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A step by step Roman concrete production process

If you burn the pieces of limestone on high heat, the stone sequentially release water and carbon dioxide forming carbon dioxide acid, as the temperature rise. At about 900°C, limestone represents anhydrous product of calcium oxide – white pieces of quicklime. This is the first conversion of limestone.

You should be very careful with these white stones as quicklime can eat away your hands, clothes and shoes. It ‘eats’ everything like sulfuric acid. If a pile of lime stones is watered it will hiss and boil, and bulges will rise above it. White pieces of lime quickly turn into a fine powder. A minute later the boiling stops. Thus lime is transformed in the so-called ‘hydrated lime’.

Dry hydrate is a dry powder to the touch. Poured on quicklime water got bound with it and the second transformation of limestone took place.

When you mix lime powder with water it won’t boil, but it will turn into dough with the technical name of the calcium hydroxide. The more water added to it, the more liquid it becomes. If the dough is tightly closed on top with soil, it will not harden for decades and still becomes very ductile. If the dough is left in the air, it will soon be covered with a hard crust and gradually turn into stone. Batter is the third conversion of limestone. It is almost ready to glue. The word ‘almost’ means that such dough can not be good to glue the bricks or stones as pure lime putty quickly dries and cracks. To avoid this, you need to have the dough mixed with sand. This mixture is called mortar and mortar transition into the solid stone – the fourth and fifth steps of limestone conversion. This is the most important and difficult stage of lime hardening.

A transition of mortar or concrete in a stone-limestone or calcium carbonate is known as hardening of the carbonate of lime binders. At ordinary temperatures it is made up of two simultaneous processes: evaporation of water from the lime paste (fourth conversion), with the gradual formation of a crystalline skeleton of calcium hydroxide (fifth conversion).

The process of crystallisation of calcium hydroxide is very slow. Evaporation of water causes gradual crystallisation and coalescence of its smallest particles into larger ones and. Growing crystals are fused together, forming limestone skeleton that surrounds the particles of sand. These two processes take place almost simultaneously and tested intensively for the presence of moisture and carbon dioxide.

The film of calcium carbonate formed during the initial period of hardening of the solution on its surface, impedes ingress of carbon dioxide into the inner layers of calcium hydroxide. As a result of the carbonisation process it is almost suspended and the hardening of the stone is mainly due to crystallisation, where necessary reduced humidity and positive temperature.

As a result of the formation of crystalline aggregates the strength of mortar air lime is very weak, and only after 28 days the hardening of 0.5 MPa is formed. Of course, the technical conditions no longer fit the concept of modern construction – these processes are speeded up and the companies like Telling, a largest UK construction agency widely applying hydraulic lime and lime mortar solutions, take advantage of artificial speeding methods. Back to the process, the resulting compound is not stable to water and frost. However, as a result of the ongoing process of carbonation, the strength of the mortar and concrete is increased by 5-7 times or more, but the process is very slow – for tens and hundreds of years.

Thanks to a new ultrasound method, material defects can now be displayed in three dimensions.

Ultrasound Application In Air Purification

Ultrasound is used in a wide array of non-standard treatment cases based on other physical principles of action. Such manufacturers like Hilsonic provide an opportunity of building custom ultrasound solutions and ultrasonic cleaner equipment in particular, allowing businesses and governmental organisations solve the most sophisticated tasks.

One of the major technical problems of today is the purification of polluted air from dust, smoke, fumes, mists, metal oxides, and so on. The smallest particles of matter from factory chimneys factory direct upwards, and then carried by wind over long distances. For example, the gray-fly on the leaves of trees and on surrounding objects is the sign of a cement plant somewhere around. Thousands of tons of cement plants exhale the smallest particles sputtered during firing. The same thing happens on the chemical, alabaster, gas and other enterprises.

So is this this problem solvable? For a long time technologists have been using the dust collecting units, which operation is based on different principles, consisting of dust chamber, rotary dust collectors, centrifugal separators, electrostatic precipitators, and so on. However, all these devices are cumbersome and not always effective enough. Therefore, scientists continue to look for new ways to speed up and improve the quality of air purification and gas pollution. Since 1967 symposium in Poland, scientists are working on reducing air pollution. Some scholars are noting in their reports promising ultrasonic method of air purification, due to an extensive set of noteworthy features. It does not depend on the temperature and humidity environment and can be easily automated as ultrasonic devices are totally easy to use. Continue reading


The Installation Of Cranes With Two Supportive Mechanisms

Gantry cranes are typically used at open space warehouses, mainly for general cargo, containers and timber, for installation of prefabricated industrial and civil buildings, maintenance of hydropower plants and partial assembly in shipbuilding. They are produced mainly with hoists or with special lifting devices. General purpose crane spans are usually 4-40 m; in serving shipbuilding stocks up to 170 m. The capacity of these cranes is 3-50 tons and for maintenance of hydropower plants and the stocks reaches 400-800 m (in some cases 1,600 tons – two trolleys of 800 tons). Capacity for small as a trolley used for self-propelled electric hoists. For the installation of large items (such as shipbuilding) cranes with two trolleys are used, allowing the load to turn over weight. The manufacturing of this equipment is conducted by medium and large businesses, focusing on custom and serial equipment manufacturing, such as Granada Material Handling, a far-famed gantry hoist and overhead crane manufacturer, servicing both UK and EU markets.

Installation of cranes with a two supports

A common requirement for the installation of gantry cranes is to the ensure minimum labor intensity and cost. Gantry cranes with a two legs are usually constructed with pillars hinged to the bridge. This allows you to tap by tightening self-lifting grounds rack mounting tackles. Previously, cranes with with lifting capacity of 5 – 12.5 m performed this operation without the use of other mechanisms: the running trolley supplied cable reel devices, allowing for the period of installation to connect the drum to the drive.

Recently, these drums are provided only in cranes designed for construction works (frequent relocation). Sometimes pulley cage assembly is mounted on racks, but mainly limited device lugs to connect them. For the tightening pulley winches or other tractors are used. Continue reading


Content Marketing For Newbies: Making The Right First Steps

Corporate blogging is an integral part of content marketing strategy to attract customers. The presence of the company’s blog gives such obvious benefits as increased traffic and leads generation. Through a blog, a company can create the image of an expert and promote relationships with its partners. But sooner or later the question arises: what sort of content should a business focus on? Where should I get ideas for new publications? Take advantage of a few tips by marketing experts – HTP Digital, a successful Manchester-based company focusing on b2b digital marketing and online promotion.

Make use of ‘How to’ articles

These materials contain practical information to help solve a specific problem of user or share some knowledge. Typically, these articles are highly appreciated by visitors if it is something fresh and truly helpful. Your scope may include the following aspects:

  • training video posted on the channel YouTube;
  • the organization of the contest by the decision of a problem with the award winner;
  • series of articles on a particular topic;
  • FAQs with answers to frequently asked questions;
  • checklists: Review the necessary tools and resources to solve a particular problem;
  • advice in the form of cribs: how to do things faster, better and easier.
  • reviews and ratings

Reviews of various niche products, and educational materials collections and reviews are not only a great way to attract visitors to the site, but also a nice strategy to gain new customers.

If you are reviewing books give a fair assessment of the book that will stimulate your review and other visitors, partner with industry experts to give more trust to your reviews.

Studies and surveys: start a primal A/B testing or implement a large, and then publish the results and their interpretation.

Advice: advise, with the help of some tools can solve this or that problem, and compare popular products.

Reports and studies: any useful piece of information can become very popular in its niche.

Interviews can take many forms: written, audio or video format with experts in your field or related areas, the potential audience may be interested in. In addition, you can invite an expert to write the publication of your blog in the format of a guest article.

Cover use cases

Gather use cases directly or indirectly related to your products or services, thus you will be able to achieve greater trust from customers through forming its image expert. Use one of the methods for creating successful use cases:

  • cover the problem which you had to solve;
  • share practical advice on how you worked to resolve the problem;
  • recommend tools and resources that you use;
  • show the successful solution of the problem, which was on the case.

Recent niche news

Regular publication of news about the events in your industry will not give the desired effect. Of course, the published information must reflect the interests and needs of the audience, so: comment, express your opinion about the events; summarise the week, preparing summary of the most important and interesting news of the week; write about large-scale events, choosing those that are really interesting; share your thoughts and predictions regarding the trends and future of the industry.