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Earth Works Road Construction

Controlling Earthmoving Plant

In order to ensure that controlling earthmoving plant is used in the most economical manner the supervisor must :-

•    Work with the civil engineer to estimate the anticipated (target) out put per hour (or day or week) for each machine and earthmoving plant hours required to complete each major task.

•    Work with the quantity surveyor to estimate, from plant hire and wages etc., the cost of completion the earthwork in the programmed time using the earthmoving plant selected. Check to ensure the work can be performed within the amount provided in the estimate.

•    Study each operation carefully as it begins and check cycle times etc. to see if improvements can be made.

•    During the progress of the work, check that target outputs are being achieved by earthmoving plant.

•    Always think ahead and anticipate problems. What happens for example, if motor grader or roller breaks down ? Have an alternative plan ready.

•    Controlling earthmoving plant that Ensure plant fleet is balanced, i.e. machine capacities are matched as far as possible, e.g. loader output matches trucking capacity.

•    Always make the best use of the driver instructor.

•    Ensure that operators are properly directed by the earthmoving plant supervisor.

•    Watch  plant  operations  closely  for  faulty  techniques  and  have  these  corrected.  (Poor operating techniques can reduce output by 50%).

•    Use human relations skills to get the best out of the  earthmoving plant  operators. They are key men on the job.

•    Ensure  machines  are  not  abused.  If  a  machine  has  to  be  continually  pushed  beyond  its capacity, look for a better way of doing the job or get a better machine.

•    Check that the servicing of plant is being carried out. Discuss any problems with the  earthmoving plant  inspector.

Categories
Earth Works Road Construction

Earthworks in Road Construction

 Earthworks in road construction  can  be  defined  as  all  the  operations  involved  in  the  loosening,  removing  and depositing of earth, soil  and rock. The principal earthworks operations are :-

•    Stripping vegetation and topsoil

•    Loosening material in cutting and borrow pits

•    Excavating material

•    Loading material from cuts etc. and hauling to fills or to spoil

•    Spreading, shaping, watering, compacting and trimming the fill material.

Earthworks in road construction belong the several sections and deals with the construction of earthworks cuttings and embankments and also the cost  of  earthworks  is  a  major  part  of  the  total  job  cost,  it  is  essential  that  the  construction managers and project managers :-

(1)     has a sound knowledge of the specification requirements,

(2)     plans  and  supervises, directs  and  control ;  the  job  in  the  most  efficient  and  economical way.

(3)     gives close attention to the selection of the correct plant, and

(4)     has a sound knowledge of correct operational procedures.

The types of earthworks  plant  available, its use and its management are also required the close attention to carry job constantly.

Specification Requirements for Earthworks

Details  of  the  standard  of  work  and  the  quality  of  materials  are  contained  in  the  job specifications.  Since  the  project manager  must  always  ensure  that  the  work  for  which  he  is responsible  meets  the  standards  specified,  the  specification  requirements  must  be  fully understood.

Planning Earthworks Operation

In  order  to  obtain  satisfactory  and  economical  results  an  earthworks  job  must  be  adequately planned  by  the  consulting  engineer  and  project manager.  Broadly  speaking  planning  may  be divided into two operations, viz :

(1)     Pre-construction planning and programming which must be carried out well in advance of job  commencement  by  the  project  engineer  in  consultation  with  the  supervisor.
Though  the  engineer  is  responsible  for  drawing  up  the  works  program,  the  project manager  can  assist  him  greatly  in  this  task  by  contributing  his  knowledge  and experience.  The  consultant  will  benefit  by  becoming  thoroughly  familiar  with  the programmed plan of operations.

(2)      Construction planning  which involves the day-to-day organization and supervision of the job by the consulting supervisor.

 

Categories
Road Construction Traffic Control

Factors Affecting for Traffic Control in Road Construction Project

Factors affecting for traffic control in a construction of road project will vary  according to following conditions which are prevail.   We have to decide traffic control arrangement according to suit different conditions in  road construction project . When deciding what provisions for traffic are necessary the following factors should be considered –

•    Width  of  the  road  formation – Is  there enough room for the traffic  and  plant  to  operate safely and efficiently at the same time, can the shoulders be used for a  second traffic lane .

•    Traffic  density – How  much delay  in  construction  is the   traffic   likely  to cause  and vice versa.

•    Percentage of heavy vehicles – (remember things such as sugar or grain harvests).

•    Terrain – Shape and composition of the ground – e.g. black soil, rocky outcrops, swamps.

•    Seasonal  –  Shape  and  composition  of  the  ground  –  e.g.  black  soil,  rocky  outcrops, swamps.

•    Seasonal influences – Wet season, drought (water shortage).

•    Safety – job employees and the public.

•    Time – Comparison between alternatives.

•    Cost – Comparison between alternatives.

Above mentioned factors affecting for traffic control  in road construction project can be vary with special  situations and that should be decide to suit all the site conditions.

Categories
Project Management Road Construction

Project Appreciation of Project Management

Project appreciation is the next part of project planning which will be  the  project manager  should  discuss with the consultant engineer all aspects of the project including those things noted during the site inspection. The following factors should also receive attention :-

•    Availability of skilled and unskilled labor
•    Availability of plant and equipment
•    Availability of materials
•    Weather expected during the construction period
•    Industrial problems likely and possible corrective action
•    Work to be done by sub-contract and availability of suitable sub-contractors
•    Engineering and supervisor staff requirements like Plant Managers, Quantity Surveyor, Laboratory manager, Site managers etc. )
•    Limitations imposed by other bodies (Power Authorities, Local Authorities,  NWS & DB., Railway Department, Telecommunications etc. )
•    Availability of Public Utility service personnel to carry out service alterations.

The  Consultant Engineer and   Project manager   need  to  work  in  close  co-operation,  each  contributing his ideas, knowledge and skills to the planning operation to formulate the most likely and practical work plan.  Decisions are needed at this point to establish the details to be used in the  project program ,

•    Starting date
•    Organization to be used
•    Construction methods to be used
•    Plant, material and manpower requirements
•    Sequence to be used for job activities.

These decisions are closely related to the desired rate of construction.

Project appreciation is the structural process that analyse all the possible angles to success of the project. 

Categories
Road Construction Safety

Safety Rules of Road Construction Project

These safety rules of road construction project should be taken as conditions of employment. Every effort ought to be designed to convince the men that they are for his or her personal protection. If this should fail the safety rules ought to be enforced.

  • The first  safety rule of road construction  is barriers and/or signs should be erected and safety comes and stop/go bats were designed as  set  out  in  the  “Provision  for  Traffic”  specification  to  avoid  injury  to  workers  by passing vehicles and also the traveling public.
  •  Substantial  safety  rails,  securely  bolted,  are  to  be  erected  in  all  cases  where  it  is considered  necessary  to  provide  protection  for men against contract with, proximity to, falling previously mentioned onto or into machinery or harmful substances, or injury because of height of fall.
  • The important safety rule for road construction work should be that approved  safety  guards  are  to  be  fitted  to  all  items  of  machinery  or  plant  where practicable.  Guards  so  fitted  are  to  be  removed  or  adjusted  by  authorized  persons  only and therefore are to become inspected at regular intervals to ensure they are serviceable and afford adequate protection.
  • Safety rule for Plant operators are to :–
    1.  Walk around their machines to ensure the significant area is apparent in men and obstructions before moving off.
    2.   Ground all buckets cutting edges and so on before leaving the guarana plant for job breaks, knock-off, etc.
  • Nobody apart from the operator or authorized persons (e.g. Driver Instructor) would be to ride on plant.
  • No  employee  will  be  permitted  to  operate  designated  plant  or  machinery  or  explosive- powered tools or be the dogman, hoist driver, rigger or scaffolder unless he’s the holder of the current “Certificate of Competence” or perhaps a “Permit like a Learner”. Within the latter case the person must work underneath the supervision of the certificated man.
  • Suitable safety gear is going to be worn or used all the time, including –
    1. Safety helmets if you find danger of damage from falling or flying objects.
    2. Safety jackets when workmen might be subjected to injury risk from passing vehicles and plant.
    3. Any other components of protective equipment for example gloves, goggles, ear muffs and also the like, particularly if handling dangerous substances.

You can  read the next part of the  safety rules for a road construction jobs  by visiting to next posts.

Categories
Road Construction Traffic Control

Traffic Control During Construction

In any situation of road construction works progress, in which the motorist may be denied the safe usage of the full carriageway, some provision for traffic is essential. This road  traffic control  applies in both construction and maintenance.

The safety of the motoring public and of the job employees, is the key consideration in making adequate provision for road traffic. Both groups are entitled to equal consideration. Road Traffic may be slowed down, halted and held or diverted according to the job circumstances. However when any such action are taken, in addition to safety, public relations must be taken into consideration.

Two Lane Road Traffic Control

The Construction managers job is to all times aim at keeping at least two traffic lanes open. At least two traffic lanes should always be available during the hours of darkness. There are a number of ways of doing this

• Side tracking – A side track is defined as a specially constructed road or track by-passing an obstacle, roughly parallel to the main route, i.e. side tracks and so called detours on rural roads.

• Detouring – A detour is defined as a diversion of traffic using existing roads or streets, as in an urban situation.

• Widening and/or compacting existing shoulders to create an additional temporary traffic lane.

• Completing work each day to a stage where the job can be opened to traffic at night and weekends. As a example paving work

One Lane Road Traffic Control

The one lane road traffic are considered Where it is not practicable to keep two traffic lanes open, flagmen will always be used to control the traffic of road on the approaches to and through the job site. The some of the key factors for the use of flagmen are-

• When traffic is restricted to the use of one lane, flagmen will ALWAYS be used.

• On single lanes not exceeding 30 m in length one flagmen may be used.

• On single lanes exceeding 30 m in length two flagmen will always be used, each to be visible to the other and one to be nominated as controller. In cases where visibility between flagmen is not possible, small radio transceivers should be used. Alternatively a third flagmen, with visibility to the other two, may be used.

One lane  road traffic  is to be converted to two lanes road traffic for the hours or darkness and at weekends, when the job is unattended, i.e. the lane under construction is to be opened up.

Categories
Project Management

Site Inspection of Project Management

The next stage of project planing of project management is the site inspection. The  project documents  should be examined on the ground in relation to the site conditions, noting special features which will affect entire project progress or cost.

Some of the key factors to be considered during this site inspection are:-

• Possible camp sites and details of any alternative accommodation facilities.
• Access to the site by road and rail; rail unloading facilities.
• Access to the actual working areas.
• Disruption of private accesses.
• Alterations to utility services {Check details on plans).
• Availability of public facilities – ambulance, medical and hospital services, telephone, postal, gas stations, fuel and oil depots.
• Traffic control during construction (side tracking, detouring).
• Sources of  water  and power.

Features requiring special  attention 

(a) Grades, ground shape and stratification.
(b) Places where construction problems may occur,
– steep sloping ground
– drainage and seepage areas
– nearby  buildings  likely to be affected by job vibrations.

(c) Possibility of in-situ or nearby material suitable for:-

– selected fill,  shoulder or pavement 
– pipe bedding
– stone pitching
– side track paving.

Categories
priming Road Construction

Types of Bitumen Surface in Road

Types of bitumen surface will  depend on various type of designed where applicable. Bitumen surface in road consists of a thin (often less than 7 mm) coating of sprayed bitumen (the binder) into which is embedded a covering layer of aggregate. The bitumen surfacing will normally overlay a compacted gravel or crushed rock base which has been primed with a  cutback bitumen , although occasionally pavements may be  bitumen surfaced  without the prior applications of a primer.

The function of the cover aggregate is to resist abrasion and to transmit the wheel loads directly to the underlying pavement. The  bitumen binder  serves to hold the aggregate in position and prevents it being dislodged by the traffic.

The essential requirements of a bitumen surface are :-

• The surfacing should be hard wearing, skid resistant and smooth running.

• The surfacing should protect the underlying pavement from loss of moisture and unraveling under traffic loads.

• The surfacing should provide a high degree of waterproofing to protect the pavement from the effects of climatic changes.

Types of Bitumen Surface

The various types of bitumen surface work include :-

(1) Priming.

This consists of spraying a primer onto the compacted gravel or crushed rock base. The primer is normally bitumen which has been made more fluid called cut-back bitumen by the addition of kerosene (cutter) so that most of it will soaking. Priming is carried out to prepare the surface for the subsequent seal coat and to assist in waterproofing the pavement.

(2) Primer Seal.

This is a heavier primer which is covered with sand or fine aggregate (up to 7 mm maximum size). The sand provides a wearing surface which can carry traffic for a limited period of time (e.g. up to six months).

(3) Seal Coats.

The most common seal coat consists of a single application of bitumen (binder) which is sprayed onto the primed pavement followed by an application of aggregate which is rolled with rubber tyred rollers to embed the stone in the bitumen. The aggregate particles are all about the same size so that all the stone will protrude approximately the same amount above the surface of the bitumen.

This treatment is also used for resurfacing existing bitumen surfaced roads.Other forms of seal coats include :-

• A single application of bitumen followed by an application of coarse aggregate (e.g. 20 mm or 16 mm) followed then by an application of fine aggregate (10 mm or 7 mm).

• Two or more successive application of bitumen and aggregate in which the rates of application of the bitumen and size of the aggregate are successively reduces.

(4) Special Treatments.

Common special treatments are :-

(a) Dust Laying – the application of low viscosity (fluid) slow curing cut-back bitumen, or a diluted  bitumen emulsion  to a dusty road surface.

(b) Surface Enrichment – the light application of bituminous material, such as cut- back bitumen or diluted  bitumen emulsion  to increase the binder content. If the bitumen surface treatment is very light it is sometimes referred to as a “fog Coat”.

(c) Penetration Macadam – a course of rolled crushed aggregate grouted with bitumen.

(d) Slurry Sealing. – the application of a mixture of bitumen emulsion, water and fine aggregate to an aged and cracked road surface by a spreading box.

Slurry sealing is not strictly a sprayed treatment but is included in this course for convenience.

To achieve a satisfactory bitumen surfacing, all phase of the work, from the preparation of the pavement, through the application of primer, binder and cover aggregate, and the subsequent compaction of the aggregate by rolling, must be carefully designed and supervised.

 

Categories
Bitumen

Bitumen Types as It Usage

Types of bitumen as it usage means, these are vary with usage such as climate conditions where it apply as well as quality of the work.

it can divided in to two groups

  1. Cutback bitumen
  2. fluxed bitumen

Cutback Bitumen

Cutting is the term used when a relatively volatile material such as kerosene is added to the bitumen. The added material is called a cutter and the resulting product is termed a cutback bitumen. Between 2 and 15 percent by volume of bitumen cutter is added to the bitumen, the actual percentage depending on the climatic conditions and the size of the cover aggregate. Higher ambient temperatures and use of larger sizes of aggregate will reduce the amount of cutter needed in the mix. Also less cutter will be necessary if heavy traffic is required to travel on the work soon after it is completed.

Fluxed Bitumen

Fluxing is the term used when heavier grades of oil (e.g. diesel fuel oil) are added to the bitumen. The added oil is called a fluxing agent and the resulting product a fluxed bitumen.Fluxed bitumen are used where traffic and climatic conditions make slow curing of the binder desirable. The fluxing agent prolongs the period before serious hardening of the binder affects its performance. It is desirable that the binder remains as soft as possible, consistent with its ability to hold aggregate under the required conditions of traffic.

Curing

Loss of the volatile additive in the bitumen by exposure to air or heat is called “curing”. Cutback bitumen cure relatively rapidly. Fluxed bitumen cure very slowly. By varying the amount and relative proportion of cutter and fluxing agent and also the temperature, a wide range of curing times can be achieved.

It should be noted that although kerosene is described as a cutter, its volatility is in between that of petrol and diesolene. The lighter fractions evaporate progressively, leaving behind the heavier fractions which, being less volatile, in effect produce some fluxing effect.

There are three basic classifications for cutback and fluxed bitumen,

(1)     Rapid-Curing (RC) –  bitumen  to which highly volatile solvents such as naphtha or petrol have been added.

(2)     Medium – Curing (MC) –  bitumen  to which a solvent of medium volatility such as kerosene has been added.

(3)     Slow – Curing (SC) – bitumen to which has been added oils of low volatility such as diesoline.

Within each of the basic classifications there exists a range of grades designed to meet the particular requirements of differing work.

Categories
Project Management

Project Planning by Project Management

The road construction project planning must be carefully do so that it may be successfully carried out with regard to Quality, Time, Cost and available Resources.

The four stages of  project planning  can be identified and are:-

(1)     Study of project documents
(2)     Site inspection
(3)      Project appreciation
(4)     Preparation of a project program

STUDY OF  PROJECT DOCUMENTS

The first step of the project planning is to be study of project documents, These documents are prepared during tendering process. The original condition can be slightly  changed when constructions are are going on( overall 10% max of bidding Value). it should not be vary too much and conditions are made during the bidding stages. Project management specialist are having sound knowledge about project plannings and cost variation rather than original. you can get an idea that how to prepare contract documents for a new project.

The following document are considered as project documents

•    The Project scheme (Plans, specification, quantities, estimates)
•    The commencement date
•    The target completion date
•    Details of funds to be allocated.

It  should  be  noted  that,  during  the  design  stage,  comprehensive  materials  surveys  are often carried out on imported and in-situ materials. The purpose of this is to ensure that, as far as possible,  construction management  problems  are  foreseen  and  allowed  for  in  the  design  and  estimated and analyses by various  project management  tools for the any scale of projects.    The construction  manager or project manager should  avail  himself  of  any  such  information  before  making  the  site
inspection.

Aspects of the project requiring special attention during the site inspection should be noted.