Aluminium Formwork for High Rise Buildings

Now a day’s Aluminium formworks used to construction for High Rise Buildings. Probably the most versatile modern construction system, aluminium formwork system, which has created new benchmarks in construction.  This produces a lightweight panel with an excellent stiffness to weight ratio, yielding minimal deflections under concrete loading. Once erected, these panels are subjected to a trial erection in order to eliminate any dimensional or on-site problems.

 Aluminium formwork  High Rise Buildings video 

Aluminium formwork can be used reused  more times  with careful handling and good maintenance. One of the biggest advantage of aluminium formworks has its unsur- passed construction speed. Compared to conventional construction procedures, use of aluminium formworks reduces floor completion cycle from 15 days to 4 to 5 days, primarily because of light weight nature enables fast erection and dismantling and simple system of pin & wedge makes the assembly easier. Pouring concrete together for walls, beams and floors and System ensures accuracy of dimensions without need for re-work and uncomplicated system  requiring use of minimum skilled labour.

But, over and above its strong advantages of speed, economy, re-usages and no extra cost, Aluminium Formworks give your construction structure a very high quality finish. High quality finish is possible due to uniformity of panels and precise joints, as it leaves no deflection, creating evenness, eventually adding style and stability.

Industrial Building Floor Construction

Industrial Building Floor Construction

Generally concrete slabs are used for industrial constructions.  They can be used below a layer of flooring material or are exposed; slabs on grade provide foundation for all building foundations. 

Also generally super-flat industrial floors are installed with laser-guided screeds and power trowels.  Quality material combined with good design and expert workmanship only yield the best concrete slabs.

Importantly the slabs are supported on the intermediate rolled steel joists.  The intermediate rolled steel joists are supported on columns spacing into two or more panels.

Floors in heavy engineering factories, workshops and garages should be resistant to impact, abrasion and attack by lubricating oils. The epoxy resin floor topping is suitable for heavy industrial floors. 

The extent to which the floors will be subjected to heavy wear and impact will often vary widely in different parts and since the more important type of finishes are more expensive it is advisable to ascertain as far as possible, before laying the finishes, where trucking gangways or process involving impact will be located and to provide accordingly.

Steel or cast iron tiles or plates, embedded in granolithic concrete may be used for areas of heavy abrasion by steel-tyred trucks or where a high resistance to impact is required. Granolithic concrete with suitable materials and good workmanship will provide in light industrial workshops and garages a floor finish of reasonable durability.

Special aggregates and metallic floor hardeners may be added to the granolithic concrete where heavy impact and wear is expected. Your factory will be invariably having a loading and unloading platforms. The requirements of the floor of loading and unloading platforms and industrial loading bays are primarily high resistance to impact and abrasion and non-slipperiness. Steel tiles or ‘anchor-plates’ or metal grids embedded in granolithic concrete are suitable for loading and unloading platforms subjected to heavy impact.

Industrial Building Systems

Industrial Building Systems are those structures used by an industry; this can be of any type ranging from salt and sand to those manufacturing of heavy equipment.   Generally at least a part and in most cases the entire area is of one storey height.  These buildings offer column free support and there lengths can vary largely, also these types of buildings provide thousands of usable square feet for manufacturing needs thereby offering the most cost effective solution in the market today.

Also these buildings are fully customizable with a variety of ceiling lights, windows, insulation and doors.   The speed of erection, high strength to weight ratio and ease of extension make steel the most popular industrial building material. Types of Industrial Buildings These industrial buildings can be classified in different ways, given below are two major ways of classification:

• Normal type building systems
• Special type building systems.

 

Also normal usage identifies, normal type building systems as the shed type building systems which is a rather rough construction used basically for storage purposes.  Also popular are the open frame structures that mainly consist of a structure supported by a skeleton made of steel or reinforced concrete rather than by load-bearing walls.  They often have diagonal bracing or shear walls and diaphragms for lateral stability; the strength of steel only makes it possible to have buildings with longer spans

A wide variety of building types exists, ranging from major structures, such as power stations and process plants, to small manufacturing units for high quality goods.

The most common type is the simple rectangular structure, typically single-storey, which provides a weatherproof and environmentally comfortable space for carrying out manufacturing or for storage. First cost is always an overriding consideration, but within a reasonable budget a building of good appearance with moderate maintenance requirements can be achieved. While ease of extension and flexibility are desirable, first cost usually limits the provisions which can be usefully included in the design for these potential requirements. Although suitable provisions can achieve savings in the cost of specific future modifications, for example by avoiding, the use of special gable frames, changes in manufacturing processes or building use may vary the modifications required.

Master builder

Dampness in Buildings Causes

Dampness is the presence of hygroscopic moisture in the buildings. Ground water contains soluble salts, the most significant of which are chlorides, nitrates and sulphates. When dampness occurs, these pass with the water up the wall and are left behind when the water evaporates. Over many years of active dampness, large quantities of these salts accumulate within the masonry and decorative surface,

 most becoming concentrated in a general 'salt band'. Both chlorides and nitrates are usually hygroscopic, (i.e. they can absorb moisture from the surrounding environment) and, in general, the greater the amount of salts the greater the absorption of moisture - especially under humid conditions. 

 It leads to unhygienic conditions affecting badly the health and comfort of the inhabitants and deteriorating the buildings. Protection against dampness should form an essential feature for any type of construction.
Sources of Dampness
The sources which create dampness in buildings are 

a.    Geological and climatic conditions

• Rain penetration
• Ground moisture rise
• Condensation in buildings due to moisture in the atmosphere
• Drainage of the site
• Orientation of the buildings

b. Structural causes

• Water used during construction
• Defective construction

Effects of Dampness: 

Dampness tends to cause secondary damage to a building. The unwanted moisture enables the growth of various fungi in wood, causing rot. Plaster and paint deteriorate and wallpaper loosens. Stains, from the water, salts and from mould, mar surfaces. Floor coverings loose their bond with floor bases. 

Externally, mortar may crumble and salt stains may appear on the walls. Steel and iron fasteners rust. Electrical installations get damaged. It may also cause respiratory illness to the occupants. In extreme cases, mortar or plaster may fall away from the affected wall. 

Dampness in buildings can generally be divided into three main catagories, each caused by a different phenominum. The categories are rising damp, penetrating damp and condensation. 
Dampness is a major source of disrepair in a building and can be caused by several factors such as 

• Leaking pipes or overflows
• Rain seeping through the roof, spilling from a blocked gutter, seeping in around windows
• Rising damp due to a defective damp proof course or missing damp proof course
• Condensation where moisture in the air condenses onto cold surfaces

Site Investigations

The type of foundation to be adopted for a building depends upon the load to be transmitted and the bearing capacity of the soil. When the site with a good bearing capacity of reasonable depth is available it is not difficult to design on the type of foundation. On the other hand on certain soil a close investigation is necessary soils of low bearing capacity of bearing depends. Costal areas where the upper stratum is sand and water level is high are cases where investigation is necessary.

 For a large building project such a multi-story structure the site exploration may be both extensive and costly and may include on of the following

1. Trial pits
2. Bore holes
3. Load test

  Trial Pit

A pit dug to a depth on type of foundation expected usually going up to about 3m and rarely to 6m. The pit should be large enough accommodate. A trial pit does exposes a section through the ground revealing for examinations the character and depth of stratum. Sample of soil for caboratory  testing can be readily obtain. A pit also gives the contractor valuable data regarding the cost of excavation of foundations such as foundation. Whether timbering is necessary and whether pumping of underground water is necessary for a building covering a large area four trail pits may be required one near each corners. These pits should not be dug too close to be the proposed building as they would be a source of weakness to the foundation it should be fill with concrete.

Bore hole    

As much work is involve in digging trail pits a simpler method is the use of bore holes. These are used for raising samples of soil for examination. A simple tool for mating bore hole is the Augur which may be operated manually or mechanically.

Load Test

In this method a weight of known cross sectional area dropped from known height. The depth of impression on the soil by the drop of the weight is noted for performing this experiment a pit of the required depth is excavated.

  The depth of pit will be equal to depth of the foundation. After excavating the pit is cleaned and leveled but should not be computed.

The concrete cube block is them drop very gently without impact from the specified height and the impression is noted down. The experiment is repeated at  last 5 times in different pits or along the foundation trench at different poles and the average depth of impression noted. The bearing capacity is worked out as follows.

           Let R is equal to resistance of soil that is resistance to the penetration or resistance to settlement.

H – height through which the weight is dropped

W – weight

D – depth of impression

A – Area of cross section of the weight.

High-Rise Buildings.

The most prominent tall buildings are called high-rise buildings.In the last twenty years the development the of  high-rise buildings in the world has been very fast.


The reinforced concrete structure is very popular for high- rise buildings. But in recent years, steel structure has been used more and more, especially in super high-rise buildings.


Two kinds of cladding materials are being used in high-rise buildings. The one is metal curtain-wall and other is masonry wall. The masonry walls, like clay brick and concrete structural bricks, are lower in price and easy in construction. Therefore, they have been used widely, especially in high-rise residential buildings. The metal curtain-wall is usually used for office buildings.


High-rise building is defined as a building 35 meters or greater in height, which is divided at regular intervals into occupiable levels. To be considered a high-rise building a structure must be based on solid ground, and fabricated along its full height through deliberate processes.


High-rise buildings also can be classified into several functional categories based on their use. The high-rise buildings are identify into the following categories.
      *   Residential
      *   Commercial
      *   Mixed
      *   Institutional 


High-rise buildings are constructed largely because they can create a lot of real estate out of a fairly small piece of land. Because of the availability of global technology and the growing demand for real estate, skyscrapers are seen as the most fitting solution to any city that is spatially challenged and can`t comfortably house its inhabitants. And hence, may be it is rightly said that `When you compare the population in our cities with the amount of land we have, the only way to provide better living conditions is by building higher.


There are thee main forms of  high-rise buildings construction are out line below.
Non- Continuous columns with continuous beams.
Continuous multistory column and beam
Cross-wall construction

Modern building construction

Modern building envelopes do not `breathe` like their counterparts of the past. In the 1940s, it took 30 weeks and 2,400 hours of on-site labour to build a house. The average size for a new home was 800 square feet. Four decades later, construction time dropped to 8 weeks with only 800 on-site hours, while the average size had grown to 1,230 square feet. Not only is the change implied on the time phase but instead has re-shaped the entire building industry. The truth certainly is that new homes are better built, better designed, and use better materials, products and systems than ever before.

Today`s professional builders understand building science and know how to build a home that not only looks good, but is also well constructed and great to live in. Today`s new homes are bright and comfortable all year-round, safe on energy costs and have good indoor air quality and take full advantage of the many advances in building products, materials and systems. And to top it off, a new home is carefully crafted with attention to the details-both what you can see and what you cant. Builders use a variety of efficient construction technologies to achieve unparalleled quality and performance.

Other most important changes that has occurred during the past several decades is that the home building process has been steadily moving away from the building site. At one time, homes were built entirely from scratch, with the builder and the construction team personally fabricating everything on-site.

Today, an entire industry is dedicated to pre-manufacture building components from floor joists and roof trusses to kitchen cabinets and interior trim. The components are made in factories to precise specifications and then shipped to building sites where trained building crews install them. The benefits of using pre-manufactured components are numerous. These materials and products are manufactured under strict quality control and conform to national standards. That means easier installation and fewer rejects.

It also means consistent quality and performance for homeowners. Furthermore, prefabricated components can be brought in as they are needed and installed immediately. This eliminates lengthy on-site storage and potential damage from rain, snow and sun. A well-trained and diverse labor force has further reduced construction time. Today, building is a team effort involving more than 30 trades (or 109 people on average) with specialized expertise. The builder is at the center of the entire process, managing the team and working with customers to ensure quality and satisfaction at every step of the way. Also the construction fraternity has almost broken the shackles of being listed as unskilled class thanks to vocational degrees on construction management. Further Automated tools have also increased efficiency on the construction site.

Now as per the genre of the modern construction the building works are classified in the categories mentioned beneath.

* Low-rise buildings
* High-rise buildings
* Long span buildings

Branningan's Building Construction for the Fire Service

Importance of waterproofing

The waterproofing should be made mandatory for all structures and should not an optional one. The approach to waterproofing problem must be conceptual and the selection of appropriate material and proper diagnosis of the problem and employing the right applicator for executing the job is equally important. 

waterproofing  is as important as any other parameter involved in designing a structure. It is because waterproofing also plays a vital role towards the durability concrete as well as the safety o the structure. Waterproofing can be executed at the
two stages of the construction


1.During construction, the integral waterproofing compound either in powder or liquid form can be
introduced in concrete to improve the waterproofing characters by optimizing the water
cement ratio. This will also helps to an extent to improve the flowability of the concrete.


2.The external surface of the concrete can be treated with appropriate waterproofing coating system to ensure the structure is made absolutely impermeable.


The durability of the concrete not only depends on its strength but also on the permeability of the concrete. Therefore waterproofing of concrete structures assumes greater importance and also it is imperative that the proper waterproofing is done. Actually when water enters the concrete undesirable pollutants like chlorides and sulphates gains entry along with the same resulting in carbonation. The first victim is embedded steel which starts to corrode
which leads to spalling of protective cover. And at this stage if there is no care taken it leads to the failure of the structure itself.Therefore in order to avoid such problems it is advisable to do proper waterproofing treatment. Now with the advent of latest technology polymer based waterproofing coating systems which is easier and effective to achieve waterproofing properties

Painting

There are many advantage of painting. Paint preserves, protects and decorates surfaces and enables them to be easily, that is why iron and wood are always painted. Advantages of painting are as follows:
1. It protects iron and wood from wear and tear and moisture. Beside this, it reduce the possibility of fire. Wood swells when it comes in contract with moisture. If wood is paited nicely,it is not affected by moisture.
2. Paint protects iron from rusting and corrosion.
3. Painted surface is clean, smooth and beautiful.
4. Reflection of heat and light takes place nicely on painted surface.


Adequate preparation of the surface to be painted is essential for success. The surface should be smooth, clean, dry and stable. The paint film is built up with more than one coat, e.g. a priming coat , undercoat and a finishing coat. The selection of a suitable type of each of these coats depends on the material of the surface and its location. Each coat must be dry , hard and rubbed down with fine abrasive paper before the next coat is applied.


Priming coat. This is the first layer of paint. It must suit the background and adhere to it and it must be compatible with subsequent layers. A primer may also have to satisfy one or more of the following requirement:
1. To penetrate porous surface (e.g. wood and plaster).
2. To inhabit corrosion (e.g. on ferrous metals).
3. To seal chemically active surfaces (e.g. on new lime plaster and cement) and thereby prevent them from disrupting subsequent layers of paints.
4. To be heat resistant.


Undercoats. These obscure the primer, bond it to subsequent coat and built up an adequately thick paint ; they must be of a suitable tint match the final coat.


Finishing coat. This gives the desired color and finish to the surface. Colours are innumerable and finishes very from flat to eggshell to oil-gloss to enamel. Gloss paits are more durable for walls, as unlike gloss paints, it does not emphasizes slight irregularities. Textured paintfinfsh can be obtained with special paints.
Type of paints. There are many bgroups of paints.
1. Oil paints.
2. Synthetic paints.
3. Water paints.
4. Emulsion paints.
5. Cellulose paints.
6. Varnishes.
7. Special paints.

Roof Waterproofing

Waterproofing of Roof be it concrete, metal decks, timber, etc. has always been a challenge to the construction industry. With the increased complexity of structures and the complex nature of utilization of this roofs, terraces or podiums and with possibility of structural move- ments and growing concern on leakages in the structures has created a need for a simple reliable roof waterproofing system.


Roof Waterproofing Demands:
* A system which can allow to take the movements in structure.


* A system that can allow itself to carry heavy intense built-ups such as - landscaping or gardens or ballast / pavers etc.


* A system robust enough to take pedestrian / vehicular traffic


* A system that can used to refurbish roofs without disturbing or breaking off the existing substrate


* A system that can be left exposed to atmosphere.


* A UV stable system


* A system with reliability and aesthetics.


* A system that demands to be laid loose or unbonded to the substrate.


* Long-life expectancy and maintenance free or minimal maintenance.


* A complete water-tightness


Prevailing Roof Waterproofing Practices & Viewpoint:
* Rigid waterproofing barriers: A conventional practice of rigid waterproofing such as brick-bat koba and crystalline waterproofing has limitation if structure is design to undergo movements during life span.


* Flexible & elastomeric waterproofing membranes: This type of waterproofing forms a membranous barrier against water leakage


They are as follows:
a] They come in form of liquids, either single component or multi-component, applied wit hand or spray. They could be cementitious polymer modified or acrylic or P.U. based or bituminous or epoxy based.


b]They come in form of preformed membranes either made up of modified bituminous membranes (APP, SBS), PVC, TPO, HDPE, EPDMs etc. they are either torch applied, stuck with adhesive, mechanically fixed.


Rigid waterproofing barriers have shown limitation or failure when subjected to certain aggressive conditions or structural movements during its life span. Bituminous / cementitious polymer modified EPDM membranes / HDPE based systems do enable elongations but have limiting success, application difficulties and deteriorate with time in
limited life span of application.


The reasons of failure of systems are many, it could be wrong system application or the behaviour & limitations of the material itself in terms of adhesion or UV stability etc. Over a period of time excellent development for different types of water proofing materials and system have been taking place, keeping in mind the criteria or requirements for a good engineered & reliable Roof Waterproofing System.

Grillage foundation

This is dependable foundation and is used in those place where the load of the structure is pretty and bearing capacity of soil comparatively poor. The grillage foundation helps in distributing the load over a wider area of subsoil. The grillage foundation helps in avoiding deep excavations as the necessary base area is provided for the load of transmission.

This type of foundation generally used for heavy structure columns piers and stanchions etc. the grillage foundation generally consist of steelI I section (R.S.J) laid in single or double larges. The second larger . The number of R.S.J.S and their distanced a part depend upon the load of the structure and the bearing capacity of the soil.

To construct a grillage foundation a trench of the required width and depth is excavated. The surface the trench is leveled and rammed. Over the rammed surface a layer of cement concrete is spread and is well compacted so as to make if impervious. R.S.J.S are of desired dimensions are laid at regular intervals. The lower flanges of the R.S.J.S are embedded in to the concrete by pouring rich cement mortar the R.S.J.S are connected together by pipes and bolts. The bolts are driven in to web of the R.S.J.S .

G.I. pipe pieces are placed between R.S.J.S and a long bolt is pass through all the holes and pipes. This will connect the R.S.J.S together there by forming a rigid mass.

Object of Foundation

Object of Foundation
As started earlier, the foundation is the device of transmitting the load of the whole structure to the sub-soil beneath it. However the following are the objects of providing foundation.
1. The aim of foundation is to distribute the load of the structure over a large area or to transmit the load to the board base of soil below it.

2. To load the bearing surfaces (that means sub-soil)at a uniform rate that is to distribute the load uniformly.

3. To prevent the lateral escape or movement of the To provide a leveled and from base over which super. Super can be constructed.

4. supporting material. For example If a structure is to be constructed on a sandy soil the supporting material that is the sand will have to tendency to slip now to prevent the movement or slipping of the supporting material. The foundations are constructed.

5. to increase the overall stability of the structure by preventing its

6. tilting or over turning against wind, earthquake and uneven distribution of live load from the above explanation it must be now clear as to by foundation are provided. Now the question arises as to by the foundations are generally carried below the ground level. The reason is quit obvious.

Roofing: Natural Lighting

Roofing: Natural Lighting

Daylight Design Daylight is a vital natural resource that will significantly improve the environment within any building. Rooflights provide three times more light than the same area of vertical glazing. They can also provide a much more even distribution of light, particularly in larger structures. Where vertical glazing exists, the effective area for natural lighting will only be within 6m of the wall containing the window. 


These facts are well understood by most people involved in building design. However the huge potential of rooflights to provide exactly the amount, type and distribution of natural light required to meet any given specification is not always appreciated. Rooflights can help to provide natural light with qualities appropriate to the use of the building.


Benefits of Natural Daylight : Daylight is an essential natural asset. For those of us living in temperate Northern climates, the beneficial effect of sunlight is easy to recognise; a couple of sunny days seem to lift everyone's spirits. Research also shows that suicide rates are considerably higher in parts of the world where daylight is very limited for significant parts of the year. On a slightly less dramatic but equally significant level, there is also a growing body of evidence to suggest that buildings enjoying high levels of natural light are literally more successful than those more reliant on artificial light. In all environments the eye and brain functions respond better to natural light, so people perform better, while passive solar gain can reduce energy costs.

Dam Proofing

Dam Proofing
In a building the structure should be free from dampness. A dam building is in healthy to these who lived in side and it causes damage to the building of the building there are various courses of dampness in the walls.
1. Moisture rising up in to the found a tin from the ground.
2. Rain beating against the walls which ay a absorb the Crain water.
3. A absorption of water from damage rain water pipes.
4. To prevent the water rising up the walls. From the foundations a special water proof layer is provided continuously on the top of the found tin. This layer is known as a horizontal dam proofing used in our country are 20mm thick cement, send rendering 112 and two coats of “bitumen” and coarse sand applied on the cement mortar bed some of o the materials used to form the horizontal dip asphalt bitumen/tar
Lead
Copper
Plastic.
M sot of these materials are very expensive in other countries in very dump soil for the DPC let and copper sheets are laid on 3 “thick cement concrete layers. The position of the horizontal dam proof course sold be atlas t loom a bode the ground level.

And if should be at least 50mm below the co west part of any wood member fixed to the wall
Eg;- feet of the door frame.

To preen rain H2 o passing from the top of walls, horizontal dam proof cares should be provided in immediately below the top course. Of the brick work with the walls are cohere a with roof to prevent this cause of dampness. The roof must be maintain properly.