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16Jul 2017

Damac Maison de Ville Artesia, Dubailand

Construction Week Online|

http://www.constructionweekonline.com/article-45386-site-visit-damac-maison-de-ville-artesia-dubailand/2/

16Jul 2017

Grenfell highlights Gulf cladding time bomb

Arab News|

http://www.arabnews.com/node/1129886/business-economy

15Jul 2017

30,000 Residential Units Due for Delivery Till 2017 End in UAE

Dubai Chronicle|

30,000 Residential Units Due for Delivery Till 2017 End in UAE

13Jul 2017

UAE tenants enjoy rent-free months… how?

Khaleej Times|

http://www.khaleejtimes.com/business/real-estate/uae-tenants-enjoy-rent-free-months-how

13Jul 2017

Dubai’s second quarter property sales dim broker expectations

Gulf News, News|

http://gulfnews.com/business/property/dubai-s-second-quarter-property-sales-dim-broker-expectations-1.2058181

12Jul 2017

Spike in demand for Dubai’s ’emerging communities’

Gulf News, News|

http://gulfnews.com/business/property/spike-in-demand-for-dubai-s-emerging-communities-1.2057293

12Jul 2017

Market changes mean many Dubai landlords now offering monthly payment

Short List Dubai|

http://www.shortlistdubai.com/around-town/article/15107-dubai-landlords-now-offering-monthly-payment-plans

12Jul 2017

Dubai landlords accept monthly rent cheques as market changes

Arabian Business|

http://www.arabianbusiness.com/content/376071-dubai-landlords-accept-monthly-rents-as-housing-stock-rises

11Jul 2017

Low end of Dubai villa market drives transactions in 2017

Khaleej Times|

http://www.khaleejtimes.com/business/real-estate/low-end-of-dubai-villa-market-drives-transactions-in-2017

06Jul 2017

The creation of concrete

Big Project ME|

5th July, 2017

Mike Kenyon, partner and head of  Machinery and Business Assets at Cavendish Maxwell, discusses the details of concrete production.

At a first glance, the creation of concrete appears very simple; a mixture of cement, water and admixtures. However in reality, the batching of concrete is far more complex.

Creating concrete is knows as batching of concrete and is created by mass, opposed to the traditional way of by volume. Concrete is formed through the process of measuring ingredients by volume or mass and then mixing these ingredients together.

When creating concrete, the materials used consist of cement, water, aggregate and admixtures. A careful percentage of each should be combined using the below materials:

Cement:

There are many misconceptions as to what cement is, and if it is just the same as concrete. Portland cement however, is the basic ingredient of concrete and is a powder like substance that when mixed with water, turns into a thick formula.

So, what is in cement? Cement includes clay, slate, chalk, sand and limestone. When heated at a very high temperature, these ingredients form a substance which is rock-like. The rocks are then grounded down into powder which then becomes known as cement.

When making concrete, cement acts as the binding agent for the water, aggregate and admixtures.

As Featured In

Big Project July 2017

Aggregate:

Aggregate is made up of gravel, sand and crushed stone and strongly affects the quality of the final concrete. Aggregate can come in two forms, fine and course. Fine aggregate is the components in their simplest forms whereas in course aggregate, the components can range up to 1.5 inches in size.

If aiming for a high quality concrete, using less water in the mixture helps. Air bubbles can take up to 8-10% of the mixture so it is important to understand the requirement of the concrete so that this can be reduced if required. Surprisingly, cement typically makes up only 10-15% of the mix, with water at 15-20% and admixtures contributing a massive 60-75%.

Admixtures:
Admixtures reduce the need for large amounts of water in the mixture, increase the strength of the concrete and the workability of the cement mixture.
Chemical admixtures are used to give the concrete particular characteristics such as change the colour, ensure it doesn’t corrode around metal bars and reduce the amount of air bubbles.
Mineral admixtures however, are added to the concrete mix to improve its properties or stand in as a replacement for cement.

Water is combined with the mix to ensure it flows more freely. The more slump required in the concrete, the more water should be added and vice versa.

If aiming for a high quality concrete, using less water in the mixture helps. Air bubbles can take up to 8-10% of the mixture so it is important to understand the requirement of the concrete so that this can be reduced if required. Surprisingly, cement typically makes up only 10-15% of the mix, with water at 15-20% and admixtures contributing a massive 60-75%.

Water:

Each project, requires a different grade of concrete so it is custom designed to suit the projects needs. The planned use of the concrete helps the customer and concrete producer to determine the measurement of substances, strength of the mixture and the content of air in the mixture.

The mixing begins with some water before adding admixtures aggregate and cement into the mix.

Within the UAE, concrete is predominantly produced from concrete batching plants, which are in convenient areas for easy distribution to the main construction sites. The mix is then transferred into the truck mounted rotating mixer which we see on our roads daily.

The concrete mix should be used within a short amount of time from mixing to final use. It is usually recommended that the concrete should be deposited onto the job site within 90 minutes. This is to avoid losing the slump in the mixture.

Elsewhere around the world, mobile volumetric batching plants are now being used which can mix the ingredients on site. They are mounted on a lorry chassis and therefore can provide a smaller batch of concrete which can be custom made on site. This means that all ingredients (cement, water, aggregates and admixtures) are transported to the site where this mobile plant mixes it into concrete to be used there on site. At present, these types of batching plant are not used in the UAE as typically the number of units (villas or small tower blocks) are still too big to accommodate mobile plants. Building projects are usually so large in the UAE that they need a centralised batching plant to be able to produce the high quantity of concrete required.

At Cavendish Maxwell, we have the most experienced team of plant and machinery valuers in the UAE, who are able to advise on any valuation or disposable asset queries you may have.

Mike Kenyon is Partner and Head of Machinery and Business Assets at Cavendish Maxwell

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