Baghdad Site Response Analysis for Temporal Dynamics and Seismic Intensity to Define Liquefaction Thresholds Onset
摘要
This study is focused on analyzing factors that affect liquefaction and which intensity and time duration will cause liquefaction in the soil in Iraq, especially in Baghdad. This work is concerned with assessing Baghdad soil liquefaction potential under actual earthquakes in Iraq with high-intensity effects when the intensity and period change. According to the U.S. Geological Survey, the intensity of earthquakes globally is not increasing. Also, the apparent increase in earthquake numbers is due to more seismic instruments being able to record more earthquakes, not because more earthquakes are happening. Human activities can indeed influence seismic activity and potentially trigger earthquakes. While these events are generally less potent than natural earthquakes, they can still be significant. Mining, dam building, and hydraulic fracturing (fracking) have been associated with induced seismicity. In the Baghdad region, the earthquake hazard is classified as medium, meaning there is a 10% chance of potentially damaging earthquake shaking within the next 50 years. However, it’s important to consider that various factors can affect seismic risk, including urban development, infrastructure resilience, and potential human-induced seismicity. In this study, the most extended software, PLAXIS 2D version 20, was used to assess the liquefaction potential of soil deposits under seismic loads. The analysis covered a comprehensive dataset of borehole sample test results, and information was gathered from various public and commercial entities throughout Baghdad. The main results showed that the soil of Baghdad is at risk of liquefaction of its soil and that the pore water pressure ratio will be equal to 1 at an intensity of 6 Ml and a time of 33 s.