September 13, 2019

Partial Correlation and Dependence Between Seismic Fragilities of Multiple Adjacent Structures with Significant Soil-Structure-Interaction Effects

By: Mohamed Talaat, Robert P. Kennedy

Seismic Probabilistic Risk Assessment (SPRA) of nuclear power plants (NPPs) is typically performed using three major analysis components: probabilistic seismic hazard, seismic fragility, and plant response. The fragility analysis develops...

September 13, 2019

Case Study: Cable Tray Seismic Fragility Evaluation Involving Ductile Failure of a Cold-Formed Steel Section in Flexure

This paper presents a case study for a recent seismic fragility evaluation of cable trays at a nuclear power plant in the United States. The evaluation was initiated due to the presence of non-serrated strut nuts in cable tray supports throughout...

September 13, 2019

Reinforced Concrete Shear Wall Capacity Advances

Seismic PRAs have become more common in the nuclear power industry following the Fukushima accident caused by the 2011 earthquake and tsunami. In order to provide best estimates of the risk, the seismic fragilities should be as realistic as...

September 13, 2019

Nonlinear Response of a Structure with Significant Soil-Structure Interaction Effects for Application to Seismic Fragility Evaluation

By: Philip Hashimoto, Juan Jimenez-Chong, David Nakaki, Robert P. Kennedy

An important element of structure seismic fragility evaluation for seismic probabilistic risk assessment is determination of the inelastic energy absorption factor. This factor accounts for a structure’s ability to withstand earthquake...

September 13, 2019

Seismic Soil-Structure Interaction Analysis of an Embedded Structure with Partially Bonded Side-Soil

By: Cameron Samuelson-Sanford, Juan Jimenez-Chong, Mohamed Talaat, Philip Hashimoto, David Nakaki, Oleg Maslenikov, James J. Johnson

Seismic soil-structure interaction (SSI) analysis is performed for an embedded structure with partially bonded side-soil in support of the seismic probabilistic risk assessment of a nuclear power plant. Adjacent buildings with shallower embedment...

September 13, 2019

Effects of Boundary Conditions on PWR SNF Rod Stiffness and Stresses Under Pinching Loads

By: Ricardo Medina, Elmar Eidelpes, Luis F. Ibarra

The effects of rod boundary conditions (BCs) on the stiffness and cladding stresses of pressurized water reactor (PWR) spent nuclear fuel (SNF) rods under pinching loading are investigated. Pinching may occur at the assembly spacer grids during...

September 13, 2019

Seismic Fragility af Anchored Flat-Bottom Storage Tanks on Ring Foundations

By: Abhinav Anup, Philip Hashimoto, Robert P. Kennedy

Seismic fragility evaluations of anchored flat-bottom storage tanks typically follow the approaches outlined in EPRI (1991) and EPRI (1994a), which are intended for tanks founded on rigid mat foundations. Direct application of these approaches is...

September 13, 2019

A Hybrid SSI Analysis Method for Embedded and Partially Bonded Rigid Foundations

By: David Nakaki, Mohamed Talaat, Juan Jimenez-Chong, Cameron Samuelson-Sanford, James J. Johnson, Oleg R. Maslenikov

CLASSI and SASSI are two sub-structuring approaches to analyze the phenomena of soil-structure interaction (SSI) with extensive applications in the nuclear power industry. Many similarities exist in the two methods; both approaches treat the SSI...

September 13, 2019

Seismic Fragility Evaluation of Metal Flat-Bottom Storage Tanks with Short Anchor Bolt Chairs

By: Abhinav Anup, Ho Jung Lee, Philip Hashimoto, Robert P. Kennedy

Seismic fragilities of anchored metal flat-bottom storage tanks are usually governed by tank overturning. Tank overturning capacity is typically influenced more by the hold-down strength of the anchors rather than the buckling strength of the...

August 6, 2019

Survey Level Condition Assessment of Bar-Wrapped and Steel Pipe

By: Murat Engindeniz, Troy Bontrager, David Zavala, Paul Murray

There is a significant amount of AWWA C303 bar-wrapped pipe (BWP) and C200 steel pipe water transmission mains installed across the United States. While condition assessment of aging BWP lines has typically not received as much attention as some...