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Liquefaction-induced lateral spreading can induce significant deformations and damage in existing structures, such as ports, bridges, and pipes. Past earthquakes have caused this phenomenon in coastal areas and rivers in many parts of the world. Current lateral spreading prediction models tend to either overestimate or underestimate the actual displacements by a factor of two or more when applied to large subduction earthquake events. The purpose of this study was to identify ground motion intensity measures and soil parameters that better correlate with observed lateral spreading under large-magnitude (Mw ≥ 7.5) subduction earthquakes that have occurred in countries like Chile, Japan, and Peru. A numerical approach was first validated against centrifuge and historical cases and then used to generate parametric models on which statistical analysis was applied. Our results show that cumulative absolute velocity (CAV), Housner intensity (HI), and sustained maximum velocity (SMV) have a reasonably good correlation with lateral spreading for the analyzed cases.

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The California Bearing Ratio (CBR) is a method for the relative quality of the subgrade, subbase and base of a pavement evaluation throughout an essay on the field or laboratory and also pavement design. The most common is CBR soaked, nevertheless, obtaining its value is expensive and time consuming. The main objective of this research is correlating CBR with some index properties of soils of easy evaluation: percentage of gravel (G), percentage of sand (S), percentage of fine (F), liquid limit (LL), plastic limit (PL), plastic index (PI), optimal moisture content (OMC) and maximum dry density (MDD); to propose an alternative method to obtain the CBR value. For this research, simple and multiple correlation using Microsoft Excel was applied in a total of 75 samples of granular and clayed soils from Piura city, obtained from a local laboratory's records.

The main objective of this research is to present a review about methods of analysis and mitigation in soil liquefaction, especially in those of sandy and loose density soils. The experience of different researchers shows that the most suitable methods of analysis are those that are based on "in situ" tests data while preserving the soil properties, especially those based on the use of SPT (Standard Penetration Test) because of the greatest existing data. Likewise, the most suitable mitigation methods is using gravel drains due to several advantages that improve liquation resistance, increasing the densification of soil, improving the drainage (quickly dissipates the interstitial pressures in an earthquake) and reduces cyclical tangential stress (which contributes to liquefaction) due to flexibility of the gravel pack.