Reinforcement bond

Corrosion Resistant Fiber-Reinforced Plastic (FRP). Fiber glass reinforcement bonded with furfuryl alcohol thermosetting resias provides plastics with unique properties. Excellent resistance to corrosion and heat distortion coupled with low flame spread and low smoke emission are characteristics that make them valuable as laminating resins with fiber glass (75,76). Another valuable property of furan FRP is its strength at elevated temperature. Hand-layup, spray-up, and filament-win ding techniques are employed to produce an array of corrosion-resistant equipment, pipes, tanks, vats, ducts, scmbbers, stacks, and reaction vessels for industrial appHcations throughout the world. 

The stability of the concrete mix can be considered in terms of its cohesion , which is a subjective term used to describe its ability to maintain a homogeneous appearance when subjected to applied stress. Lack of cohesion leads to segregation of the mix components into layers relevant to their densities. A further term associated with mix stability is that of bleeding , which is the movement of water to the surface of the fresh concrete. This phenomenon can occur either in isolation or as a manifestation of segregation. Bleeding in excess is normally considered to be undesirable because of the dangers of water runs at the shutter/concrete interface and cracking due to plastic settlements, and there is also the possibility of adverse effect on the concrete-reinforcement bond due to the collection of water beneath the steel. 

Similar data have been obtained for other lignosulfonate-based water-reducing admixtures where cement and workability were kept constant with a reduction in the water-cement ratio and the reinforcement bond was measured by ASTM C234 91a, with the result shown in Table 1.29 [107]. 

Table 1.28 Effect of a lignosulfonate-based water-reducing agent on reinforcement bond under an appiied external voltage (after Kondo)...

Admixture Water-cement ratio Reinforcement bond ... 

A system composed of a series of layers (of polymer and reinforcement) bonded together. 

There is also a shortage of data on the impact of the transition zones both paste-aggregate and paste-reinforcement on concrete properties. The correlation between concrete durability and strength of bond has not been foimd as yet. Mindess et al. [54] propose some methods of paste with aggregate or reinforcement bond strengthening. The silica fume addition can be apphed very easily. 

Area of concrete cross-section, net of steel reinforcement Area of FRP reinforcement Area of FRP shear reinforcement Area of one stirrup leg Area of steel reinforcement Young s modulus of elasticity of concrete Young s modulus of elasticity of FRP reinforcement Young s modulus of elasticity of the fiber itself Young s modulus of elasticity of steel reinforcement Design value of the maximum anchorage force transferred by the FRP reinforcement bonded on a masomy structure in the presence of a force perpendicular to the bonded surface area Shear modulus of adhesive Shear modulus of concrete Moment of inertia of transformed section... 

Abstract To ensure better performance for a range of existing reinforced concrete structures in seismic regions with substandard structural details, seismic retrofit is an economical solution. Hence, this chapter presents some of the available results in which fiber-reinforced polymer (FRP) composites can be used for damage-controllable structures. For example, the performance of existing reinforced concrete structures whose components are vulnerable to shear failure, flexural-compression failure, joint reinforcement bond failure, or longitudinal reinforcement lap splice failure and retrofitted with FRPs is described. Novel concepts of modern constructions with controllability and recoverability using FRP composites are addressed. 

The modification of cement concretes and mortars by polymers and resins is aimed at improvement of their mechanical properties compressive and tensile strengths, matrix-reinforcement bond, impermeability, corrosion resistance, etc. There are three main groups of polymer modified concretes ... 

Figure 65 Schematic of a bonded stringer in the comet, (A) Stringer bonded to skin, (B) Reinforcement bonded to stringer, (C) Edge reinforcement bonded to skin.

Figure 66 Schematic of the bonded window surround in the comet, (D) Doubler bonded to skin, (E) Reinforcement bonded to skin, (F) Heavy outer skin, (G) Window frame.

DeVries, R. A., J. O.Jirsa, and T. Bashandy (1998), Effects of Transverse Reinforcement and Bonded Length on the Side-Blowout Capacity of Headed Reinforcement, Bond and Development Length of Reinforcement A Tribute to Peter Gergely, SP-180, R. Leon, ed., Ameriean Conerete Institute Farmington Hills, MI. 

In the past, many failures occurred cOTiceming mainly side effects due to invasive retrofitting interventions on the MHS ensembles. The current evolution in this field focuses on the development of compatible grouts, fiowable mortars, and repointing mortars for irreversible type consolidation of the mass of the masonry corpus. Besides, steel and other fiber reinforcement bonded on the surface of masonry with materials of polymeric- or cement-based matrix are used as reversible interventions. 

An improvement on RC ring beams are reinforced masonry ring beams, combining good quality brickwork (generally made of solid bricks) to steel or composite reinforcement bonded together by a binder-Uke grout (Ministero deri Beni Architettonici e Culturali, Italia, 2007). 

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