Self Healing Concrete

Shubham Sunil Malu

Self-healing materials are a class of smart materials that have the structurally incorporated ability to repair damage caused by mechanical usage over time. The inspiration comes from biological systems, which have the ability to heal after being wounded. Initiation of cracks and other types of damage on a microscopic level has been shown to change thermal, electrical, and acoustical properties, and eventually lead to whole scale failure of the material. Usually, cracks are mended by hand, which is unsatisfactory because cracks are often hard to detect. A material (polymers, ceramics, etc.) that can intrinsically correct damage caused by normal usage could lower production costs of a number of different industrial processes through longer part lifetime, reduction of inefficiency over time caused by degradation, as well as prevent costs incurred by material failure. For a material to be defined strictly as self-healing, it is necessary that the healing process occurs without human intervention. Some examples shown below, however, include healing polymers that require intervention to initiate the healing process.

A good way to enable multiple healing events is to use living (or unterminated chain-ends) polymerization catalysts. If the walls of the capsule are created too thick, they may not fracture when the crack approaches, but if they are too thin, they may rupture prematurely.

In order for this process to happen at room temperature, and for the reactants to remain in a monomeric state within the capsule, a catalyst is also imbedded into the thermoset. The catalyst lowers the energy barrier of the reaction and allows the monomer to polymerize without the addition of heat. The capsules (often made of wax) around the monomer and the catalyst are important maintain separation until the crack facilitates the reaction.

There are many challenges in designing this type of material. First, the reactivity of the catalyst must be maintained even after it is enclosed in wax. Additionally, the monomer must flow at a sufficient rate (have low enough viscosity) to cover the entire crack before it is polymerized, or full healing capacity will not be reached. Finally, the catalyst must quickly dissolve into monomer in order to react efficiently and prevent the crack from spreading further.

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Experimental Investigation on Concrete with Replacement of Coarse Aggregate by Demolished Building Waste with Crushed Concrete

Vijayvenkatesh Chandrasekaran
Student, Department of Civil Engineering, St. Josephs College of Engineering & Technology, India

Large quantities of construction and demolition wastes are continuing being generated which are just being dumped in the landfills. This requires large areas of land which is becoming difficult to find. The best solution would be to recycle and reuse the demolished waste which would not only help in protecting the environment but also help in dealing with construction wastes. Consequently, it have a grave difficulty to produce ecological toxic waste and in addition, obligatory a huge sum of liberty. That says about the project reuse waste crushed concrete maters (WCC) from the lath wastage of crushed concrete replacing from coarse aggregate 20%, 30%, 40% (WCC), 3% of crushed coarse aggregate (lathe waste) to reduce the generation of demolition wastes. (The analysis of demolished crushed concrete aggregate (DCCA) concrete in regular mold cast is to be ready in (7, 14, 28) days hydration and examination to be conduct lying on concrete. Such as compressive strength, split tensile strength, & flextural strength.) The replacing of coarse aggregate uses of waste mater and required strength attain in the conventional M20 grade concrete.

Keywords – Demolished Crushed Concrete Aggregate (DCCA), OPC (53 grade) cement, Lathe waste, Fine aggregate, coarse aggregate.

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Concept of Zero Energy Building

Aswin Kumar Das
Suvendu Parida
Subha Prakash Ratha
Phani Bhusan Panda
Bishnu Prasad Gariagadu
Diptimayee Sahu
Priyanka Sahu
Anubhab Panigrahi

Chapter- 1 Introduction
1.1. General:

Mahatma Gandhi envisioned a society where the man would live in harmony with nature. He Propounded having self-sufficient village communities to achieve this goal, having a civilization built on renewable resources. He insisted for the growth of human beings from every stratum of the society and to avoid wasteful use of resources. It is in the Indian culture system to find use for everything, which may be considered as waste by many. However in the race of rapid urbanization and globalization we have lost these practices leading to unsustainable growth of cities.

As per Figure 1.1, by 2008, 30% of Indian population was living in cities generating 58% of the total GDP of India. It is estimated that by 2030, more than 40% of Indians would be living in urban areas contributing to about 70% of the GDP. The cities are going to be the engines of growth for India to become a developed nation and so, the quality of life needs to be improved for sustaining the growth in the long term. India being the second most populated country in the world has some of the most densely populated cities in the world. The rise in Indian economy in the last couple of decades has created many job opportunities in the cities leading to a rapid influx of migrants from the rural areas to the urban areas.

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Understanding the Concept of Bubble Deck

Shubham Sunil Malu

As the infrastructure is developing there is need for some changes in the construction field, as one cannot rely on the same method for a long time as it can have different consequences. The main consequence is the shortage of material and manpower. Also, money matters a lot in construction department along with it the machines, equipment and technology in some region is not at a level, which we want. Hence in order to satisfy these results Bubble deck slab is one of the most effective slab techniques to replace conventional slab in terms of money and materials. Also, it requires less time to construct as compared to conventional slab.

Bubble Deck is a revolutionary method of virtually eliminating concrete from the middle of a floor slab not performing any structural function, thereby dramatically reducing structural dead weight. Bubble Deck is based on a new patented technique- the direct way of linking air and steel. Void formers in the middle of a flat slab eliminates 35% of a slabs self-weight removing constraints of high dead loads and short spans.

Incorporation of recycled plastic bubbles as void formers permits 50% longer spans between columns. Combination of this with a flat slab construction approach spanning in two directions – the slab is connected directly to insitu concrete columns without any beams -produces a wide range of cost and construction benefits including:-

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Artificial Recharge of Groundwater

Shubham Malu

The artificial recharge to ground water aims at augmentation of ground water reservoir by modifying the natural movement of surface water utilizing suitable civil construction techniques. Artificial recharge techniques normally address to following issues –

(i) To enhance the sustainable yield in areas where over-development has depleted the aquifer

(ii) Conservation and storage of excess surface water for future requirements, since these requirements often changes within a season or a period.

(iii) To improve the quality of existing ground water through dilution.

(iv) To remove bacteriological and other impurities from sewage and waste water so that water is suitable for re-use.

Thus, in most situation, artificial recharge projects not only serve as water conservation mechanism but also assist in overcoming problem associated with overdraft.The increasing demand for water has increased awareness towards the use of artificial recharge to augment ground water supplies. Stated simply, artificial recharge is a process by which excess surface-water is directed into the ground – either by spreading on the surface, by using recharge wells, or by altering natural conditions to increase infiltration – to replenish an aquifer. It refers to the movement of water through man-made systems from the surface of the earth to underground water-bearing strata where it may be stored for future use. Artificial recharge (sometimes called planned recharge) is a way to store water underground in times of water surplus to meet demand in times of shortage.
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