The paper covers engineering studies undertook and likely preventive measures to be undertaken towards the critical boulders and steep slope surface stabilization around Ajanta caves: the UNESCO World Heritage site near Aurangabad in Maharashtra state of India. The slope failure and boulder dislocations due to the long-term rock mass deterioration, distressing, water percolation and weathering in Ajanta caves for a strike length of nearly 600m and a height of nearly 75m are a major concern considering the safety of the visitors/tourists, the site personnel's and also keeping in view the preservation of the historic heritage site. The slope stability and engineering geological condition of the cave area including geological setting, seepage and fractures is discussed. The various measures like epoxy resin/chemical based shotcreting and grouting, rock/anchor bolting, and wire meshing etc., is suggested keeping in view the principles of "restoration to historic condition and not altering the historic appearance".
The Ajanta caves are situated at a distance of 6.5 km from Fardapur, a village, 101 km in the northern direction of the Aurangabad district of state Maharashtra in India. The caves at Ajanta are excavated in the semi-circular scarp of a steep rock, about 76m high, overlooking a narrow sinuous gorge, through which flows the stream Waghora descending at the head of the ravine beyond Cave 28 in awaterfall of seven leaps, known as Sat-kund (Fig. 1). The cave layout with their indexing numbers is shown in Fig. 2.
The Ajanta cave areas have been listed as protected monuments in the UNESCOWorld Heritage list since 1983 due to its remarkable reserves of materials for studying Buddhist culture and the arts of the Far East. The Ajanta world heritage monuments are ancient rock-cut Buddhist caves excavated from 2nd century BC to 6th century AD. There are 30 caves in Ajanta carved in basaltic flowof the DeccanTraps in steep left bank ofWaghur River. The roof, sidewalls and rock pillars are made of the in-situ Deccan trap basalt. Another astonishing aspect of the caves suggests higher quality artisticwork from the chisel imprints marks left-out on the inner surfaces of the caves. The discovery of the Ajanta caves called the attention of many specialists in engineering geology, rock mechanics and other disciplines. The numerous studies reported in the literature and cited by Li et al (2009) also have revealed many highlights involved in excavation of the various caves found worldwide.