Task 1a: (LO 1: 1.1)Use of earthmoving equipmentTrenchersA trencher is a piece of construction equipment used to dig trenches, especially for pipes or cables, for installing drainage, or in preparation for trench warfare. Trenchers come in different sizes and may use different digging implements, depending on the required width and depth of the trench and the hardness of the surface to be cut. Trenchers must be handled with extreme care as they are very dangerous equipment. There are four types of trenchers that wheel trenchers, chain trenchers, micro trenchers and portable trenchers.

Wheel trenchersA wheel trencher or rock wheel is composed of a toothed metal wheel. It is cheaper to operate and maintain than chain-type trenchers. It can work in hard or soft soils, either homogeneous (compact rocks, silts, sands) or heterogeneous (split or broken rock, alluvia, moraines). This is particularly true because a cutting wheel works by clearing the soil as a bucket-wheel does, rather than like a rasp (chain trencher). Consequently it will be less sensitive to the presence of blocks in the soil. They are also used to cut pavement for road maintenance and to gain access to utilities under roads. Chain trenchersThe chain trencher is used for digging wider trenches (telecommunication, electricity, drainage, water, gas, sanitation, etc.) especially in rural areas. The excavated materials can be removed by conveyor belt reversible either on the right or on the left side. Micro trenchersWith a micro trencher, the structure of the road is maintained and there is no associated damage to the road. Owing to the reduced trench size, the volume of waste material excavated is also reduced. Micro trencher is used to minimize traffic or pedestrian disturbance during network laying. A micro trencher can work on sidewalks or in narrow streets of cities, and can cut harder ground than a chain trencher, including cutting through solid stone. They are also used to cut pavement for road maintenance and to gain access to utilities under roads. Portable trenchersLandscapers and lawn care specialist can use a portable trencher to install landscape edging and irrigation lines. These machines are lightweight (around 200 pounds) and are easily maneuverable compared to other types of trenchers. The cutting implement may be a chain or a blade similar to a rotary lawn mower blade oriented so that it rotates in a vertical plane.BulldozersThe term bulldozer has changed greatly in its meaning over the years. Bulldose a long time ago meant anything from a large dose of medicine to a pistol and its maker. In the late 1800s a slight variation of the term bulldoze, bulldozer meant using force to push through any obstacle. At first the bulldozer that we know today was called a bull grader, it wasnt till the 1930s that the name bulldozer was widely accepted as the name of the machine.The bulldozer's primary tools are the blade and the ripper. The bulldozer blade is a heavy metal plate on the front of the tractor, used to push objects, and shove sand, soil and debris. Blades can be fitted straight across the frame, or at an angle.Due to these characteristics, bulldozers are employed to remove debris, obstacles, clear roads, bushes, and trees. Bulldozers can also be used to dig trenches, farming works, and even military operations. The second major component of a bulldozer is the blade, which is the heavy metal plate at the front. It is used to shove objects, soil, sand, and debris.Wheel Loaders

A wheel loader consists of an articulated main frame that supports a front end attachment, and a cab and engine compartment with transmission at the rear end. Wheel loader, by design, are extremely versatile in scrap applications. They can be used as a carrier for implements such as shovel bucket, fork lift tines, or grapple.Wheel loaders are used mainly for loading materials into trucks, laying pipe, clearing rubble, and digging. A loader is not the most efficient machine for digging as it cannot dig very deep below the level of its wheels, like a backhoe can. In construction areas wheel loaders are also used to transport building materials - such as bricks, pipe, metal bars, and digging tools - over short distances. Front loaders are commonly used to remove snow especially from sidewalks, parking lots, and other areas too small for using snow ploughs and other heavy equipment. They are sometimes used as snow ploughs with a snow plough attachment but commonly have a bucket or snow basket, which can also be used to load snow into the rear compartment of a snow ploughs or dump truck.Dump TrucksA dump truck is a large-engine truck with a deep, open bed in the back that can be filled with items to transport. Dump trucks can come in handy for several uses, including cleaning out your home before moving, cleaning up a construction site, or moving materials like lumber, scrap metal or rubble.Construction projects are one of the most common uses for dump trucks. These trucks can fulfill a number of functions at a construction site, including hauling in the building materials then hauling out any torn down parts. The large, sturdy tires of the dump truck makes it ideal for construction sites as well, as the tires will withstand sharp nails and debris that could be harmful on regular-grade tires.A dump truck's deep bed makes it a natural transporter for materials for projects like gardening or redecorating. Heavy bags of soils and large furniture like sofas or mattresses are easily moved from vendor to buyer with a dump truck, and a rented dump truck with professional driver can be a clever solution if you have a large haul and aren't sure how to get it where it needs to go.

Task 1b: (LO 1: 1.2)Deep Excavations Methods. The basement excavation is at least 6m which produces several health and safety concerns. The sides and embankments of the trench need to be supported to protect employees operating below ground level. The water table is at least 5m therefore the employer has to take care the safety of employees. It is also required to support safety measures for controlling water within the excavated design. A series of issues are encountered during the construction such as:1. sheet pilling system2. drainage3. safe working area4. cuttings 5. embankmentsSheet Piles Sheet piles provide safety against collapse in a battered excavation. According to the soil test, the ground is loose and unbalanced without support. Sheet piles is the most suitable for supporting loose ground condition as it is a range of interconnecting steel sheets which can be positioned before or after excavation. It is recommendation that sheet piles are driven with a pilling rig before excavation to a depth of at least 1m thick before the raft foundation. The extra meter supports a cantilever and additional safety for employees before props and walling are connected to arrange maximum backing to the sheet piles. The working platform is also provided around the basement walls for safe working area and productive activities in deep excavation. Therefore, the sheet pile will be placed outside the walls for employees working in the excavation process.Drainage We have necessary to provide drainage measures to direct ground water in and out of the excavation. We need to avoid water entering into the excavation by using the drainage method. We have to excavate a sump at the lowest point of the excavation and use a pump to take out the ground water. By using this type of drainage method, we can reduce the ground water level in excavation.Working area Working area is to be excavated around the basement walls to make available room for the basement construction. This area is installed with a drain at the base of the walls after the construction. The backfill with excavated soil.Cutting Design of cutting shall provide for excavation of material within the limits of the batters including benching and terracing of cut batters, cleaning of batter surfaces, treatment of cutting floors, and foundation treatment below the embankment. Cutting is both soil and rock should provide a stable, safe foundation for the structure. Benching in cutting will be provided in both soil and rock as necessary.Embankments Embankment materials shall comply with engineering specification earthworks materials. Embankments are earthfill or rockfill structures above an existing and excavated surface to create the rail track formation.

Task 1c: (LO 1: 1.3)The safety arrangements of excavation for ground stability and ground waterGround water is water which is held in soil, either in a non-saturated, saturated or over-saturated form. Water table is a line showing the change of water content in soil. Below which soil is saturated with water. Ground water can be kept out either permanently such as for long term waterproofing for a basement, or temporarily such as to ease work during excavation.The following provisions can contribute certain degree of water-tightness to the basement during the construction: 1. .Sheet piling 2. Diaphragm walls 3. Suitable grouting to the sub-soil In addition, ground water can be further control by the use of the following arrangement: 1. Sump pumping 2. Well point systems 3. Shallow or deep-bored wells 4. Horizontal ground water control 5. Electro-osmosis methodSheet PilesSheet piles provide safety against collapse in a battered excavation. According to the soil test, the ground is loose and unbalanced without support. Sheet piles is the most suitable for supporting loose ground condition as it is a range of interconnecting steel sheets which can be positioned before or after excavation.

Diaphragm wall Diaphragm wall is a continuous wall constructed in ground in to facilitate certain construction activities, such as: As a retaining wall As a cut-off provision to support deep excavation As the final wall for basement or other underground structure (e.g. tunnel and shaft) As a separating structure between major underground facilities As a form of foundation (barrette pile rectangular pile)Diaphragm wall is a reinforced concrete structure constructed in-situ panel by panel. The wall is usually designed to reach very great depth, sometimes up to 50m, mechanical excavating method is thus employed. Typical sequence of work includes: Construct the guide wall Excavation to form the diaphragm wall trench Support the trench cutting using bentonite slurry Inert reinforcement and placing of concrete to form the wall panelGrouting Grouting is often use to stop the penetration of water in sub-soil with high permeability, such as in fissured and jointed rock strata. Row/s of holes are bored on the soil and, usually cement grout, are injected under high pressure. The cement grout will penetrate into the voids of the sub-soil and form somewhat an impermeable curtain vertically separating the ground water. Cement grout is usually a mixture of cement and water, or cement and sand under ratio maximum 1:4. Sometimes chemical grout can be used to form a gel which can increase strength and reduce permeability of soil.

Task 2a (LO 2: 2.1 and 2.2)Methods of constructing complex foundationsA shallow foundation is often selected when the structural load will not cause excessive settlement of the underlying soil layers. In general, shallow foundations are more economical to construct than deep foundations.Pad foundationsPad foundations are used to support an individual point load such as that due to a structural column. They may be circular, square or rectangular. They usually consist of a block or slab of uniform thickness, but they may be stepped or hunched if they are required to spread the load from a heavy column. Pad foundations are usually shallow, but deep pad foundations can also be used.Strip foundations Strip foundations are used to support a line of loads, either due to a load-bearing wall, or if a line of columns need supporting where column positions are so close that individual pad foundations would be inappropriate.

Raft foundations Raft foundations are used to spread the load from a structure over a large area, normally the entire area of the structure. They are used when column loads or other structural loads are close together and individual pad foundations would interact. A raft foundation normally consists of a concrete slab which extends over the entire loaded area. It may be stiffened by ribs or beams incorporated into the foundation. Raft foundations have the advantage of reducing differential settlements as the concrete slab resists differential movements between loading positions. They are often needed on soft or loose soils with low bearing capacity as they can spread the loads over a larger area.

Deep FoundationDeep foundations are those founding too deeply below the finished ground surface for their base bearing capacity to be affected by surface conditions, this is usually at depths >3 m below finished ground level. They include piles, piers and caissons or compensated foundations using deep basements and also deep pad or strip foundations. Deep foundations can be used to transfer the loading to a deeper, more competent strata at depth if unsuitable soils are present near the surface. Piles are relatively long, slender members that transmit foundation loads through soil strata of low bearing capacity to deeper soil or rock strata having a high bearing capacity. They are used when for economic, constructional or soil condition considerations it is desirable to transmit loads to strata beyond the practical reach of shallow foundations. In addition to supporting structures, piles are also used to anchor structures against uplift forces and to assist structures in resisting lateral and overturning forces. Piers are foundations for carrying a heavy structural load which is constructed insitu in a deep excavation. Caissons are a form of deep foundation which are constructed above ground level, then sunk to the required level by excavating or dredging material from within the caisson. Compensated foundations are deep foundations in which the relief of stress due to excavation is approximately balanced by the applied stress due to the foundation. The net stress applied is therefore very small. A compensated foundation normally comprises a deep basement.Techniques used in installation of pilling systemDropping weightThe dropping weight or drop hammer is the most commonly used method of insertion of displacement piles. A weight approximately half that of the pile is raised a suitable distance in a guide and released to strike the pile head. When driving a hollow pile tube the weight usually acts on a plug at the bottom of the pile thus reducing any excess stresses along the length of the tube during insertion. Variants of the simple drop hammer are the single acting and double acting hammers. These are mechanically driven by steam, by compressed air or hydraulically. In the single acting hammer the weight is raised by compressed air (or other means) which is then released and the weight allowed to drop. This can happen up to 60 times a minute. The double acting hammer is the same except compressed air is also used on the down stroke of the hammer. This type of hammer is not always suitable for driving concrete piles however. Although the concrete can take the compressive stresses exerted by the hammer the shock wave set up by each blow of the hammer can set up high tensile stresses in the concrete when returning. This can cause the concrete to fail. This is why concrete piles are often prestressed. Diesel hammerRapid controlled explosions can be produced by the diesel hammer. The explosions raise a ram which is used to drive the pile into the ground. Although the ram is smaller than the weight used in the drop hammer the increased frequency of the blows can make up for this inefficiency. This type of hammer is most suitable for driving piles through non-cohesive granular soils where the majority of the resistance is from end bearing.Vibratory methods Vibratory methods can prove to be very effective in driving piles through non cohesive granular soils. The vibration of the pile excites the soil grains adjacent to the pile making the soil almost free flowing thus significantly reducing friction along the pile shaft. The vibration can be produced by electrically (or hydraulically) powered contra-rotating eccentric masses attached to the pile head usually acting at a frequency of about 20-40 Hz. If this frequency is increased to around 100 Hz it can set up a longitudinal resonance in the pile and penetration rates can approach up to 20 m/min in moderately dense granular soils. However the large energy resulting from the vibrations can damage equipment, noise and vibration propagation can also result in the settlement of nearby buildings.

Task 2b (LO 2: 2.3)Constructions methods used in utilities Existing utility services to adjacent properties are normally accommodated during the acquisition of new right of way for a project. The RUS/Utility Coordinator needs to work with the Right of Way Agent to determine how the existing service will be maintained. RestorationWhere highway construction disrupts a utility service to a residence or business located outside the area acquired for new right of way, the restoration of that service is eligible for reimbursement. Where highway construction disrupts a utility service to a residence or business located wholly or partially within the area acquired for new right of way, the cost of relocating the service is included in the property settlement and the utility is not eligible for reimbursement. RemovalThe removal of utility facilities which are located on and serve property purchased for new right of way are reimbursable only if the utility company has a valid property right in the existing location. When the utility company does not have a valid property right, the landowner has the option of requiring the utility to remove their facilities at the utilitys cost when the landowner no longer requires the service. The State purchases that landowners right when they purchase the property for right of way purposes.Constructions methods used in drainageDrainage can be either natural or artificial. Many areas have some natural drainage; this means that excess water flows from the farmers' fields to swamps or to lakes and rivers. Natural drainage, however, is often inadequate and artificial or man-made drainage is required. There are two types of artificial drainage Surface drainage Subsurface drainage.Surface DrainageSurface drainage is the removal of excess water from the surface of the land. This is normally accomplished by shallow ditches, also called open drains. The shallow ditches discharge into larger and deeper collector drains. In order to facilitate the flow of excess water toward the drains, the field is given an artificial slope by means of land grading.

Subsurface DrainageSubsurface drainage is the removal of water from the root zone. It is accomplished by deep open drains or buried pipe drains. i. Deep open drains The excess water from the root zone flows into the open drains. The disadvantage of this type of subsurface drainage is that it makes the use of machinery difficult. ii. Pipe drains Pipe drains are buried pipes with openings through which the soil water can enter. The pipes convey the water to a collector drain. Drain pipes are made of clay, concrete or plastic. They are usually placed in trenches by machines. In clay and concrete pipes (usually 30 cm long and 5 - 10 cm in diameter) drainage water enters the pipes through the joints. Flexible plastic drains are much longer (up to 200 m) and the water enters through perforations distributed over the entire length of the pipe.

Constructions methods used in brick culvertThere are two major classes of culvert installations, based upon the conditions that influence loads: 1. Trenched, where culverts are placed in natural ground or compacted fill with a controlled trench width 2. Embankments, where culverts are usually placed in natural ground but are covered by a constructed embankmentTrenchedTrench installations are made in relatively narrow excavations on a carefully prepared bedding to distribute the load and the culvert is covered with earth backfill that extends to the ground surface. For flexible culverts, a well-compacted soil envelope of adequate width is needed to develop the lateral pressures required to maintain the shape of the culvert. The width is a function of the strength of the surrounding in-situ soil and the size of the pipe. The backfill load ultimately transmitted to the pipe is a function of the trench width. With rigid culvert placement, the determination of the backfill load is based on the trench width and a pipe strength is selected to withstand that load.EmbankmentsCulverts placed in an embankment are usually bedded in natural ground and are overlaid by a constructed embankment. The required supporting strength of a buried pipe is determined by the total load that is imposed upon the pipe. The magnitude of the load is influenced by the uniformity and stability of the support soil, as well as conditions around and over the pipe. However, the load-carrying capability of rigid culverts is essentially carried by the structural strength of the pipe itself since rigid pipe is stiffer than the surrounding soil. A well-compacted soil envelope is required to develop the lateral pressures necessary to maintain the shape of flexible culverts.

Task 3a (LO 4: 4.1)RISK ASSESSMENT FOR EXCAVATIONNoWork ActivityHazardPositiveAccidentExistingRiskControlSeveritylikelihoodRisk level

AdditionalRisk controlSeveritylikelihoodRisk level

1.ExcavationsCave-inInjury or death to person(s)Damage of property

with the protective system5315maintain materials and equipment used for protective systems

5210

Personalinjury

Injury or death to person(s)Damage of propertyMaintain communication, follow methodstatement, be aware of first aid box,

5210first aidrepresentatives, contact main office525

FireInjury or death to person

Damage the underground systemPlanning the workUsing cable plansCable locating devices

5210using the experience workers

Wearing PPE

Safe digging practices515

2.Driving of piling head

ChemicalInjury or dead to personand poisonUse of appropriate PPE326site set up in line with healthand safety guidance for working on contaminated sites313

Noise

people who work near that machine may loss hearingusing construction phase plan

wear the hearing protection to prevent from this noise5210supervisor and H&S manager have to monitor and talk to the site manager if noisy workwork does start close by

515

Task 3b (LO 4: 4.2 and 4.3)Discussion about construction (Design and Management) Regulation 2007ClientThe client is the person for whom the project is carried out. The client controls the duration, budget and appointment of other parties. As such they play a key role in the systematic approach to health and safety management in construction.Client must ensure that:- Designers, contractors and other team members that they appoint, are competent, adequately resourced and are appointed early enough for the work they have to undertake They allow sufficient time for each stage of the project, from concept onwards They co-operate with others concerned in the project as necessary, to allow other duty holders to comply with their duties under the Regulations They co-ordinate their own work with others involved in the project in order to ensure the safety of those carrying out the construction work and others who may be affected by it There are reasonable management arrangements in place throughout the project to ensure that construction work can be carried out, so far as is reasonably practicable, safely and without risk to health Contractors have made arrangements for suitable welfare facilities to be provided from the start and throughout the construction phase Any fixed workplaces (e.g. offices, shops, factories, schools) which are to be constructed, will comply in respect of their design and the materials used, with any requirements of the Workplace (Health, Safety and Welfare) Regulations 1992 Relevant information likely to be needed by designers, contractors, or others, to plan and manage their work, is passed to them in order to comply with Regulation 10. Coordinators The role of the CDM coordinator is to provide the Client with a key project advisor in respect of construction health and safety risk management matters.They should assist and advise the Client on the appointment of competent contractors and the adequacy of management arrangements; ensure proper coordination of the health and safety aspects of the design process; facilitate good communications and co-operation between project team members and prepare the health and safety file.CDM Coordinators must: Give suitable and sufficient advice and assistance to Clients in order to help them comply with their duties, in particular The duty to appoint competent designers and contractors and The duty to ensure that adequate arrangements are in place for managing the project; Notify the HSE about the project Co-ordinate design work, planning and other preparation for construction where relevant to health and safety Identify and collect the pre-construction information and advise the Client if surveys need to be commissioned to fill significant gaps Promptly provide in a convenient form to those involved in the design of the structure and to every contractor (including the Principal Contractor) who may be, or has been appointed by the Client, such parts of the pre-construction plan that may be relevant to each Manage the flow of health and safety information between Clients, designers and contractors Advise the Client on the suitability of the initial construction phase plan and the arrangements made to ensure welfare facilities are on site from the start Produce or up-date, a relevant, user friendly health and safety file suitable for future use, at the end of the construction phase.DesignersIn CDM 2007, designer covers persons who prepare drawings, design details or specify a particular construction method or material. Therefore, by default anyone involved is a potential designer, including the client, architect, engineers, surveyors, service designers, project managers, landscape architects, contractors, interior designers and shop fitters and anyone purchasing materials without a detailed specification.Designers Should: Make sure that they are competent and adequately resourced to address the health and safety issues likely to be involved in the design Check that Clients are aware of their duties When carrying out design work, avoid foreseeable risks to those involved in the construction and future use of the structure and in doing so, they should eliminate hazards (so far as is reasonably practicable, taking account of other design considerations) and reduce risks associated with those hazards that remind) Provide adequate information about any significant risks associated with the designer) Co-ordinate their work with that of others, in order to improve the way in which risks are managed and controlled.Principle ConstructorThe principal contractor develops a health and safety plan from the pre-construction information provided by the CDM coordinator and by ensuring that the plan is followed. The principal contractor must be a licensed contractor. A contractor performs/manages construction work and is formally appointed by the client. The principal contractor must also comply with the contractor's duties (below). The principal contractor has prime responsibility for safety and health during the construction phase only on notifiable projects.Principal Contractors must: Satisfy themselves that Clients are aware of their duties which a CDM coordinator has been appointed and the HSE notified, before they start work Make sure that they are competent to address the health and safety issues likely to be involved in the management of the project Ensure that the construction phase is properly planned, managed and monitored, with adequate resources and competent site management appropriate to the risk and activity Ensure that every contractor who will work on the project is informed of the minimum amount of time which they will be allowed for planning and preparation, before they begin work on site Ensure that all contractors are provided with the information about the project that they need to carry out the work safely and without risks to health.Contractors and self-employeesContractors and self-employees must- Check that a CDM coordinator has been appointed and the HSE notified before they start work on site Co-operate with the Principal Contractor, CDM coordinator and others working on the project, or adjacent sites Tell the Principal Contractor about risks to others created by their work Provide details to the Principal Contractor of any contractor whom he engages in connection with carrying out the work Comply with any reasonable directions from the Principal Contractor and with any rules in the health and safety plan Inform the Principal Contractor of any problems with the plan, or risks identified during their work that have significant implications for the management of the project Tell the Principal Contractor about accidents and dangerous occurrences Provide information about the health and safety file.