Los tecnicos que influyen para construir el edifio

Los tecnicos que participan en la construcción para construir el edificio son muchos, pero los principales son dos el Arquitecto y el Arquitecto técnico. El Arquitecto es el tecnico quien tiene cargo de hacer los planos del edificio, a quién le viene la idea del edificio. El Arquitecto técnico es el que tiene cargo de construir, es decir, todos los parametros que influyen durante la ejecución, es él quién tiene que resolverlos. Los dos técnicos asigna el promotor, la persona quién invierte dinero.

A continuación explicamos las funciones que ejercen:-

El Arquitecto

Es el proyectista, él quién hace los planos, quién prepara el plano básico y el plano de ejecución.

Durante la ejecución actua como Director de obra que lo que hace es va comprobando que la ejecución se realice según el proyecto.

El Arquitecto técnico

Es el personaje quién tiene función de llevar la ejecución, es decir todas las decisiones realizadas para la construcción del edificio las realizará él desempeñando como Director de ejecución de obra. También realiza el control de calidad y actua como Cordinador de Seguridad siendo Tecnico competente, eso quiere decir que este tecnico no solamente es Arquitecto técnico si no que también es Tecnico Competente en materia de seguridad e higiene.

Which technicians are requiered to build a building in Spain???

Generally to construct a building various professionals work together to get a building. The main technician is an architect who has to design planes, the other is a structural engineer who has to take the planes of architect and he calculates and designs a resistant structure. Then there is the building engineer or architecture engineer or technical architect who does the construction of a building, he has to create technical plans to construct the building.
The main technicians in Spain are an architect and technical architect. The architect designs the project and takes the charge as Project Director of the building. The technical architect takes the charge as execution work director who does the construction of the building.

The Project Director is the figure that involves in the construction of a building to construct it like it is projected in a plane.

The Executing Director finds ways to bring the idea of a designer into reality like he has to do everything that is necessary to do.

The other figure is the most common and everybody knows about it is the figure of the Project Manager. We can define that the project manager we can find in various processes of construction like we can find him in Construction company or the company which has done the calculation of the structure. As result this we can say the project manager in construction company has the charge to construct he has to do what the executive director and project director say, in other words, we can say he is the person who has to spend a lot of his time on the site. Whereas project manager in the process of a structure is another person from the company who has done the calculation.

Every technician has a lot of responsibility, however who has the most is technical architect (Building Engineer or Architecture Engineer, depending on country which you are) because execution is not too easy,  if in execution you do something wrong the element will get low resistance as a result of having incident in future caused by the element.

Characteristics of Fresh concrete

Homogeneity

At the time of manufacturing a concrete we have to mix a liquid with several solids of different nature and size. The mixture must be perfect and homogeneous, that means it shouldn't be separated particles of gravel on one side and particles of sand on other side.

We must care our concrete at the time of commissioning for having homogeneous mixture.

Plastic Retraction

The retraction is the decrese of volum that sufers the conglomerate in the fase of settle or first stage of hardness due to the evaporation of water.

The factors that could be included are:

• High doseof cement.(> retraction)
• High surface of the piece.( > retraction)
• The hot weather and dry air.( > retraction)
• Use of Admixtures to reduce the contraction.( < retraction)
• Prevent the reduction of water by curing well. (< retraction)

Docility

This is join properties to facilitate commissioning for fresh mixture, with the measures of proper compactation.

The docility depends on:

• Cement:- Increses with high quantity and fineness.
• Aggregates:- Fine aggregate incresses docility.
• Water:- High quantity of water will give more docility.
• Admixtures:- You could have it with them by using appropriate admixtures.

Setting and hardening of the cement

It knows that setting is transformation of plastic cement to solid cement.

It is exothermic cement that means detaches high quantity of hot.

Hardening is a progressive and slow acquisition of resistance over time.

The cement when it is settled it composed essentually of tobermorite with other minor compounds.

The Tobermorite is the compound which gives durability, hardness and resistance.

There are different variables which change characteristics of settled cement:

• Temperature of kneading water.

          Own temperature of cement or Temperature of kneading water affects the settiling of cement.If            there is Hot water it will settle quickly.

• Enviromental temperature 

          If there is cold, it will settle slowly.

• Grinding cement fineness

          If cement contains fine particles, it will settle quickly.

So this is all stuff that involves in the process of settle and hardness.

Types of cement portland

Actually , there are five types of cement CEM I, CEM II, CEM III, CEM IV and CEM V but I am going to explain you first three one because only these we use in building construction.

CEM I(Portland cement)

This type we can't use it in summer because it has too much hydration heat, therefore we only have to use it in winter. Additionally , We shouldn't use it where we have high risk of sulfate.

Uses

• Suitable for highly resistant concrete.
• For fabrication of concrete elements.
• for special public works in pre-stressed concrete.

Not recomendable to use for:

• Water and Grounds works and agressive enviroment.

Denomination 

• It has three classes of resistance(32,5-42,5-52,5).
• On the packet of cement you could also see alphabet "N" and "L"

               N:- Means that the initial resistance is normal.
               R:- Means that it has high initial resistance, thus the hydration heat is high.
Example

                                                                CEM I 32.5 N
CEM I :- Portland cement
32.5 :-  Resistance
N :- Normal hydration heat

Portland cement of resistant class 32.5 and normal initial strength

CEM II(Potland cement with additions)

This type is little bit difficult to explain because it classifies with different additions, those have different characteristics.

It is classified with six types of additions.

This type definies with "A" and "B".

A means that it has more clinker than B as a result of having more hydration heat.

1-Blast Furnace Slag(S)

Not used for:

• Pre-stressed concrete.
• Concreting in frost time

Examples:

CEM II/A-S 32.5 N

CEM II/B-S 42.5 R

The first one has more hydration than second one.

2-Silica fume(D)

It gives resistance to the concrete.

In spain this type doesn't comercialize because they doesn't make it.

It only classifies with "A".

Example:

CEM II/A-D 32.5 R

3-Pozzolana(P/Q)

"P" is natural pozzolana and "C" is calcined pozzolana.

It develops resistance in short and long period. It is not used for concrete for stripping and demolding.Continually, I will show some examples to understand it better.

CEM II/A-P 42.5 R

CEM II/B-Q 52.5 N

4-Fly ash(V/W)

"V" is  called siliceous fly ash and "W" limestone.So we don't operate it when we use for concrete that's gonna use to make pre-stressed prefabricated pieces and for stripping and demolding concrete.

There are various varieties of cement but what we should consider is we have to know why we use them and which are the affects that can be appeared.For that, we don't have to learn each word about cement.

Fly ash benefits us with several things, as it profits us by reducing expansive capacity of aggregate-alkalis, incresing strenght against sulfates and providing long-term capacity by reducting the initial potencial.

CEM II/A-V 32.5 R

CEM II/B-W 42.5 N

5-Calcined Shale(T)

This category we can't find it in Spain becuse it is not comercialized and fabricate. 

CEM II/B-T 52.5 R

6-Limestone(L/LL)

It is practised for having workability and improving compacity that benefits the resistance and the durability of a conglomerate. It's shouldn't be used for prestressed concrete and prefabricated prestressed structural elements .

CEM II/A-L 52.5 N

Every cement can be used masonry mortar but with low resistance clase llike 32.5. Normally on the site it used CEM II/A "o" B-L 32.5 N because it provides workability and durability with crumb sand that's gives plasticity provided that it has clay with more than of quantity.

CEM III

It classifies with three different percentage of clinker A, B and C. It also has resistance class "L" that means low initial strength, only in this category we are going to find it. We can't use it for prestressed concrete and prefabricated elements of concrete.

Cement of high hidration as a result of having C3S and C3A.

 CEM III/C 52.5 L

So this is what every Building Engineer should know, these are main three categories. If you know enough you won't get problems in the future.