the effect of the carburizing treatment temperature and holding time on the crystallographic structure, hardness, and hardened surface layer dimension of commercial low-carbon steel 16NC6. The steel was carburized at 900°C for different holding times of 1, 2, and 3 hours. After the carburizing and quenching processes, the hardness values and the morphology of the crystallographic structure were measured and characterized.

Section: Introductionmentioning

confidence: 99%

An Experimental Study of the Influence of Carburizing Treatment Holding Time on the Structure and Hardness of 16NC6 Steel

Baali

Benarioua²,

Mazouz

2023

“…The bending energy is subtracted from strain energy to determine the fracture work. The rotating kinetic energy can be determined by (10), which involves integration over the length of the specimen and the assumption of a linear velocity distribution along the beam's length. The hammer's momentum is quickly transferred to the beam when it strikes it.…”

Section: B Energiesmentioning

confidence: 99%

“…Previous researchers have indicated that when a structural element is subjected to an impact load, it elicits two distinct responses: a local response and a global response. The local response is primarily caused by the stress wave generated at the impact point, whereas the global response arises from the subsequent elastic-plastic deformation over an extended period throughout the structural member [5][6][7][8][9][10]. The failure of RC beams under impact loading raises significant concerns, with localized failures such as penetration, scabbing, perforation, and punching shear being the most commonly observed types of failure in RC elements subjected to impact loads.…”

Section: Introductionmentioning

confidence: 99%

Theoretical Analysis of Composite RC Beams with Pultruded GFRP Beams subjected to Impact Loading

Ibrahim,

Alshaarbaf,

Allawi

et al. 2023

Glass Fiber Reinforced Polymer (GFRP) beams have gained attention due to their promising mechanical properties and potential for structural applications. Combining GFRP core and encasing materials creates a composite beam with superior mechanical properties. This paper describes the testing encased GFRP beams as composite Reinforced Concrete (RC) beams under low-velocity impact load. Theoretical analysis was used with practical results to simulate the tested beams' behavior and predict the generated energies during the impact loading. The impact response was investigated using repeated drops of 42.5 kg falling mass from various heights. An analysis was performed using accelerometer readings to calculate the generalized inertial load. The integrated acceleration record and the measured hammer load vs. time data were utilized to determine the generalized bending load and fracture energy. Four forms of energy were calculated at the maximum load. The total energy was calculated and divided into two parts: The first part was gained by the beam's rotational kinetic energy, the bending energy in the specimen, and the elastic strain energy. The second part was the hammer's kinetic energy before striking the beam. The analytical results showed that the bending energy was less than its rotational kinetic energy for the encased GFRP beams and the reference specimens. In contrast, the encased steel beams had high bending energy due to the higher impact load and deflection. Strain energy recorded lower energy values for all specimens with higher bending energy. There is a good agreement between the tested and the calculated inertial and bending force for all beams. The ratio of inertia force to the total impact load for the encased GFRP and encased steel beams to the reference beam is about 9% and 5%, respectively.

“…When glass is utilized as an aggregate, its high alkali content facilitates the formation of the pozzolanic reactions and the inclusion of glass powder has a positive effect on the properties of concrete [14]. Additive fibers can improve concrete responsiveness under static and dynamic loads [15]. The cementitious compositions of RPC cause brittle failure in tension or compression, therefore fiber reinforcement is added [16,17].…”

Section: Introductionmentioning

confidence: 99%

The Effect of Different Curing Methods on the Properties of Reactive Powder Concrete Reinforced with Various Fibers

Luti,

Abbas

2024

The current study explores the effects of four curing methods on the strength of Reactive Powder Concrete (RPC) reinforced with different fibers. Four mixtures of RPC, reference (RM-RPC), wavy fiber reinforced (WF-RPC), carbon fiber reinforced (CF-RPC), and micro steel fiber reinforced (MF-RPC) mixes were prepared and cured following four curing methods (normal, autogenous, coating, and warm water). The results revealed that warm water curing achieved the highest values of compressive, flexural, and splitting strength, attaining 138.9 MPa 22.4 MPa, and 20.89 MPa, respectively. The results of using different fiber reinforcement displayed that the compressive strength of fiber-reinforced RPC mixes was notably higher than that of the RM-RPC. The compressive strength increase results were 9.04% for WF-RPC, 24% for CF-RPC, and 27.96% for MF-RPC regardless of the curing method adopted. Flexural strength increased by 21.2%, 38.47%, and 55.86% for WF-RPC, CF-RPC, and MF-RPC, accordingly in autogenous curing, whereas the change in flexural strength was 30.65%, 39.14%, and 36.59%, correspondingly in coating curing and 21.27%, 29.22%, and 39.55%, respectively, for warm water curing. The optimum flexural values were mainly obtained for MF-RPC regardless of the kind of curing used. CF-RPC almost achieved the same results as MF-RPC with slightly lower values. It can be concluded that fiber reinforcement had a more positive influence on the flexural and splitting strength of RPC than on the compressive strength.