Utilities

This page contains four programs designed to convert existing strong-motion files into different forms. When any of the programs is selected, a brief description of what is does appears in the box at the bottom of the screen.

"Convert cm/s/s to g's" converts a file containing a sequence of accelerations in units of cm/s/s into a file containing a sequence of accelerations in units of g. The program simply divides each value of cm/s/s by 980.665 to obtain values in terms of g.

"Convert g's to cm/s/s" converts a file containing a sequence of accelerations in units of g into a file containing a sequence of accelerations in units of cm/s/s. The program simply multiplies each value by 980.665 to obtain values in cm/s/s.

"Multiply by Constant" multiplies the values in a file by a user-specified constant. The constant is specified in the "Constant" field. This program is useful for files that contain values in units other than g's or cm/s/s that need to be converted to cm/s/s for use in the Newmark program.

"Redigitize" converts a time file (a file containing paired time and acceleration values) into a file containing a sequence of acceleration values having a constant time spacing (digitization interval) using an interpolation algorithm. The digitization interval for the output file must be specified in the "Digitization interval" field; any value can be selected by the user, but values of 0.01-0.05 generally are appropriate. The output (destination) file is in the format necessary to run the other programs in this package, but if the original time file had units other than cm/s/s, it will be necessary to convert to cm/s/s before adding the file to the database in the "Record Manager".

Utility programs can be run on individual files or on all files in a specified directory. For any program selected, the path name for the source file or directory is specified in the box under "Source file or directory" or selected using the adjacent browser window. The file and path name for the destination file or directory are similarly specified or selected with the browser in the box under "Destination file or directory". If a source file contains header information, specify the number of lines in the header in the "Skip the first ___ lines of the source file" box. This will create a destination file that contains only acceleration values and no header information, which is the required format for adding a record to the database in the "Record Manager". If a record contains acceleration values in the correct form (units of cm/s/s) but contains header information that needs to be removed, use the "Multiply by a constant" option, specify a constant value of 1, and specify the number of lines in the header; a new file will be created with the header removed and the data values unchanged.

When all of the input boxes have the required data entered, click on the "Execute" button to execute the program. The destination file will be written to the location specified. If a file with the name specified in the "Destination file" box already exists, the program automatically overwrites the original file.