Design of Residential Buildings in (High-Wind) Coastal Areas - a PDH Online Course for Engineers, Architects and Surveyors

Design of Residential Buildings in (High-Wind) Coastal Areas

Course Outline

This course will completely review the design process required for residential buildings (one to three-story) to withstand hurricanes and other severe natural hazard events. Specific case examples will be evaluated in detail explaining each procedure with example calculations and complete diagrams.

The required calculations to determine every specific design load (force) which could be applied to the structure is not within the scope of this course. The site-specific forces, which have been previously determined, will be used in this course to design a structure that can withstand these forces.

To determine site-specific design loads it is suggested that the design professional should refer to pertinent sections of the IRC 2000, in addition to those sections of the IBC 2000, which may be cited within this course. Additional reference sources should also include one or more of the following sources in high wind zones.

Minimum Design Loads for Buildings and other structures (ASCE 7-98)
American Forest and Paper Association (AF&PA) Wood Frame Construction Manual for One and Two- Family Dwellings (WFCM)
Southern Building Code Congress International Standard for Hurricane Resistant Residential Construction (SSTD 10)

In this course the design method is Allowable Stress Design (ASD), so there are factors of safety (FS) built into the development of the material stresses and the forces at the connections. This design method has been chosen because (ASD) continues to be the predominant design method in light-frame, residential, wood construction.

The design process involves the following steps after determining all of the site-specific design loads (forces):

Determination the building's foundation, structural frame, and envelope
Determination the connections between individual elements
Determination the elevation, placement, and support for utilities
Selecting the appropriate materials

The course concentrates on determining the actual forces at connections and stresses on specific components, which are applied through vertical and horizontal load paths. The entire design process is based on the fundamental premise that anticipated service and natural hazard loads can and must be transferred through the building in a continuous path to the supporting soils.

Any weakness in that continuous path is a potential point of failure of the building, and any failure creates the possibility for large property losses and the potential for loss of life.

This course is based entirely on the Chapter 12 Designing the Building of the FEMA Publication Coastal Construction Manual (FEMA-55). This course includes a multiple-choice quiz at the end, which is designed to enhance the understanding of course materials. You will be quizzed on the subject document in its entirety.

Learning Objective

This course teaches the following specific knowledge and skills:

Design of structures which are capable to withstand the forces from various types of loadings which could be subjected to a one- to three-story residential buildings during hurricanes or other severe natural hazard events.

Dead loads
Live loads
Flood loads
Wind loads
Earthquake (seismic)
Snow loads
Additional loads caused by long-term
Additional loads caused by short-term erosion and localized scour
Calculation of Frictional resistance of soil
Calculation of the net uplift force
Calculation of Overturning moment
Calculation of Sliding Resistance of Foundation Walls and Footings
Calculation of Uplift forces at Connections
Calculation of Ultimate Compression Capacity of a Single Pile
Calculation of Ultimate Tension Capacity of a Single Pile
Calculation Bending Stresses of a Single Pile
Calculation of a Square Footing with Gravity Loads
Calculation of Nail Shear
Calculation of Nail Pull-out force
Effect of various architectural features on structural integrity
Number of stories
Orientation of the building in relation to the water or street (building access and view from the building)
Building shape
Openness of the floor plan
Cathedral ceilings or unusually high ceilings
Placement of building equipment, including mechanical systems, elevators, baths, and kitchens
Use of areas below the first floor
Use of outdoor areas such as decks, gazebos, and pools
Proximity to neighbors

Load Transfer Design Concepts

All design loads create forces in and on the building. The forces are transferred through load paths.
Load paths always end in the soil that supports the structure.
Loads should be applied to the building, beginning at the top.
Loads should be determined for both the vertical and horizontal load paths.
Load transfer creates forces at connections and imparts stresses in the materials.
Connections and materials must be strong enough to handle those forces and stresses.
The load path must be continuous; any break or weakness in the load path "chain" can result in damage or even structural failure.

Prevention of Primary and Secondary Failure Modes

Uplift: Vertical forces caused by wind or buoyancy exceed the weight of the structure and the strength of the soil anchorage. The building fails by being lifted off its foundation or because the foundation pulls out of the soil.
Overturning: The applied moments caused by wind, wave, earthquake, and buoyancy forces exceed the resisting moments of the building's weight and anchorage. The building fails by rotating off its foundation or because the foundation rotates out of the soil.
Sliding or Shearing: Horizontal forces exceed the friction force or strength of the foundation. The building fails by sliding off its foundation, by shear failure of components transferring loads to its foundation, or by the foundation sliding.
Collapse: Collapse is a secondary mode of failure. Structural components fail or become out of plumb or level under uplift, overturning, or sliding. The building then becomes unstable and collapses. Buildings under extremely heavy vertical downward loads, such as snow, can also fail in bending, shear, or compression of primary structural members.

Intended Audience

This course is intended for engineers or architects involved in design or construction of residential structures or other structures located in high-wind areas, or subject to flooding.

Benefit for Attendee

This course was intended to provide valuable design guidance for engineers or architects involved in the design of residential structures (1 to 3 stories). The information will also provide additional guidance for those projects which are located specifically in high-wind or coastal areas. Step-by-step procedures with detailed examples are provided to guide the design professional through every step of the design process.

Course Introduction

This course will review the basic design procedures, which should be followed for the design of residential structures (1 to 3 stories) located specifically in high-wind or coastal areas.

The Building Design process will based on the following steps

Use codes, standards, experience, judgment; state givens and assumptions.
Apply loads to building starting at the top; assume a building type, frame, and materials; assume a design approach (ASD, strength).
Determine forces at connections and stresses on components; apply through vertical and horizontal load paths.
Specify connectors or connection methods to satisfy load conditions; specify materials that meet stress levels.
Note design assumptions on drawings; specify design details on drawings.

The following concepts show how one design step leads to the next:

All design loads create forces in and on the building. The forces are transferred through load paths.
Load paths always end in the soil that supports the structure.
Loads should be applied to the building, beginning at the top.
Loads should be determined for both the vertical and horizontal load paths.
Load transfer creates forces at connections and imparts stresses in the materials.
Connections and materials must be strong enough to handle those forces and stresses.
The load path must be continuous; any break or weakness in the load path "chain" can result in damage or even structural failure.

Course Content

This course is based entirely on the Chapter 12 Designing the Building of the FEMA Publication Coastal Construction Manual (FEMA-55).

The link to the course materials is as follows:

Chapter 12 Designing the Building of the FEMA Publication Coastal Construction Manual (FEMA-55)

Please click on the above underlined hypertext to view, download or print the document for your study. Because of the large file size, we recommend that you first save the file to your computer by right clicking the mouse and choosing "Save Target As ...", and then open the file in Adobe Acrobat Reader.

Related References

The course text references sections located within other chapters of the complete FEMA document. Although this additional information is not required to complete the quiz, a link is provided below with information on how to contact FEMA to obtain a full copy of the document for reference.

http://www.fema.gov/pdf/plan/prevent/nhp/nhp_fema55.pdf

Designers should refer to pertinent sections of the IRC, in addition to those of the IBC cited here.

Additional reference sources should also include one or more of the following sources in high wind zones.

American Forest and Paper Association (AF&PA) Wood Frame Construction Manual for One and Two- Family Dwellings (WFCM)
Southern Building Code Congress International Standard for Hurricane Resistant Residential Construction (SSTD 10)

Minimum Design Loads for Buildings and other structures (ASCE-7)

Quiz

Once you finish studying the above course content, you need to take a quiz to obtain the PDH credits.

DISCLAIMER: The materials contained in the online course are not intended as a representation or warranty on the part of PDH Center or any other person/organization named herein. The materials are for general information only. They are not a substitute for competent professional advice. Application of this information to a specific project should be reviewed by a registered architect and/or professional engineer/surveyor. Anyone making use of the information set forth herein does so at their own risk and assumes any and all resulting liability arising therefrom.