Setting out building work
Before a decision about the final siting of a building can be made, a number of factors have to
be taken into account. Consideration must be given to local authority and planning
regulations, to functional requirements, orientati
Dairy Cattle show a reduced feed-intake under heat stress resulting in lowered milk production and
reduced growth. Reproduction is also adversely affected. There are, however, important differences
between breeds. European cattle (Bos Taurus) produce well
Improved livestock management Herding has been the traditional method of controlling livestock
movements during grazing. Fencing was only done to exclude the animals from certain areas such as
homesteads and cultivated fields and to safeguard them at nigh
ABE 462: AGRICULTURAL STRUCTURES Prerequisite : ABE 451: BUILDING MATERIALS Contact Hours:
42
Course Purpose The purpose of this course is to provide students with skills required for design of
various farm structures
Expected Learning Outcomes of the cou
humid volume. Example A total of 70 dairy cows at 500kg body mass are housed in a mechanically
ventilated building. The moisture production is 731 g/h-animal. What must be the ventilation rate in
ABE 462: AGRICULTURAL STRUCTURES
J. K. TARAGON (2016) Page
The U value for a sheet metal roof is 3.03 W/(m.K); for a thatch roof, 0.26W/(m.K); for an adobe
wall, 2.5W/(m.K); concrete block wall, 2.9W/(m.K), single glass, 6W/(m.K) and timber door is
2.4W/ (m. K).
We know that, Q = A x U x T
a) Thatched Roof Item A
Equation 1 Where U is the overall unit area thermal conductance of component (W/m2K), A is the
area of structural component (m2), c is the path of heat transfer, which may be a wall or roof
component, P is the building perimeter (m), F is an experimentall
The best propeller fans have a close-fitting curved inlet shroud or inlet ring which improves the
efficiency of the fan. Propeller fans are most suited to moving large volumes of air at pressures in the
range of 30 to 50Pa (3 to 5mm of water) and they are
The ventilation rate is usually expressed as the cubic metres per second of airflow per square metre
of floor area. To obtain a reasonable heat rise of less than 4C in a glass-clad house, the airflow rate
in the tropics should be 0.04 to 0.05m/s per m of
Although the immediate objective of these plans may be the inclusion of a new building in an
existing farmstead, provision should be made for future expansion and replacement of buildings. In
this way a poorly laid out farmstead can be improved over the l
Assuming a uniform mixture:
Equation 10
When the volume and temperature of the mixture are equal the following is true:
Equation 11
Thus, if the total pressure and water vapour weight is known the partial pressures may be calculated.
Specific humidity (H)
to reduce the effectiveness of insulation or cause deterioration in wood or metal. In cold climates,
building walls should be designed with vapour barriers on the warm side of the wall in order to
reduce moisture permeation. In all climates, but especiall
Figure 1.7 Architectural symbols.
Figure 1.8 Symbols for installations in buildings.
Figure 1.9 Symbols for materials.
Figure 1.10 Simple cardboard hanger for drawings
Site Plan
Scale 1:1000, 1:500, or 1:200
The location of the building in relation to its
Equipment needed in the workshop will depend on the type and extent of work to be done.
Generally this means those tools required to perform day-to-day maintenance on machines and to
carry out general repair work and small construction jobs required on fa
COURSE OUTLINE Week Topics and contents Remarks
1&2
Functional Planning
CAT 1
Rural planning Economic planning Building planning Farmstead planning Fire protection
3, 4 & 5
Cimate and Environmental Control Heat transfer and thermal resistance Moisture tra
temperature in building (K), is density of air in building ( kg/m), S is specific heat of air (1005J/
kgC), V is ventilation rate (m/s) and W is heat loss through building shell (W/C)
Natural ventilating systems may be non-adjustable, manually adjustable,
Drawing technique
Drawings are essential for planning buildings, for completing the engineering design, for
estimating the quantities of materials and relative costs and finally to communicate to the
builder all of the information that the designer has de
FORMS OF PLANNING Regional planning What is a region? Essentially, it is a tract of land which, by
virtue of geographical, political, economic, administrative, historical and other factors, or a
combination of these, is distinguishable as a unit, a separa
Air-water vapour mixture processes Conditioning of air-water vapour mixtures involves heating,
cooling, humidifying dehumidifying or some combination of these factors.
Sensible heat is the heat added to air without changing its specific humidity. Applicat
4 refill bucket from graduated cylinder, noting the amount of water needed to refill the
bucket.
5 Density = weight/volume = kg/m
6 Place species in appropriate group using appropriate density column for a green or
dry sample. See Table 3.2, column 3 or
Slump Test
The slump test gives an approximate indication of the workability of the wet concrete mix.
Fill a conically shaped bucket with the wet concrete mix and compact it thoroughly. Turn the
bucket upside down on the mixing platform. Lift the bucket,
Mixing
Mechanical mixing is the best way of mixing concrete. Batch mixers with a tilting drum for
use on building sites are available in sizes from 85 to 400 litres. Power for the drum rotation
is supplied by a petrol engine or an electric motor whereas t
Sand 311 kg - 12 kg = 299 kg
Stones 592 kg- 9 kg= 583 kg
Total amount of dry aggregate = 299 kg + 583 kg = 882 kg
Water = 62 kg + 12 kg + 9 kg = 83 kg
5 Calculate water- cement ratio and cement - aggregate ratio.
Water - cement ratio = (83 kg water) / 100
Often, however, the land has a considerable slope and must be leveled before construction
can begin. In some cases the soil must be removed from the site, but frequently what is
removed from the building site can be use for fill in an adjacent area. Estim
b = least dimension of cross section, r = radius of gyration
1 In this case the end conditions for buckling about the x-x axis are not the same as about the
y-y axis. Therefore both directions must be designed for buckling. (Where the end conditions
are t
In some literature the required grade of concrete is noted by the proportions of cement - sand
- stone, so called nominal mixes rather than the compressive strength. Therefore some
common nominal mixes have been included in Table 3.12. Note, however, that
Number of bags of cement required = 320/37 = 8.6 bags, i.e., 9 bags have to be bought.
Weight of sand required = 0.95m x 1.45 tonnes/ m = 1.4 tonnes
Weight of stone required = 1.89m x 1.60 tonnes/m = 3.1 tonnes
Maximum size of stones = 70mm x 1/4 = 17mm
E
Find a suitable beam depth assuming 100mm breaths:
From table 4.3 the section modulus for a rectangular shape isZ=1/6 x bd2
Choose a 100 by 225mm timber. The timber required is a little less than that assumed. No
recalculations are required unless it is e