How to enhance the longevity of a concrete driveway with rebar

A concrete driveway should be strong enough to provide support to the cars and trucks which may drive over it. The concrete driveway should be constructed in such a manner so that the longevity of your house is enhanced.

Normally, the thickness of concrete driveway slabs remain 4 inches but the thickness can be 6 inches to give extra support for large trucks and other heavy vehicle traffic.

Preferably, the slab contains some type of reinforcement inside. One common building reinforcement material is rebar.

Rebar: Rebar is built up with steel and has been employed for more than 150 years to reinforce concrete construction. Concrete slabs are extremely susceptible to cracking, and rebar facilitates to control cracks from being expanded since sections of cracked slabs move apart.

Rebar verses Mesh: Welded wire mesh is a good substitute to rebar for driveway reinforcement. The mesh comprises of galvanized panels of welded wire. Heavy gauge welded wire mesh panels arrange reinforcement for driveways which are not regularly steered with heavy vehicles like construction vehicles or industrial trucks.

Mesh is generally applied by the contractors who pour 4 inches thick driveway concrete as it is a finer reinforcement and not very costly as compared to rebar.

To pour in a thicker driveway, number three rebar should be applied, that is 3/8 inches in diameter, for reinforcement.

Applying Rebar: Rebar will be very effective in a driveway for which 5-6 inches of concrete is poured. It is due to rebar is relatively thicker as compared to galvanized mesh reinforcement. In order to apply rebar reinforcement in a perfect way, make sure that it is placed in the center or marginally over the center of the slab's thickness.

For this purpose, concrete pros hold up the rebar grids on special metal or plastic supports, known as "chairs." The bricks and other scrap material can also be employed for supports, but it can produce weak spots in the slab. Rebar grids are built up by placing the pieces of bar in a perpendicular pattern, with equal span.

The bars are secured jointly at each intersection through metal wire. The edges of the grid should be retained at same gaps from all sides of the slab, and the minimum coverage of concrete should be retained all through the slab.



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Published By
Rajib Dey
www.constructioncost.co
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Some useful guidelines for repairing of concrete

The longevity of modern concrete is maintained for a prolonged period when the concrete is proportioned and arranged at the construction site in a perfect manner.

Besides, ageing of construction, there are other factors to influence the stability and reliability of the concrete construction which range from the impact of dreadful weather, cavitations, abrasion-erosion, corrosion of reinforcement, impacts of chemicals, carbonation, cracks, design and construction defects, etc. Under such circumstances, it is essential to repair concrete quickly as possible.

Given below, some useful tips for undertaking proper repairing work for concrete :-

1. Find out the reason for damage in concrete

It is the most vital step for concrete repairing. It is necessary to recognize the proper reasons of damage, and alleviate that reasons so that repair is maintained for long period otherwise the repair may weaken again under the similar reason, and leads to waste of effort and money.

It is required to recognize the action of freeze and thaw, cavitations, abrasion-erosion, structural overload or movement in the form of cracks or spalling of concrete.

In specific cases, it becomes difficult to determine the exact rasosn of the damage to concrete and for this purpose some tests like carbonation of concrete, the chemical attack on concrete, alkali-aggregates reaction in concrete etc are required. It is recommended to consult with experienced & authorized structural engineer or repair experts to conduct testing of concrete.

2. Estimate the Range of Damage in Concrete

Work out the range and intensity of damage i.e. how much concrete gets damaged as well as how this damage will impact the longevity of concrete in the future. Alternatively, also determine how much strength or load bearing capability are lost for concrete.

Concrete soundness test is considered as the most recognized and simple method to estimate the damage of concrete. Under this test, a hammer or large metal is used to the surface of the concrete. If the sound of the strike produces clear ringing sound, then the concrete is long-lasting, and if the sound remains hollow or dull, the concrete is considered as delaminated or unsecured concrete (weak concrete) and the repairing should be done instantly.

There various non-destructive tests to estimate the damage in concrete. Given below, the detailed lists of some crucial non-destructive tests to estimate the stability or damage of concrete.

• Rebound Hammer Test

• Ultrasonic Pulse Velocity Test

• Core Test

• Carbonation Test

• Chloride Content Test

It is recommended to undertake some maintenance works to recognize the damage of concrete at an initial phase. The proper and regular maintenance of the house minimizes the cost of repair, and ultimately saves money significantly.

Preparation Prior To Repairing of Concrete

Elimination of decayed or damaged concrete is crucial for undertaking a perfect repair. This step comprises of the cutting/chiselling of concrete in appropriate shape, elimination of loose concrete, steel cleaning and the coating of bonding agent on reinforcement steel, cleansing of the repair area, use of the bonding agent on the concrete surface (to create a exact bond among existing and new concrete), use of repair method, and curing of repaired surface.

4. Selection of Repair Materials and Methods of Repair

Repair materials and the repairing process should be chosen on the basis of the damage of concrete, size of repair work, the completion time of repair work, etc. Repair materials and repairing process should be arranged in much a manner that it will not speed up the damage of existing concrete or reinforcement steel.

5. Curing of Repair

The condition of the curing varies for different repairs materials. The manufacturers of repair materials always indicate the curing need of those specific materials in their material catalogue. Some materials need comprehensive water curing, whereas less curing is required for others. Some require protection devoid of water exposure unless they become hardened.

It should be remembered that, insufficient or inappropriate curing will weaken the performance of repair materials as well as the stability of repaired concrete/structure. Finally, the cost of rework of repairing will be raised significantly. Therefore, curing should be perfect once the repairing of concrete is completed.

To get the complete solution of the above problem, go through the following article gharpedia.com



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Published By
Rajib Dey
www.constructioncost.co
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Benefits and drawbacks of concrete driveway construction

Concrete driveway construction is more beneficial as compared to conventional driveway construction methods. The concrete driveway is long-lasting.

Given below, the pros and cons of concrete driveway construction.

Benefits of Concrete Driveway Construction - The prime benefits of concrete driveway construction are as follow:

1. Quality Construction
2. Stability
3. Extreme Flexibility
4. Less Maintenance
5. Costs
6. Diverse range of options

1. Quality Construction: The concrete as a driveway material improves the quality of appearance. It offers a clean and professional view.

2. Stability: A concrete driveway that is efficiently constructed and properly preserved can endure for prolonged times. As a robust structural material, concrete can bear heavy traffic loads, corrosion and even other atmospheric vulnerabilities. To ensure long-lasting integrity, the perfect plan should be made for the formation of concrete in terms of mix design and construction joints that is based on the conditions of the site.

3. Offers Extreme Flexibility: The concrete driveways are suitable for different types of landscaping designs, or building layouts. It is recognized for both residential and traffic use.

The use of concrete driveway only improves the beauty of the property. The flexibility is sustained in respect of concrete driveway installation and the design variety it provides.

4. Less Maintenance: Due to extreme stability of concrete driveway, the maintenance work is minimized significantly. Like other pavement options, various problems like weeds, paver shifting etc are not found in concrete driveways. There is little or zero maintenance for concrete driveway.

If any stain is found over the concrete, it can be easily eliminated. It is just necessary to cleanse the surface annually with the use of proper stain cleaner.

The sealants can also be applied in concrete driveway construction to safeguard the surface from stains and other damages.

5. Costs: Here the cost is associated with construction cost and maintenance cost. The initial cost of concrete driveway construction is cheap but it is adjusted with the zero-maintenance cost it offers.

A good concrete driveway constructed can sustain for 20 to 25 years with zero maintenance that yields huge savings in cost in due course of time.

6. Variety of Options: The concrete driveway construction comes with various types of design options. Either a slab look, or paver look (stamped concrete), or polished look (Polished concrete) can be arranged on the basis of the requirement.

Drawbacks of Concrete Driveway Construction - The following drawbacks are found in concrete driveway construction:

1. The application of polished or stamped concrete driveway construction is little bit expensive with regard to the normal concrete driveway construction. To maintain the longevity, special maintenance are essential for these types.

2. It is required to appoint professionals and skilled labors for pouring concrete to driveway construction. The process becomes very complicated when executed as a DIY project.

3. It is suggested to utilize sealants for annual Maintenance so that the concrete driveway slabs last for a long time.



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Published By
Rajib Dey
www.constructioncost.co
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Some vital methods for concrete curing

METHODS OF CURING :- Based on the type of construction work, the curing of concrete is done with the use of the following processes :-

1) COVERING: Under this method, wet gunny bags or hessian are utilized to wrap the newly developed concrete surface. This process is very effective for horizontal and vertical surface.

2) PONDING: Under this process, the entire surface is segregated into rectangular or square cages with the development of tiny clay bunds and these cages are filled with water occasionally building small ponds. This process is ideal for curing horizontal surfaces like floor, pavements etc.

3) SUBMERGING IN WATER: Pre-cast concrete members are over and over again cured by submerging them under water.

4) STEAM CURING: With this process, steam under pressure is sprinkled over the concrete surface. This process is very useful for pre-cast members.

5) SPRINKLING: Under this process, the water is sprinkled repeatedly over the concrete surface to keep the surface wet.

6) CURING WITH CHEMICAL: Under this process, water is sprayed over the surface as soon as specific amount of hygroscopic salt like NaCI, CaCletc are added. It helps to engross moisture from the atmosphere.

(7) MEMBRANE CURING: Under this process, concrete surface is wrapped with water proof membrane like wax emulsion, bitumen emulsion etc. The membrane stops the vaporization of water from concrete surface.

Article Source: www.civilnoteppt.com

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Published By

Rajib Dey

www.constructioncost.co

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