The Term paper presents the comparison of different approaches of mix designs to be feasible if used in Libya and its local variables.

1. UNIVERSITY OF TRIPOLI
FACULTY OF ENGINEERING
DEPARTMENT OF GRADUATE STUDIES
Topic:
Feasibility Study for
different mix designs in
Libya
A Term Paper Submitted
In Partial Fulfillment of Clearing the CE-602 Module
Prepared By : Muhammad Abdul Azeem Baig
Supervised By: Prof. Hakim S. Abdelgader
June, 2018

2. 2
Contents
1. Abstract: ......................................................................................................3
2. Introduction:................................................................................................3
3. General problems related with concreting in Libya: ....................................3
3.1 Method of concreting.............................................................................3
4. Methodology:..............................................................................................4
5. The ACI method:..........................................................................................4
6. The British method (DOE) : ..........................................................................5
7. The three equation method :.......................................................................6
8. The double coating method:......................................................................P6
9. Conclusion & Recommendations:................................................................7
10. Acknowledgement.......................................................................................7
11. References...................................................................................................8

3. 3
Feasibility study for different mix designs in Libya
1. Abstract:
It must be noted that the author of this paper intends to present a comparison of various mix
designs, and not to get in detail steps & methodology of mentioned mix designs. The values
of the physical and geotechnical parameters of component materials form the basis of the
concrete mix design considerations [1].
Finally the purpose of this paper is to give an abstract idea to the readers whom are
new in Libya or have little or no knowledge on how things go around in different sectors of
construction in Libya.
2. Introduction:
During the past few decades the concrete has come up as the major building material, also its
been widely studied and developed in different fields related to construction all over the
world. Due to the ease of making and success related to many factors, many mix designs
were produced, where some of them with very unique approach while others were a derived
from other mix design procedures.
Also; in Libya, the approach used in concreting other than at research centers,
universities, and concrete batch plants , is very un-professional, and hence a need for
selection of a mix design method which could be used at site, while using local materials ,
with least labor expertise & tests while producing maximum quality concrete was required.
3. General problems related with concreting in Libya:
This topic is of shear importance and has been least talked about in the past, the building
industry in Libya can be divided mainly into two parts:
(a) Low to mid-level construction ( non-governmental construction)
(b) High level ( Governmental Construction )
Now, even by a simplest review and questionnaire it was known that the first type of
construction is the most extensively been used in Libya, and this type although
contributing to nearly most of construction done in libya today is done without
specification kept in mind.
Before we go in detail, we can further divide the method of concreting into following
types:
3.1 Method of concreting
a) Hand mixing: used for very low-level works and hence is out of scope of this
paper.
b) On-site and portable concrete mixers : The following are the main problems
associated with this type :
i. No mix design calculations are performed

4. 4
ii. Usually no admixtures are added
iii. Poor mixing time
iv. labors with Little or no knowledge
v. no site test are performed
vi. no vibration is done
vii. Poor proportioning of material on lump sum basis, hence
increasing the inconsistency along different batches performed
at site.
c) Concrete placing by pump and mixed within truck or at batch plant:
i. Unknown quality of cement and mix
ii. Over mixing due to long distances and unsynchronized mixing speed.
iii. No strict regulations applied on companies offering such services.
iv. Although a bit more costly but still the best available option within
Libya .
4. Methodology:
As the title of the paper suggests, the following are considered as basic parameters for
feasibility study:
(a) Location analysis
(b) Cost analysis
(c) Preparation, placing and curing analysis
The following mix designs will be studied, Provided the aforementioned analysis criteria:
1) The ACI method
2) The British method (DOE)
3) The three equation method ( bolomya method)
4) The double coating method
5. The ACI method:
The ACI method is one of the most used method all over the world, and its design is
basically dependent on tests done in laboratory & observation on samples.
(a) The location: the ACI method use in Libya is practically impossible
due to the minimum fine aggregate size specified by AASHTO is not
physically feasible in Libya as the fine aggregate is very fine in its
naturally available form, although there are techniques to make the mix
design workable by adding specified sized aggregate to satisfy the
condition.
(b) Cost analysis : the following are basic set backs of this method in
regard to cost:
i. Iterative Testing of specimen is required during the design,
which is a very expensive thing and rarely available in Libya

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ii. Very highly skilled labors and engineers are required to achieve
the best quality of concrete, while adding it to be expensive
method.
iii. The cement content is very high as compared to other mix
designs.
(c) Preparing , placing and curing:
i. Very highly skilled labor and engineers are required to achieve
the best quality of concrete, which is very hard to find for
normal to low level construction.
ii. The placing of concrete usually does not involve vibrators
iii. No on site test are available for general construction.
6. The British method (DOE) :
This method is one of the oldest method available and is based on Road Note No 4
method. It was made in 1988 , also this method is applicable to concrete for most purposes,
including roads.
This method of mix design provides a compilation of tables and charts that could help
a designer to extract information regarding the design being embarked upon.
Water/cement ratio is selected for a given range of compressive strengths and slumps.
The cement content is in turn selected for the type of aggregate and grading available.
The charts give clue on the ratio of coarse to fine aggregates [1].
With that said the following points are viewed as apparent consequences of usage of
above mentioned method:
(a) The location : the british methods mainly presents a better approach
then ACI , in regard to aggregate specifications , as it mainly classifies
aggregate as crushed and uncrushed to be used , and then other
following mix design procedures can be done. Therefore, generally
speaking this approach is better applicable to the kind of aggregate
abundantly found and used in Libya.
(b) Cost analysis : the following are basic set backs of this method in
regard to cost:
i. Iterative Testing of specimen is required during the design,
which is a very expensive thing and rarely available in most
constructions done in Libya.
ii. Very highly skilled technician and engineers are required to
proceed with tedious mix design procedure in order to achieve
the best quality of concrete & thus making it to be an expensive
method.
iii. The cement content is relatively high as compared to other mix
designs.
(c) Preparing , placing and curing:

6. 6
i. Very highly skilled labor and engineers are required to achieve
the best quality of concrete, which is very hard to find for
normal to low level construction.
ii. The placing of concrete usually does not involve vibrators
iii. No on site test are available for general construction.
7. The three equation method :
This method makes a direct relation of compressive strength of concrete with type of
cement and aggregate used, in addition to this , the water content is a function of
aggregate grading.
This method is considered as one of the most important concrete mix design
methods due to the following advantages [3]:
 Introducing of the effect of water demand by cement in the design process
[3]
 Introducing of the effect of water demand by fine and coarse aggregate as
well as the grading in the design.[3]
With that said the following points are viewed as apparent consequences of usage of above
mentioned method:
(a) The location: the geotechnical significance of this method can be
defined on its basis of recognition of aggregate as round or angular,
which may be appraised due its adaptation to simplicity & availability.
(b) Cost analysis : the following are basic setbacks of this method in
regard to cost:
i. Iterative Testing of specimen is required during the design,
which is a very expensive thing and rarely available in Libya
ii. Normal skilled technician and engineers can proceed with
relatively simpler mix design procedure in order to achieve the
best quality of concrete & thus making it to be an adequate
method.
8. The double coating method:
The approach used in this method is highly appreciable in terms of accurate proportioning
at site, with least trained labor capable of generating quite highly accurate concrete mix
required as designed. The philosophy of this mix design method is based mainly on
calculating the weights of the main ingredients of concrete that occupies a volume of one liter
of water taking in consideration the following two assumptions: [4]
1-The Spaces between fine aggregate particles assumed as Rf. This distance (Rf)
actually represents the diameter between sand particles which will be filled by cement
paste, [4]

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2- The Spaces between coarse aggregate particles assumed as Rg. This distance (Rg)
actually represents the diameter between coarse aggregate particles which will be
filled by cement mortar (mixture of cement and sand) [4]
With that said the following points are viewed as apparent consequences of usage of
above mentioned method:
(a) The location :the geotechnical significance of this method can be
defined as it recognizes the aggregate as round or angular , which may
be appraised due its simplicity of recognition (similar to three eq
method ).
(b) Cost analysis : the following are basic setbacks of this method in
regard to cost:
I. Iterative Testing of specimen is required during the design,
which is a very expensive thing and rarely available in Libya
II. Normal skilled technician and engineers can proceed with
relatively simpler mix design procedure in order to achieve the
best quality of concrete & thus making it to be an adequate
method
9. Conclusion & Recommendations:
The ACI and BS methods are the most commonly used. Both of these methods depend on
graphs and standard tables derived from previous research experience and actual concrete
production as well as studies of the properties of the materials used (Neville 1987).
Also , It can be concluded that the bolomeya method due to its simplicity and double coating
method due its high practicability , are the most suitable mix designs to be used locally while
ensuring no limitations to geotechnical implications for materials to be used in the mix.
It is, therefore, recommended that contractors of civil works appreciate and also take
advantage of the integrity and quintessence of concrete mix designs. Further work is also
required in order to investigate the integrity of the other existing mix design methods and to
recommend a particular mix design for a particular project category & location.
It must be added that concrete testing and placing is not a characteristic criteria for mix
designs comparative study .
10.Acknowledgement
This research work was done at University of Tripoli, 2017-2018. Further, the author is
immensely indebted to the supervisor Prof. Hakim S Abdelgader , Department of Civil
Engineering, and the colleagues for their timely help throughout the span of the research
work.

8. 8
11.References
[1] INFLUENCE OF MIX DESIGN METHODS ON THE COMPRESSIVE
SRENGTH OF CONCRETE by Aginam C. H., Umenwaliri S. N. and Nwakire, C.
ARPN Journal of Engineering and Applied Sciences
[2] Bolomeya model for normal concrete mix design : Hakim S. Abdelgader and Ali S.
El- Baden, Civil Engineering Department University of Tripoli, Tripoli, Libya James
M. Shilstone, Shilstone Companies, Plano, TX, USA
[3] CONCRETE MIX PROPORTIONING USING THREE EQUATIONS METHOD
(LABORATORY STUDY) : H S Abdelgader1 , R E Suleiman2 , A S El-Baden1 , A
H Fahema1 , N Angelescu3
[4] Concrete Mix Design Using Double Coating Method : H. S. Abdelgader1, A. F.
Saud1, A. M. Othman1, A. H. Fahema1 and A. S. El-Baden1