Assignment5_EarthquakeRisk_50_EMES101

EMES101.ALL Fall23 Assignment Grade: up to 12 points Group Contribution Grade: up to 3 points Assignment 5: Determining Earthquake Risk Group Number: Group Members Present (first and last names): Each group member present must WRITE THEIR OWN NAME above to earn credit for contributing to the assignment. Do not write the names of group members who are not present. Scribes’ initials: Share the scribe duty with everybody present. This means you must rotate who writes the answers to different questions. Once you’ve completed your scribe duty, initial above. You are part of a team of geologists for the USGS (U.S. Geologic Survey) tasked with determining areas of high seismic risk in the state of California using the following calculation: Risk = Hazard x Vulnerability x Value Where: hazard = the chance that the building will experience strong shaking vulnerability = the likelihood that the building will collapse due to earthquake hazards value = the number of lives potentially affected Your team previously identified San Francisco as being of one of the highest hazard areas in California; it lies within the San Andreas Fault Zone and has a high probability of a M7.0-7.9 earthquake occurring in the next 30 years. The city of San Francisco has passed a bond measure that will give $10 million each to retrofit 2 schools out of 5 or 6 that have the highest seismic risk. Your job is to conduct a risk assessment on 1 of the schools while other teams assess the others. Once teams compile and share their risk assessment data, you will determine which schools have the highest risk and make recommendations to the school board on how to delegate the $20 million dollars for seismic retrofitting. Learning objectives • Assess the risk for your school based on quantified values for hazard, vulnerability, and value. • Compare your results with other geologic teams and make a recommendation on which two schools should be retrofitted at a cost of $10 million each. Part 1: Determining Risk Examine the overview maps of the San Francisco area schools. Find each of the labeled schools on the San Francisco map. Your team of geologists will be assigned to examine one of the schools based on the data folder you receive. If you’re completing this digitally as an individual, your school is El Camino High School, and its data is in a downloadable file in Sakai’s Assignments tab. All groups and individuals will calculate risk using the using a scaled down version of the FEMA Rapid Screening Protocol for Buildings and

quantifying values for variables A-G: Risk = ( A + B + C ) 9 × ( D + E + F ) 3.5 ×G Where hazard consists of: Where vulnerability consists of: Where value consists of: A = peak ground acceleration D = soft stories G = population B = liquefaction potential E = unreinforced masonry C = landslide potential F = vertical or plan irregularity Tabulate the data for only your assigned school in the table below. Note that columns A-G correspond to the variables in the previous equation. You must write your answers in the table below to be graded; we will NOT grade your answers in the Google Sheet. (4 points, 0.5 points for each column). Hazard Vulnerabili ty Value Analysis School A : Peak Ground Acceleration B : Liquefactio n Potential C : Landslide Potential D : Soft Stories? E : Unreinforce d Masonry F : Vertical or Plan Irregularity G : Population Risk Factor R = [(A+B+C)/9] x [(D+E+F)/3.5] x G Marina Middle School Garfield Elementary School Francisco Middle School Herbert Hoover Middle School Guadalupe Elementary School El Camino High School Table 1. Complied data and risk analysis. Before continuing, refresh your team’s memory by revisiting the components of section 8.6 in your text on ground shaking, liquefaction, and seismically induced landslides. A. Peak Ground Acceleration The Strong Shaking Potential Map shows the peak ground acceleration that is 98% likely to occur in 50 years. The value of peak ground acceleration is a measure of the most violent shaking expected in a likely earthquake. The higher the acceleration, the stronger the shaking. Colors on the map correspond to peak ground acceleration in terms of the fraction of free-fall acceleration (“% g”). Values of % g associated with each color are listed on the map’s legend. Use the following categories to score your school’s location (from 1-3) based on the ground acceleration (% g) and, therefore, the seismic hazard due to strong shaking. Write your team’s determined score for variable A in column A on the Table 1.  <30% g: Low hazard = 1  30-60% g: Moderate hazard = 2  >60% g: Significant hazard = 3