Monday, May 30, 2011

The Second Longest Suspension Bridge of Nepal

Thursday, May 19, 2011

Building Financial advisors

Construction projects can suffer from preventable financial problems. Underbids ask for too little money to complete the project. Cash flow problems exist when the present amount of funding cannot cover the current costs for labour and materials, and because they are a matter of having sufficient funds at a specific time, can arise even when the overall total is enough. Fraud is a problem in many fields, but is notoriously prevalent in the construction field[citation needed]. Financial planning for the project is intended to ensure that a solid plan with adequate safeguards and contingency plans are in place before the project is started and is required to ensure that the plan is properly executed over the life of the project.


Mortgage bankers, accountants, and cost engineers are likely participants in creating an overall plan for the financial management of the building construction project. The presence of the mortgage banker is highly likely, even in relatively small projects since the owner's equity in the property is the most obvious source of funding for a building project. Accountants act to study the expected monetary flow over the life of the project and to monitor the payouts throughout the process. Cost engineers apply expertise to relate the work and materials involved to a proper valuation. Cost overruns with government projects have occurred when the contractor was able to identify change orders or changes in the project resulting in large increases in cost, which are not subject to competition by other firm as they have already been eliminated from consideration after the initial bid.[1]
Large projects can involve highly complex financial plans. As portions of a project are completed, they may be sold, supplanting one lender or owner for another, while the logistical requirements of having the right trades and materials available for each stage of the building construction project carries forward. In many English-speaking countries, but not the United States, projects typically use quantity surveyors.

Building Construction Processes

Design team
Shasta Dam under construction in June 1942


In the modern industrialized world, construction usually involves the translation of designs into reality. A formal design team may be assembled to plan the physical proceedings, and to integrate those proceedings with the other parts. The design usually consists of drawings and specifications, usually prepared by a design team including surveyors, civil engineers, cost engineers (or quantity surveyors), mechanical engineers, electrical engineers, structural engineers and fire protection engineers. The design team is most commonly employed by (i.e. in contract with) the property owner. Under this system, once the design is completed by the design team, a number of construction companies or construction management companies may then be asked to make a bid for the work, either based directly on the design, or on the basis of drawings and a bill of quantities provided by a quantity surveyor. Following evaluation of bids, the owner will typically award a contract to the most cost efficient bidder.
The modern trend in design is toward integration of previously separated specialties, especially among large firms. In the past, architects, interior designers, engineers, developers, construction managers, and general contractors were more likely to be entirely separate companies, even in the larger firms. Presently, a firm that is nominally an "architecture" or "construction management" firm may have experts from all related fields as employees, or to have an associated company that provides each necessary skill. Thus, each such firm may offer itself as "one-stop shopping" for a construction project, from beginning to end. This is designated as a "design Build" contract where the contractor is given a performance specification and must undertake the project from design to construction, while adhering to the performance specifications.
Several project structures can assist the owner in this integration, including design-build, partnering and construction management. In general, each of these project structures allows the owner to integrate the services of architects, interior designers, engineers and constructors throughout design and construction. In response, many companies are growing beyond traditional offerings of design or construction services alone and are placing more emphasis on establishing relationships with other necessary participants through the design-build process.
The increasing complexity of construction projects creates the need for design professionals trained in all phases of the project's life-cycle and develop an appreciation of the building as an advanced technological system requiring close integration of many sub-systems and their individual components, including sustainability. Building engineering is an emerging discipline that attempts to meet this new challenge.

Building Construction Processes

Building construction is the process of adding structure to real property. The vast majority of building construction projects are small renovations, such as addition of a room, or renovation of a bathroom. Often, the owner of the property acts as laborer, paymaster, and design team for the entire project. However, all building construction projects include some elements in common - design, financial, and legal considerations. Many projects of varying sizes reach undesirable end results, such as structural collapse, cost overruns, and/or litigation reason, those with experience in the field make detailed plans and maintain careful oversight during the project to ensure a positive outcome.


Building construction is procured privately or publicly utilizing various delivery methodologies, including hard bid, negotiated price, traditional, management contracting, construction management-at-risk, design & build and design-build bridging.
Residential construction practices, technologies, and resources must conform to local building authority regulations and codes of practice. Materials readily available in the area generally dictate the construction materials used (e.g. brick versus stone, versus timber). Cost of construction on a per square metre (or per square foot) basis for houses can vary dramatically based on site conditions, local regulations, economies of scale (custom designed homes are always more expensive to build) and the availability of skilled tradespeople. As residential (as well as all other types of construction) can generate a lot of waste, careful planning again is needed here.
The most popular method of residential construction in the United States is wood framed construction. As efficiency codes have come into effect in recent years, new construction technologies and methods have emerged. University Construction Management departments are on the cutting edge of the newest methods of construction intended to improve efficiency, performance and reduce construction waste.

Monday, May 16, 2011

Timber or Steel Prefabricated Frame

Once the floor structure is in place the walls are erected directly on top of the chipboard or slab. Walls act as a loading bearing support for the roof and provide space for openings such as doors and windows, and they enclose the house and seal it from weather. Walls comprise of either a structural frame and cladding or solid masonry.
This is the most common type of house wall framing.
Steel itself is more termite resistant than timber however timber is more forgiving and accommodates alterations more easily. Timber framing can be pre-treated for termite prevention however the chemicals do weaken in time.
This type of frame is usually pre-made to order. It consists of:
  • Plates (horizontal top and bottom members)
  • Studs (vertical members between the plates)
  • Noggins (additional horizontal members between studs)
  • Galvanised strap bracing is added diagonally to brace the frame and stop racking.
Metal angle bracing is essential for structural integrity in walls (as it is for pier areas, floors, and roofs).
Openings in wall frames require a timber, steel or lightweight aluminium overhead beam called a Lintel. Steel frames and load bearing brick walls, although termite resistant, do not accommodate changes easily. Also be aware if you are cutting holes in the framework to accomodate kicthen and bathroom conduit that you will need to follow the latest Australian standard to insure that the framework remains structurally sound.

Post and Beam

Post and Beam can be steel or timber. It is used when building elements are to be exposed. Post and beam construction is assembled on site and is in-filled with a timber frame. This method requires more precision and is more labour intensive but can look very good. Often laminated beams of sheets of timber glued together under pressure called "HySpan" (http://www.dindaslew.com.au/?id=7) are used. They are very strong, straight and never warp.

Solid Masonry

This includes double brick, core filled concrete block work and natural stone and mud-brick as both a load bearing structure and an outside cladding surface to seal out weather.
With double brick construction both layers of wall are load bearing, all plumbing and lighting conduit should be cattered for during the initial construction period. Altering masonry or brickwork for bathroom and kitchen conduit after this time is labour intensive.
Windows and doors need steel or concrete lintels to support masonry above. In some cases the exterior brick is rendered, bagged or painted. (Click here to read more about Cement Rendering, or go to the Toptex website to learn about their lightweight smart brick and solid plastering services).
All masonry walls require damp proofing to stop rising damp creeping up surfaces.
All single skin external walls such as sandstone, core filled concrete block work and mud brick will require a large roof overhang or surface waterproofing to prevent water penetration and or mould build-up.

Footings & Floor Construction

The type of footings used for a new home will be suggested by the home designer with possible consultation with a geo-tech consultant. The factors that influence the type of footings are:
  • Weight of building
  • Wall construction type and height
  • Soil type
  • Slope of the block
  • Budget
  • Drainage requirements on the block
There are five main types of footings:

Strip Footings

A Strip Footing is a relatively small strip of concrete placed into a trench and reinforced with steel. The footing supports the load of the exterior walls and any interior wall that is load bearing or supports a slab such as for a bathroom. Strip footings can be used for both traditional timber and concrete floors. They are one of the most common footing used in Australia.

Concrete pad footings.

A concrete pad footing is the simplest and cost effective footing used for the vertical support and the transfer of building loads to the ground. These footings are "isolated" ie there is no connection between them. They are also reinforced.
Holes are dug (say 400mm wide x 400mm deep) into the ground and fitted with a reinforcement cage then filed in with a concrete mix to ground level.
Concrete pad footings are used to support light weight timber-framed houses.

Pole Construction (Post and Concrete)

For this type of footing a hole is dug into the ground about 800mm wide x 1600mm deep. A pole is then placed into the hole and ready mixed concrete is back filled around the pole. Pole construction footings do not require steel reinforcement (or an engineer) and are therefore also one of the least expensive footings types.
Pole Construction is the most economical way of constructing a pier/footing on sloping land but engineer's details will be required for the builder and certifying authorities. A few essential considerations are:
  1. How long the poles will need to be and the spacing?
  2. What will be the correct height of all poles?
  3. How far down will the pole will need to penetrate?
  4. How will the concrete around the pole need to be finished to reduce wood rot?
  5. What will the diameter of the poles need to be?
  6. What are the poles are made of (steel or timber)?

Grout Injected Piles

Where it is impossible for a footing to be constructed, a pile which is both pier and footing is used.
This method is only used in unstable or potentially unstable soils such as mud flat estuary areas and beach front etc. Grout injected piles are "isolated" footings and/or piers, which are cement grouted (not concrete) and steel reinforced, with an overall diameter of around 600mm.
The piers are installed by inserting a cork like screw (Metal Auger) attached to a Backhoe in to the ground. The Auger screws all the dirt out of the pier hole that will be around 6 meters in depth. Once all the dirt is removed the grout is injected through the end of the rotating Auger into the hole. As the hole fills with grout the rotating Auger is slowly removed ensuring no dirt collapses back into the hole. The Auger machine drills out the pier holes with minimal disturbance to adjoining soil and structures. Mini piles use the same process and materials as grout injected piles but are around 200mm in diameter

Timber Piles

Timbers piles are a more cost affective method of constructing structural piles. Timber piles are long timber poles around 6000mm in length and 400mm in diameter that are hammered deep into the ground by a pile driving rig (big hammer). The piles are driven into the ground their full length or until the pile hits bedrock. If the pile hits a floating bolder it will skew in the ground but the pile will be amply stable to support a floor structure. Pile driving vibration can disturb adjacent buildings, resulting in cracking, failure and even collapse.

Sunday, May 15, 2011

History

Quite naturally, early dam builders began by using plentiful materials like sand, timber and brush, and gravel. Their construction method consisted of carrying the materials by the basketful and loosely dumping the fill, so many of these dams may have survived only a few years. Scientists have not been able to pinpoint dates for the earliest dam construction, but they do know dams were needed where food was grown and in areas prone to flooding.
Design of fill dams is based on experience; while failures are unfortunate and sometimes catastrophic, they are also the best teachers, and many engineering advances have been founded on careful study of earlier failures. The engineers of ancient India and Sri Lanka were the most successful pioneers of fill dam design and construction, and remains of earth dams can still be seen in both countries. In Sri Lanka, long embankments called tanks were built to store irrigation water. The Kalabalala Tank was 37 mi (60 km) long around its perimeter.
The most famous earth fill dam recently constructed is the Aswan High Dam that was built across the Nile River in Egypt in 1970-1980. An earth fill dam was also the victim of a spectacular failure in June 1976 when the Teton Dam in Idaho eroded from within due to incorrect design of the zones inside the dam that allowed seepage, failure, and flooding of the valley downstream. Although earth dams tend to be short and broad, Nurek Dam in Tajikistan is 984 ft (300 m) high.


Read more: How fill dam is made - material, making, history, used, processing, dimensions, product, History, Raw Materials, Feasibility and Preliminary Design, Design, The Construction Process, Quality Control http://www.madehow.com/Volume-5/Fill-Dam.html#ixzz1MP83ydf2