Determination of Seasonal Soil Strength by                  Spectral-Analysis-of-Surface Waves
{'Code': '07030000', 'Directorate': {'Abbreviation': 'ENG', 'LongName': 'Directorate For Engineering'}, 'Division': {'Abbreviation': 'CMMI', 'LongName': 'Div Of Civil, Mechanical, & Manufact Inn'}}
{'SignBlockName': 'La Tanya Darby', 'PO_EMAI': None, 'PO_PHON': None}
A serious problem related to evaluation of soil strength is the                 lack of knowledge related to seasonal variation of soil                         properties.  Geotechnical engineers have recognized this problem                and have established various corrections.  However, these methods               are generally empirical and cannot truly represent the conditions               at a specific site.  What is needed is a better technique to                    determine the time dependent change of soil properties.  One                    technique that is available, but largely untried, is based on                   spectral-analysis-of-surface waves (SASW) to determine shear wave               velocities and depths of frozen layers.  Shear wave velocities                  can then be related to soil moduli that can be used in                          conventional engineering analysis.  This work applies SASW                      techniques to a series of tests at different times during a year.                                                                                               The results will show that this technique can be used to assess                 seasonal effects on soil parameters and should demonstrate the                  technique as a reliable method of evaluating a large number of                  test sections in a short time.  As part of the test program, a                  refraction survey of the test sites and a series of Clegg Impact                tests will be conducted at the same time and place as the                       spectral analysis.  This should provide independent tests that                  can be related to the results from the spectral analysis.
{'FirstName': 'Bernard', 'LastName': 'Alkire', 'PI_MID_INIT': 'D', 'PI_SUFX_NAME': None, 'PI_FULL_NAME': 'Bernard D Alkire', 'EmailAddress': None, 'NSF_ID': '000323489', 'StartDate': '02/15/1989', 'EndDate': None, 'RoleCode': 'Principal Investigator'}
{'Name': 'Michigan Technological University', 'CityName': 'HOUGHTON', 'ZipCode': '499311200', 'PhoneNumber': '9064871885', 'StreetAddress': '1400 TOWNSEND DR', 'StreetAddress2': None, 'CountryName': 'United States', 'StateName': 'Michigan', 'StateCode': 'MI', 'CONGRESSDISTRICT': '01', 'CONGRESS_DISTRICT_ORG': 'MI01', 'ORG_UEI_NUM': 'GKMSN3DA6P91', 'ORG_LGL_BUS_NAME': 'MICHIGAN TECHNOLOGICAL UNIVERSITY', 'ORG_PRNT_UEI_NUM': 'GKMSN3DA6P91'}
{'Name': None, 'CityName': None, 'StateCode': None, 'ZipCode': None, 'StreetAddress': None, 'CountryCode': None, 'CountryName': None, 'StateName': None, 'CountryFlag': None, 'CONGRESSDISTRICT': None, 'CONGRESS_DISTRICT_PERF': '""'}
{'Code': '1448', 'Text': 'GEOTECHNICAL I'}
{'url': 'https://www.nsf.gov/awardsearch/download?DownloadFileName=1988&All=true', 'xml': '8820172.xml'}