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Abstract: Cleats and fractures in coal of Barakar Formation in Jharia coalfield, India have been mapped from the coal exposures around 21 opencast and 2 underground coal mines. Macro-cleat distribution, observed from this mapping is similar to that of well-developed coalbed methane (CBM) basins. The opencast coal mines are distributed in SE–NW direction along the boundary of the sickle shaped Jharia coal basin. Permeability of CBM through coal seams is the most critical property deciding the viability of any CBM field. It is largely controlled by the degree of cleat development. This paper discusses cleat orientation and other structural features, observed in the outcrops of 14 major coal seams in Jharia coalfield and its directional relationship with the in-situ stress (SH) orientation pattern. Cleat orientation is found to vary laterally within same seam at the different locations, distributed from the south-east part to the north-western part of Jharia coalfield. Face cleat orientation of the 21 opencast coal mines varies from N45°E to N45°W. Change of orientation of cleat, observed around the mining areas is related the orientation of fault systems and orientation of igneous intrusions occurring within the coal bearing packet. Maximum in-situ horizontal compressive stress (SH) direction is found to be parallel to the face cleat orientation in normal faulted basin like Jharia coalfield. An overall, NNE–SSW and NW–SE orientation of the SH direction is predicted in the coal mines from cleat orientation mapping. SH orientation is locally modified at places, close to the tectonic features and igneous intrusives. Finite element stress modeling is carried out near Moonidih area. Cleat orientation predicted stress direction matches well with the finite element stress results. [Copyright &y& Elsevier]

• SHM experimental campaign conducted on a multi-arch masonry bridge located in India. • Large longitudinal crack on one of the arches detected with considerable crack width. • SHM monitored with crack growth monitoring and tilting of the spandrels. • Application of two different heavy loads (water tank and hydra crane) located in different positions. • Numerical modelling with advanced full 3D approach with adaptive NURBS FEM in limit analysis. The paper presents some SHM results belonging to a wide experimental campaign conducted on a multi-arch masonry bridge located near Mumbai (India), exhibiting a large longitudinal crack on one of the arches and the corresponding advanced numerical evaluations carried out with a NURBS kinematic limit analysis approach, used to assess the stability of the arch subjected to the passage of heavy traffic loads. The masonry bridge is a three-arch structure built during the mid-19th century by British engineers to connect Bombay with the inland of the Indian subcontinent. At present, it is characterized by a heavy state of degradation especially in one of the arches that requires an immediate evaluation of the safety under the passage of traffic loads and possible ideas of interventions to strengthen the structure, in order to avoid the propagation of deep cracks along the longitudinal direction. The adopted SHM includes the crack growth monitoring and tilting of the spandrels under the application of two different heavy loads (a water tank truck and a hydra crane) located in different positions of the arch. Numerical modelling is carried out with a full 3D approach with NURBS finite elements in limit analysis that takes into account the pre-existing crack opening and predicts with great accuracy the ultimate loads in different scenarios and the corresponding active failure mechanisms. From experimental monitoring and numerical simulations results, it is concluded that the bridge is still safe under the passage of traffic loads, but approaches the ultimate limit state for some specific configurations of the loads applied. A refurbishment is therefore needed to avoid any further propagation of the cracks up to collapse. [ABSTRACT FROM AUTHOR]