SOME USEFUL TIPS TO ENHANCE THE CONCRETE STRENGTH
The construction is a vital constituent that can be applied for producing sustainable construction. Concrete is long-lasting, low maintenance, and has good resistance capacity against wind, water, and fire. The concrete can maintain heat and as a result it enhances the energy efficiency of buildings and reduces heating/cooling bills. The concrete is gaining popularity for the following reasons :• • • • • • • • • •
It provides lowest carbon footprint for a structure or pavement over its life cycle. It has unparalleled strength, stability, endurance, and resilience. It can increase energy efficiency through thermal mass. It retains sturdiness in any environment. It is a strong building material that doesn’t burn, rust or rot. It is versatile material as it can be molded into any shape, color or pattern feasible. No off-gas It has outstanding vibration and sound insulating. It offers low maintenance costs. It is 100 % recyclable.
The longevity of concrete is destroyed due to water since it transfers chemical contaminants into the concrete and as a result the surface can be decayed, the steel reinforcement is corroded. Besides, it leads to expansive and disruptive reactions and more. Given below, some useful recommendations to enhance the strength of your concrete project:
Mix Design Stability is maintained with a concrete mix design that is appropriately matched to the service conditions that the concrete is susceptible to. No single mix design is long-lasting in every situation. As for instance, if concrete is susceptible to sulfate contaminated soil, it is recommended to utilize the sulfate resistant cement in mix design. However, this mix design is improper in case a concrete structure is subjected to the cycles of freezing and thawing in a wet environment. Under this circumstance, the mix design should contain an air-entraining admixture as entrained air can safeguard the concrete easily.
Construction Joints The water can easily enter into the structures through construction joints. As a result the structure is damaged significantly by creating corrosion of the reinforcing steel. Ensure to design the structure with sufficient, predetermined control joint locations to get rid of random cracking. Ensure that each joint is protected with a safe waterproofing system of its own. A joint waterproofing system with crystalline technology can give durable protection at joint locations. The crystalline technology comes with self-seal random cracking and thus provide extra reliability and protection.
Low Permeability The water should be moved away from the concrete structure. The permeability can be reduced via good mix proportioning as well as lowering the amount of free water in your mix with water-reducing admixtures or plasticizers. A proper waterproofing system should be provided in concrete that is susceptible to water. A crystalline waterproofing admixture like Kryton’s Krystol Internal Membrane is considered as most useful to keep concrete safe from water penetration.
Proper Curing Proper curing plays an important role to retain the longevity of concrete. Curing means retaining the conditions so that the concrete is solidified easily and attain optimal strength. Other two vital factors are exact temperature and humidity. The temperature should remain over 10°C for gaining strength to move ahead at a reasonable speed. Moisture should be retained, especially in the first few days to start cement hydration and maintain the concrete from drying, shrinking and cracking. When the concrete is cured properly, the permeability is decreased, the strength & longevity is enhanced.
Concrete Placement The placing of concrete should be accurate. The workability and consistency of the concrete mix should be adequate to place and solidify the concrete into a solid mass that does not contain any voids or rock pockets. Voids generally found under or behind reinforcing steel bars – specifically in areas where several bars exist together. So, it is recommended to maintain exact vibration practices. Ensure to correctly vibrate all concrete with special attention around congested reinforcement. Rock pockets are areas where insufficient cement paste and fine aggregate exist to close the space among large aggregate. Ensure there is no standing water before placing concrete and do not move a concrete large distance from where it is poured in the beginning. The self-consolidating concrete should be used to get rid of these issues.
Reinforcing Concrete A concrete pour should be reinforced with rebar or steel mesh. Rebar can be added for strengthening the pour. In vertical or horizontal projects, lots of rebar should exist in the concrete to make the structure stronger. The ideal way for installing rebar is on 2-foot centers i.e. every 2 feet, a rebar bar should be placed. To gain more strength, double the number of bars. After that, increase the level of rebar in a flat pour to set the steel in the center of the wet concrete, rather than lying at the bottom. To make the slab stronger, the rebar should be provided in the middle of the wet concrete when it sets. The rebar chairs should be applied while placing the rebar to keep it a couple of inches off the sand base.
While pouring concrete, check the weather. The hydration rate of wet concrete, the rate at which the concrete sets, is influenced by several factors. On a scorching sunny day with little or no humidity, concrete may set at a rapid rate, resulting in shrinkage and a feeble structure. Check the concrete from the truck and add more water unless the consistency becomes perfect. Now, it is required to mist new concrete with a water hose every hour on the day it is poured, and no less than three times a day for the next two days. The slower the curing, the concrete becomes stronger. By wetting the external of the concrete throughout the curing process over a period of three days, the concrete produces a strong internal bond. While ordering concrete, check that the calcium is not included to your concrete on a cool day. Calcium is a common additive, that is provided to the wet concrete when the truck is loaded to allow a quicker drying time in cold weather. It can accelerate the process of the pour but it also reduces the strength of the concrete as it promotes air filtration in the wet concrete. Lastly, vibrate the wet concrete. Vibrating facilitates the wet concrete to filter into voids in hard-toreach places, like the space under a basement window. Besides, it eliminates tiny bubbles from the wet concrete to transform the final product more solid. A pencil vibrator should be used while pouring walls.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ To get more informative civil engineering article, tutorials and videos; visit my website
http://www.constructionnews.co.in/ Like my facebook page https://www.facebook.com/sketchup3dconstruction