Smart Concrete

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Smart Concrete

Concrete is the most widely used construction material because of its high compressive strength, relatively low cost etc. One adverse property of concrete is its sensitivity to crack formation as a consequence of its limited tensile strength.For that reason, concrete is mostly combined with steel reinforcement to carry the tensile loads. Although these rebars restrict the crack width, they are mostly not designed to completely prevent crack formation. Cracks endanger the durability of concrete structures as aggressive liquids and gasses may penetrate into the matrix along these cracks and cause damage. Consequently, cracks may grow wider and the reinforcement may be exposed to the environment. Once the reinforcement starts to corrode, total collapse of the structure may occur. Therefore, it seems obvious that inspection, maintenance and repair of concrete cracks are all indispensable. However, crack repair becomes difficult when cracks are not visible or accessible. Moreover, in Europe, costs related to repair works amount to half of the annual construction budget. In addition to the direct costs, also the indirect costs due to loss in productivity and occurrence of traffic jams carry a severe economic penalty. Accordingly, self-healing of cracked concrete would be highly beneficial. Self-healing is actually an old and well known phenomenon for concrete as it possesses some natural autogenous healing properties.However, autogenous healing is limited to small cracks, is only effective when water is available and is difficult to control. In 1969, self-healing properties were for the first time built-in inside polymeric materials.

 
 

Principle Of Smart Concrete

Concrete is a construction material that is used world-wide because of its first-rate properties. However, the drawback of this material is that it easily cracks due to its low tensile strength. It is a well-known fact that concrete structures are very susceptible to cracking which allows chemicals and water to enter and degrade the concrete, reducing the performance of the structure and also requires expensive maintenance in the form of repairs. In this paper, the following notable points regarding classification of bacteria, self-healing of cracks in concrete, chemical process for crack remediation, self-healing mechanism of bacteria, application of bacteria in construction field, Advantages and disadvantages of bacterial concrete etc., are observed and identified from the other research works. Cracking in the surface layer of concrete mainly reduces its durability, since cracks are responsible for the transport of liquids and gases that could potentially contain deleterious substances. On the other hand the concrete structures show some self-healing capacity, i.e. the ability to heal or seal freshly formed micro-cracks

Advantages:

  • Helpful in filling of cracks in concrete.
  • Helpful to reduce leakage of residential building.
  • Helps to reduce permeability in concrete.
  • Helpful to reduce corrosion of reinforced concrete.
  • It increases durability of concrete.

MATERIALS:

1.Cement –Ordinary Portland cement of grade 53 available in local market is used in the investigation. The cement used has been tested for various properties as per IS: 4031-1988 and found to be confirming to various specifications of IS: 12269-1987 having specific gravity of 3.0.

2.Coarse Aggregate –Crushed granite angular aggregate of size 20 mm nominal size from local source having specific gravity of 2.71 is used as coarse aggregate.

3.Fine Aggregate –Natural river sand having specific gravity of 2.60 and confirming to IS-383 zone II is used.

4.Water –Locally available portable water confirming to standards specified in IS 456-2000 is used.

5.Microorganisms –Any of the following bacteria may be used for the process:

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+98 21 44906869

Canada office phone

+1 (647) 402 7774

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info@dalahoobetonsaee.com

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Factory address

No 11/1, First Shavrivar Alley, Tavoon Blv, Asheri St, 11km Tehran-Karaj Highway, Tehran, Iran

Canada office address

509-7191 Yonge Street, Thornhill, Ontario, L3T 0C4, Canada

Copyright 2021 – Dalahoo Beton Saee company. All rights reserved.

Ten Tips For Concrete Management in the Heat

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10 Tips for Concrete Management in the Heat

 

When placing concrete in high temperatures, contractors must manage complications such as accelerated slump loss, plastic shrinkage cracking and faster set times.

 

 

A record-breaking heat wave is stretching across most of the United States this week, with about 195 million people under watches and warnings as temperatures peak today and into the weekend.

More than 85% of the lower 48 state’s population will see temperatures above 90 degrees Fahrenheit over the next few days, according to CNN meteorologist Dave Hennen , and more than half will see temperatures higher than 95 degrees.

But for those working outdoors, these extreme temperatures are unavoidable—the job still must get done. Besides the risk of experiencing symptoms of heat-related illnesses such as heat cramps, heat rash, heat exhaustion, fainting and heat stroke, concrete contractors also face numerous challenges when temps rise. Placing concrete in extreme weather means managing complications such as accelerated slump loss, plastic shrinkage cracking and faster set times.

To combat these issues, Kryton International offered in a recent blog post the following concrete management tips for working in hot weather:

1. Don’t let tight deadlines tempt you to order or try to place more ready-mixed concrete than you can finish and cover.

2. Make sure you have enough labor and equipment to place concrete quickly. Delays and prolonged agitation lead to higher concrete temperatures and slump loss.

3. Mixers, chutes, pump lines and other equipment in contact with the mix should be shaded, covered with wet burlap or painted white to reduce solar heat.

4. On windy days, install windbreaks.

5. Use refrigerated water, ice or liquid nitrogen to cool the mix during batching.

6. Consider beginning the job in the afternoon to capitalize on lower evening temperatures.

7. Ensure each ready-mix truck carries additional super plasticizer for temperature-related slump loss.

8. To protect against premature water loss, wet down substrates before pouring concrete.

9. Spray aggregate piles to keep them cool and damp.

10. Immediately following final finishing, begin the wet curing process, using specifications

Contact Info

Iran office phone

+98 21 44906869

Canada office phone

+1 (647) 402 7774

Email

info@dalahoobetonsaee.com

Iran office address

Ayatolah Kashani St., Sazman Barnameh North St., Tehran, Iran

Factory address

No 11/1, First Shavrivar Alley, Tavoon Blv, Asheri St, 11km Tehran-Karaj Highway, Tehran, Iran

Canada office address

509-7191 Yonge Street, Thornhill, Ontario, L3T 0C4, Canada

Copyright 2021 – Dalahoo Beton Saee company. All rights reserved.

Technology is Here to Stay

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Technology is Here to Stay

 

Concrete structure design is one of the subsets of structural design. The design of a concrete structure is different from the design of a steel structure. The design of conventional concrete structures has fewer challenges than the design of steel structures. Because zero to one hundred concrete structures can be designed with the same design software as Atbas, but in steel structures, issues such as fittings, etc. can not be designed with the help of software and requires sufficient experience and knowledge. . On the other hand, in many steel structures in the field of design of joints, according to the provisions of the tenth regulation of the national building regulations, it is very difficult to get the desired answer. Structural design of Shahverdi residential building is one of the concrete structural designs of the structural team. Due to the injection of step cost, today concrete structures are used more than steel structures, except for special cases, one of which is the lack of ground, which the employer is forced to use steel structures. Due to the higher strength of concrete structures in the same volume, steel structures usually result in smaller dimensions in a structure similar to a concrete structure, and this feature distinguishes steel structures from concrete structures and makes them more pleasing to architects. Be. Structural roof systems in the design of concrete structures are more diverse than steel structures. One of the advantages of concrete structures over steel structures is the problem of vibration. In steel structures, one of the concerns that can sometimes lead to an increase in the cross section of the side beams is the issue of vibration control. But there is no such problem in concrete structures. Today, due to market fluctuations, employers usually buy the desired rebar before designing their structure, which is one of the issues that usually causes operational problems and limitations in the design of concrete structures. Because it is difficult to control the distance of the rebars according to the available testers and the usual required limit. One of the important issues that the user must control in Atbas software is the issue of maximum allowable column reinforcements. Atbas software is based on the American Concrete Code (ACI), which limits the maximum percentage of reinforcement outside the patch area to 4 and in the patch area to 8. However, Article 9 of the National Building Code limits the maximum amount of reinforcement allowed outside the patch area to 3 and in the patch area to 6. Therefore, if the percentage of column reinforcement in Atbas is, for example, 3.5, that element does not show red, but the percentage of permitted reinforcement of that column is higher than the value provided in Section 9 of the National Building Regulations and the design of that column should be reconsidered.

 
 

The lateral bearing system of concrete structures is often in the form of a single bending frame or bending frame plus shear wall, which can be designed in medium or high ductility levels. An important point in the design of structures designed with shear walls is to control the stiffness of the floor diaphragm. In only flexural frame structures, it is usually easy to control the rigidity of the diaphragm. Due to the large dimensions of concrete structures, they usually do not have a problem in controlling the rise, but it should be noted that concrete structures suffer from long-term decline due to the creep phenomenon, the effect of which should be collected by the immediate rise of beams. Common roofs used for reinforced concrete structures are block beam roofs and concrete slab roofs, but in more specific structures, depending on the type of project and long openings, Cubiax and Ubot roofs have recently received more attention.

 
 

In more articles, the difference between the initial cost of steel and concrete structures was mentioned, but while the initial cost of steel structures is high, its execution time should also be mentioned. In relatively new roof systems in steel structures such as steel deck roofs, it is possible to concrete several roofs. However, in concrete structures, the progress of the skeleton is ceiling to ceiling. Therefore, execution time is one of the important factors in choosing the design of concrete structure or steel structure design. The structural team of Dr. Sarvar et al. Consulting engineers believe that according to the audited studies, the use of pins in the columns to restrain one of the rebars can not have the proper function. Therefore, in all drawings of concrete structures, in the design of columns, instead of using a pin, closed bends are used because studies show that closed bends have a more suitable seismic performance.

Contact Info

Iran office phone

+98 21 44906869

Canada office phone

+1 (647) 402 7774

Email

info@dalahoobetonsaee.com

Iran office address

Ayatolah Kashani St., Sazman Barnameh North St., Tehran, Iran

Factory address

No 11/1, First Shavrivar Alley, Tavoon Blv, Asheri St, 11km Tehran-Karaj Highway, Tehran, Iran

Canada office address

509-7191 Yonge Street, Thornhill, Ontario, L3T 0C4, Canada

Copyright 2021 – Dalahoo Beton Saee company. All rights reserved.