Lesson 4 - Building Superstructure

Engineered Formwork

- This is an evolved type of formwork that is made from prefabricated modules with metal frames, typically steel or aluminum. - Compared with traditional timber formwork, this type of formwork is much faster to construct (using pins, clips, and screws) and is considerably cheaper because it can be reused thousands of times before it needs to be replaced.

Permanent Insulated Formwork

- This is one of the most advanced formwork systems. It may also include thermal, acoustic, fire-resistance and rodent-resistance properties.

Traditional Timber Formwork

- This type of formwork is made from timber and plywood. While it is easy to produce, it has a short lifespan, and the process is time-consuming so it's not suitable for large structures. - is extremely flexible and is ideal to use in complicated sections of construction.

Re-usable Plastic Formwork

- This type of formwork uses interlocking and modular systems that are used to build highly variable but simple structures. - Using extremely lightweight and robust panels, this formwork is particularly suitable for similar structure projects such as mass housing schemes.

Load Bearing Walls

- It is carrying loads imposed on it, including its own weight, from above beams and slabs, and transferred to the foundation. These walls support structural elements such as beams, columns, and walls above. It can be an exterior wall or an interior wall. From the roof, it braces to the floor.

Formworks

- It is the term used for the process of creating a temporary mould into which concrete is poured and formed. - the traditional is fabricated using timber, but it can also be constructed from steel, glass fiber reinforced plastics and other materials.

Formworks

- It must be capable of carrying all dead and live weights other than its own weight. - A mold such as scaffolding, shuttering, falsework, or open-box containers in which fresh concrete is poured and compacted.

Concrete; hydration

- It solidifies and hardens after mixing with water and placement due to a chemical process known as __________. - binds other building materials together.

boom

- Pumping the concrete is one aspect of the overall task. Another is controlling where the concrete is placed. Whilst this can be done by manually positioning the end hose, a remote-controlled articulated placing ___________ is often used to position the placing hose exactly where the concrete is needed. The robotic arm is designed to unfold is a small area and be able to reach every spot within the length of the _________. Even if there are difficult barriers and constraints in the area. The pipe runs the length of the boom and a placing hose on the end can be positioned to place the concrete precisely where it is needed, quickly and easily.

Stationary or Static Pump

- The advantage is that the pipeline can be long so that the actual pump can be very far away from where the concrete is being placed; maybe hundreds of meters below or even kilometers away. - essential for tunnelling work and high-rise constructions. - come in a far greater range of capacity than those used on Mobile pumps. From smaller pumps ideal for residential and low rise work right up to the SP8800 which can reach pressures up to 243 bar and pump over 100m³ per hour. It is a middle of the range SP4000 which holds the World Record for pumping concrete to the highest vertical distance. (The job also included a horizontal component of over 1km.) A pumping distance has yet to be found which cannot be done by a Schwing pump.

Deformed Steel Bars

- have ribs, lugs and indentation on the surface of the bar, which reduces the major problem that is faced by mild steel bar due to slippage and good bonding is achieved between concrete and rebar. - The tensile properties is higher compared to other rebars. These bars are produced in sections from 6 mm to 50 mm dia.

Self-Erecting Tower Cranes (SETC)

- is a Tower Crane that can be easily inserted on a site with restricted space in a short period of time. - These cranes operate from a fixed position and must be safely placed on site by qualified field engineers familiar with the mechanisms that they are using.

Direct (or Chute) Discharge

- is a long metal trough with rounded bottom and open ends used for conveying concrete to a lower elevation. -

Polythene Sheets

- sheets are sued to cover the concrete slabs and columns. The sheet can be placed on the slab just after it gets hardened.

Formwork

- temporary structure which is used as a mould to pour the concrete. - It is a vertical or horizontal arrangement made to keep concrete in position until it gains strength and shape.

Trestle Scaffolding

- the working platform is supported on movable tripods or ladders. This is generally used for work inside the room, such as paintings, repairs etc., up to a height of 5m.

Cantilever Scaffolding

- type of scaffolding in which the standards are supported on series of needles and these needles are taken out through holes in the wall. This is called single frame type scaffolding. In the other type needles are strutted inside the floors through the openings and this is called independent or double frame type scaffolding.

Timber Formwork

- well-seasoned, light in weight, easily workable with nails without splitting, free from loose knots

Racking

- when the trolley moves the load horizontally along the jib without changing its level—is a function unique to this type of tower crane

Suspended Scaffolding

- working platform is suspended from roofs with the help of wire ropes or chains etc., it can be raised or lowered to our required level. This type of scaffolding is used for repair works, pointing, paintings etc.

- Sieve analyses of fine and coarse aggregates. - Unit weight (dry rodded density) of coarse aggregate. - Bulk specific gravities and absorptions or moisture content of aggregates. - Mixing-water requirements of concrete developed from experience with available aggregates. - Specific gravities of Portland cement and other cementitious materials, if used. - Relationships between strength and water-cement ratio or ratio of water-to-cement plus other cementitious materials, for available combinations of cements, other cementitious materials if considered, and aggregates.

ACI Method of Concrete Mix Design (6) *read only

Outer Walls

provide a shelter for the house, while inner walls help to divide the enclosure into the required number of rooms.

Rope and Pulley

suitable for lifting rough surfaces and heavy loads. For this purpose, the chains and wire ropes are used. The alloy chains are best suited for hoisting operation. The weakest component of this system is the load hook. The hook fails by straightening. Once the hook gets elongated or straightened, it should be replaced.

Framed Walls

the load is transferred to the foundation through posts, columns or studs. Framed walls most often have three or more separate components: the structural elements (such as 2×4 studs in a house wall), insulation, and finish elements or surfaces (such as drywall or panelling).

Tiled Walls

typically found in bathrooms or kitchens, it can also be found in bedrooms. They are visually appealing and add a modern touch to any room, including the bedroom. You can experiment with this type of wall finish by using a mosaic design on one side of the wall and painting the rest of the bedroom walls.

Non-Load Bearing Wall

walls only carry their own weight and do not support any structural members, such as beams and slabs. These walls only are used for partition walls or to separate rooms from the outside.

Reinforcement Concrete

Concrete in which reinforcement is embedded n a manner that the two materials act together in resisting forces is called ______________.

Natural Curing

Concrete is allowed to cure naturally without covering anything.

1. When the ground does not have the capacity to support standards, 2. When the ground near the wall is to be free from traffic, 3. When upper part of the wall is under construction.

Conditions of Cantilever Scaffolding (3) *read only

- assembled from interlocking panels or modular systems, made of lightweight and robust plastic - works best in small projects consisting of repetitive tasks, such as low-cost housing estates - light and can be cleaned with water, while being suitable for large sections and multiple reuses - main drawback is having less flexibility than timber, since many components are prefabricated

Definition of Plastic Formwork *read only

- stronger, durable, and have a longer life than timber formwork and their reuses are more in number - can be installed and dismantled with greater ease and speed - the quality of exposed concrete surface by using steel forms is good and such surfaces need no further treatment - does not absorb moisture from concrete and does not shrink or wrap

Definition of Steel and Aluminum Formwork *read only

Water Curing Wet Covering Formwork Curing Membrane Curing Sheet Curing Natural Curing

Different Types of Curing (6)

- Consideration of type of concrete and temperature. - Sides of the formworks must be capable in resisting hydrostatic pressure of the wet concrete. - The formwork base or soffit must be capable of resisting the initial dead load of the wet concrete and the dead load of the dry set concrete. - Once the concrete has gained sufficient strength the formwork can be stripped. - High quality workmanship and inspection are necessary to ensure a high standard and appearance of the resulting concrete structure. - Both shuttering and formwork in its various forms will be supported by falsework.

Formworks Specifications (6) *read only

Water Curing

The application of the water is done to avoid the drying of the concrete surface. Usually, this method applies when the concrete is thinner.

Plain Concrete

The conglomeration of these materials producing a solid mass is called ________________.

substructure; superstructure

The two major components of buildings are the substructure and superstructure. The ___________ is the part of the building that is underneath the ground, while the _____________ is everything that is above ground.

Water Curing

This method is very useful in dry environments as it is not required to pour the water continuously. All the flat surfaces such as road pavements, slabs, footpaths, etc can cure with this method easily.

Water-based Oil-based

Two Types of Membrane Curing

Sheet Curing - Polythene Sheet - Plastic Sheet - Curing Blankets

Two Types of Sheet Curing

Traditional Timber Formwork Engineered Formwork System Re-usable Plastic Formwork

Types of Formworks (3)

Pulley and Sheave Block Chain Hoists Mobile Cranes Winch Jack Shear Leg Tower Cranes Whirler Cranes Derrick Cranes Gantry Cranes

Types of Hoisting Equipment in Construction (10)

Types of Load Bearing Wall: - Precast Concrete Wall - Retaining Wall - Masonry Wall - Pre-panelized load bearing metal stud walls - Engineering Brick Wall - Stone Wall

Types of Load Bearing Wall (6)

Types of Non-Load Bearing Walls: Hollow Concrete Block Facade Bricks Hollow Bricks Brick Wall

Types of Non-Load Bearing Walls

- Single Scaffolding - Double Scaffolding - Cantilever Scaffolding - Suspended Scaffolding - Trestle Scaffolding - Steel Scaffolding - Patented Scaffolding

Types of Scaffolding (7)

Hammerhead Cranes Luffing Tower Cranes Self-Erecting Tower Cranes

Types of Tower Cranes

Framed Walls or Mass Walls

Wall construction falls into two basic categories;

Luffing Tower Crane

also known as a luffing-jib crane. Its design is similar to a hammerhead tower crane, with the exception that the jib is latticed and can be raised and lowered—a motion called "luffing."

Inner Walls

are also referred to as partition walls or interior walls, while outer walls are referred to as exterior walls.

Shear Walls

are harshly important in high-rise buildings subject to lateral wind and seismic forces. Generally, shear walls are either flat or flanged in a section, whereas core walls consist of channel sections. They also have adequate strength and stiffness to manage lateral displacements.

Veneered Walls

are non-structural masonry walls made of brick, stone, or manufactured stone. It is known as anchored veneer because it has an air space behind it.

Mass-Walls

are of a solid material including masonry, concrete including slip-form stonemasonry, log building, cordwood construction, adobe, rammed earth, cob, earthbag construction, bottles, tin cans, straw-bale construction, and ice.

REBARS - lugs - billets

- Cylindrical shaped steel bars with uniformly spaced protrusions called _________ or deformations. - They are hot-rolled from semi-finished steel called _________ - These are required to contain some sort of identification that can be used to identify the mill that produced the reinforcing steel bar.

Staging

- A temporary member which is used to support formwork either for centering or shuttering. - It is done by props, jack, H-frames, cup lock system, wooden ballies, etc.

Centering

- A temporary vertical arrangement and part of formwork to support the horizontal members.

Shuttering

- A temporary vertical arrangement and part of formwork to support the vertical formworks maintain the desired shape.

Truck Mixer Concrete Pump

- Another aspect of concrete placement is the supply of concrete. Both Mobile and Static Pumps have a large hopper to receive concrete from a truck mixer. However, Schwing Stetter offers a mobile product which also carries a supply of concrete with it. The truck mixer concrete pump combines not only a pump and boom but also the concrete storage and transport in the form of a mixer truck, all in one package.

Concrete Pumps

- a tool for conveying liquid concrete. - works by one piston drawing liquid concrete into a cylinder from a hopper while the other one simultaneously pushes its concrete out into the discharge pipes. A valve which determines which cylinder is open to the concrete hopper and which one is open to the discharge pipes switches over each time the pistons reach the end point, and the process continues with the first cylinder now discharging and the second drawing fresh concrete from the hopper. - Commonly used in the construction of large high-rise buildings.

Mobile Pump

- also known as a Truck Mounted Mobile - incorporates both a concrete pump and a placing boom mounted onto a truck chassis. Mobiles come with booms ranging from less than 20 meters to ones which can reach heights of over 60 meters. - The advantage is that it can turn up at a job and be pumping concrete very quickly to anywhere within the range of the boom. - being able to pump at very high volumes quickly to wherever concrete is needed with minimum labor requirements.

Fabric Formwork

- also known as flexible formwork - this system uses lightweight and high-strength sheets of fabric, designed to adjust to the fluidity of concrete and create interesting architectural forms - uses less concrete than rigid systems, which yields savings

Stationary Pump

- also referred to as a Stationary, Line Pump or Trailer Mounted Concrete Pump - mounted on a trailer and requires a separate pipeline to be attached reaching to wherever the concrete needs to be placed. The pipeline is a series of steel or rubber pipes, known also as concrete placing hoses, linked together and manually attached to the outlet of the pump. The other end of the pipe could either be attached to a Separate Placing Boom, allowing the concrete to be placed with precision quickly over a wide area or it might just finish with a rubber placing hose for manual placement. A Static Pump needs to be towed or separately transported to jobs.

Shear Walls

- are a framed walls to resist lateral forces. The horizontal force resistance system is a vertical element. It is used to resist the load of construction by the wind and earthquake. - In a building, a rigid vertical diaphragm is capable of transmitting lateral forces from the exterior walls, floors, and roofs to the ground floor in a direction parallel to their planes. Examples are a reinforced concrete wall or a vertical truss.

Patented Scaffolding

- are made up of steel, but these are equipped with special couplings and frames etc., these are readymade scaffoldings which are available in the market. In this type of scaffolding working platform is arranged on brackets which can be adjustable to our required level.

Tower Crane

- are the crane of swing job type and are mounted on high steel towers. The height of the tower maybe 25 to 30 m and these cranes are found to be suitable in the construction of tall buildings in congested areas. The ground area required for such cranes is very small. - a combination of stationary and mobile units. This combines the advantages of a log boom of derrick crane and mobility of the mobile crane. The rotating structure has an outer framework. The boom is attached to the front end of this framework. The counterweight is provided at the rear end. On the diagonally opposite corners of the base, two separate motors are provided, which give movement to the central shaft

Overhead Gantry Crane

- are the indispensable machines in factories and workshops. In large workshops, there are separate machines for fabrications or repairs of the machine parts. The machine or the components, which are to be repaired, can be transferred to the place of fabrication or assembly with the help of Gantry cranes.

Insulating Concrete Forms (ICF)

- are the most common type of permanent insulated formwork, where concrete structures are insulated with polystyrene boards that stay in place after concrete has cured. - offers energy efficiency and sustainability, contributing to a lower environmental impact from the building sector.

Chain Hoist

- are the popular mechanism for lifting loads of upto tones. The system consists of two sets of chains, namely the hand and load chain. The hand chains are particularly useful for the isolated location, where an electric motor or other types of mechanical equipment are not available. The pull applied through the hand chain is transmitted to the load chain with a multiplication factor of over 20.

Derrick Crane or Guy Derrick

- consists of a vertical mast. This mast is supported by the number of guys and can revolve through 360°. While revolving, the radius of revolution should be such that the revolving structure is not obstructed by the guy wires. The power is supplied by a diesel engine or by an electric motor. - is illustrated in fig. This derrick can be constructed up to 200 tons capacity. In stiff leg type derricks, the guy wires are replaced by trussed structure. This type of derricks is suitable for loads from 10 to 50 tons.

Engineered Formwork System - Steel and Aluminum Formwork

- consists of panels fabricated out of thin steel plates stiffened along the edges by small steel angles. The panel units can be held together using suitable clamps or bolts and nuts.

Wet Covering

- is a method of maintaining the surface moisture level by placing materials like hessian. Use of gunnery bae is also common. - These covering shall place on the concrete surface when it hardens enough to work to please covers. Further, the drying of the concrete surface shall not be allowed due to any reason. - Vertical surfaces in concrete columns, walls, etc. can cure with this method.

Movable Pulley

- is a wheel on an axle or shaft that is designed to support movement and change of direction of a cable or belt along its circumference. - used in a variety of ways to lift loads, apply forces, and to transmit power. In nautical contexts, the assembly of the wheel, axle, and supporting shell is referred to as a "block."

Chute

- is adapted for transporting concrete from ground level to the lower level. It is used when the labour can't reach the place of concrete due to the less space like trenches. The surface should have some slope not flatter than 1 vertical to 2.5 horizontal. Concrete may get slightly compact mass without any separation or segregation.

Steel Scaffolding

- is constructed by steel tubes which are fixed together by steel couplers or fittings. It is very easy to construct or dismantle. It has greater strength, greater durability and higher fire resistance. It is not economical but will give more safety for workers. So, it is used extensively nowadays.

Membrane Curing

- is formed on the concrete surface to avoid the evaporation of the moisture in the concrete. - Liquid form material is sprayed over the concrete surface, and it solidifies and forms a membrane. These materials can apply with brushed or roller.

Single Scaffolding

- is generally used for brick masonry and is also called as brick layer's scaffolding. - Consists of standards, ledgers, putlogs etc., which is parallel to the wall at a distance of about 1.2 m. Distance between the standards is about 2 to 2.5 m. Ledgers connect the standards at vertical interval of 1.2 to 1.5 m. Putlogs are taken out from the hole left in the wall to one end of the ledgers. Putlogs are placed at an interval of 1.2 to 1.5 m.

Double Scaffolding

- is generally used for stone masonry so, it is also called as mason's scaffolding. In stone walls, it is hard to make holes in the wall to support putlogs. So, two rows of scaffolding are constructed to make it strong. The first row is 20-30 cm away from the wall and the other one is 1m away from the first row. Then putlogs are placed which are supported by the both frames. To make it stronger rakers and cross braces are provided.

Luffing Tower Cranes

- is ideal for building projects where there's not much space on either side of the site and you need to work safely. - is able to raise or lower its jib, and that allows it to reduce the slewing radius. - is also a good choice for work sites where two or more cranes are working at the same time. This is because the slewing radius is highly reduced in comparison to standard tower crane types.

Cavity Walls

- is one of the external wall construction types. It is a wall made of 2 leaves/skins, with space/cavity between them. A kind of construction of the building wall consists of an outer wall fitted to an internal wall that is segregated by the wind.

Scaffolding

- is provided as a worker's platforms around the building to work at heights. - is a movable/fixed platform.

Formwork Curing

- is the most effective curing agent in the construction. Especially in thick concretes where the hydration temperature is high, this method is used. - Further, not cost involved as the cost is already covered under the formwork. The only concern is keeping the formwork a bit longer than usual.

Crane and Bucket

- is used for transporting concrete horizontally as well as vertically and also in an inclined way so that it is also called two- or three-dimensional transport. It is a familiar way in medium and large sites in high rise construction projects. In this method transportation of concrete is fast and the placement of concrete takes place at the particular point. It is consists of skips or buckets for containing concrete.

Hammerhead Cranes

- is used to lift effortlessly heavy loads. - also allows you to "rack" the crane. This is moving the trolley in and out along the job with its load suspended but not altering the level of the load. Precise horizontal movement of the load is a significant benefit of using a hammerhead tower crane. - the jib rotates 360 degrees horizontally around the mast at a fixed level — with the structure resembling an upside-down "L."

Hoisting Equipment

- lifts loads with either link or roller chain or wire rope. - powered one of three ways and is used with a number of attachments to facilitate load lift - vertical lifting of freely suspended, heavy, bulky loads, hoisting equipment (or hoists) works in conjunction with overhead cranes and workstation cranes. - Typical applications include helping operators in manufacturing, warehousing and construction to lift loads in support of production or storage activities, loading and unloading, or one process to the next.

Tower Crane

- modern form of balance crane that consist of the same basic parts. Fixed to the ground on a concrete slab (and sometimes attached to the sides of structures), tower cranes often give the best combination of height and lifting capacity and are used in the construction of tall buildings. - will perform hundreds of lifts over the course of a construction project, moving heavy materials like steel and concrete into place for construction workers assembling a building.

Plywood Formwork

- not smooth finished, possible to save cost using large-sized panels, and can be re-use up to 20 to 25 times

Double Scaffolding

Independent Scaffolding

- Direct (or Chute) Discharge - Crane and Bucket - Concrete Pump

Methods for Concrete Works - Prior to the placing of any concrete or concrete pouring, all quality checks are to be completed and the "approval to concrete" instruction shall be issued by the client or consultant.

mixing on the job site; ready mixed concrete

Mixing of Concrete - The process of mixing concrete for construction is done in two different ways-

Grade, Size, Type

Rebar Specs (3)

1. Deformed Steel Bar 2. Mild Steel Rebar 3. European Rebar 4. Carbon Steel Rebar 5. Epoxy-coated Rebar 6. Galvanized Rebar 7. Glass Fiber Reinforced Polymer (GFRP) 8. Stainless Steel Bar

Rebar Types (8)

Truck Mounted Static Pump

can also be mounted onto a truck chassis but without a boom, resulting in a Schwing Truck Mounted Static Concrete Pump. These are perfect for the many quick jobs where a boom might not reach. It might be a slab for an extension at the back of a home or garden where running a pipeline through or round the building is the only option. A normal static pump would need to be towed or delivered on a Hiab truck but with the Truck Mounted Static Pump, the operator can drive it straight to site. Schwing Truck Mounted Static Pumps also come with storage for up to 100 meters of pipeline and other accessories, so everything needed is in one place allowing the operator to pack up and head straight to the next job as soon as a work is completed.

Hoist

is a device used for lifting or lowering a load by means of a drum or lift-wheel around which rope or chain wraps. It may be manually operated, electrically or pneumatically driven and may use chain, fiber or wire rope as its lifting medium.

Electric Winch

is a mechanism in the shape of a cylinder or drum, over which rope or chain is wound. If a ___________ is used only for raising and lowering, it is sometimes referred to as hoist. The ___________ are of two types: - Hand - Power

Construction Wall

is a structural element that divides a space (room) into two spaces (rooms) as well as providing safety and shelter.

Partition Walls

is an interior non-load bearing wall to divide the larger space into smaller spaces. The heights of a partition wall depend on the use which may be one storey or part of one storey. These walls are made up of glass, fiberboards, or brick masonry.

Concrete Curing

is one of the most important factors in concrete construction as it is related to properties such as characteristic strength, permeability, durability, etc.

Mobile Crane

is used in big construction projects for lifting heavy loads. It is used for loading and unloading for material in coal mines. Loading and unloading of ships. To take the load from ground level and place it into the trucks.

Panel Wall

is usually made of wood and is an external non-load wall in a framed building. It is used for the esthetics of both internal and external structures.

Chain Hoist

load to be lifted is held by a load hook while another hook(called support hook) at the top, support the mechanism. The two hooks, however, should not be interchanged as the support hook is made much stronger than the load hook.

Movable Pulley/Pulley

may also be called a sheave or drum and may have a groove between two flanges around its circumference. The drive element can be a rope, cable, belt, or chain that runs over the pulley inside the groove.