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How to Use ArcView GIS in an Analysis of Seismic Risk

Opening a project file

1.  Double click on the Arcview Icon  in the GIS and Imaging Group.
2.  Open the file www-risk.apr in the path  h:\resources\gis-projects\www-risk.apr

Tools to manipulate your view

1.  A colorful map of Sehome Hill geology will come up with campus buildings and streets.

2.  To zoom in, click once on the zoom-in tool , click and drag a box around the area and release.  To zoom out, use the "zoom to previous extent"  button,  or the "Zoom to full extent" button .

3.  The image can be moved around using the hand tool..  Patiently wait for the white space to fill.

4.  You may choose to turn on or off other themes.  Click on the box next to Contours in the legend to see how this works.

Determining Building Numbers and exploring geology

1.  One way to identify building number, road names or aspects of  geology is to use the "information tool."   To determine the building id number, first Highlight the area in the legend around the label "Buildings," so it is raised.  Click once on the information button.   Click exactly on the building of interest and it will produce a spreadsheet with information about that building. Notice the row that says: Bldg_id.
2. You can use the information tool to explore geology also, but first click on the gray area in the legend around the word "geology."  Move your mouse over the image and click once on a certain color.  You'll see a simple spreadsheet with a lot of information about that geologic surface material.
3.  Scroll down to read about the basic Material, it's response to seismic shaking and its GSM rating.
4.  Another way to explore geology is to use the hot-link tool.   Click once on this, move your mouse over the image and click once on a certain color.  A text file will come up that explains the geologic origin  and seismic response in more detail. Most important for your building assessment is the GSM rating which is listed on the bottom.
5.  You may view an "attribute table" about any of the themes. An attribute table is a tabular database that organizes "attributes" of that theme.  First click in the gray space in the legend to raise the area around the theme's name. Then click on the "Open Theme Table" button 

Analyzing buildings

To analyze the seismic risk of buildings their Theme Attribute Table must be filled with the descriptors that would be variables in the analysis.  When this has been accomplished you may conduct the following analyses below.
 

Analysis #1: Create color gradations based on overall  RVS rating
1. Double click on the colored square under the word buildings in the legend.
2. Select "graduated color" as legend type and  "Rvs_rating" as the Classification field. Noticed the color gradation can be flipped so small numbers can be darker.
3. Select choices under the "Classify" button to tailor the display.

Analysis #2: Graphically view building types
1. Click on the query building tool .  Type or click in:  [Building Materials = "urm"].
2.  Click OK and notice that the only highlighted buildings on the view are those made of unreinforced masonry.
3.  Click on the Attribute Table button,  highlight the Building Materials column and click on summarize. This will produce a new table with which you can graph other attributes of these buildings (e.g. overall ratings or overhang risk).
4.  Alternatively you could click on the Attribute Table button, then click on the Promote button  and read the details of that set.  To return to the View, select it (WWU Map) from the Windows pull down menu.
5.  To de-select a group of buildings, click on "Clear selected features" under Theme (in the view), or Select None under Edit (at the Attribute Table).

Analysis #3:  Determine the percentages of building types.
1.  To analyze the buildings in a different way, switch to the view, high light buildings in the legend and draw a box around all buildings using the select tool .
2.  Switch back to the attribute table. Notice that all records are highlighted.
3.  Select  the Building Materials column and click on the summarize button. This will create a new table that counts the various types of buildings. This may be saved or made into a pie graph. Since some buildings are un-rated, one of the records (the largest) will not have a building type designated.
4.  To make a pie graph that ignores un-rated buildings that record must be deleted. To edit the attribute table select "Start Editing," under the "Table" pull down menu.  Highlight that record and select "Delete Record" Under "Edit."

Analysis #4:  Output a list of buildings that rest on the peat bog.
1.  To analyze the buildings that are on the worst geologic surface material select the Peat Layer  by clicking within it. Be sure to highlight Geology in the legend first.
2.  Highlight the Buildings theme in the legend.
3.  Select "Select by Theme" under the "Theme" pull down menu. Set the options as shown below. Notice in the view that only buildings resting on the selected geologic surface material are highlighted.
4.  In the Theme Attribute Table, this group may be promoted , summarized  and graphed.

1.  After you have your map framed how you want it, select LAYOUT, under the VIEW pull down menu.
2.  The image will be positioned within a frame.  Its size and location may be manipulate.  By clicking on the T button once, and then on the title it may be rewritten.
3. Text may be inserted anywhere else on the image in a similar manner.  First click on the T button, then click in any location.  To enlarge, shrink or relocate text use the arrow button.
4.  Various map features (scale, key and north arrow) may be altered or moved).
5. To save an image, select EXPORT under the FILE menu. Change the file type to Windows Bitmap select the network path.