ASCE705W Wind Loading
Description
"ASCE705W" --- ASCE 7-05 CODE WIND ANALYSIS PROGRAM
Program Description:
"ASCE705W" is a spreadsheet program written in MS-Excel for the purpose of wind loading analysis for buildings and structures per the ASCE 7-05 Code. Specifically, wind pressure coefficients and related and required parameters are selected or calculated in order to compute the net design wind pressures.
This program is a workbook consisting of nine (9) worksheets, described as follows:
Worksheet Name
Doc - This documentation sheet
Simplified - Analysis using simplified method for low-rise buildings with h <= 60’
MWFRS (Low-Rise) - Main Wind-Force Resisting System for low-rise buildings with h <= 60’
MWFRS (Any Ht.) - Main Wind-Force Resisting System for buildings of any height
Wall C&C - Analysis of wall Components and Cladding
Roof C&C - Analysis of roof Components and Cladding
Stacks & Tanks - Analysis of cantilevered chimneys, stacks, and vertical tanks
Open Structures (no roof) - Analysis of open structures without roofs
Wind Map - Basic wind speed map (Figure 6-1 of ASCE 7-05 Code)
Program Assumptions and Limitations:
1. Worksheet for "Simplified" analysis is applicable for low-rise buildings meeting the criteria of Section 6.4.1.
2. In the worksheet for Simplified analysis, the design MWFRS wind load is calculated for each direction. The design MWFRS load is assumed to be the total wind load on either the width or the length of the building respectively.
3. Worksheet for "MWFRS (Low-Rise)" is applicable for low-rise buildings as defined in Section 6.2.
4. Worksheets for "MWFRS (Any Ht.)", "Wall C&C", and "Roof C&C" are applicable for buildings with mean roof heights of up to 500 feet.
5. In worksheets for "MWFRS (Any Ht.)", "Wall C&C", and "Roof C&C" the user may opt to utilize user designated steps in height, 'z', in determining the wind pressure distribution.
6. Worksheets for "MWFRS (Any Ht.)", "Stacks & Tanks", and "Open Structures" can handle “rigid” as well as “flexible” buildings and structures. For “rigid” buildings or structures, this program uses the smaller value of either 0.85 or the calculated value from Section 6.5.8.1 of the Code for the gust effect factor, 'G'. For “flexible” buildings or structures, this program calculates the gust effect factor, ‘Gf’, per Section 6.5.8.2 of the Code based on the assumed formula for the fundamental period of vibration from Section 12.8.2.1 of the Code, where the exponent 'x' in the formula T = Ct*h^x is assumed to be 0.75.
7. Worksheets for "Wall C&C" and "Roof C&C" are applicable for flat roof buildings, gable roof buildings with roof angles <= 45 degrees, and monoslope roof buildings with roof angles <= 3 degrees.
8. Worksheet for "Stacks & Tanks" is applicable for cantilevered structures up to 600 feet tall.
9. Worksheet for "Open Structures" is applicable for open structures without roofs up to 500 feet tall. This can be utilized for open process-type structures as well as pipe/utility racks and bridges.
10. This program uses the equations listed in the reference, “Guide to the Use of the Wind Load Provisions of ASCE 7-02” for determining the external wind pressure coefficients, ‘GCp’, used in the Wall C&C and Roof C&C worksheets. (Note: a version of this document applicable to the ASCE 7-05 Code was not available.)
11. This program contains numerous “comment boxes” which contain a wide variety of information including explanations of input or output items, equations used, data tables, etc. (Note: presence of a “comment box” is denoted by a “red triangle” in the upper right-hand corner of a cell. Merely move the mouse pointer to the desired cell to view the contents of that particular "comment box".)
Useful Web Resource
I was given a couple of websites which you might find convenient for determining the basic wind speed and ground snow load
for any location in the continental United States per the ASCE/SEI 7-05 Code, so I thought I'd pass them along.
The website links are as follows:
Calculation Preview
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Just kidding, great workbook, much used.
That formula is f = 0.56/h^2*SQRT(E*I/m). The inverse of the frequency value is then taken to arrive at the period, "T". Also of note, this same formula is used in the Fluor Structural Guideline 000.215.1215, "Wind Load Calculation".
In the past, I had been using the rather simplistic and approximate formula from ASCE 7-05 of T = Ct*h^(3/4) for the period. The main issue with having used this formula is that there is no accounting for varying the diameter (width) of a vessel in determining the period.
Also, I have corrected some minor "typo" errors in a few of the worksheets
This workbook is now version 1.4.
I was given a couple of websites which you might find convenient for determining the basic wind speed and ground snow load
for any location in the continental United States per the ASCE/SEI 7-05 Code, so I thought I'd pass them along.
The website links are as follows:
http://www.windspeedbyzip.com/
http://www.groundsnowbyzip.com/
You must register to make use of either website, but you only have to register at one, not both of the websites.
Once you register at one of them, you will automatically have access to information from the other one.
The two websites allow you to input either the street/city/state address or just the zip code.
The resulting location latitude and longitude are given. Regular (street), satellite, and hybrid maps are available as well.
Since I'm still a practicing structural engineer, I tend to write spreadsheets on topics based on my experience to be used as tools to facilitate my own work.
Thanks for the kind words. I've fallen WAY behind as far as the various code changes are concerned. Since I still work, I create these spreadsheet workbooks predominantly in my spare time, which there never seems to be enough of. Retirement for me is hopefully within the next year, and thus with much more free time on my hands, I plan to stay active with the workbooks and make the attempt to stay more current with the codes.
As far as the ASCE 7-10 wind workbook is concerned, David Taylor (a contributor on this website) has taken my ASCE 7-05 workbook and basically updated it to ASCE 7-10. You might want to check that out.
Alex