Page 125 - AERB

7.9.4 Numerical Analysis of Multi-level Excavation in the heave on account of re-filling with soil-cement mix
Alluvial Soil and Impact of Multiple Buildings is shown in Fig. 7.29. Detailed SSI analysis of safety
on Settlement: A Case Study of GHAVP Site related structures also taking into account the residual
effect of excavation phenomena is under progress.
Excavation at NPP sites involves large area with
multiple levels of excavated bed for founding structures 7.10 AERB FUNDED SAFETY RESEARCH
at different depths. Due to removal of overburden PROGRAMME
during excavation, stress is relieved from the soil below
the foundation. Consequently, to the extent that the soil AERB promotes and funds research in radiation
behaves elastically, the soil beneath the excavation and safety and industrial safety. AERB Committee for Safety
adjacent ground tend to move upward called ‘Heave’. Research Programmes (CSRP) frames guidelines for the
A study of this phenomena considering the excavation same and also evaluates, recommends grants for research
for GHAVP, Haryana site is carried out. projects and monitor their progress periodically. During
this period, CSRP recommended four new projects. It
In the analysis, a detailed FE model of the soil also approved the renewal of ten ongoing projects. The
(~750mX650mX200m), excavation, and ground details are given in Tables 7.1 and 7.2.
improvement (GI) layer is developed using site specific
geotechnical properties. A sequential analysis involving AERB also provides financial assistance to
simulation of Geostatic stress state, removal of excavated Universities, Research Institutions and Professional
soil up to the excavation depth and soil-cement re- Associations for holding symposia and conferences on
filling (using sub-merged density of material) up to the the subjects of interest to AERB. During this period,
founding depth is undertaken. Initial geostatic state of financial assistance was provided to 34 Seminars,
stress, heave of the excavated bed, and reduction of Symposia and Conferences.

Geostatic State of Stress before Excavation Heave of the Excavated Bed (Plan) Residual Heave after GI Filling (Plan)
(Isometric view)
Fig. 7.29: Results of Multilevel Excavation Analysis

Table 7.1: New Research Projects Approved

S. Principal
No. Project Title Investigator Organisation
1 Experimental and Numerical Evaluation of Double Containment Dr. Mohd. IIT Roorkee
Structures of Indian PHWR against Hard Missile Impact due to Ashraf Iqbal
External Event
2 Molten Corium Concrete Interaction Studies Dr. Arunkumar IIT Bombay, Mumbai
Sridharan
3 Assessment of Liquefaction Potential through Analytical Methods Dr. S. D. Anitha M. S. Ramaiah University of
Kumari Applied Sciences, Bangalore
4 Performance Evaluation of Generic Compounds with Effective Dr. Shweta Thapar Institute of Engineering
Functional Group as Corrosion Inhibitors for RC Structures Goyal & Technology, Patiala

AERB Annual Report 2019 97