Seashell Pervious Concrete: A Green Substitute for Conventional Pavements

Griffith School of Engineering and Built Environment
7001ENG – Research Methods for Engineers
Trimester 01, 2019
Final Assignment – Research Proposal
DECLARATION: I declare that this research proposal contains no material which has been submitted for assessment in any
other subject at Griffith University or elsewhere. To the best of my knowledge and belief, this research proposal contains no mate -
rial that has been previously published by any other person, except where due acknowledgement has been made.
Student name: Student number:
Program in which student is enrolled:
SEASHELLS PERVIOUS CONCRETE
PROJECT SUMMARY
Concrete is a mixture of a paste comprising of water and Portland cement and aggregates. The concrete constituents
are usually mixed to obtain required chemical and mechanical properties. This article will look at the study and devel-
opment of seashell pervious concrete. Seashell pervious concrete can be used as a green substitute to conventional
pavements with huge spaces and low fine aggregate content. Pervious concrete accommodates water infiltration via
the pavements hence lowering runoff and the need for managing storm water systems.
A substantial quantity of seashells-by products produced are regarded as wastes. This paper focuses on how seashell-
by products can be recycled to obtain products that are environmentally friendly. Hence, the research aims at using re-
cycled oyster shells as pervious concrete’s aggregates. The qualitative and quantitative methodology will be used in
describing possible alternative for coarse aggregates in the design mixture of pervious concretes. Tests will be con -
ducted to determine the strengths, space content and permeability of seashell pervious concrete. Thereafter, compared
to the natural aggregate pervious concrete mixture as the control experiment. The samples’ permeability and strength
will be inspected to control the pervious concrete mixture, thereby, producing a precise balance of pervious concrete
mixture.
KEYWORDS: permeability, seashell-by products (SBP), mechanical strength, pervious concrete, environment.
1. INTRODUCTION
The student Encarta defines concrete as a mix of cement, sand, water and aggregates in specified proportions which
hardens over varying duration of time in to a strong consistent stony. In this context, aggregate means rock particles
measuring over 5mm. Concrete may be defined as composite materials with binding substance used to embed parti -
cles. Concrete has also been defined by other scholars as a mixture of a paste comprised of water and Portland cement
and aggregates. The aggregates refer to crushed stones or gravels and sand. The concrete constituent materials in -
clude:
 Water and cement = cement paste
 Sand and cement paste = mortar
 Stones and mortar = concrete
Admixtures can also be added to control the mixture’s setting properties (Pimienta, 2018).
7001ENG – Research Methods for Engineers, Trimester 01, 2019 Page 1

1.1 Background
Pervious concrete refers to composite materials comprised of coarse aggregates, water, Portland cement and no or
minimal fine aggregates that accommodates the through passage of water. Generally, there is no slump with very min-
imal cement to water ratios and minimal cement to aggregate ratios. This is sufficient to provide the aggregate adhe -
sion but not sufficient for porosity lose. These reduced ratios partially cause the pervious concrete to become both
sustainable and lightweight product because less materials are required to manufacture it (Han, Zhang, & Ou,
2017).
Figure 1. above shows permeable pervious concrete (Nazarko et al., 2015).
France has a substantial shellfish farming and fishing industries which produces shellfish approximately 45,000 tons
from fishing and shells of about 160,000 tons from breeding shellfish annually in Europe. The activities results in to
many tons of empty shells that are regarded as wastes to be discharged. France has put various efforts in place to recy -
cle the wastes as animal feeds or soil conditioner however, none of this was satisfying in relation to added value recy -
cling and viability. Landfill disposal is the common way of waste management thus increasing effects on the environ-
ment (Scales, 2015).
On the contrary, the utilization and production of concrete as a construction material is increasing constantly this days.
This has led to increased intake of natural aggregates as a huge component of concrete. The approximated world’s
concrete consumption is 6 billion tons annually as we speak (Jahangir, Warid, & Mohamed, 2019). There are
a number of research implemented to find an alternative for natural aggregates used in concrete by slag aggregates, re-
cycled aggregates and today seashells. For the past years, the properties and effects of recycled aggregates added in
concrete have caught the attention of many researchers.
1.2. Benefits of the Topic
One of the benefits of this study is to obtain very minimal environmental effects concerns as possible. Seashells are
the most sustainable aggregates as green concrete. The excess amounts of the commercial shells harvested may be re-
leased back to the ocean for them to be reef reconstructed (Ramnath, Jeykrishnan, Ramakrishnan, Barath,
& Ejoelavendhan, 2018). The remaining shells can be sold to industries manufacturing poultry feeds who are
the highest bidders.
Figure 2. above shows crushed seashells (Ramnath, Jeykrishnan, Ramakrishnan, Barath, &
Ejoelavendhan, 2018).
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Oyster seashells are being used by numerous coastal people as driveway pavements. These shells are normally put on
the ground without mixing any cementitious composite. Enterprising people develop artificial tank fish structures
from crushed shells. Some individuals make further efforts of using the latest tabby formula to redesign the old fash-
ion while retaining the successful use of latest code standards (Caicedo, 2018).
The importance of pervious concrete pavements with seashells are as follows:
 No stagnant water or puddles causing minimal harmful hydroplaning
 Minimal glare leads to improved visibility
 Popcorn-like textures offers tires good grip on the road
 Huge air spaces prevents pumping actions thus lowering the temperature of the tire
 Improved sound insulation leads to reduced road noise.
1.3. Literature Review
Rajczyk, Kurakina, and Knapiński (2018) investigated the SBP used in pervious concrete pavers as coarse aggregate.
Natural aggregates were replaced by adding SBP of 20%, 40% and 60% to the mix. The results of the test revealed
that pervious concrete with lower than 40% SBP had higher strengths with space content and better permeability. This
is almost similar to pervious concrete comprised of natural aggregate only. Mixture designs of 40% or high SBP expe-
rienced huge strength loss and high permeability and space content. Therefore, the maximum SBP percentage to be re-
placed in pervious concrete is 40% of natural coarse aggregates directly replaced.
Nazarko et al. (2015) researched on the usage of pervious concrete, that is, New Era for Rural Road Pavement. This
article outlines preliminary concepts on pervious concrete as an idea that is relatively new for road pavements in rural
areas. It also reflects on the rural areas challenges such as agricultural and low water levels in the ground. Pervious
concrete is the most suitable because it allows water to pass via itself to reduce runoff of storm waters and recharge
water levels in the ground. Hence the uniqueness and effectiveness of pervious concrete is a means to acquiring rapid
environmental demands. The technology allows efficient usage of land by removing the requirement for retention
ponds. Pervious concrete pavements are more favorable in rural oceans in meeting the needs in rural areas which in-
cludes reducing the recharge of ground water and storm water runoffs. A pavement measuring 1m × 1m × 0.15m can
be made using durability features with as low as Rs. 18 per feet2 or Rs 193/m2 .
Bonić, Ćurčić, Trivunić, Davidović, and Vatin (2015) investigated the underground impacts of chemical and porous
pavements -soil moisture properties. A study on the relationship between chemistry and porous pavements-soil mois -
ture to urban vegetation was conducted. The experiment consisted of 25 plots equally allocated amongst controls con-
sisting of subjected soil and no pavement, and four various pavement treatments a mixture of pavement types such as
impervious and porous, and design of pavement profile with or without gravel base. Results showed that pavements
interfered the soil pH from relatively acidic pH of 5.75 to high neutral levels pH of 6.3. There was a substantial im -
pact on pH below porous pavements as well with the inclusion of a gravel base. Amount of soil Mg, Al and Fe re-
duced whereas Na increased under pavements.
According to Ramnath, Jeykrishnan, Ramakrishnan, Barath, and Ejoelavendhan (2018) seashells are hard components
that can create concrete with high quality. Additionally, cement paste is required to get a favorable workability. How-
ever uncrushed seashells should not be used as they can create spaces in the concrete and reduce the compression
strength. Reduced mechanical strength is equivalent to the amount of aggregates substituted by seashells in concrete.
The resultant concrete is less durable due to their highly porous structures. There is reduced workability due to flat
shaped shells and high absorptions.
Reddy, Gopakumar, and Chetri (2019) investigated the recent application of seashells in the fabrication of pervious
concrete, whereby, the technical literature published the properties of the concretes. The article aims at comparing the
pervious concrete’s crucial performance aspects using control pervious concrete containing natural aggregates.
Through the research, the mechanical and physical features of pervious concrete made of seashells highly rely on the
quality of seashell aggregates such as grading, nature and size. The mechanical strength of pervious concrete made of
seashells is very small compared to the control pervious concrete. There was an increase in permeability due to the
seashell concrete being highly porous. The seashells pervious concrete was placed stiff in fresh condition.
According to Głuchowski, Sas, Dzięcioł, Soból, and Szymański (2019) the thin cement paste that holds together the
concrete at contact point gives the pervious concrete its spaces. Average space contents can vary from 20-30% de-
pending on the compaction methods and type of aggregates. Compaction and space techniques also affect the pervious
concrete permeability. There exists a variety of agreed upon drainage rates based on the most suitable place it is in-
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