Presentation on theme: "Sampling Methods and Quality Assurance Plan Presented by: Er. Bhagawan Shrestha."— Presentation transcript:
Sampling Methods and Quality Assurance Plan Presented by: Er. Bhagawan Shrestha
Quality Assurance Plan
Total Quality management (TQM) As defined by ISO: “TQM is a management approach of an organisation, centered on Quality, based on participation of all its members of the organisation and aiming at long-term success through customer satisfection, and benefits to all the members of the organisation and the Society”.
Elements of a Quality Assurance System for Road Project A.Assessment of Requirements of Road Project- design criteria/design life/ minimum acceptable level of riding quality – higher the standard of road, higher will be the cost. B.Choice of Quality Materials and Design – Evaluating pavement thickness and composition for the assessed traffic and subgrade conditions to meet the design riding quality
Elements of a Quality Assurance System(contd.) C. Development of technical specifications and acceptance criteria- i.Every Government/department own Standard Technical Specifications consisting of best practices of construction, selection of materials, use of equipment and acceptable criteria. ii. For new items, additional Specifications must be drawn up, based on practices elsewhere for similar works. iii. Depending upon the type of road facility and the minimum acceptable riding quality requirements, related acceptance criteria for various items of works should be set forth, based on past experience.
Elements of a Quality Assurance System(contd.) D. Choice of construction method/equipment/ plant Must meet requirement of technical specification as demanded by design criteria E.Field supervision and Quality Control of materials, construction technique, surface finish to desired profiles – Quality control is the task of : i.Inspection and testing of materials, production process and the end product ii.Measuring variations from the predetermined standards iii.Taking corrective action to minimize adverse variations and iv.Accepting or rejecting the works
Elements of a Quality Assurance System(contd.) F. Assessment of Quality of finished road- desired quality of end product has indeed been achieved G. Periodic inspection and maintenance measures – maintenance during defect liability period. A good quality assurance system covers entire life cycle period of a project.
Quality Control System Quality control system comprises methods, procedures and organization for Quality Control of works and is implemented in following sequences: i.Compliant testing for materials including laboratory trials, ii.Compliant testing for methods and equipment prior to commencement of work, including site trials or trial sections, iii.Control testing during construction (process control), iv.Acceptant testing on completed works or parts of works.
Quality Control System(contd.) Contractor carries out all necessary tests and reports to the Engineer results of such tests before submitting materials and/or finished works or part of works to Engineer for approval For satisfying himself about quality of works, quality control tests shall be carried out by Engineer himself or by any other agencies deemed fit by Engineer.
Quality Control System(contd.) Before commencement of works, Contractor demonstrates a trial run of all construction equipment for establishing their capability to achieve requirement of Specifications and tolerances to satisfaction of Engineer. Supply, testing and monitoring shall be in compliance with a Quality Assurance Plan.
General Quality control is a small part of Quality Assurance Only quality interested client group, quality interested engineering group and quality interested construction group, all of whom demand quality workmanship in engineering, procurement and construction can assure best quality of works.
General In road construction, Quality Control deals with testing materials and end products at predetermined intervals, finding their properties, judging their suitability
Quality Assurance Quality assurance (QA) is a system or program used to monitor and evaluate the aspects of a project, service or facility to determine if quality standards are being met.
Quality Assurance(contd.) Contractor assures Engineer for Quality of works so he submits Quality Assurance Plan (QAP) to Engineer for approval.
Quality Assurance Plan Quality Assurance Plan includes the following: 1.The Sequence of works (step by step) 2.Quality Control Schedule 3.List of sources of materials and of manufactured articles, their main characteristics, their identification 4.List of tests and quality control procedures to be implemented by Sub-contractors, if any, 5.Organization for Quality Control
Quality Assurance Plan (contd.) Quality Control Schedule Comprises of: Summary of test schedule and testing programme detailing list of tests for compliance, laboratory trials, construction control tests and their frequencies, tests for acceptance of completed works ( e.g. Load test, Non destructive tests for bridge construction). Summary of list of "critical" acceptance testing procedures, for equipment or parts of the works which corresponds to tasks on Critical Path according to construction Programme. Estimate of number of tests to be carried out at outside lab and mention name of lab proposed to carry out tests.
Quality Assurance Plan (contd.) Contractor implements Quality Control in compliance with approved QAP Engineer's approval of QAP not relieve Contractor from his responsibility of quality of Works to be performed as per Specifications Engineer's approval of QAP not exempt Contractor of any procedure to inform Engineer in writing or request for Engineer's approval or re- approval as specified in Conditions of Contract and/or in Specifications Contractor shall monitor and update QAP
Sample : A portion, piece, or segment that is representative of a whole. An entity that is representative of a class; a specimen. Sampling is as important as testing and every precaution shall be taken to obtain samples that will show the true nature and condition of the materials.
SAMPLING (contd.) Sampling of soils and gravels shall be carried out as specified or as directed by the Engineer. Samples shall be prepared for testing as indicated in IS 2720 part I Sampling of STONE, AGGREGATE, SAND AND FILLERS shall be carried out as per ASTM–D75 and the samples shall be prepared in accordance with IS 2386 or according to sampling procedures specified for the Standard Methods of testing given in Table 6.5.
SAMPLING (contd.) Ordinary and High Strength Portland Cement (OPC and HSPC), Portland Slag Cement (PSC), Portland Pozzolana Cement (PPC) shall be sampled according to IS 3535 and tested according to IS 4031. Limes shall be sampled and tested in accordance with BS 890 Sampling and preparation of samples of lime treated material shall be carried out as specified or as instructed by the Engineer
SAMPLING (contd.) Sampling and testing on concrete shall be carried out in accordance with the standard methods given in the Table 6.9 Sampling of straight-run and cut-back bitumens shall be carried out in accordance with ASTM D 140. Sampling of bitumen emulsion shall be carried out in accordance with BS 434, Part 1, except that where a delivery is made in drums or barrels, the number of samples shall be as indicated in AASHTO sampling method, T40 para.11.1.
SAMPLING (contd.) Sampling of Bituminous Mixtures shall be carried out in accordance with ASTM Method D 979. The sampling and frequency of testing of Reinforcing Steel shall be as set out in the NS 84-2042 and NS 191-2045. Bricks shall conform to NS-1-2035 with the exceptions specified in Sub-clause 2502(1).
SAMPLING (contd.) Mortar shall comply with IS 2250–1981; Code of Practice for preparation and use of masonry mortar. Reinforced concrete pipes shall comply with the requirements of NS 80-2042/IS 458:1988 High density polythene pipes shall comply with the requirements of NS 40-2040 Paint for road marking shall comply with NS 408-2054
SAMPLING (contd.) Precast concrete channels, kerbs, edging, quadrants and gutters shall comply with the requirements of IS: 5758 - 1984. Manhole covers and frames shall be of cast iron and shall comply with IS: 1726-1991. Cast iron gratings for drainage purposes shall comply with the requirements of IS: 5961 – 1970. All wire used in the fabrication of gabions and wiring operations during construction shall comply with the requirements of NS:169-2045. The wires shall be galvanised with heavy coating of zinc. The coating of zinc shall comply with NS:163-2045
SAMPLING (contd.) If otherwise not specified in the contract, no separate measurement and payment shall be made for sampling, samples and testing of materials, trials and construction control/process control testing. It shall be deemed to have included in the rates of the relevant items for complying with the requirements of this Section 600.
SAMPLE TAG: Project ………………………… Sample number ………….. Sampling material……………………. Depth …………… Location ………………………….. Chainage ……………… Date of sampling ……………….. Sample taken by …………………. Tests to be performed …………………………………………………..
Materials for sampling 1.Aggregates and Sand 2.Stones From Quarries 3.Bituminous Materials 4.Bituminous Paving Mixtures 5.Fresh Concrete 6.Hydraulic Cement 7.Gabion Wire 8.Soil (Disturbed) 9.Soil (Un Disturbed) 10.Reinforcing Bar 11.Fresh Mortar 12.Rock (Un Disturbed)
SAMPLING Method PURPOSE NUMBER AND MASS/QUANTITY OF SAMPLES TOOLS, CONTAINER and ACCESSORIES OBTAINING SAMPLE PRECAUTION
SAMPLING (contd.) The sampling may be done for the following purposes: – Preliminary investigation of the potential sources of supply, – Control of the product at the source of supply, – Control of the operations at the site of use, and – Acceptance or rejection of the material
SAMPLING (contd.) – To ascertain the maximum variation in characteristics which the material possesses – To represent an average of the bituminous mixtures – To ascertain the periodic variation in characteristics of the mixtures for the purpose of controlling uniformity, – To determine compliance with quality requirements of the specification by performing tests. – to collect the disturbed samples for the determination of Characteristics of the materials with indication of changes in strata.