Research Proposal Contents 1)
Introduction
2
2)
Problem statement
3
3)
Problem justification
3
4)
Significance of the project
4
5)
Scope of the project
4
6)
Objectives
4
7)
Literature review
5
7.1
Quality controlling of aggregates
5
7.1
Tests used for quality checking of aggregates
5
7.3
Correlations between tests
5
8)
Conceptual Framework
6
9)
Hypothesis
7
10)
Research Methodology
8
11)
Research Strategy
8
12)
Collection of data
8
12.1
Selecting Quarry sites
8
12.2
Collecting rock samples
8
12.3
Preparation of samples for testing.
8
12.4
Performing tests
9
12.5
Data analysis
9
12.6
Validation of the results
9
13)
Conclusion
9
14)
References
10
1
Research Proposal 1.
Introduction
Now Sri Lanka is in a transitional period as the country is on the path to the development after eradicating the civil war which lasted for nearly 30 years. With the development, new large scale constructions are being constructed such as High ways, Dams, Bridges and Buildings. For every such civil engineering construction, aggregate is a major requirement, so aggregate industry has become a prominent industry in Sri Lanka.
There are lots of quarries related with aggregate production in western province and those are the sources of aggregates for the above mentioned ongoing projects. When aggregates are ordered from a quarry, the quality of the aggregate has a greater importance, because aggregates play a major role in construction of highways, rigid concrete structures, and flexible asphalt pavements. This research is mainly focused on the cost reduction of quality control of the aggregates of quarries in the western province. It will be a great assistance for ongoing projects to order high quality aggregates. Quality control is not only about production but also about delivering of a quality product. Also it’s important to have strong communication among involved parties especially in the current economic climate.
According to the environment impact assessment of Colombo southern harbor development project, which is a major development activity ongoing in Sri Lanka at the moment, about 450,000 tonnes of aggregates will be required over 3 years( Sri Lanka Ports Authority, July 2006) . For the quality checking of these aggregates, contractor of the project has installed a test laboratory with the cost of Rs. 200,000.00 per month. These figures give us a clear picture of demand for the aggregate and the cost related to quality controlling of it
In the aggregate industry there are several tests which are used to check the quality of the product. Loss Angele’s abrasion value test, aggregate impact value test, flakiness index test, ten percent fine value and sieve analysis are the tests which are done for aggregate samples. Among them Loss Angele’s abrasion value and the aggregate impact value are the parameters which indicate the crushing and impact resistance of aggregate samples. Other than those tests, to determine the strength of the rock, unconfined compressive strength, point load index and Smitdth hammer rebound value tests are done on core sample. 2
Research Proposal 2.
Problem statement
Large scale constructions such as bridges, multi storied buildings are built to last for generations, so quality of the used aggregates is a major concern. As a result quality controlling of aggregates is broadly used in the industry. It is evident that we have to bear up some expenses for quality controlling. The purpose of this study is to develop a method to reduce the cost associated with quality controlling of aggregate. What are the testing methods used for the quality checking of aggregates? What are the most important tests in quality checking of aggregate? What is the cost for each test? How can cost of quality controlling be reduced without compromising the quality of the product? 3.
Problem justification
According to the standard of ISO 9001, 2008- Quality management system, quality of every input should be controlled by the producer to obtain the ISO certification. To get higher grade than C3 from ICTAD registration, contractors must obtain the ISO 9001, 2008 certificate. This criteria force contactors to check the quality of aggregates which is one of the main input of their production. This situation makes the aggregate industry to invest their money for the quality checking purpose and therefore quarry owners or the contractors have to bear the cost of this process.
Normally tests such as Loss Angeles abrasion value test (LAAV), Aggregate Impact Value test (AIV) are utilized for predicting the quality in aggregate quality controlling. From them LAAV test is much expensive than other rock strength tests. We can reduce the cost of quality controlling if LAAV value can be predicted by using less costly tests such as Schmidt hammer rebound value test, point load index, aggregate impact value and Uniaxial compressive strength test.
Other most important parameter for quality checking of aggregate is AIV value. The procedure of AIV is little bit sophisticated than other tests and time consuming. If we can predict the AIV results using less sophisticated and less time consuming method it will great opportunity to the industry to reduce the cost by saving time
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Research Proposal 4.
Significance of the project
This research is focused to check the correlations between expensive tests and less expensive tests in order to reduce the cost associated with quality controlling of the aggregate industry. Since aggregate is the key element in any kind of constructions, construction industry had to bear a significant cost to check the quality of the aggregate. If one can develop a correlation between expensive tests and less expensive tests, which are used to check the quality, the industry can invest their funds in more effective way.
With the regulations of ICTAD registration for the construction companies in Sri Lanka, tendency for quality controlling of aggregate is becoming very high at the moment. This causes the owners of quarries to invest more money and the time for quality checking of their product. If there is a method to predict the results of more expensive test by using results of less expensive results and results of more sophisticated and time consuming tests by using results of simple and less time consuming tests, quarry owners can feel a relief regarding cost as well as the time. 5.
Scope of the project
This research will be carried out to reduce the cost associated with quality controlling of aggregate industry by predicting results of more expensive and time consuming test using the results of less expensive, simple and less time consuming tests. To carry out the experiments, rock samples will collect from the selected quarries form western province since there are several important development activities related to construction field are commenced in the western province.
6.
Objectives
To reduce the cost of quality controlling of aggregates, by finding correlations between more expensive tests and less expensive tests. To find correlation between sophisticated and time consuming tests and simple less time consuming tests to reduce the time consumed for quality check.
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Research Proposal 7.
Literature review. 7.1
Quality controlling of aggregates
Every product has to be considered for quality controlling, since the performance of the product should be up to the standard. Basically we can clarify quality controlling as predicting a product’s performances within predetermined limits for a desired portion of the output. That means the desired portion should fall within the established upper bound and the lower bound. The suitability of aggregates for a construction is determined by assessing the material in terms of its physical and mechanical properties. In most specifications specify the strength of aggregate use for the project (Al-Harthi A, 2001). According to Ugur, S at al (2009) aggregates used must be tough and abrasion resistant to prevent crushing, degradation and disintrigation when stockpiled, fed through and asphalt plant, place with paver, compacted with rollers and subjected to traffic load. Aggregates, which do not have adequate toughness and abrasion resistance, may cause construction and performance problems (Wu, Y et al, 1998). 7.2
Tests used for quality checking of aggregates.
The Loss Angelis Abrasion Value test and the Aggregate impact value tests are the two tests which determine the resistance to the abrasion and fragmentation due to impact and these two tests have considerable utility in checking the quality of the aggregate. (Femlund, J, 2005). Although the Loss Angelis abrasion test is more important, it is time consuming and expensive compared with other tests used in rock mechanics. In comparison, indirect tests such as Schmidt hammer rebound tests and point load test are very easy to perform, required small samples and less sophisticated testing methods. (Kahraman, S and Gunaydin O, 2007). When compare with the unconfined compressive strength test, which is also used to determine the strength of rock, Loss Angelis abrasion value test is time consuming and require more sample ( Kahraman S and Fener, M, 2007)
7.3
Correlations between tests.
Some researchers have investigated the correlations between tests used in aggregate quality controlling. Kahraman S, and Fener, M(2007) obtain a good correlation between Los Angalis abrasion value and unconfined compressive strength for igneous, sedimentary and metamorphic aggregates in Turkey. Cargill and Shaakoor( 1990) established a non-linear inverse relation 5
Research Proposal between compressive strength and Los Angelis abrasion value test for sedimentary and metamorphic rocks. In 2007 Kahraman and Gunaydin obtained a strong correlation between Los Angelis abrasion value test and Schmidt hammer value, and Los Angelis abrasion value test and point load index from the experiments they done on 35 different rock samples.
8.
Conceptual Framework AIV UCS
Correlation
LAAV
Correlation
AIV
Smitch Hammer Rebound Value Point Load Index UCS Smitch Hammer Rebound Value Point Load Index
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Research Proposal 9.
Hypothesis
Ha1
There is a correlation between Los Angelis Abrasion Value and unconfined compressive value for gneiss rock in Sri Lanka
Ho1
There is no correlation between Los Angelis Abrasion Value and unconfined compressive value for gneiss rock in Sri Lanka
Ha2
There is a correlation between Los Angelis Abrasion Value and point load index value for gneiss rock in Sri Lanka
Ho2
There is no correlation between Los Angelis Abrasion Value and point load index value for gneiss rock in Sri Lanka
Ha3
There is a correlation between Los Angelis Abrasion Value and Schmidt Hammer Rebound Value for gneiss rock in Sri Lanka
Ho3
There is no correlation between Los Angelis Abrasion Value and Schmidt Hammer Rebound Value
Ha4
There is a correlation between aggregate impact value and Schmidt Hammer Rebound Value
Ho4
There is no correlation between aggregate impact value and Schmidt Hammer Rebound Value for gneiss rock in Sri Lanka
Ha5
There is a correlation between aggregate impact value and point load index value for gneiss rock in Sri Lanka
Ho5
There is no correlation between aggregate impact value and point load index value for gneiss rock in Sri Lanka
Ha6
There is a correlation between aggregate impact value and unconfined compressive value for gneiss rock in Sri Lanka
Ho6
There is no correlation between aggregate impact value and unconfined compressive value for gneiss rock in Sri Lanka
Ha7
There is a correlation between Los Angelis Abrasion Value and aggregate impact value for gneiss rock in Sri Lanka
Ho7
There is no correlation between Los Angelis Abrasion Value and aggregate impact value for gneiss rock in Sri Lanka
H1
H2
H3
H4
H5
H6
H7
7
Research Proposal 10.
Research Methodology
Before commencing this research all the theoretical background related to the research topic will be defined. After that hypothesis are created. Experiments and statistical analysis will be made using the list of hypothesis as a base. With the results of the analysis conclusion will be made. Therefore to carry out this research, it is appropriate to use deductive research approach. 11.
Research Strategy
Since the research is focused to find correlations between testing methods the research strategy to be used for this is experimental. 12.
Collection of data
Tests will be conducted on rock samples collected from selected quarries in western province of Sri Lanka
12.1
Selecting Quarry sites
In selecting quarry sites to take rock samples for this study, quarries situates within Western provinces will only be considered with considering the time and the expenses related to sample collection. According to the GSMB there are more than 25nos of A grade quarries in western province. From them 5 quarries will be selected to collect samples to perform tests.
12.2
Collecting rock samples
Rock samples will collect (boulders) randomly from the quarry faces or from the production of blasts
12.3 Preparation of samples for testing. Rock samples will core perpendicular to bedding or foliation plane, in the laboratory by using a NX type (54mm) drill bit in a Hilty core cutting machine (Switzerland HILTI, 2004) to prepare them for unconfined compressive strength, point load index test and Smitdth hammer rebound value test.
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Research Proposal Aggregate samples will prepare from bulk rock samples, after they core for UCS, PLI and SHR. Primary size reduction will obtain by a hammer and further size reduction will achieve by using a proto type jaw crusher (England, Denver, 2004 ) in the laboratory. Once the rock break to approximate sizes, they will sieve to obtain accurate size ranges according to the test standards (ASTM(C 131), ASTM (C125) and (D5731)).
12.4 Performing tests All tests will perform according to ASTM standards. 12.5
Data analysis
All the results of test will analyze statistically by using least square regression method with the use of matlab software
12.6
Validation of the results
Results of tests done earlier for rock samples collected from quarries located in Western province will gather from reputed geotechnical companies in Sri Lanka as secondary data. Using these data, correlations gain by the research will be verified .
13. Conclusion As stated in the problem statement construction companies and quarry owners in Sri Lanka have to bear a significant cost on quality controlling of aggregates. If we can predict the results of more expensive and time consuming test by using results of less expensive and less time consuming tests, we can reduce the cost involved with the quality controlling without compromising the quality of aggregates. From the literature review it appears that some researchers found correlations between these tests which can be applied only for their countries. In Sri Lankan context no published data was found on this topic and by doing this research we can give a solution for construction industry to reduce its cost related to quality controlling of aggregates.
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Research Proposal 14. References Al-Harthi AA, A field index to determine the strength characteristics of crushed aggregates, Bull Eng Geo Env,2001:60.193-200 ASTM standard C125, 1995, “Aggregate Impact Value test”, ASTM International, West Conshohocken ASTM standard C131, (1995), Los Angeles Abrasion value test, ASTM International, West Conshohocken ASTM standard D2938, (1995)-Unconfined compressive strength of intact rock core specimens, ASTM International, West Conshohocken ASTM standard D5731, (1995), Determination of point load strength index of rock ASTM International, West Conshohocken ASTM standard D5873, (1995), Determination of rock hardness by rebound hammers method, ASTM International, West Conshohocken. Kahraman S and Gunaydin O, Emperical methods to predict the abrasion resistance of rock aggregates, (2007) Snedecor GW, (1989), Statistical methods, Ames, Iowa, Iowa State University. p.503 Sri Lanka Ports Authority. (July 2006). Sri Lanka: Proposed Colombo Port South Harbor Development Project. Available: http://www.adb.org/documents/environment/sri/39431sriseia.pdf. Last accessed 20th December 2012. S.Ugur and Demirdag H, Effedct of rock properties on los Angeles abrasion and impact test characteristic of the aggregate, 2009,Suleyman University, Turkey Wu,Y, Parker F and Kandhal K, Aggregate toughness/abrasion resistance and durability/soundness test related to asphalt concrete ,Auburn University, 1998, NCAT report No:98-4
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