Principles of Wood Structural Design
Understanding
structures is fundamental to the education of the professional
architect. This course provide a structural analysis for entry-level
architecture students. It seeks to simplify the process applied as
fundamentals principles of the practical aspects of structural design.
Introduction
Our
focus in this course is on wood because it's the preferred building
material for residential construction in North America , and Europe. We
will also provide courses about other building material such as
masonry, concrete and steel. However, almost the same principles that
apply to wood, apply as well to all of those other materials.
Wood
is becoming increasingly popular in all type of construction, from
residential to heavy commercial and industrial construction. As with
all materials, the design of wood structures is based on building code
regulations. Durability of wood structures must also be considered and
increasingly environmental considerations are influencing the choice of
structural materials. Compared to masonry, concrete and steel,wood has
environmental advantages.
This tutorial is
an introductory to the wood structural behavior. In this tutorial, we
will estimate the lateral loads on low-rise wood buildings due to wind
and seismic events. The proper determination of loads is one of the
most import steps in the design process. Even if the design of the
structural components is correct, improperly calculated loads will
cause the structure to be incorrectly designed. Therefore, you have to
bear in mind that being an architect is not only a matter of being a
creative artist, you have to understand the science behind buildings.
We will start with a very simple example. We will use a "box" as
structural model. The "box" model is used to show you how buildings are
modeled, and their expected response to wind and seismic induced loads.
Before we get to our example, we need to do a little bit of structural analysis , and define some terms.
1.Structural Behavior
Structural Analysis
The process used to determine the adequacy of a wood is as
follows:Determine the loads,then Calculate the stresses, and finally,
check the allowable stresses against the actual stresses.
Determine the Loads
Determining the amount of weight the structural is going to support,is
the first step in the structural analysis of a structural support.
There are two major categories of loads: dead and live loads. Dead and
Live loads are terms used in mechanical and structural engineering,
especially where analysis of real world objects are required. A 'load'
refers to any type of force exerted on an object, which may be in the
form of a 'weight' like gravitational force, a pressure, or anything
which affects the object in question.
Dead loads:
Typically dead loads are those which do not change over the course of
normal operations of the object,or those who considered to act
permanently. For instance, concrete,roofing, flooring, pipes, interior
partition walls and furniture are considered as some of the permanent
non-structural elements. When calculating the total dead load,
environmental control systems machinery, elevator machinery and all
other construction systems within a building must also be included. The
weight of the structural members themselves normally provides the
largest portion of the dead load of a building.
Usually the magnitude of the dead loads of buildings can be determined
with only a 5% margin of error. Therefore, manufacturers arrange
information regarding properties of building materials systematically
in a table or in columns and rows. Because properties of construction
materials often vary due to the rapidly changing marketplace, it is
always very important to keep up-to-date on the changes. The load due
to these materials is usually expressed as kN/m^3 or lbs/ft^3. However,
for further consideration, they are normally converted to load/area or
load/length.
"To be continued"
Wood Structural Behavior
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