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Pine Ridge Indian Reservation is in need of several thousand houses to alleviate overcrowding and improve living conditions. The United States government has failed to provide appropriate or sufficient housing and other individuals and organizations that have attempted to build homes for the Lakota have met with widely varying results. This paper documents community-based housing activities of fifteen Pine Ridge residents who attempted to implement a variety of construction techniques. The biggest challenges were obtaining and paying for resources and finding competent, reliable labor. The interviewees used local and salvaged materials extensively and worked within the local, informal economy to meet these challenges and address their dissatisfaction with government cluster housing. Findings suggest that local, community-based construction may provide a successful and culturally sustainable strategy for residential construction because it equips builders with a means to earn a living, develops construction skills, establishes a sense of ownership, and provides appropriate housing that enriches lives and builds pride.

Pine Ridge Indian Reservation is in need of several thousand houses to alleviate overcrowding and improve living conditions. The United States government has failed to provide appropriate or sufficient housing and other individuals and organizations that have attempted to build homes for the Lakota have met with widely varying results. This paper documents community-based housing activities of fifteen Pine Ridge residents who attempted to implement a variety of construction techniques. The biggest challenges were obtaining and paying for resources and finding competent, reliable labor. The interviewees used local and salvaged materials extensively and worked within the local, informal economy to meet these challenges and address their dissatisfaction with government cluster housing. Findings suggest that local, community-based construction may provide a successful and culturally sustainable strategy for residential construction because it equips builders with a means to earn a living, develops construction skills, establishes a sense of ownership, and provides appropriate housing that enriches lives and builds pride. (Contains 9 tables and 48 notes.)

Dynamic site characterization was performed at 25 sites located on the western portion of the Mexico City Basin that were severely damaged during the Mw7.1 2017 Puebla-Morelos, Mexico, earthquake. Testing was conducted using active and passive seismic surface wave methods and the microtremor horizontal-to-vertical spectral ratio method to determine site periods and develop one-dimensional (1D) shear wave velocity (Vs) profiles for the first 60 m of the subsoil. The measured site periods were compared to site period maps developed in 2004 and 2020 along with values computed using the Design Seismic Actions System (SASID) software following the 2020 version of the Complementary Technical Norms for Seismic Design (NTCDS). The most noticeable biases in the predictions from the 2004 site period map were observed between the boundary of Zone II and Zone IIIa, at which site periods are overestimated. These estimates were improved upon in the 2020 site period map and showed a close similarity with SASID computed site period values. The Vs, depth, and thickness of the lacustrine clay layer were also determined to be quite variable within the basin. The softest sites are located between the lakebeds with a Vs between 45 and 57 m/s. Sites located toward the outer rim of the North lakebed have a higher Vs between 80 and 100 m/s. The thickness of the clay layer varies significantly in the western side of the Basin with values ranging between approximately 3 and 34 m. Overall, the results of this study indicate good agreement with the model embedded in the SASID software. The results (1) emphasize the need to regularly monitor changes that occur over time in the lacustrine clay layer, (2) complement the development of models that improve our understanding of wave propagation within the Basin, and (3) update and improve Mexico City's Norms. [ABSTRACT FROM AUTHOR]

An experimental study of the fundamental period of vibration of geologic strata above multiple impedance contrasts is presented for the Canterbury Plains, a deep, complex sedimentary basin on the South Island of New Zealand. Microtremor Horizontalto-Vertical Spectral Ratio (mHVSR) analysis was used at 152 locations to investigate the fundamental period of the strata above three significant impedance contrasts in the region: the Riccarton Gravel, the Banks Peninsula volcanic (BPV) rock, and the deep gray-wacke basement bedrock. Up to three mHVSR peaks were observed in many of the mHVSR curves, with the long-period (2-7 s) peaks controlled by the BPV and/or the underlying bedrock. As the thickness of the BPV increases, the response of the geologic strata above the basement bedrock was masked by the shallower BPV, effectively changing the definition of what constitutes the reference condition (i.e. engineering bedrock) for site response analyses. The mHVSR peaks matched the long-period amplification peaks observed in the response spectra calculated from ground motions recorded during the Canterbury Earthquake Sequence events, underscoring the importance of the identification and consideration of deep impedance contrasts in site classification. [ABSTRACT FROM AUTHOR]