Benefits Of Reinforcing Concrete With Optical Fibre

Research Question and Problem Statement

Discuss about the Benefits of Reinforcing Concrete With Optical Fibre.

In the contemporary building and construction industry, there are two prevalent problems across the globe. One of the problems is the need to put the metropolitan land into maximum use due to land scarcity. This explains why in the current architectural developments, the traditional flat and small buildings are being replaced with the skyscrapers and high-rise buildings, particularly in the metropolitan regions of most countries globally. This move is propelled by the need for land economics owing to the rapidly growing urban population in most cities across the globe. The second problem is associated with erecting such tall buildings in clusters resulting in obstruction of the natural light from the sun. Essentially, the skyscrapers and high-rise buildings continue to face the challenge of illumination in their interior due to shielding of the sun’s light by the similar adjacent buildings. This challenge leads to high expenditure on the artificial sources of light such as fossil fuels and electricity in a bid to keep the rooms illuminated all the time. In order to overcome this challenge, the paper proposes the need to reinforce the ordinary building concrete with light-transmitting optical fibre to make the walls transparent or translucent thereby, allowing for the illumination of the interior regions of the buildings.

The research question for the study is “does the ordinary mortar-based concrete reinforced with light-transmitting optical fibre have more superior structural qualities for use in the building and construction industry?” Building and construction industry is one of the fastest growing sectors in the world today due to the rising demographics, especially in the urban dwellings and the growing demand for commercial buildings. However, due to the overcrowding of skyscrapers and storey buildings in the urban settings, direct sunlight does not make a way into into the interior of the buildings, leading to the need for artificial sources of light. It is therefore, important that the structural engineers take into account the need to illuminate the interior of the buildings sufficiently. This research undertakes to show that the problem of illumination of the commercial buildings can be eliminated by reinforcing the ordinary mortar-based concrete with light-transmitting optical fibres that allow for the penetration of light through the walls of the building.

Objective/Aim

The aim of the research is to find out the benefits of reinforcing ordinary mortar-based concrete with light-transmitting optical fibre

Study Hypothesis

Literature Review

The research hypothesis is “ordinary mortar-based concrete reinforced with light-transmitting optical fibre allows for the penetration of light through the walls”

The need to erect tall buildings within the central business districts of different urban settings continues to elicit mixed reaction within the building and construction sector. On one hand, architectural designers argue that high-rise buildings solve the problem of limited land available for expansion in the cosmopolitan settings.  On the other hand, city building and construction engineers have to battle with the challenge of room illumination arising from the obstruction of natural light from the sun by the similar adjacent premises. Owing to this, there is a need for coming up with transparent or translucent walls to help in the sufficient illumination of the interior regions of the crowded tall buildings.

Losonczi Aron, a Hungarian was the first architecture to develop the concept of light transmission through a concrete wall by reinforcing it with optical fibre (Sawant, Jugdar, & Sawant, 2014). His successful discovery led to the production of Litracon as a translucent wall two years later. Patil and Swapnal (2015) mention that the use of light-transmitting optical fibres in reinforcing the traditional concrete is reckoned as a great achievement in the building and construction since it is one of the highly valued sensor materials owing to its availability and extensive utilisation during the 1990s. On the contrary, Pathade, Nair, Tharwal, and Tiwarekar, (2016) cite that ordinary concrete can withstand strong compression forces compared to the reinforced. The authors, however, acknowledge that regular concrete reinforced with light-transmitting fibre has superior flexure and tension properties. One of the major drawbacks during the development of the idea was that the concrete did not display appreciable light sensing properties. However, with the evolution of building and construction technology, an up to date translucent construction material has been developed by introducing proportionate quantities of optical fibre material. It involves the drilling of mortar and cement to utilise the property of optical fibre as a light guiding material. Below is a picture of the reinforced concrete with optical fibre.

Kashiyani, Raina, Pitroda, and Shah (2013) cite that translucent concrete possesses high light-transmissive properties owing to its reinforcement with high-quality materials such as optical fibres as a building material. The authors argue that the stone within the concrete permits light to pass through it from one end to another, and this means that the fibres have to be integrated into the entire concrete structure. Many times the translucent concrete is called light-transmitting concrete owing to its optical capabilities. The translucent characteristic of the concrete composite can be realised in different ways; one is the use of a suitable bonding material. In such a case, the structural concrete is made by mixing it with clear resin to make it translucent. A ratio of about 4 to 5% by volume of the optical fibre materials is mixed with the mortar-based concrete. The secondary concrete developed has a comparably low weight as an advantage. The illustration is a composite of concrete made from optical fibre materials.

Li et al. (2012) and to Li et al. (2011) mention in their research that Light Transmitting Cement-Based Material (LTCM) as a building and construction material is modern concept that allows for  light propagation through its structure. In both the studies, the researchers incorporated a great amount of optical fibre material within the composite material block to allow for the passage of light from the illuminated region to the non-illuminated area. The authors report that LTCM depicted a high ratio of light diffusion along the direction of propagation of the light with appropriate optical fibre strands through a parallel arrangement. 

A concrete material capable of transmitting light through it is a composite made of optical fibre strands and fine concrete. According to Klassen (2006), the composite can be prepared as prefabricated building blocks or panels. Since the fibres are infinitesimal in size, they possess a unique ability of easily mixing with the fine concrete material to create an improved composite of material. The introduction of materials with a high numerical apertures like glass optical fibre with large diameters and Plastic Optical Fibres improves the quality of the material to transmit light efficaciously.  As Zhang and Liu (2008) observed, there is no sensible loss of light during transmission across the optical fibre material. This is because glass fibre materials possess the quality of guiding the light emitted by the points situated between the opposite ends of the panels. The data channelled by the light on the illuminated end of the building wall remains untampered with on the non-illuminated end because to their parallel position.  

Light transmitting concrete materials come in various forms such as the preassembled blocks or panels. According to Shanmugavadivu, Scinduja, Sarathivelan, and Shudesamithronn, 2014), one of the perfect examples is the Litracon room in which the objects found within the proximity of the light source appear as silhouettes upon illumination. Despite comprising only 4% of concrete, much of the light propagation through the optical fibre material is due to the parallel arrangement of the panels in a matrix form. Such panels or blocks also make it possible to develop load-bearing structures because the optical fibre materials do not affect the strength of the resultant concrete negatively. One of the commonest types of panels and blocks is the heat-isolation kind.  This variety is designed for people who do not prefer exposed concrete appearance.

Sathish and Suresh (2015) argue that it is imperative to substitute the ordinary mortar-based concrete with one that is reinforced with the optical fibre to improve its structural qualities. Such a technological necessity is informed by the fact that ordinary concrete is not strong under tension or flexure even though it is strong under compression. The resultant composite material can be generated by replacing the traditional aggregates of the mortar-based concrete with the translucent components. The translucent concrete material utilises the principle of nano-optics. In this principle, the optical fibre material allows much light to pass through by placing tiny slits on top of one another. This is because the optical fibre component of the resultant concrete composite acts as the infinitesimal slits through which light is propagated across the cross-sectional area of the composite. A number of layers of the glass optical fibres are stuck up together into a matrix profile, running run parallel to each other. The fibre strands are situated between the two major layers of each panel of the composite. The fibre strands integrate perfectly into the concrete structural component due to their infinitesimal sizes.

From the reviewed literature, the composite developed by reinforcing the ordinary cement-based concrete has unique properties that help in its utilization in the modern era of high-rise buildings in the urban settings of most of the countries across the world. The analysis is divided into structural, material components, and the strength of the resultant composite material.

The composite of the reinforced concrete is developed by mixing a specified proportion of fine concrete with 4 to 5% of the optical fibre materials of ideal sizes (Lee, Jeong and Park, 2009). In the structural design and development, the most important quality of the optical fibre material made use of is its ability to propagate light from both the natural like the sun and the common types of artificial light sources such electricity. This is enabled by the spaces found between the transparent concrete panels.  

The rationale for adopting optical fibre as a suitable component for reinforcing the ordinary concrete is its ability to propagate light at an incident angle greater than 60 degrees (Han et al., 2015). The fibre materials utilised in developing the composite are put in parallel. This allows them to propagate light between the two composite layers where they are put. In many scenarios, the width of the optical fibre material can undergo a certain degree of alteration of between 2 µm and 2 mm as the ideal range for the transmission of light. The optical fibre material possesses the quality of propagating light so competently that there is no sensible loss of the light due to absorption by the walls, and this explains its wide application in the production of the composite material. Besides, the optical fibre material ensures that there is the unaltered transmission of the various shades of colours through the composite wall. It is important to comprehend the structure of the optical fibre material used chosen as an ideal reinforcement material.

The compressive strength of the resultant composite material made by reinforcing the ordinary mortar-based concrete with optical fibre material oscillated between 20 and 23 N/mm² (Momin, Kadiranaikar, Jagirdar, and Ahemed, 2014).  This value indicates that the resultant concrete reinforced with optical fibre materials meet the specifications of the desired compressive strength for most of the structural construction, specifically the M20 grade (Drdlová et al., 2015). Momin, Kadiranaikar, Jagirdar, and Ahemed further argue that the light propagation of the resultant concrete reinforced with 7 to 10% the optical fibre strands  exude elevated transparency properties as opposed to the other alternative reinforcement materials like glass aggregates. As a result, this absolves the fact that light propagation does not have any impact on the compressive strength of the resultant composite material. In other essence, reinforcing the ordinary cement-based concrete with optical fibre material improves the strength of the resultant material. In addition, it significantly improves the aesthetical value or appearance of the material. 

The optical fibre material has a unique structure that makes it ideal for reinforcement of the ordinary concrete. It is essentially made up of three distinct layers as shown below. The ideal dimensions are as indicated in the diagram.

These layers are the core, the cladding, and the buffer coating, commonly referred as buffer jacket. When light is propagated from the source, is passes through the core layer of the optical fibre to the other parts by taking advantage of the optical properties of the material (Triantafillou & Matthys, 2013).  

In the modern structural engineering world, reinforced concrete continues to gain a wide application in fine architecture. In most of the cases where it is employed, is has been greatly employed as a suitable material for front elevation and cladding of the inner parts of the room. In addition, most structural engineers use the natural light from the sun for the illumination of the rooms, and this helps in economising the artificial sources of light such as electricity and fossil fuels.  Further, the building and construction engineers employ optical fibre as an aggregate for the development of the composite material in the detection of any prevalent or potential structural stress that may be experienced within the columns of the buildings. Other than stress detection, the engineers use the material to improve the aesthetic appearance of the erected columns.

Conclusion

In conclusion, the proposed structural reinforcement of the ordinary building concrete using light-transmitting optical fibre will solve the problem of poor illumination of the interior surfaces of the skyscrapers and commercial high-rise buildings erected within the metropolitan regions of most countries the world that occurs due to the obstruction of the natural light from the sun. One of the challenges of poor illumination of the tall buildings is the need for alternative costly sources of light such as electricity and fossil fuels. The problem of illumination of the rooms is eliminated by the fact that the light-transmitting optical fibres help in making the walls transparent or translucent. In addition, the proposed technology will greatly encourage the erection of tall structures in the metropolitan areas by eliminating the challenge of illumination of the rooms. This in turn will lead to the maximization of the scarce land available for the construction of structures for commercial use within the cities and towns.

Reference List

Drdlová, M., Buchar, J., Krátký, J. and R̆ídký, R., 2015. Blast resistance characteristics of concrete with different types of fibre reinforcement. Structural Concrete, 16(4), pp. 508-517.

Han, J., Lee, S., Kim, K. and Park, C., 2015. Tensile properties of glass/natural jute fibre-reinforced polymer bars for concrete reinforcement. IOP Conf. Ser.: Mater. Sci. Eng., 103,

Kashiyani, B.K., Raina, V., Pitroda, J. and Shah, B., 2013. A study on transparent concrete: a novel architectural material to explore construction sector. International Journal of Engineering and Innovative Technology, 2(8), pp. 83-87.

Klassen, F., 2006. Material Innovations: Transparent, Lightweight, and Malleable. Transportable Environments 3, p. 122.

Lee, C., Jeong, S. and Park, J., 2009. Use of fibre sheet strip stirrups for internal shear reinforcement of concrete beams. Magazine of Concrete Research, 61(9), pp. 731-743.

Li, Y., Xu, Z., Gu, Z. and Bao, Z., 2011. Preparation of Light Transmitting Cement-Based Material with Optical Fiber Embedded by the Means of Parallel Arrange. AMR, 391-392, pp. 677-682.

Li, Y., Xu, Z., Gu, Z. and Bao, Z., 2012. Research on the Light Transmitting Cement Mortar. AMR, 450-451, pp. 397-401.

Momin, A., Kadiranaikar, R., Jagirdar, V. and Ahemed, A., 2014. Study on Light Transmittance of Concrete Using Optical Fibers and Glass Rods”. InInternational Conference on Advances in Engineering & Technology (pp. 67-72).

Pathade, A., Nair, K., Tharwal, N. and Tiwarekar, R., 2016. Light Transmitting Concrete.

Patil Gaurao, S. and Patil Swapnal, V., 2015. Light Transmitting Concrete-A New Innovation.

Sathish, K.V. and Suresh, T., 2015. Study of Behaviour of Light Transmitting Concrete Using Optical Fibre. micron, 35(59), pp. 35-74.

Sawant, A.B., Jugdar, R.V. and Sawant, S.G., 2014. Light Transmitting Concrete by using Optical Fiber. Int. J. Invent. Eng. Sci, 3(1).

Shanmugavadivu, P.M., Scinduja, V., Sarathivelan, T. and Shudesamithronn, C.V., 2014. An Experimental study on light transmitting concrete. Intl. J of Research in Engg. and Technology.

Triantafillou, T. and Matthys, S., 2013. Fibre-reinforced polymer reinforcement enters fib Model Code 2010. Structural Concrete, 14(4), pp. 335-341.

Zhang, N. and Liu, R., 2008. A Reservation Protocols Based on Slotted ALOHA for Plastic Optical Fiber Network. In Advanced Computer Theory and Engineering, 2008. ICACTE’08. International Conference on (pp. 1040-1044). IEEE.