Advantages And Disadvantages Of Concrete Strengthening

In Figure 4, Young's modulus is plotted against yield strength. The diagonal line in the figure represents the material index M= σy/E. Materials below the diagonal line are the best candidate materials because they will remain elastic while providing the maximum conformability. All materials that cost more than $2.20 per pound and have a UV rating of "poor" were eliminated. Also, only materials that can be made through the polymer extrusion process were considered. The candidate materials are listed in Table 1 and ranked by the material index. The current material, TPV, is included in the table for

Another requirement is that buyers want are “longer design lives, longer inspection intervals, and shorter inspection downtimes” (Alderliesten, 2008). This causes many issues for aircraft designers since the primary materials were only aluminum and titanium for the past fifty years and this has not changed. Composites were the only answer for the problem because of the current uses of composites being used on aircraft. Composites materials are lighter than metal, resistance to corrosion, and production manufacturing is possible. One of the composites that are being used is carbon fiber-reinforced polymer composites (CFRP) due to the material properties being able to replace some Aluminum parts in aircraft structures. As the development process of aircraft to meet the requirements given by the industry, designers realized that some aspects of the aircraft couldn’t be changed due to stress and the environment effects the aircraft goes though during flight. A new structure was formed a composite/metal structure to be used where just a composite could not replace a metal. In 2012, Boeing created a revolutionary new plane, The Boeing 787 Dreamliner Commercial Airplane was the first plane to have most of the metals taken out of the plane structure and replaced by composite structures as seen in Figure 1

High compressive strengths are achieved by using a low water-to-cementations materials ratio, requiring the use of water-reducing admixtures to provide adequate workability. High strength concrete offers significant economic advantages over conventional normal strength concrete (NSC) because more slender members can be designed, resulting in reduced material and transportation costs. As structural components become more slender, deflection becomes a more crucial issue, making long-term creep and shrinkage deformations especially important in HSC structures.

Fly ash offers both environmental advantages and also improves the performance and quality of concrete. It affects the plastic properties of concrete by improving workability, reducing water demand, segregation and bleeding and lowers heat of hydration increases the strength, reduces permeability, reduces the corrosion of steel, increases sulphate resistance, and reduces alkali aggregate reaction. It reaches its maximum strength more slowly than concrete made with the port land cement. Also, Concrete is a relatively brittle material, when subjected to normal stresses and impact loads. The tensile strength of concrete is less due to widening of micro-cracks existing in concrete subjected to tensile stress. Due to presence of fiber, the micro-cracks are arrested. The introduction of fibers is generally taken as a solution to develop concrete in view of enhancing its flexural and tensile strength. Fiber reinforced concrete is a short discrete, uniformly dispersed and randomly oriented suitable fibrous material used to increase structural integrity. The amount of fibers added to concrete mix is measured as percentage of the total volume of composites. Aspect ratio (l/d) is calculated by dividing fiber length (l) by its diameter

Concrete is a multipurpose and durable of building materials which are most famous and widely used in the manufacturing world. High Performance Concrete (HPC) also named as a concrete mixture, which consists of high ultimate strength, high workability and high durability compared to the concrete produced with conventional method. American Concrete Institute (ACI) defined high-performance concrete as a concrete which meet all special combinations of performance and uniformity requirements that cannot always be achieved by using conventional constituents and normal mixing, placing, and curing practice. The high-performance concrete does not require specific ingredients or specific equipment except careful design and production.

Further, the pre-stressing technique has eradicated the weakness of concrete in tension obtaining crack free members of structure wherein the tensile zones are minimized and cracks are limited under permanent loads increasing the structural durability consequently. To cite an example, in a prefabricated concrete slab on the steel

But more than 80 developing countries in the world suffer from housing shortages resulting from population growth, internal migration etc. Most of the dwellings in rural areas are made of cheap local materials which are temporary and unsafe. Ferrocement is such a material that is slim and slender but at the same time strong and elegant which provides a potential solution to roofing problems [8]. The addition of fibers to the concrete enhances the strength properties of the composite and transforms the brittle cement composite into more isotropic and ductile material called FRC. But these two materials have some drawbacks. These two materials cannot be employed where high vibration, high tensile forces and high impact are to be resisted. Hence the solution lies in the new composite called fibrous ferrocement, which is the result of combining FRC and ferrocement. Fibrous ferrocement can overcome the limitations of both ferrocement and FRC to certain extent. Hence fibrous ferrocement can be employed where high impact, high vibration and high wear and tear are familiar [5]. In this unique material the advantages of both FRC and ferrocement are united. In fibrous ferrocement three types of reinforcement are used. The first type of reinforcement is welded mesh where smaller diameter bars are kept closely in both directions and are spot-welded. This mesh gives stability and shape to the structure. The second type of reinforcement

Miyazaki N and Hamao T, (1996). Effect of interfacial strength on erosion behavior of FRPs, J. Compos. Mater., 30: 35–50.

Concrete has low tensile strength therefore, it cracks under tensile load. But this can remove by reinforcement or prestressing.

Abstract— Concrete is a composite construction material composed of aggregate, cement and water. There are

2. Corner crushing mode (CC mode): In this mode the infill crushes in at least one of the loaded corners, as shown in Fig. 1.1-b. This failure shows frequently a clear diagonal strut mechanism with two clear parallel cracks (Behavior and analysis of masonry-infilled reinforced concrete frames subjected to lateral load). This failure is associated with masonry material of weak compressive strength. This mode is more likely to take place other than the rest of failure modes (Experimental and Analytical Seismic Evaluation of Concrete Masonry-Infilled Steel Frames Retrofitted using GFRP Laminates).

In this paper the non-conventional reinforcement details of beam-column joint has been discussed. The non-conventional details includes using inclined crossed bars in the joint, and it can be placed as additional bars or by bending the longitudinal column’s bars. This paper first discusses types of joints, collapse of structures due to beam-column joint failure, explores some experimental studies about this type of reinforcement detail, and then the main advantages of using diagonal bars in the beam-column joint. Using diagonal bars has significant advantages for the beam-column joint: increasing ductility, affecting the

The individual stresses on the C-clamp can be combined using the principle of superposition, which states that “the effect of several loads acting simultaneously is equal to the algebraic sum of the effects of each load acting individually.” By combining Equation (1) and Equation (3) we get an equation for stress under combined flexural and axial loading, seen in Equation (4).

FRP composites having superior material properties when compared with metals, improved corrosion resistance, fatigue resistance, less weight to strength ratio and high fracture toughness. Hence GFRP composites frequently used in several applications like sports goods, racing car bodies and aerospace components [1]. Often composite products manufactured by near-net shapes. The components made by secondary machining processes are involving to get good dimensional accuracy and

For the construction of the hull 2 materials were identified as possible choices namely FRP (Fiberglass Reinforced Plastic) and Alumunium Alloy. The advantages and disadvantages of each material will be investigated from the perspective of strength, durability, weight, maintenance and repair and cost.