Strong motion earthquake accelerograms, digitized and plotted data, Volume I - uncorrected accelerograms; Part C - Accelerograms IC041 through IC055

The first set of 20 uncorrected digitized earthquake accelerograms was published in July, 1969 as Volume I, Part A of the present series. That volume also contained introductory material and background information describing the methods used, accuracies, etc. which should be referred to by all users of the data. Parts A and B have contained accelerograms from earthquakes dating from March 10, 1933, and are a portion of a complete series planned in 1969 covering all the important accelerograms to that time. The San Fernando Earthquake, however, provided more than twice as many records as previously available. In view of the importance of this earthquake, it was felt that we should interrupt the original plan and issue this and succeeding Parts containing San Fernando Earthquake accelerograms, before returning to the original series. The record from Pacoima Dam has received a great deal of attention. Included here are 42 seconds containing the main shock and the first clearly identifiable aftershock, together with six further aftershocks. Because of its importance and the high trace amplitudes involved, the Pacoima record was digitized from the original paper film. All the remaining paper film records were digitized from contactnegatives. Although most reproductions of the Pacoima record indicate some dim portions of the trace, the original trace was clearly distinguishable with no ambiguity. The special problems of this particular accelerogram are treated in the paper by Trifunac and Hudson listed in the references on page 5. The six portions of the Pacoima record containing the aftershocks have the following starting times, measured in seconds after the start of the main shock trace: 52. 6, 69. 6, 104. 6, 162. 0, 230. 1, and 309. 1 sec. These starting times are indicated by arrows on the reproduction of the Pacoima record appearing on page 6. Records from-buildings or arrays containing more than one instrument are included together in one. Part where possible. Part C contains records from Holiday Inn at 8244 Orion Blvd., L. A. , the Kajima Building at 250 E. First St., L. A. , (three records each) and the Union Bank at 445 Figueroa St., L. A. (two records.). As in previous reports the printout and plots contain asterisks and arrows, respectively, .indicating where the record was shifted in the digitizer when required. We should like to express our gratitude to personnel from the Jet Propulsion Laboratory who have assisted so capably on the digitizing: Miriam Blount, Jeannyne Gunkel, Jo Jean Kos, Carolyn Level and Florence Sims. In. addition we should like to thank our regular digitizers and assistants, students and otherwise, for their conscientious. work: N. R. Bacheliri, D. A. Blount, Esther Dizack, R. C. Dullien, H. H. Kwai, H. H. Law, V. W: Lee, M. Y. -C. Ngan, W. J. Raymond and K. K. Tung. We would also like to acknowledge the general support off the Earthquake Research Affiliates. The whole program has at all stages been conducted through the generous help of grants from the National Science Foundation, and- we have enjoyed the close cooperation of the staff of the Seismological Field Survey of the National Oceanic and Atmospheric Administration

Analyses of strong motion earthquake accelerograms, Volume IV - Fourier amplitude spectra; Parts N, O, and P - Accelerograms IIN185 to IIN197, IIO198 to IIO201, IIO213, IIP214 to IIP223, IIP231 and IIP232

For each earthquake accelerogram, two spectrum plots are given -- a Fourier amplitude spectrum versus frequency on a linear scale and a log-spectrum, log-frequency plot. In this Volume IV series, Fourier amplitude spectra will be given for all corrected accelerograms, including building response measurements. The corrected records analyzed in this report, Volume IV, Parts N, O, and P, appeared in Volume II, Part N, Report No. EERL 74-54, and Volume II, Parts O and P, Report No. EERL 74-55. Their uncorrected versions were published in Volume I, Part N, Report No. EERL 72-27; Volume I, Part O, Report No. EERL 73-20; and Volume I, Part P, Report No. EERL 73-21

Analyses of strong motion earthquake accelerograms, Volume IV - Fourier amplitude spectra; Parts Q, R and S - Accelerograms IIQ233 to IIQ243, IIR244 to IIR254, IIS255 to IIS273

The corrected records analyzed in this report, Volume IV, Parts Q, R, and S, appeared in Volume II, Parts Q and R, Report No. EERL 74-56, and Volume II, Part S, Report No. EERL 74-57. Their uncorrected versions were published in Volume I, Part Q, Report No. EERL 73-22; Volume I, Part R, Report No. EERL 73-23; and Volume I, Part S, Report No. EERL 73-24

Strong motion earthquake accelerograms, digitized and plotted data, Volume I - uncorrected accelerograms; Part E - Accelerograms IE071 through IE085

The first set of twenty uncorrected digitized earthquake accelerograms was published in July, 1969 as Volume I, Part A, of the present series. That volume also contained introductory material and background information describing the methods used, accuracies, etc. , which should be referred to by all users of the data. The San Fernando Earthquake provided records of such importance that the original plan was interrupted after two parts, and Part C contained the first of the San Fernando Earthquake accelerograms. This issue continues the San Fernando accelerograms and contains fifteen records consisting of three records each from four buildings, two records from Santa Felicia Dam and a ground record from Wheeler Ridge. Some comments on these records follow. IE071. Wheeler Ridge. The entire 30 second record was digitized. The time marks functioned for only two seconds, and therefore the paper speed was calculated from an average value during the preceding calibration test. IE072, 73, 74. 4680 Wilshire Boulevard, Basement, 3rd and 6th Floors. There is a hesitation of 0.2 second duration in the record in the basement during the first second of operation. Aligning this record with the other two may consequently require considerable care. IE075, 76, 77. 3470 Wilshire Boulevard, Sub-basement, 5th and 11th Floors. The sub-basement record was digitized on a different machine from that at Caltech and only 44 seconds could be handled. The upper floor records were digitized to 64 seconds, just short of the total record length. IE078, 79, 80. Los Angeles Water and Power Building, Basement, 7th and 15th Floors. The basement record was digitized to 57 seconds by which time the first aftershock had diminished. The upper floor records were digitized for a further 15 seconds. IE081, 82, Santa Felicia Dam, Outlet Works and Crest. Both records have been digitized the total length. IE082, 83, 84. 3407 Sixth Street, Basement, 4th Floor and Penthouse. The entire 60 second records were digitized. As in previous reports the printout and plots of those records that require shifting in the digitizer contain asterisks and arrows, respectively, indicating where such shifts occurred

Strong motion earthquake accelerograms, digitized and plotted data, Volume I - uncorrected accelerograms; Part I - Accelerograms 1I128 Through 1I140, Accelerograms from the San Fernando, California, earthquake of February 9, 1971

This issue continues the San Fernando accelerograms and contains thirteen records consisting of three each from buildings at the following addresses: 435 Oakhurst Avenue and 420 North Roxbury Drive in Beverly Hills; 1800 Century Park East and 15910 Ventura Boulevard in Los Angeles, and the record from the Borrego Springs Fire Department

Analyses of strong motion earthquake accelerograms, Volume IV - Fourier amplitude spectra; Parts V, W, and Y - Accelerograms IV294 to IV333, IIW334 to IIW336, IIW338, IIW339, IIW342 to IIW345, and IIY370 to IIY381

The corrected records analyzed in this report, Volume IV, Parts V, W, and Y, appeared in Volume II, Part V, Report No. EERL 75-52, and Volume II, Parts W and Y, Report No. EERL 75-53. Their uncorrected versions were published in Volume I, Part V, Report No. EERL 73-27; Volume I, Part W, Report No. EERL 73-28; and Volume I, Part Y, Report No. EERL 73-30

Analyses of strong motion earthquake accelerograms, Volume III - Response spectra; Part A - Accelerograms IIA001 through IIA020

This is the first volume of a series presenting earthquake response spectrum curves calculated from corrected ground accelerograms. An introduction summarizes response spectrum techniques in earthquake engineering as a background to the use of the data. For each earthquake accelerogram, two spectrum plots are given -- relative velocity response versus period on a linear scale, and a tripartite log-log plot giving relative displacement, pseudo-velocity, and pseudo-acceleration spectra. The Fourier spectrum plot is also shown on the linear plot. Digital print-outs of ordinates of the plotted curves are tabulated for each earthquake. The earthquakes in part A match the uncorrected accelerogram data of volume I and the corrected accelerogram data of volume II

Strong motion earthquake accelerograms, digitized and plotted data, Volume II - corrected accelerograms and integrated ground velocity and displacement curves; Part A - Accelerograms IIA001 through IIA020

None available

Strong motion earthquake accelerograms, digitized and plotted data, Volume I - uncorrected accelerograms; Part D - accelerograms ID056 through ID070

The first set of twenty uncorrected digitized earthquake accelerograms was published in July, 1969, as Volume I, Part A, of the present series. That volume also contained introductory material and background information describing the methods used, accuracies, etc., which should be referred to by all users of the data. The San Fernando Earthquake provided records of sufficient importance that the original plan was interrupted after two parts, and Part C contained the first of the San Fernando Earthquake accelerograms. This issue continues the San Fernando accelerograms and contains fifteen records consisting of three records each from four buildings, two ground level records at the Hollywood Storage Building and the record from the Old Ridge Route at Castaic. Some comments on these records follow. ID056. Castaic, Old Ridge Route. At 0.97 seconds after triggering the drive mechanism malfunctioned briefly and the film was stationary for a short length of time with the recording light on. The actual time is indicated by asterisks in the computer printout and by arrows in the computer plot. The lost portion of trace can be estimated to be one to two seconds long for the following reasons. The gap between the time marks is normally 0.5 seconds, but the particular gap spanning the missing part measures only 0.3 seconds. Hence at least 0.2 seconds is missing. In addition, at least one of the time marks occurred during the pause, so that the possible lengths of the pause are 0.7, 1.2, 1.7, 2.2, ... seconds. The maximum amplitudes of the missing traces can be ascertained from the thickness of the recorded vertical line for two of the three traces and these are less than the peak amplitudes occurring during the following one or two seconds. The changes in density along the recorded vertical line indicate that not a great many of the large oscillations of the trace took place during the pause and that a duration of 1.2 seconds is realistic. Also the records from the Lake Hughes Array Stations 4 and 12, within 26 km of Castaic, and a similar distance from the epicenter, 25-29km, indicate that the strong motion portion in this vicinity was only a few seconds in duration. These complete records show a marked similarity to that portion of the Castaic record outside the lost part, further confirming that not more than one or two seconds was lost. As another means of estimating the time lost, a laboratory test was made on the Castaic accelerograph in which the recording paper was held stationary for various time intervals with the recording light on, The intensities of the resulting traces were compatible with the above estimates. ID057, 58, Hollywood Storage Building, Basement and P. E, Lot. The total record length for the main shock is included. ID059, 60, 61, 1900 Avenue of the Stars, Subbasement, 9th and 21st Floors. The instrument on the 9th floor several times responded with a very high frequency, 80 - 100 cps, lightly damped oscillation, probably initiated by an impact loading on the structure near the instrument. Such impacts arise from dislodged material or equipment, or safety devices operating in elevator mechanisms. These were not digitized as part of the project. The instrument on the 21st floor operated for the same 58 - 60 seconds as the other two, but the first 11 seconds were not recorded. ID062, 63, 64. 1640 South Marengo Street, lst, 4th and 8th Floors. The 1st and 8th floor records were digitized to 54 seconds, by which time the first aftershocks had diminished. The 4th floor record was digitized to 98 seconds, for the total length of the record. ID065, 66, 67. 3710 Wilshire Blvd, Basement 5th and 10th Floors. The instrument on the 10th floor faces a different direction from the other two instruments and the component directions are therefore different. ID068, 69, 70. 7080 Hollywood Blvd., Basement 6th and 12th Floors. The total record length for the main shock is included. As in previous reports the printout and plots contain asterisks and arrows, respectively, indicating where the record was shifted in the digitizer. Two further reports (see References) have been issued at the California Institute of Technology describing the San Fernando Earthquake. "The Engineering Features of the San Fernando Earthquake, February 9, 1971" contains preliminary studies of some of the more important and interesting engineering features of the earthquake. The various chapters were prepared by staff and students working in Earthquake Engineering within the Division of Engineering and Applied Science. "Strong Motion Instrumental Data on the San Fernando Earthquake of February 9, 1971", a joint report with the Seismological Field Survey of the National Oceanic and Atmospheric Administration, U. S. Department of Commerce, presents an overall picture of the instrumentation results, updating and bringing together a number of preliminary reports issued by both the Earthquake Engineering Research Laboratory and the Seismological Field Survey. An account is given there of the performance of the Southern California strong motion networks, including the seismoscope results. Both of these reports are available from the National Information Service for Earthquake Engineering at the California Institute of Technology. We should like once again to express our gratitude to personnel from the Jet Propulsion Laboratory who earlier assisted so capably on the digitizing, and to our regular digitizers and assistants, students and otherwise, for their conscientious work. We would like to acknowledge the general support of the Earthquake Research Affiliates, the generous grants from the National Science Foundation and the cooperation of the Seismological Field Survey of the National Oceanic and Atmospheric Administration