Building Beach Homes - Different Types and Components of Foundations

In examining the different types of foundations thecarry their loads through weak strata down to a
first that we review is the raft foundations. A raftbearing in firm strata below.
foundation is basically a large concrete slab designedShort-Bored piles are relatively short length piles used
to cover the whole area or part of the site. It isin firm shrinkable clay as a means of pitching the
used on soft or weak natural soil or made-up groundfoundation below the zone of moisture movement.
(fill) or ground liable to subsidence as in mining areas,They are usually large in diameter (three hundred
or where column are closely spaced that their basesmillimeters) relative to their short lengths so no steel
may be to close, touch or overlap, for example,reinforcement is normally necessary and they are
where seventy-five per cent of the site may bestiff.
covered. Though a raft foundation is used for weakFactors which determine Width and Depth of
soil it cannot be used for Jamaica beach homes thatFoundationsThe width and depth of foundation varies
require a much more sturdy foundation.with the:o Character of the subsoilo Weight of the
Types of Raftwall and the load which it carrieso Nature and
Solid raft consists of a solid two-way reinforcedstrength of the materials to be used in the design of
concrete slab. Light rafts are used for small loadthe foundations; ando Likely behavior under load of
bearing type buildings or light framed structures withthe soils on which the foundation rest
low bearing pressures. For heavier and larger buildingConcrete in FoundationsThe strength of concrete is
thicker and deeper raft are used.influenced by a number of factors:
Beam and slab raft consist of slab bearing directly on1. Proportion and type of cement
the ground with bean ribs project above it. It is2. Type, proportions, grading and quality of
useful where loads or rigidity needs require a slabaggregates
thicker than three hundred millimeters. This was3. Water content
experimented on for some beachfront property for4. Method of accuracy of batching, mixing,
sale in Jamaica, but the concept was quicklytransporting, placing, compacting and curing concrete.
abandoned.The majority of concrete foundations contain
Cellular Raft consists of top and bottom slabs (rafts)ordinary cement, although this may be varied special
with edge and intermediate beams in both directionscircumstances. The customary standard mix is 1:2:4.
forming hollow cells. This is useful where raft stressesFoundation Selection Factorso Soil conditionso Type
are high and deep beams (nine hundred millimeters)of structureo Structural load economics of foundation
are necessary to provide the greater rigidity required.typeso Time available for constructiono Life of
Sometimes the depth may be full basement storeybuildingo Future use of building
or storeys using reinforced concrete cross-walls,Settlement
monolithic, with floors and rafts.Settlement is the vertical downward movement of a
Pile FoundationsPile foundations are those whichfoundation on a compressible soil.
transmit loads to deeper levels by means of longCauses of settlement
column bedded in the soil They are suitable on soils1. Consolidation of soil particles
of low bearing capacity, where the water table level2. A reduction in the moisture content of certain soils
is high, where there is the presence of shrinkablewhich shrinks on drying out
clays or other materials near the surface which is3. The general movement of the earth due to
liable to movement. This is what is used for mostvarious causes
beachfront properties for sale in Jamaica.4. Overloading the soil
Types of pilesFriction piles transmit their load to theThe foundation is the most fundamental aspect of
surrounding soil by means of friction between the pileJamaica beach homes as no matter how good a
surfaces and the soil, that is, the piles are supporteddesign is, it will not hold up if the foundation is weak.
by friction between soil and pile. End bearing piles