The present study aims to examine thoroughly the relation between the local site effects and the local subsurface conditions in Lima city, due to the fact that there is little information related to the seismic amplification in this city. Using ground motion records, the amplification effects are studied empirically, in the frequency range from 0.1 to 20 Hz. This study analyzes the seismic events observed along the Pacific coast of Lima city, which were recorded by 10 stations.

Because of the limitation in data, site amplification factors are evaluated by using three different methods: the standard spectral ratio, the spectral inversion method and the H/V ratio, so as to identify the significant peaks and troughs at all sites. Results show that most of the stations present relatively large amplifications in the high-frequency range over 3 Hz, moreover RIN station. Nonetheless, CAL site has a different behavior of amplification.

The yield strength ratio concept, Su(yield)/σ’vo (Olson & Stark, 2003) and the cyclic strength ratio CRR (Seed et al, 1984) remain the main approaches of assessing triggering of liquefaction resistance for sloping ground. The Kα correction factor (Seed, 1983) has been extensively studied for considering the effect of the initial static stress on the triggering of liquefaction of sloping ground. Based on a suite of liquefaction triggering analyses, these most-commonly used cyclic stress methods, Seed et al. (2003)/Cetin et al. (2004) and Idriss and Boulanger (2008), are compared to the yield strength ratio approach (Olson and Stark 2003; Olson et al. 2006; Mesri 2007; and Olson and Zitny 2012), and the efficacy of the yield strength ratio is demonstrated. For validation of the comparison, one Mw 7.0 Haiti (2010) earthquake flow failures cases (North River near Dechapelle), (Olson et al., 2010) was selected to estimate the triggering of liquefaction and post-liquefaction resistance.

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Dynamic behavior of unreinforced masonry wall was investigated through a shaking table test in which two specimens were prepared. In order to simulate non-engineering houses of one story, the first specimen consists of a C shaped structure, whose masonry walls are connected only by their ends. The second specimen was built to idealize an upper story, therefore the C wall is connected at the top by a rigid diaphragm floor and a weight suspended. The test result show different behavior between each specimen. In the first specimen an out-of-plane failure mode governs and in second specimen a shear failure mode governs.