Safety Management & Site Establishment Unit 9 – Site Establishment and Procurement
Site Establishment This section of this course seeks to focus on the physical establishment of a site, as with the selection of common temporary works, plants and equipment You should be aware that all planning at management level has already been mapped out and approved for actual commencement of works on site, including the preliminary mobilisations
Learning Outcomes Upon completion of this lecture, students should be able to; Outline how to set up a site and enable works to progress Demonstrate knowledge of how to run a construction site Discuss in detail the procurement undertaken on a construction site
Class Activity: Designing a Site Layout Working as a group, you are to assume the role of a contractor’s site team: Identify factors affecting the site layout design and propose a fully annotated site layout for the scenario you are given; Scenarios 1. London city centre 6 storey end of terrace office block construction on a 600m2 of congested land. Footprint cannot be more than 60% of the site. 2. 3 storey luxury house project in rural highlands. 1000m2 farmland, 200m2 footprint. Difficult for vehicular access. 3. 30 storey mix development tower block in a wealthy middle-eastern capital city. 5000m2 land, 2500m2 footprint. 4. 4 identical 25x20m 12 storey social housing blocks in Glasgow in a 60x70m steep, sloping land. Output: 1 spider diagram containing all the considerations and 1 site layout demonstrating these considerations as a design. (You can make assumptions about the site features or ask tutor what to assume… )
Contractor’s Site Obligations – Layout and Enabling Work The contractor’s team should visit the site An examination of the topography of the site may focus attention on the layout of a facility for maximum use of the available space The production or processing of design and operation often dictates the site layout
Contractor’s Site Obligations – Layout and Enabling Work Site layout: Site space allocation for material storage, working areas, units of accommodation, plant positions, general circulation areas, and also access and egress for deliveries and emergency services
Contractor’s Site Obligations – Layout and Enabling Work Poor layout can cause construction problems such as inadequate space for staging, limited access for materials and personnel, and restrictions on the use of certain construction methods Thus, design and construction inputs are important in proposing the site layout
Contractor’s Site Obligations – Layout and Enabling Work The contractor must visit the site to gain some insight in preparing or evaluating the proposal of its layout for erecting temporary facilities and the field office, by verifying: o access roads o water o electrical and o other service utilities in the immediate vicinity They can also observe any interferences of existing facilities with construction and develop a plan for site security during construction
Contractor’s Site Obligations – Layout and Enabling Work In examining site conditions, particular attention must be paid to: o environmental factors such as drainage, groundwater and the possibility of floods o presence of hazardous waste materials from previous uses Depending on the contract’s requirements, some common site facilities to be catered by the contractor, as with his obligations to be adhered to, are as follows:
(1) Site Safety, Health and Welfare: A sound knowledge of the various Factories Acts and Working Rule Agreements is essential, especially as safety, health & welfare issues are concerned Based on the contract’s health and safety policy, the site manager has to ensure strict adherences wherever possible, and to consult with the relevant authorities when in doubt Welfare can range from the provision of clean sanitary facilities, regular waste disposals and housekeeping, to a comfortable workers’ mess, subject to budget and requirements
(2) Site Administration and Security Non-productive, or part productive members of the site management team that are not usually included in the company’s general overheads, but under a separate project budget (e.g. part- time employees or employment by project basis) Adequate staffing must be allowed in relation to the labour strength and activities that have to be controlled Insufficient supervisory personnel is a major cause of losses All site admin staff, as with project planning, will have to be finalised at the head-office prior to any physical site mobilisation
(2) Site Administration and Security (cont’d) Advice should be sought from the company’s planning department on the security precautions that should be implemented Vandalism and trespass are common problems and every effort should be made to ensure that the site is secure throughout the active contract duration, particularly where large temporary openings may be necessary Fenced compound areas will require gates and sometimes CCTV The cost of security is usually high, but this cost must be balanced against that of wastage, damage, loss and delay
(3) Ensuring Legitimacy and Competence of all Workmen Most countries have statutory bodies to strictly govern and ensure that contractors and labour agencies recruit only workmen with a specified level of skill or trade through accredited certifications Discovery and subsequent confirmation of unlicensed workmen on site, may result in the immediate stoppage of site works pending HSE investigations, with hefty fines and possible imprisonment of the contractor’s top management These measures helping to reduce the accident rate, in tandem with producing buildings of high and consistent qualities
(4) Plant and equipment While a check list reduces the risk of omission, attention should be paid to ancillary items, essential accessories and components that render the plants and equipment effective in fulfilling their functions on site Areas to harbour major plants and equipment on site, shelter, security and maintenance issues, will all have to be decided upon
(5) Scaffolding: Scaffolding may be examined under the headings of external and internal works, in full compliance to national and local regulations Both require quantification and an assessment made of the amount of time that they will be needed and the time to erect Adaptations required after erection, particularly in regard to attendance on sub-contractors, should be noted A suitably firm and level base must be made available for erection
(5) Scaffolding (cont’d) Advantageous to consult specialist-scaffolding firms to undertake an overall package Mobilisation and installation of scaffold systems on site are detailed into the project schedule, to maximise its use on site, and not to impede works It is imperative to complete high works, prior to the dismantling
(6) Protection against Inclement Weather In places where heavy rainfall is a norm, additional waterproofing measures in the forms of temporary/portable shelters, waterproofed sheeting … etc. have to be stocked in the site store Depending on the region’s climate, all considerations pertaining to the effects of weather should be viewed seriously (e.g. productivity and work sequences differ dramatically between summer and winter) Too hot or sunny conditions can also delay the works and protection will need to be considered
(7) Water Supply The position and properties of the most suitable and available temporary water supply source for the site Upon confirmation of the location, a check with the water supply authority on charges and availability will follow It is rare for a permanent new supply to be incorporated initially Allowances will usually be made in order to provide temporary water sources at appropriate positions In high-rise construction, the pressure levels required have to be established and the appropriate riser installed as well
(8) Lighting and Electrical Supply If there are heavy plant requirements, then the service authority needs to confirm that sufficient loading is available Take into account the cost of bringing in a heavy load supply On large, complex sites where the permanent supply will suffice, there may be a capital charge for early installation Account must be taken for the provision of mains distribution equipment, site distribution, transformers, rising main units for taking power to working levels, lamps and the like Endorsement by either an Electrical Contractor or Professional (M&E) Engineer may be required, prior to commissioning
(9) Temporary Access Visits to the site, inspection of drawings and the BOQ will identify the line of permanent access points and the nature of construction It will then be possible to decide whether roads can be constructed at an early stage and allowance made for maintenance Alternatively, it may be preferable to lay the base and allow for making up to the proper level prior to applying the finishing layer The need for additional temporary roads will have to be assessed and the most suitable type of construction selected, paying attention to the usage/traffic expected and the nature of ground
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