The overall scope of the project is to complete an up-to-date comprehensive analysis of record of the SDT System at Hanford. The "Double-Shell Tank (DST) Integrity Project - DST Thermal and Seismic Project" is in support of Tri-Party Agreement Milestone M-48-14.

The overall scope of the project is to complete an up-to-date comprehensive analysis of record of the DST System at Hanford. The "Double-Shell Tank (DST) Integrity Project - DST Thermal and Seismic Project" is in support of Tri-Party Agreement Milestone M-48-14.

The essential difference between Revision 1 and the original issue of this report is the analysis of the anchor bolts that tie the steel dome of the primary tank to the concrete tank dome. The reevaluation of the AP anchor bolts showed that (for a given temperature increase) the anchor shear load distribution did not change significantly from the initially higher stiffness to the new secant shear stiffness. Therefore, the forces and displacements of the other tank components such as the primary tanks stresses, secondary liner strains, and concrete tank forces and moments also did not change significantly. Consequently, the revised work in Revision 1 focused on the changes in the anchor bolt responses and a full reevaluation of all tank components was judged to be unnecessary.

The essential difference between Revision 1 and the original issue of this report is in the spring constants used to model the anchor bolt response for the anchor bolts that tie the steel dome of the primary tank to the concrete tank dome. Consequently, focus was placed on the changes in the anchor bolt responses, and a full reevaluation of all tank components was judged to be unnecessary. To confirm this judgement, primary tank stresses from the revised analysis of the BES-BEC case are compared to the original analysis and it was verified that the changes are small, as expected.

This report summarizes the results of the Double-Shell Tank Thermal and Operating Loads Analysis (TaLA) combined with the Seismic Analysis. This combined analysis provides a thorough, defensible, and documented analysis that will become a part of the overall analysis of record for the Hanford double-shell tanks (DSTs). The bases of the analytical work presented herein are two ANSYS{reg_sign} finite element models that were developed to represent a bounding-case tank. The TaLA model includes the effects of temperature on material properties, creep, concrete cracking, and various waste and annulus pressure-loading conditions. The seismic model considers the interaction of the tanks with the surrounding soil including a range of soil properties, and the effects of the waste contents during a seismic event. The structural evaluations completed with the representative tank models do not reveal any structural deficiencies with the integrity of the DSTs. The analyses represent 60 years of use, which extends well beyond the current date. In addition, the temperature loads imposed on the model are significantly more severe than any service to date or proposed for the future. Bounding material properties were also selected to provide the most severe combinations. While the focus of the analyses was a bounding-case tank, it was necessary during various evaluations to conduct tank-specific analyses. The primary tank buckling evaluation was carried out on a tank-specific basis because of the sensitivity to waste height, specific gravity, tank wall thickness, and primary tank vapor space vacuum limit. For this analysis, the occurrence of maximum tank vacuum was classified as a service level C, emergency load condition. The only area of potential concern in the analysis was with the buckling evaluation of the AP tank, which showed the current limit on demand of l2-inch water gauge vacuum to exceed the allowable of 10.4 inches. This determination was based on analysis at the design waste temperature of 350 F and the full 60-year corrosion allowance on the tank wall of 0.060 inch. However, analysis at a more realistic temperature of 250 F or corrosion allowance of 0.025 inch results in an acceptable demand/capacity ratio according to the ASME code criteria. Thus, buckling of the primary tank is judged to be unlikely for the current lack of corrosion in the tanks, and the expectation that the maximum waste temperature will not exceed 210 F. The reinforced concrete structure was evaluated as specified by the American Concrete Institute (ACI) code requirements for nuclear safety-related structures (ACI-349). The demand was demonstrated to be lower than the capacity at all locations. Revision 1 is being issued to document changes to the anchor bolt evaluation. RPP-RPT-32237 Rev. 1, Hanford Double-Shell Tank Thermal and Seismic Project-Increased Liquid Level Analysis for 241AP Tank Farms, described changes to the anchor bolt modeling and evaluation which were implemented in response to the independent reviewer's comments. Similar changes have been made in the bounding tank analysis and are documented in RPP-RPT-28968 Rev. 1. The conclusions of the previous releases of this report remain unchanged.

The work reported in this document was performed in support of a project entitled ''Double-Shell Tank (DST) Integrity Project - DST Thermal and Seismic Analyses''. The overall scope of the project is to complete an up-to-date comprehensive analysis of record of the DST System at Hanford. The work described herein was performed in support of the seismic analysis of the DSTs. The thermal and operating loads analysis of the DSTs is documented in Rinker et al. (2004). The work herein was motivated by review comments from a Project Review Meeting held on March 20-21, 2006. One of the recommendations from that meeting was that the effects of the interaction between the tank liquid and the roof be further studied (Rinker, Deibler, Johnson, Karri, Pilli, Abatt, Carpenter, and Hendrix - Appendix E of RPP-RPT-28968, Rev. 1). The reviewers recommended that solutions be obtained for seismic excitation of flat roof tanks containing liquid with varying headspace between the top of the liquid and the tank roof. It was recommended that the solutions be compared with simple, approximate procedures described in BNL (1995) and Malhotra (2005). This report documents the results of the requested studies and compares the predictions of Dytran simulations to the approximate procedures in BNL (1995) and Malhotra (2005) for flat roof tanks. The four cases analyzed all employed a rigid circular cylindrical flat top tank with a radius of 450 in. and a height of 500 in. The initial liquid levels in the tank were 460,480,490, and 500 in. For the given tank geometry and the selected seismic input, the maximum unconstrained slosh height of the liquid is slightly greater than 25 in. Thus, the initial liquid level of 460 in. represents an effectively roofless tank, the two intermediate liquid levels lead to intermittent interaction between the liquid and tank roof, and the 500 in. liquid level represents a completely full tank with no sloshing. Although this work was performed in support of the seismic analysis of the Hanford DSTs, the tank models in this study are for an idealized flat top configuration. Moreover, the liquid levels used in the present models are for study purposes only and are independent of the actual operating levels of the DSTs. The response parameters that are evaluated in this study are the total hydrodynamic reaction forces, the peak convective hydrodynamic forces, the fundamental convective frequencies, the liquid pressures, and peak slosh heights. The results show that the Dytran solutions agree well with the known solutions for the roofless tank and completely full tank. At the two intermediate liquid levels, there are some significant differences between the Dytran results and the approximate estimates. The results show that the estimates of peak hydrodynamic reaction forces appearing in BNL (1995) and Malhotra (2005) are reasonable and generally conservative relative to the Dytran solutions. At the 460 and 480 in. liquid levels, Dytran underestimates the convective component of the reaction force compared to the estimated in BNL (1995) and Malhotra (2005), but the convective component of the reaction force is small relative to the total reaction force. At the 490 in. liquid levels, the peak convective reaction force is more than twice as large as predicted by the approximate methods in BNL (1995) and Malhotra (2005). All three methods give similar answers for the fundamental convective frequency at the 460 and 480 in. liquid levels, but the Dytran solution indicates a significant increase in the apparent convective frequency at the 490 in. liquid level that is caused by the interaction with the roof. The peak wall pressures in the tank at the two intermediate liquid levels are essentially the same as for a roofless tank in the lower two-thirds of the tank wall, but diverge from that solution in the upper third of the tank wall. The estimates of peak wall pressures appearing in BNL (1995) are quite conservative lower in the tank, but may underestimate the peak wall pressures closer to the tank roof. Finally, the peak roof pressures predicted by Dytran at the 480 and 490 in. liquid levels are approximately twice as large as those predicted using the methodology of Appendix D of BNL (1995) and are ten to twenty times higher than predicted using the simple hydrostatic approach in Malhotra (2005).

M & D Professional Services, Inc. (M & D) is under subcontract to Pacific Northwest National Laboratory (PNNL) to perform seismic analysis of the Hanford Site double-shell tanks (DSTs) in support of a project entitled ''Double-Shell Tank (DSV Integrity Project--DST Thermal and Seismic Analyses)''. The overall scope of the project is to complete an up-to-date comprehensive analysis of record of the DST system at Hanford in support of Tri-Party Agreement Milestone M-48-14, The work described herein was performed in support of the seismic analysis of the DSTs. The thermal and operating loads analysis of the DSTs is documented in Rinker et al. (2004). The work statement provided to M & D (PNNL 2003) required that the seismic analysis of the DSTs assess the impacts of potentially non-conservative assumptions in previous analyses and account for the additional soil mass due to the as-found soil density increase, the effects of material degradation, additional thermal profiles applied to the full structure including the soil-structure response with the footings, the non-rigid (low frequency) response of the tank roof, the asymmetric seismic-induced soil loading, the structural discontinuity between the concrete tank wall and the support footing and the sloshing of the tank waste. The seismic analysis considers the interaction of the tank with the surrounding soil and the effects of the primary tank contents. The DSTs and the surrounding soil are modeled as a system of finite elements. The depth and width of the soil incorporated into the analysis model are sufficient to obtain appropriately accurate analytical results. The analyses required to support the work statement differ from previous analysis of the DSTs in that the soil-structure interaction (SSI) model includes several (nonlinear) contact surfaces in the tank structure, and the contained waste must be modeled explicitly in order to capture the fluid-structure interaction behavior between the primary tank and contained waste.