Control Of Corrosion on Underwater Piles

Shubham Sunil Malu

Piles are structures used to transfer loads from superstructure to the sub surface strata. When the subsurface stratum is water based or if we deal with a hydraulic structure, the piles are to be driven into water and under water strata. Piles used in underwater structures are often subjected to corrosion. There is no absolute way to eliminate all corrosion; but corrosion protection measures are employed to control the effect of corrosion. Corrosion protection can be in different ways according to the environment and other factors. Forms of corrosion protection include the use of inhibitors, surface treatments, coatings and sealants, cathode protection and anode protection. The control measures explained in this are Protective coatings, cathode treatment and application of Fibre Reinforced Polymer (FRP) Composites.

Corrosion is the destruction of metals and alloys by the chemical reaction with the environment. During corrosion the metals are converted to metallic compounds at the surface and these compounds wears away as corrosion product. Hence corrosion may be regarded as the reverse process of extraction of metals from ore.

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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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Use of Ancient Titan’s For Development of New Suspension Bridge

Shubham Sunil Malu

Suspension means to suspend something as system of spring and shock absorbers which supports vehicles on its wheels and make it more comfortable to write. In likely suspended bridge is a bridge which is suspended from cables running between the towers. We have discussed here how the bridge works and the force accounted in the bridge due to various load acting on it like wind, water, moving vehicles.
Here we discus the construction sequence in suspension bridge & have discussed the disaster in Tacoma narrow bridge in detail.

“Suspension bridge is one where cables or ropes or chains are stung across the obstacle & the deck is suspended from these cables”

Anatomy of a Bridge

Deck –  For pedestrian, train, and / or automobile traffic.
Supports – The towers are the supports.
Span – Describes the distance between towers.
Foundations – The supports rest on the foundations.
Approaches – The approaches are the roads leading up to the bridge.
Long wire cables – are strung over the towers and secured to the anchors on land.
Hangers – run from the cables to the deck hold it up.

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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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