It is evident that the over-exploitation of natural
resources is currently a major issue with the construction industry. It is
essential for the researchers to find new alternatives which are cheap,
sustainable, environmentally friendly and consist of satisfactory structural
properties where they could convert the non-bio degradable waste into quality
building materials. This idea brought the concept of EPS (Expanded Poly
Styrene) lightweight load-bearing panels. EPS is a material generally used for
packaging or insulation which is non-biodegradable and hence if released into
the nature after its use, it may not decay through natural means (P.L.N.
Fernando, M.T.R. Jayasinghe, & C. Jayasinghe, 2017) .The main advantage
of this EPS panels is the reduction of dead load to the foundation level. As a
result, a cost-effective foundation system can be established for different
This research mainly focusses on the different foundation
systems of apartment building and their suitability to the soil type of
Srilanka. This addresses how the constructability aspect of cost and time have
been reduced in the foundation by means of using lightweight panels as
load-bearing walls in a three-storey apartment building.
EPS panels for load bearing
The applicability of EPS panels for the non-structural
purpose is very common nowadays. Many construction companies prefer the EPS
panels as partition walls since it is cost effective and beneficial to
environment. Mainly the load due to the superstructure will be less and cost
for the foundation will be reduced.
Now, researchers have thought of using the EPS panels for
the load bearing and hence it enhances further effectiveness in the cost
minimization of the construction. Further, the reduction in dead load of the
structure brings a new way for cost effective foundation systems.
3. Foundation properties and soil types
The engineering properties and the behaviour of soil are
important for the foundation design. The foundation of a structure is defined
as that part of the structure direct contact with the ground and which
transmits the load of the structure to the ground (Tomlinson,
The selection of suitable foundation systems for multi-storeyed
buildings are governed by several factors like; building loads, wind and
earthquake effects, ground profile and water table
conditions, chemically aggressive ground conditions, allowable bearing pressure
of soils at different depths, provision of basement storeys, proximity to
adjoining buildings and other project specific requirements (V.
Thiruvengadam, J. C. Wason, & K. I. Praseeda, 2004). The apartment
building of three storey with light weight load bearing panels will be less in
dead load and hence shallow foundation is satisfactory. Other conditions such
as the ground profile, water table conditions, allowable bearing pressure of
soils at different depths will also contribute to the selection of the type of
Table 1: soil parameters
Medium dense sand
(Salam & El-kady, 2017).
Table 1 shows typical
soil parameters for the geotechnical analysis of the soil.
4. Shallow foundation systems
A preliminary study has to be done on choosing the
foundation. The nature of the super-structure, the loads to be transmitted to
the foundation, subsoil profile should be considered in the preliminary study (V.N.S.Murthy,
Various equations have been established for calculating
the ultimate bearing capacity of shallow foundations. The most comprehensive
ones, which take into account the shape and the depth of the foundation and the
ground surface have been derived by Brinch Hansen and by Meyerhof. Both use the
same basic equation,
= density of soil below
B= width of foundation
c= undrained cohesion of soil
= effective pressure of overburden soil
= ground surface inclination factors
3.1 Foundation on cohesion less soil (sand)
The allowable bearing pressures of spread foundations on
cohesion less soils, i.e. gravels, sands and other granular materials, are
governed by considerations of the tolerable settlements of the structures (Tomlinson,
The excavation below the water table will involve unwanted cost and cause
considerable trouble with slumping of the sides and instability of the base of
the excavation. If boreholes or in situ test records shows a marked increase in
density of sand with increasing depth below ground level, it may be tempting to
take the foundation deeper than the normal in order to take advantage of the
much higher allowable bearing pressures (Tomlinson, 1991). If satisfactory
bearing conditions cannot be obtained above the water table, it is often more
economical to pile the foundations than to excavate for spread foundations
below ground water level. The cost
analysis for different conditions is advisable in such situations.
3.2 Foundations on cohesive soils (stiff clay)
Normally the construction of an apartment building is not
a slow process and hence the load comes on to the foundation is relatively quickly.
Most clay soils are saturated and behave as if they are purely cohesive,
provided that no water is expelled from the soil as the load is applied.
3.3 Applicability of computerized methods to
foundation analysis and design
The use of computerized methods for foundation
engineering is very essential since soil have stiffness properties which are
non-linear, heterogeneous and inelastic. The various soil profile with layers
of different soils and their feasibility for shallow foundation can be analysed
with numerous geotechnical software. The software denoting more than computing
a manual method to achieve improved speed of calculation and reliability of the
arithmetic (Tomlinson, 1991).
The finite difference element method and finite element
method could be used for the design calculation of the allowable bearing
capacity and the settlement.
3.4 Structural design criteria of the foundation
Superstructure loads are transferred to the underlying
soil strata through a suitably designed foundation. Therefore, the foundation
of a structure is considered the most crucial structural element in a building (Fathi
Abdrabbo, Zaki I. Mahmoud, & Mariana Ebrahim, 2016).
The apartment building of three story with load bearing
EPS panels will transfer its load to the foundation through the wall and hence
a continuous strip footing is expected.
The allowable bearing pressure for footing design is
obtained from the worst case of bearing capacity and settlement. Theory of
Elasticity analysis and observations indicate that the stress distribution
beneath symmetrically loaded footings are not uniform (Bowles, 1996). The actual stress
distribution depends on both footing rigidity and base soil. For footings on
loose sand the grains near the edge tend to displace laterally, whereas the
interior soil is relatively confined (Bowles, 1996).
The main target of the work presented here is to review
and get the over view about the foundation systems which is applicable for the
apartment building with load bearing EPS panels. The reviewed literature above
elaborates the importance of the cost-effective foundations systems by means of
structurally and geo technically. The appropriate foundation design will reduce
the foundation cost and hence light weight load bearing EPS panels for
apartment building will be more suitable
for construction industry as an
alternative which is environmentally friendly.
I wish to great
fully acknowledge to Prof. M.T.R. Jayasinghe who guided me and gave a brief out
about the EPS panels, Eng. M.B.J.N. Fernando, the managing director of Ekala
pre-stressed concrete industries for providing materials for the construction
of the house and my colleagues for their support in site visits.
Bowles, J. E. (1996). FOUNDATION ANALYSIS AND DESIGN.
Singapore: The McGraw-Hill Companies, Inc.
Fathi Abdrabbo, Zaki I. Mahmoud, & Mariana Ebrahim.
(2016). Structural design of isolated column footings. Alexandria
Engineering Journal (2016) 55, 2665–2678.
P.L.N. Fernando, M.T.R. Jayasinghe, & C. Jayasinghe.
(2017). Structural feasibility of Expanded Polystyrene (EPS) based
lightweight. Construction and Building Materials 139 (2017), 45-51.
Salam, S. A., & El-kady, M. S. (2017). Foundations for
low cost buildings. journal of Computational Design and Engineering-4,
Tomlinson, M. J. (1991). Foundation Design and
Construction. London: Longman Singapore Publishers Pte Ltd.
V. Thiruvengadam, J. C. Wason, & K. I. Praseeda.
(2004). COST MODELING OF FOUNDATIONS OF REINFORCED CONCRETE BUILDINGS. 13th
World Conference on Earthquake Engineering. Canada.
V.N.S.Murthy. (2001). Geotechnical Engineering
Principles and Practices of Soil Mechanics and Foundation Engineering.
Bangalore: Marcel Dekker, Inc.
Abstract: The selection of the appropriate foundation systems
for apartment buildings with lightweight load bearing panels are governed by
several factors like; building loads, wind and earthquake effects, ground
profile and water table conditions, chemically aggressive ground conditions,
allowable bearing pressure of soils at different depths, proximity to adjoining
buildings and other project specific requirements. The EPS light weight load
bearing panels have considerably reduced the building load at the foundation
level and pay the way for cost effective foundation systems. Also, reuse of EPS
is beneficial in terms of environmental protection. This review mainly investigates
the different foundation systems and their suitability with different soil
types for the design of apartment building with EPS load bearing panels.
Foundation system; Cost; Soil; Structural design