Human Development And The Evolution Of Its Constructions

Human development and the evolution of its constructions

Today the human being has developed certain skills for its existence in society which caused results such as the existence of constructions and mega constructions that surround the entire world and one of the most important materials that facilitate its construction is the concrete. 

With this you can develop large construction projects to improve the quality of life of all people. This material results in the construction of housing, bridges, highways, buildings among other various projects that are mainly based on the world of engineering. Concrete is a mixture of aggregate, cement, sand and water that when hydrating is a resistant construction material. Therefore, it is important to know the concrete materials for its production and application in the works. In the following lines the various inputs of concrete, types and mixing design for concrete will be announced.

There are supplies that facilitate the obtaining of concrete for this, cement, aggregate and water are combined. Askeland & Wright states that "cements are inorganic materials that apply and harden after being mixed to form a paste using water". Cement is a combination of clay and limestone agglomerant materials that later thanks to calcination and subjected to grinding we get the clinker and combined with the plaster we get in Cement Portland. Also, Askeland & Wright mentions that “thick aggregates are composed of gravel and stone.

They must be clean, resistant and durable. Aggregate particles that have a round angular shape provide resistance due to mechanical intertwining between them ”. The aggregates are materials that are used within the construction, it is called that because it is added to the cement plus water to form the concrete. Thus there are also different types of aggregates for their application that are: thick, fine, artificial and natural aggregates. They are also classified into three igneous, metamorphic and sedimentary groups. In addition, Askeland & Wright points out that “a high proportion of water-cement improves the ease of work of concrete, that is, the ease with which the concrete water grout or pasta can fill all spaces of a formwork generating resistance and durability and durability". Water is a liquid input that mainly helps to the concrete setting process, so it is very important to use drinking water for its application and combination with concrete. However, with the use of water as input of concrete that contains flavor or color, in most times satisfactory results are obtained in production.

Concrete, like other materials, develops high compression resistance, however, due to porosity and hardness it presents bad properties to tension. In order to obtain good results, several methods are used. According to Smith & Hashemi, in reinforced concrete or also known as reinforced concrete the tension forces are transferred from concrete to steel through their contact. The concrete that contains rod -shaped steel, wire, etc. It is known as the reinforced concrete since it contains the steel that fulfills the flexion at the time of the earthquake, while the concrete is highly hard and without its link with steel would not present feasible results during an earthquake. 

On the one hand, Smith & Hashemi, mentions that “the tension resistance of the reinforced concrete can improve if compression tensions are introduced into concrete. by pretensate or post -tensioned, using steel reinforcements called tensioners ”. As the prestressed concrete is mentioned, it is a method that is carried out before placing the concrete next to the steel, this process is specifically based on placing the tensioning steel and then placing the concrete which is called prefabricated material, this technique is used to overcome theconcrete weakness subject to traction efforts, the objective is. 

On the other hand, in the post -staging the armor tense once the concrete has acquired its optimal resistance in other words when the concrete setting process has already completed.

The mixing design is a process that consists in determining convenient amounts for its production of concrete, it must be carried out mainly in both fresh and hardened state. Correa emphasizes that “the mixture design of the concrete involves the determination of the most practical and economic combination of the ingredients of concrete’. From the aforementioned appointment it follows that to create a concrete with a desired resistance and durability, an ideal dosage must be taken into account that must be between the concrete components. Similarly, workability is a property ownership in a fresh state that results through test methods, it is the one that aims to determine what is the work used to overcome friction between the components of the concrete. 

In other words, workability becomes the ease of mixing, transporting, placement and compaction without segregation that becomes the separation of the individual thickness of the concrete phase with which its distribution and behavior ceases to be uniform and homogeneous. Likewise, to obtain the quality of concrete, a compression resistance is required for this, it is importantconcrete is not only based on having good materials but it is important to know the design of mixing, transport, emptying, compaction and cure. These processes will result in the good quality of concrete. If one of these processes is done poorly, a poor quality of the concrete will be obtained despite having exactly graduated the cement, concrete, sand and water. 

Finally, the economy is mainly based on the cost of ingredients of concrete, labor and equipment, for this the cost depends on the type and quality of the concrete produced. On the one hand, the variation of the budget of the materials due to the fact that the price of cement is greater than that of the aggregates since it intervenes as an important material in the construction. While the cost of aggregates is secondary. On the other hand, the cost of water has no influence this is clearly seen in some locations. An unchanging mixture with poor equipment increases labor cost. As a result in small works, concrete can be economical in quotes, but in large works of high volumes the concrete must present a good compaction design with quality control in order to improve costs and construction deficiency.

In conclusion, concrete is a mixture of aggregate, cement, sand and water that when hydrating is a resistant construction material which develops high compression resistance. There are also types of reinforced concrete, prescribed and post -tensile that are characterized as methods for obtaining good results. On the other hand, the mixture design is a process that consists in determining convenient amounts for its production of concrete these can be determined by trials, which would be the property of work and according to the quality of concrete without omitting the costwhich depends specifically on the type and quality of the concrete produced. Therefore, it is recommended to know the necessary materials and how to mix, transport, emptying, compaction and cured to obtain a good quality concrete. A good compaction design with quality control improves costs and deficiency.

BIBLIOGRAPHIC REFERENCE

• Askeland, d., & Wright, W. (2017). Materials Science and Engineering . (7th edition.). Mexico City, Mexico.
• Smith, w., & Hashemi, J. (2014). Fundamentals of Materials Science and Engineering. Mexico City, Mexico: ISBN: 978-0-07-352924-0.
• Salamanca, r. (2000). Portland cement application and added cements. Bogotá, Colombia: Science and Engineering Neogranadina, 10 (1), 1.