Title:
Limit Analysis of Internally Pressurized Cut-and-Cover Type
Underground Reactor Containments
Author(s):
0. Mahrenholtz, D. V. Reddy, and W. Bobby
Publication:
Journal Proceedings
Volume:
79
Issue:
3
Appears on pages(s):
220-225
Keywords:
dynamic structural analysis; earthquake resistant structures; earthquakes;finite element method; loads (forces); nuclear reactor containment;pressure vessels; prestressed concrete; subsurface structures.
DOI:
10.14359/10901
Date:
5/1/1982
Abstract:
Ultimate load behavior of an in ternally pressurized cut-and-cover pres tressed concrete horseshoe-shaped containment is investigated for a loss-of-coolant type accident that can be triggered by an earthquake. Containment is in a clay medium with or without a stiffening (concrete/foam concrete/reinforced earth) jacket. The work is a con tin ua tion of previous in ves tiga tions that indicated favorable effects of embedment to internal pressurization and reinforced earth to seismic excitation. Sustained prestress alone and sustained prestress and static/dynamic internal pressure are considered. The prestress effect is simulated by an equivalent inward normal pressure at the containment’s centerline. The pulse used for dynamic analysis is similar to pulse due to a loss-of-coolant accident. The Drucker-Prager yield criterion is used for the concrete and soil, and reinforcement’s effect in the backfill is accounted for by adding its in-plane stiffness. Ultimate load values are determined by finite element analysis for various media patterns (concrete/foam concrete/reinforced earth/clay) using the computer code NONSAP. Dead loading’s effect is accounted for in evaluating dynamic response. The results confirm embedmen t’s favorable effects. Limitations and improvements of the material models used are indicated.