The erstwhile Public Works Department of the Government of Maharashtra was entrusted with the execution of the infrastructure works since British regime. The departments are now divided in three parts viz. Irrigation, PWD and Water supply and are functioning in a well-established fashion. The Maharashtra Public Works Manual, Maharashtra PW Accounts Code, Standard Specifications (Red Book) and the Maharashtra PW Handbook are the best documents the system had produced. These are modified to account for the changes that are necessary due to changes in material,material properties, methods of construction and availability of new equipments. The construction infrastructure works are carried out with reference to the guidelines prescribed in the above documents. The MPW Handbook has a chapter on Quality Control of works which serves as a good tool to achieve a good quality product. The first edition of MPW Handbook was published in1876 and currently the 10th edition is in use.
Quality Control Procedures
MPW Handbook Chapter 33: Quality Control
Part-I on Cement Concrete ; part II on Earthwork. Both the volumes are detailed documents and deal with the tests to be conducted in laboratory and in field & how the results should be documented in prescribed formats and are based in a way to meet the requirements of Bureau of Indian Standards. These documents are useful in guiding the field engineers to assess the quality of work in the light of design assumptions. In addition technical circulars are issued by Government in Irrigation Department (Water Resources) from time to time to add or modify the earlier provisions. Both the Quality Control and Constructions Organisation use these handbooks and Circulars/standing instructions by Govt. The basic responsibility of maintaining good quality of works rests with the Construction engineers and the role of Quality Control is complimentary one. QC as a third party auditors has the objective of pointing out deficiencies in construction materials, execution procedures and suggesting appropriate measures to achieve desired quality of the work.This is achieved through testing of materials as well as finished products.Thus QC organisation renders all necessary guidance to the construction Engineers for achieving good quality works.
Quality assurance and recent trends
Change is a keyword that is only a constant word today. Everything is subjected to change. The origin of the concept of quality assurance is also the result of such a change and this change, as is known, has arisen from the need of customer satisfaction on quality and conformance to expected stipulations. As the need for Quality assurance was felt for irrigation works, the Govt. in Irrigation Department issued a technical circular on 1st January, 1998, which makes QC functioning more effective. The circular states that any work which costs more than Rs.3 crore or any work of canal costing more than Rs.1 crore and any embankment which is more than 3 m in height is to be started only after receiving "a go ahead" in the form of a Green card/OK card from QC Wing. The format of cards is different for earthwork and concrete.
Organisation has a network of 48 laboratories spread in --------- districts. The very purpose of the laboratories is to test construction material for deciding its suitability for design and construction purpose.
In general following Construction material tests are being carried out
- Earth work: Shear test, Hydraulic Conductivity test, proctor test, physical properties and liquid, plastic limit, shrinkage limit, swelling pressure ..........
- Cement: Fineness, Soundness, Setting time, and compressive strength.
- Fine Aggregate(Sand): Mechanical Analysis Silt bulkage, filter criteria tests.
- Coarse Aggregate(Metal): Mechanical Analysis, Flakiness index, Water absorption
- Cement Mortar: Mix design
- Cement concrete: Mix design, all
- Steel: Elongation,Tensile Strength
Intermittent Supervision is visiting the construction sit by Q.C. Engineers & carring out field test to ascertain the quality of work & to confirm the same. The Q.C.Engineer help & guide the Construction Engineers to ascertain & maintain the quality & to abide by specification.
During inspections,two types of inspection slips are used by QC wing on the site of works viz.Green and Red. Green inspection slip is used for pointing out minor defects in the work and to communicate the immediate corrections needed in on going work. While Red inspection slip is used for serious discrepancies in the work, where stoppage of works to improve/rectify construction material/procedure is mandatory. In actual procedure, Q.C. Jr.Engineer visits the site of work he issues the Green slips every day which includes conducting field tests. When there are minor deficiencies in the work, the same are written in the inspection slip alongwith test results if any and inspection slip is handed over to his construction counterpart on which construction incharge has to take action ,if needed. When there are serious deficiencies, bad workmanship. violation of specifications etc. the Red slip is issued to construction organisation for stoppage of work by the officers not below the rank of Dy.Engineer or Executive Engineer of QC organisation.Compliance of the Yellow/Green Inspection slips is to be done by construction organisation quickly and work is continued without stoppage. When Red slip is issued the work is to be stopped and can be resumed only after complying the deficiency duly accepted by the QC wing.
Whenever the works are visited by Dy.Engineer,Exexutive Engineer and by Superintending Engineer of QC organisation, the inspection Notes are issued which are based on inspection details and deficiencies / corrections suggested are to be complied with by the construction organisation.The visits are of informed as well as surprise type.
Meetings of the construction Executive Engioneers are arranged by the respective Quality Control Division Excutive Engineer to sort out quality issues and maintain the cordial relation with construction wing. These meetings help very much in solving many routine and specific problems from the both the wings.
Reporting and monitoring
The reporting of QC work is as explained here. QC Jr. Engineer sends Daily placement reports of the works to Quality Control Sub Division. The Executive Engineer, Quality Control Division prepares and submits workwise reports in three types. i.e. Monthly, Quarterly and Annual. These reports are sent to construction Superintending Engineers/Executive Engineers and to Superintending Engineer Quality Control Circle.The monthly,Quarterly and Annual Q.C. reports include number of various laboratory /Field/record tests conducted for concrete/masonry/earth work along with actual frequency achieved, achievement of criteria, statistical analysis of tests, results of compressive strength of cubes for concrete/masonry work, graphs of statistical analysis of earth work.The Quarterly statistical data for concrete/masonry work include the number of tests actually conducted, percentage of tests achieving specified strength, Standard Deviation and co-efficient of variation etc. This report is scrutinised in the Quality Control Circle, and details of works which do not satisfy the specified criteria are reported to the Executive Director, Superintending Engineer and Chief Engineer of construction wing to improve the quality of these works. The copy of the report is given to Govt.also.