From topographic and hydrological data, structural system is to be designed and constructed to facilitate passage of khors streams or drains under the road embankment. The consultant, jointly with the hydrological expert will decide upon the most suitable hydrological structures required for the chosen alignment.
However, the actual time needed, for phase I, will depend on the feasibility studies actual volume of work required for this project. The actual time of Phase II will be depending on the feasibility studies to proceed for the detailed engineering design. Inception Report: will be submitted within 6 weeks from the commencing date, it will include the outcomes of route alignment and the summary of other conducted activities and recommendations.
Interim Report: it will be submitted within 12 weeks from the commencement date, describing the completed services, works in progress proposed recommendations. Draft bidding Documents: upon competition of this stage three copies of the following documents will be submitted within 24 weeks from the commencement date: a.
Prequalification Document for Contractor b. Bidding Documents: including instructions to bidders, condition of contracts based on FIDIC , Technical specifications, bills of quantities, drawing plan-profile, structures details and others and forms of bids and guarantees. Confidential Reports including Road Auditing, design, material and cost and time estimates reports. Final Documents: within 30 weeks from the commencement of works we will submit eight copies of revised documents to the client.
Consultant Professional Staff To carry out the two phases of the project, the Consultant shall set up a technical and non-technical Staff.
The Services shall be carried out by the personnel specified herein, for the respective periods of time indicated therein. Where the Consultant replaces any of his personnel, before the completion of the Services, any additional cost of such replacement shall be borne by the Consultant.
The Consultant Head-Office shall provide all necessary back-up services required by the team leader. Such back-up will include the services of consultants, specialists, and other Head-Office Experts, for specific periods. Basically, the team leader shall be responsible for ensuring that the studies and design progress is within approved time-schedule. This group will carry out the feasibility studies and the detailed engineering design.
The minimum number of personnel, compatible with the scope of services specified in the TOR, has been considered in our Proposal. The proposed Consultants and Experts have a great deal of experience and expertise in the entire range of consultancy services and activities required for this Project.
Highway Expert : Eng. Structural Expert Bridges : Dr. Abdalla Khogali MD 4. Hydrologist Expert: Eng.
Surveying Consultant: Eng. Related Papers End-term jury project By het hhh. Theory By Sailesh Jha. Download PDF. The resulting hard substance, called 'clinker', is then ground with a small amount of gypsum into a powder to make 'Ordinary Portland Cement', the most commonly used type of cement often referred to as OPC. Portland cement is a basic ingredient of concrete, mortar and most non-specialty grout.
The most common use for Portland cement is in the production of concrete. Concrete is a composite material consisting of aggregate gravel and sand , cement, and water. As a construction material, concrete can be cast in almost any shape desired, and once hardened, can become a structural load bearing element. Portland cement may be grey or white.
The fly ash is pozzolanic, so that ultimate strength is maintained. Because fly ash addition allows lower concrete water content, early strength can also be maintained. Where good quality cheap fly ash is available, this can be an economic alternative to ordinary Portland cement.
In countries where volcanic ashes are available. However, silica fume is more usually added to Portland cement at the concrete mixer SAND Sand is a naturally occurring granular material composed of finely divided rock and mineral particles. The composition of sand is highly variable, depending on the local rock sources and conditions, but the most common constituent of sand in inland continental settings and non-tropical coastal settings is silica silicon dioxide, or SiO2 , usually in the form of quartz.
The second most common type of sand is calcium carbonate, for example aragonite, which has mostly been created, over the past half billion years, by various forms of life, like coral and shellfish. It is, for example, the primary form of sand apparent in areas where reefs have dominated the ecosystem for millions of years like the Caribbean. For a good concrete mix, aggregates need to be clean, hard, strong particles free of absorbed chemicals or coatings of clay and other fine materials that could cause the deterioration of concrete.
Aggregates, which account for 60 to 75 percent of the total volume of concrete, are divided into two distinct categories-fine and coarse. Coarse aggregates are any particles greater than 0. Gravels constitute the majority of coarse aggregate used in concrete with crushed stone making up most of the remainder. Natural gravel and sand are usually dug or dredged from a pit, river, lake, or seabed. Crushed aggregate is produced by crushing quarry rock, boulders, cobbles, or large-size gravel.
Recycled concrete is a viable source of aggregate and has been satisfactorily used in granular sub bases, soil-cement, and in new concrete.
Aggregate processing consists of crushing, screening, and washing the aggregate to obtain proper cleanliness and gradation. If necessary, a benefaction process such as jigging or heavy media separation can be used to upgrade the quality.
Once processed, the aggregates are handled and stored in a way that minimizes segregation and degradation and prevents contamination. Aggregates strongly influence concrete's freshly mixed and hardened properties, mixture proportions, and economy. Consequently, selection Grading limits and maximum aggregate size are specified because grading and size affect the amount of aggregate used as well as cement and water requirements, workability.
The quantities of aggregates set forth in the tabulations are for oven dry materials having a bulk specific gravity of 2. For aggregates having a different specific gravity, the weights shall be adjusted in the ratio that the specific gravity of the material used bears to 2. This allows to provide a homogeneous bond between the concrete slab and its foundation which is important for the later behaviour of the pavement structure.
For roads with a base, drainage of the water must be provided. Mud, leaves, etc. When the base is permeable, it should be sprayed with water in order to prevent the mixing water from being sucked out of the concrete.
However, if the base is impermeable e. If the sub grade has to be levelled, it is advisable to do this by using a granular material: either slag or coarse aggregate e.
It must always be avoided that water is sucked from the cement paste into the substructure or the base. This can be accomplished by either moderately moistening the sub grade, or by applying a plastic sheet on the substructure of the pavement. The latter work must be done with care, to prevent the sheet from tearing or being pulled loose by the wind.
The mix constituents and admixtures have to be The number of aggregate feed bins has to equal at least the number of different aggregate fractions. The bins shall have raised edges to prevent contamination of the aggregate fractions.
The equipment for loading the materials shall be in good condition and shall have sufficient capacity to be able to continuously feed the bins. The bucket of the loaders shall not be wider than the bins. The content of the cement silos and the water tank are in proportion to the production rates.
For small works, permanent concrete mixing plants are often called on. In that case, mixing plants that are inspected and that can deliver Indian quality certification concrete should be used.
The number depends on the yield at the construction site, the loading capacity of the trucks and the cycle time i. The loading capacity and the type of truck to be used depend on the nature of the work, the haul roads and the concrete paving machines. Usually, the specifications prescribe that the concrete has to be transported in dump trucks as paving concrete consists of a relatively dry mix having a consistency that makes transport and unloading in truck mixers difficult.
Furthermore, dump trucks can discharge the concrete faster. For small works and in urban areas, the use of truck mixers is increasingly accepted. Under these circumstances an admixture e. The necessary measures have to be taken to prevent changes of the water content and temperature of the concrete during transport. To this end, the specifications prescribe to cover the dump trucks by means of a tarpaulin. This equipment meets both the requirements for quality and for the envisaged rate of production.
Conventional concreting trains riding on set up rails, are hardly used any more for roadwork's in our country. For this reason this manner of execution will not be dealt with here.
However, the technique of manually placing the concrete using forms is still applied in certain cases, such as for the construction of roundabouts with a small diameter, at intersections, for repair work or when the execution conditions are such that slip form pavers cannot be utilized.
This occurs increasingly often in urban areas for the construction of pavement surfaces of exposed aggregate and possibly coloured concrete. The track runway is a determining factor for the steering and consequently its surface has to at least as smooth as the concrete paving surface itself. The runway surface has to be permanently cleaned prior to the passage of the tracks. EXECUTION The supply of the concrete has to be arranged in such a way that a continuous placement can be guaranteed without detrimental interruptions as each standstill can cause unevenness's.
This implies a sufficient capacity of the concrete mixing plant and of the means of transportation of the concrete.
The concrete must be discharged gradually, in order to limit the drop height. It cannot be overemphasised that properly spreading the concrete in front of the slip form paving machine is very important for the final quality of the work, especially with regard to the smoothness. It is of great importance that in front of the slip form paver, a constant and sufficient amount of concrete is available at all times so that a continuous paving process can be guaranteed.
In the end of this construction proposal, the details of the work plan are also mentioned that will be adopted for the project of the said road construction. Create your own Construction Proposals by using the following template,.
Skip to content Such proposal is a written document that is used by individuals or companies to pursue or approach the prospective clients or companies for different purposes. Borrow Where sufficient quantities of suitable cut material are not available, additional material shall be excavated from approved borrow areas.
In lieu of borrow, cuts may be widened or slopes of cuts may be flattened, provided that the Engineer determines the need for such action before start work on any particular cut. Disposal of Surplus Material Any surplus material arising from excavations, including any waste or oversize material bladed off the road, shall be disposed of as directed by the client Engineer who may require that the material be utilized in the uniform widening of fills or the flattening of slopes, or be deposited in such places and for such purposes as he may direct.
Spoil material need not be compacted but must, if required, be spread, shaped and given a smooth surface such as is formally obtainable with careful bulldozer operations. Spoiling alongside roads or tracks will not be permitted. The potholes and depressions that may appear on the existing roads surfaces shall be repaired.
These distresses require backfilled with approved imported material and compacted to the required density. Any cracks shall be filled with soil and then compacted.
The road camber will be repaired wherever required. Any portion of the topsoil which by reason of its inadequate density will be compacted. The topsoil surface cross slopes and sides edges will be made proper as on the drawings. The dimensions of topsoil surface shall be in accordance with the cross-sections and details shown on the Drawings. The areas to be surfaced shall be cleaned of all dust, dirt, dung or any other foreign materials that may be deleterious to the surfacing.
Before any priming material is sprayed on the surface the layer to be primed shall be checked for compliance with the specified tolerances and corrected if out of tolerance. Also before spraying the prime coat, the layer to be primed shall be broomed and cleaned of all loose or deleterious material, taking care not to cause any damage to the layer. A light spray of water, sufficient to dampen the surface, shall be uniformly applied to the layer immediately before the application of the prime.
Prime coat application Prime coat binder will be applied on the topsoil surface for promoting adhesion between the soil and the surface dressing. Any excess prime shall be removed with blotter sand.
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