Durability of concrete may be defined as the ability of concrete to resist weathering action, chemical attack, and abrasion while maintaining its desired engineering properties. Workability in concrete defines its capacity to be placed, consolidated, and finished without harmful segregation or bleeding. Concrete is a most widely used construction material, commonly made by mixing of cement with fine aggregate, coarse aggregate, water and admixture. Unworkable concrete needs more work or effort to be compacted in place, also. Acronyms aashto american association of state highway and transportation officials aci american concrete institute. Top 6 important quality tests of concrete quality assurance.
Quality control in concrete construction work civilblog. Chapter 1 components of concrete concrete is made up of two components, aggregates and paste. Increasing the water content of the mix for easier workability without increasing the cement. Pdf a study on the quality control of concrete production. Preparation guidelines for quality manual for ready mixed concrete companies february 2008 prepared by. Pdf a study on the quality control of concrete production in.
Workability of concrete is a broad and subjective term describing how easily freshly mixed concrete can be mixed, placed, consolidated and finished with minimal loss of homogeneity. Webbased quality control is one of the most effective ways for this purpose. If two or more admixtures are used simultaneously in the same concrete mix, data should be obtained to assess their interaction and to ensure their compatibility. Quality management system for ready mixed concrete companies part a. This guide is not intended to restrict the use of new or innovative quality control practices or testing. Quality assurance and quality control iowa state university. Download file pdf quality control in civil engineering. Durability of concrete types of durability and factors. This leads to elucidation of problems surrounding the topic of workability and to an account of the potential for quality control. If not, then water that is for concrete bonding will evaporate and henceforth concrete strength drops.
In the united kingdom, the standards specify a slump cone height of 300 mm, a bottom diameter of 200 mm and a top diameter of 100 mm. Workability of concrete mixture is measured by, veebee consistometer test, compaction factor test, and slump test. Workability and quality control of concrete pdf free download. Workability is one of the physical parameters of concrete which affects the strength and durability as well as the cost of labor and appearance of the finished product. It is not a suitable method for very wet or very dry concrete. The workability, compressive strength and the slump loss of concrete with an without the use of admixtures shall be established during the trial mixes before use of admixtures. It increases the workability of the concrete and lowers the need for water content by 1530%. Workability and quality control of concrete the word workability is a term that refers to properties of fresh concrete, that is, of the concrete before it has set and. They contribute significantly to the quality of the concrete. The quality control of concrete is the most important issue in achieving its desired strength and durability. The use of such technologies enables companies to be more.
Compared to insitu concrete, rmc ensures better quality control of the concrete, more thorough mixing of the ingredients and better uniformity between batches. The benefit of a good qa program far outweighs the costs for both the agency and contractors. Workability is a property that directly impacts strength, quality, appearance, and even the cost of labor for placement and. Therefore, a performancebased concrete quality control during concrete construction with documentation of achieved construction quality and compliance with the specified durability should also be. This document summarizes the principles of quality control.
Quality management plan guidance for concrete used for construction of significant features. This talks about the preparation to the proper filling of concrete cylinders or molds, to the compaction of concrete, the ways to level the concrete surface, the curing itself up to the proper way of transporting these test specimens. Aug 29, 2010 quality control of concrete on site part 1 federal highway administration 1994 video vh274 tests for onsite quality verification of concrete are demonstrated in this series of four tapes. Oct 04, 2016 workability of concrete is an important property of concrete while concrete is in its fresh state. Quality control of concrete on site part 2 federal highway administration 1994 video vh274 tests for onsite quality verification of concrete are demonstrated in this series of four tapes. Aug 14, 20 this leads to elucidation of problems surrounding the topic of workability and to an account of the potential for quality control. Workability and quality control of concrete the word workability is a term that refers to properties of fresh concrete, that is, of the concrete before it has set and hardened, and it is legitimate to ask why any attention. Quality of concrete can also be further assessed by giving a few tappings or blows by tamping rod to the base plate. In order to achieve scc workability and realize the associated benefits, the materials and mixture proportions must be properly selected and the concrete quality must be carefully controlled. This is to ensure that all the concrete supplied shall be in accordance with these requirements and with the specifications that has formed the basis of the agreement between the producer and purchaser. Mar 28, 2018 this talks about the preparation to the proper filling of concrete cylinders or molds, to the compaction of concrete, the ways to level the concrete surface, the curing itself up to the proper way of transporting these test specimens. Quality management plan guidance for concrete used for. However, there are a number of issues associated with poor handling and curing of ready mixed concrete.
Therefore slump test or compaction factor test should be performed to check workability of concrete. Workability of concrete factors affecting workability of. Concrete quality control curing concrete engineering intro. Many conventional methods have been developed for the quality control of precast concrete. Workability and quality control of concrete crc press book. Mar 22, 2018 factors affecting workability of concrete a concrete is said to be workable if it is easily transported, placed, compacted and finished without any segregation. Concrete is a mixture of cement, water and aggregate. Workability of concrete is defined as the ease and homogeneity with which a freshly mixed concrete or mortar can be mixed, placed, compacted and finished. The ability of concrete to withstand the conditions for which it is designed without deterioration for a long period of years is known as durability. This post describes the 3 primary stages involved in quality control in concrete construction work such as qc before concreting, qc during concreting etc.
A slump test can be used to measure the workability of concrete. Specification and quality control of light weight foam concrete. Workability and quality control of concrete engineering books. Sep 02, 2003 fresh concrete must be produced with the properties required for its intended applications, for example, it must be workable enough to flow into formwork, and to be compacted. En 2061 concrete specification, performance, production, and conformity en 450 fly ash for concrete definitions, requirements and quality control en 9342 admixtures for concrete definitions and requirements en 1008 mixing water for concrete en 123501 testing fresh concrete.
Therefore slump test or compaction factor test should be performed to check workability. Factors affecting workability of concrete a concrete is said to be workable if it is easily transported, placed, compacted and finished without any segregation. Regardless of the projects size or importance, field quality control is necessary. Concrete is said to be workable when it is easily placed and compacted homogeneously i. Durability of concrete transportation research board. Workability of concrete is an important property of concrete while concrete is in its fresh state. Inspection manual for selfconsolidating concrete in precast. Easy to use as an excel spreadsheet but powerful as a real database, its the ultimate tool to keep track of the quality of your concrete production. Quality tests on concrete are performed as a part of quality control of concrete structures. Test for workability of concrete slump cone the ease with which one can use concrete is called. The validity and limitations of standard methods of workability assessment are fully considered and there are several chapters on the effects on workability of the properties and proportions of mix constituents. The density of foam concrete generally varies from 8001600kgm3.
Concrete that is stiff or dry may be difficult to handle, place, compact, and finish and, if not constructed properly, will not be as strong or durable when finally hardened. The concrete slump test is known as standard test method for slump of hydrauliccement concrete and carries the code astm c 143 or aashto t 119. Fresh concrete must be produced with the properties required for its intended applications, for example, it must be workable enough to flow into formwork, and to. Workability is affected by aggregate gradation, particle shape, proportioning of aggregate, amount and qualities of cementitious materials, presence of entrained air, amount and quality of high range. Concrete quality control i t has been said that quality control qc does not matter once the project specifications have been satisfied.
Concrete quality control is not just during the manufacturing of the concrete. Durability of concrete may be defined as the ability of concrete to resist weathering action, chemical attack, and abrasion while maintaining its. Codewriting organizations, such as the american society for testing and materials, the american concrete institute aci, and the american association of state highway and transportation of. Pdf controlling the quality of fresh concrete a new approach. This book deals with the measurement of the flow properties. This book deals with the measurement of the flow properties of fresh concrete and the factors which affect its workability.
Best practices for concrete pavements effective quality. Workability and quality control of concrete crc press book fresh concrete must be produced with the properties required for its intended applications, for example, it must be workable enough to flow into formwork, and to be compacted. Workability of concrete is an important property of concrete while concrete is in its. Quality control of concrete on site part 1 federal highway administration 1994 video vh274 tests for onsite quality verification of concrete are demonstrated in this series of four tapes. Aug 29, 2010 quality control of concrete on site part 2 federal highway administration 1994 video vh274 tests for onsite quality verification of concrete are demonstrated in this series of four tapes.
See chapter 3 concrete testing workability is affected by. What are different tests for concrete quality check. Quality control of concrete on site part 2 youtube. Pdf ken w dayconcrete mix design, quality control and. The deformation shows the characteristics of concrete with respect to tendency for segregation. Control cylinders should indicate the desired test age. Qc has been treated as a cost center, with not much thought as to how it can benefit the bottom line of the ready mixed concrete company. What are the factors affecting workability of concrete. Pdf traditionally, the slump test has been used to measure concrete consistency.
A centralmix plant offers more accurate control of the concrete quality through. If not, then water that is for concrete bonding will evaporate and henceforth concrete strength drops down from the specified value. Fine and coarse aggregate of a predetermined quality is added to the cementwater paste in the batch to give bulk to the batch. The statistical production control screen is the musthave tool for every production and quality control manager. Quality management system for ready mixed concrete.
Workability and quality control of concrete g h tattersall. The production of concrete at each plant shall be systematically controlled. Fresh concrete must be produced with the properties required for its intended applications, for example, it must be workable enough to flow into formwork, and to be compacted. Pdf the quality control of concrete is the most important issue in.
Strictly, it is the amount of useful internal work necessary to produce 100% compaction. The quality of the product is tremendously important for the structural safety. Aci manual of concrete inspection reported by aci committee 311 aci 311. Further quality of foam concrete is depending upon the quality and type of foam is used. About three tests should be carried out for every 25 m 3 of concrete. Goti concrete technology quality control of concrete 2. This standard is important for engineers to know the ways to prepare, safe keep, and handle concrete specimens. Fresh concrete tests 231 10 12 changing concepts 236 12. Highstrength concretes may be produced with innovative materials and procedures not covered in this guide. The principal aim of the study was to investigate the existing practices on the quality. Workability and quality control of concrete by g h tattersall.
Concrete is a composite material composed of fine and coarse aggregate bonded together with. It is apparent that workability depends on a number of interacting factors such as water content, aggregate type and grading, aggregate to cement ratio, kind and dosage of superplasticizers. Quality control of concrete on site part 1 youtube. Concrete quality control test at site slump test the slump test is a means of assessing the consistency of fresh concrete. This tech brief looks at the elements needed to implement an effective quality assurance qa program for concrete paving operations. The paste is composed of cement, water, and entrained air and ordinarily constitutes 20 to 40 percent of the total volume. This booklet is a successor to the authors hugely profitable workability of concrete released in 1976 and, back, is written particularly for practicing engineers and concrete technologists. Jul 11, 2012 concrete quality control is not just during the manufacturing of the concrete. Therefore, a performancebased concrete quality control during concrete construction with documentation of achieved construction quality and compliance with. Quality of concrete construction on site can be accomplished in three distinct stages. This guide is not intended to restrict the use of new or innovative quality control practices or testing methods as they become available or necessary. Additional information on workability and quality of concrete can be obtained by observing the manner in which concrete slumps.
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