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Objectives of the cladding system are to provide enclosure for the building, it is means cladding can protect the building frame and interior space from the intrusion of sound, water, wind, heat and cold, and sunlight that means all the intrusion can be blocked by cladding that refer to non load-bearing exterior enclosure of buildings (not include roof), It is speed of dry construction that prefabricated off the site. Then, cladding can impose minimal additional dead load, enhance architectural concept and control internal environment. The cladding system must be compatible with the structural frame and other building elements, which together must satisfy a range of functional requirements, the scope and nature of which vary subject to the individual building.
Exclusion of wind and rain
It is commonly practice to construct solid cladding systems with an outer leaf as a rain screen and inner leaf of light weight block for insulation. Material used to seal joints was required to be resilient enough to accommodate movement and resist weather deterioration. Cladding should have its strength and stability to support its own self weight between points of supports or fixings to the structural frame. The stability is to against lateral wind pressures. It had the allowance for differential movements between itself with the structural frame and other adjacent building elements. For the weather resistance, it must fulfill resistance to wind, rain and others.
Durability & freedom of maintenance.
Cladding must had its durability, freedom from maintenance, and ability to weather well, that's means it must have minimum frequency and extent of work necessary to maintain minimum functional requirements & acceptable appearance. For cladding type of masonry, its required a little maintenance. For a glass cladding, its require frequent cleaning & renewal of seal and for a sheet metal such as bronze, aluminium, stainless steel, it must be oxidation and faded.
Control of internal temperatures
The solar gain through glass panel and the thermal control can be achieved by deep recessed window used in conjunction with external vertical fins, non-transparent external louvers and used of special solar control glass. For it's temperature, glazing use of solar control glass.
The material used for cladding must be fire resistance. The lining materials used for insulation are from the non-combustible material. Fire resistance may need to be provided subject to proximity of other buildings and the use class of the building in question. The Restriction of flame spread to internal and external surfaces and within voids must be taken into consideration of its fire resistance.
Addition insulation needs to be provided by lining of the cladding material. Thermal insulation Achievement of U-values laid down in the Building Regulations and Standard Assessment Procedure (SAP) approach allows one building element to compensate for another. The thermal was to avoid of problems arising from 'cold bridging' and from surface and interstitial condensation. It also can reduce of air leakage.
Used of resilient pad to prevent sound originating within the structure to be transferred vertically through cladding members, insulation against airborne sound originating from external source sound can be prevented by utilized double glazing panel to window area. The prevention of sound originating in one part of the building being transmitted to other areas via cladding members/elements.
2b ) Construction methodology of proposed road
There are two types of road which is flexible pavements and the rigid pavements. For low/little maintenance and reasonable non skid properties, I will suggest rigid pavements for clients. Compare to the flexible pavements, it has high maintenance which is need to resurfacing every 5 years after constructed. It also with good non skid properties whereas the client only want reasonable for non skid properties.
Rigid pavements construction methodology
The construction of roads can be considered of two category of preparation/earthworks (site clearing) and pavement construction. Before any road works undertaken thorough soil investigation should be carried out to determine the nature of the sub-grade. Trial holes should be taken down to at least 1m below the proposed formation level. The information required from these investigation to ensure that a good pavements design can be formulated is the elasticity, plasticity and internal friction properties of the sub-grade.
This stage include removing top soil, scraping and grading the exposed surface to the required formation level, preparing the sub-grade to receive the pavements, and forming any embankments and/or cutting. Tree roots, particularly those of fast-growing deciduous tree can also damage in heavy clay soils by extracting vast quantities of water from the sub-grade down to a depth of 3m.
Preparation of sub-grade layer
Same as construction method for flexible pavements whereas it starts after installation of services has finished such as ground surface drainage, piping for water supply and electrical, and it should be adequately protected against the water. It must be compacted until reaching uniform density for the whole width and to falls. Then, it should replaced the unsuitable material and also should have un soaked C.B.R (California bearing ratio) of 15% and lastly it covered 50-75mm of sand/quarry dust.
Preparation of base layer
The base layer is laid over the sub-grade, and is required to form a working surface from which to case the concrete slab and enable work to proceed during wet and frosty weather without damage to the sub-grade. Generally, granular materials such as crushed concrete, crushed stone, crushed slag and suitably graded gravels are used to form the base layer. The thickness will depend upon the nature and type of sub-grade.
slip membrane of polythene sheeting
Before the concrete is laid, the base layer should be covered with a slip membrane polythene sheet which will also prevent grout from the concrete slab. Concrete slabs are usually laid between pressed steel roads form, which are positioned and fixed to the round with steel sakes. These side form are designed to provide the guide for hand tamping or to provide for a concrete train consisting of spreaders and compacting units. Curved or flexible roads forms have no top or stakes.
In-situ concrete slab
The thickness of concrete used will depend upon the condition of the sub-grade and intensity of traffic, and on whether the slab is to be reinforced. With a normal sub-grade using a base layer 80mm thick the slab thickness would vary from 125mm for a reinforced slab carrying light traffic to 200mm for unreinforced slab carrying a medium to heavy traffic intensity.
Reinforcement generally in the form of a welded steel fabric can be included in rigid pavement constructions to prevent the formation of cracks and to enable the number of expansion and contraction joints required to be reduced.
Joint used in rigid pavement may be either transverse or longitudinal. There are type of joints namely expansion joints, contraction joints, longitudinal joints, construction joints and warping joints. Road joints can require filler or sealant and need to be compressible whereas the latter should protect the joints against the entry of water and grit.
2c) Performance and specify material
Material that can be used to fill the void of disused structures such as culverts, redundant sewers, cellars and basements and also for soil structural stabilization such as bridge abutments, tunnel stabilization and embankments is concrete, aerated concrete. It is also known as foamed concrete or cellular concrete is not an autoclaved aerated concrete product, it is conventional concrete with a wide range of densities, choice of aggregates and mix designs. Aerated concrete is made with fine aggregates, cement, and an expansion agent that causes the fresh mixture to rise like bread dough. This type of concrete contains 80% air. In the factory where it is made, the material is molded and cut into precisely dimensioned units. Unlike other concrete applications, no aggregate larger than sand is used. The binding agent was quartz sand, lime and/or cement. Aluminum powder is used by volume and also with water. When mixed and cast in forms, several chemical reactions take place that give aerated concrete for its light weight 20% less than the weight of ordinary concrete and thermal properties. Aluminium powder reacts with calcium hydroxide and water to form hydrogen and the hydrogen gas foams the raw mix to double the volume. Then, at the end of the foaming process the hydrogen escapes to the atmosphere and is replaced by air.
Aerated concrete is highly workable, low-density material incorporating up to 50% entrained air generally self-leveling, self-compacting and may be pumped. Risk of plastic shrinkage or settlement cracking is significantly lower than that of normal concrete. Foamed concrete is ideal for filling redundant voids such as disused fuel tanks, sewer systems, pipelines, and culverts. It is also good in thermal insulation properties and considerable savings in material due to the porous structure. Using an appropriate technique of production, aerated concrete with wide range of densities can be obtained and this would be beneficial in manufacturing aerated concrete products for specific applications, such as structural, partitions, and insulation. Even though, aerated concrete was initially envisaged as an insulation material, there has been renewed interest on its structural characteristics in view of its lightweight, savings in material, and potential for large scale utilization of wastes like pulverized fuel ash. In terms of Cost Effective, using of aerated concrete, the operating cost savings can be realized through reductions in maintenance, energy bills and insurance. For its durability, and its environmental impact, is an important factor when considering use of a building material. Aerated Concrete has proven to be a very durable material and it provides a very low maintenance building, saving considerable time and money in upkeep over the life of the building. Aerated concrete can also be drilled, nailed, grooved, routed, shaped, sculpted, carved, coated, floated, screwed into and milled with common tools and finished with paint, tile, drywall, plaster, or veneer.
Others performance of the aerated concrete is high entrained air content. It can resistant to freeze/thaw damage and good thermal and acoustic insulation. It is also in good cohesion which means its stable foam structure reduces settlement and it can reduce bleeding and segregation. Besides that, it will control density and strength. Low strength allows removal for, due to low density wall made of aerated concrete is light as 3 times as brick wall, aerated concrete is easy to cut, install and transport and man-hours needed for installation of aerated concrete blocks are three times less than for brick walls. Range of densities and strengths available for each foamed concrete type was performance of subsequent access to services. Aerated concrete makes a stable structure that generally be surfaced after twenty four hours, its durability and dimensional stability can be reached.
2d ) Activities in external works at start
External works means construction works done externally from the main building and it can be classified in their category such as drainage requirements, temporary construction, public utilities, special industries services, minor external building such as ancillary building and also security and lighting. Some item will be done at early of contract stage and the rest will be complete at the end of contract.
Early stages of the construction:-
Drainage requirements. Drainage main runs (connection to designated falls either surface or sewage) Drainage is the natural or artificial removal of surface and sub-surface water from an area. There are two types of drainage. The surface drainage is the drainage to removal and disposal of water from the surface of a pavement while sub-surface drainage was drainage for the use of underground pipes and other fittings to direct the flow of water from where it's not wanted to some other place. This includes land drainage( removing and disposing of surplus groundwater from gardens, fields and other plots of open land). The contractor should made proper provision of the drainage of surface water from the work site include rainwater from surrounding areas which drain on to the site and civil engineer or site engineer was responsible for drainage in construction projects. They set out from the plans all the roads, Street gutters, drainage, culverts and sewers involved in construction operations. Then, contractor shall at his own cost to provide and form, fix and maintain such pumps, drain and other temporary works necessary for the proper drainage of the site so that no flooding or other damage or disturbance is caused to areas surrounding the works or to the works throughout the duration of the contract.
Temporary construction which are access road, paved areas, storage & car parks and its include access arrangement, storage facilities, car parks, hard areas for plants & machinery for foundation construction & service mains to building entry. They are major component before any constructions of building can take places is provision of a hard access to all parts of the site, hard storage for materials and also for site facilities and car parking. The main function of temporary access are to minimize the cost temporary road and access which contractor will lay the base course of permanent road and the site temporary road can be kept dry by laying the drainage system as soon as possible. All necessary temporary entrance to the site especially for the access should be provided and maintained by the contractor. Access to and within the site as long as required to the approval of the S.O. The position of the site access is to be made shall be indicated on the site plan or as approval by the S.O and all the arrangements should be made by the contractor and also obtain all approvals and permissions required at his own cost. For the storage, contractor shall be provide and maintain on the site in positions as approved by the S.O the following adequate, secure and weatherproof temporary buildings for use during the execution of that contract. The contractor shall provided shed for storage of cement with the floor raised 300mm above the ground, shed for bar-bending and similar works, store for other building materials and also office for contractor use. Other addition store is depends on that project.
Public utility is referred to facilities provided by the contractor such as water, electricity & telecom. Public utilities need to be planned ahead before any major structures are built and any constructions of service mains and ducts should start concurrently with foundation construction stage so as not hinder the construction activities. The water used for consumption that shall be obtain directly from the water authority mains which is Jabatan Bekalan Air ( JBA ) and where such water supply is not available, potable water should be provided from the sources approved by the S.O. The potable water shall comply with the requirements of the guidelines issued by the Ministry of Health. While for the electricity, it shall be obtained from Tenaga Nasional Berhad ( TNB ). Where such the power supply cannot be supplied, generator set can be used but safety precautions must be taken. The use of kerosene lamps should be not allow. Telephone for S.O shall be provided by the contractor at the S.O's site office for the sole use of the S.O in connection with the supervision and administration of the contract and pay for all installation, rental, call charges and disconnection. The call charges up to a maximum limit of RM__ per month depends on that project and shall be paid and borne by the contractor.