Physical characteristics of boulders formed in the tropically weathered granite

Deep weathering profile is a common phenomenon for humid tropic especially in Malaysia. The reactions of deep weathering under soil surface are decomposition of the massive rock and formation of thick stratum of soil and boulders. However, the occurrence of embedded boulders or loose blocks in the highly to completely weathered in the hilly area is not fully understood and investigated. This paper investigates the occurrence and physical characteristics of boulders in the granitic area. The parameters investigated are boulder’s discoloration, size, shape, rindlet properties and their distribution. Colour and shape were determined based on rock colour chart by Krumbein and Croft’s chart respectively. Size, rindlet and its distribution were determined based on field observation. Field results revealed that boulders in the hilly area can be found as shallow as 2 m from ground surface. In addition, it is found that boulder that embedded in deeper zone became larger in size and surrounded by thicker rindlet of up to 50 cm thick. Boulders embedded in soil stratum at weathering zone 4 and 5 are mostly independent and scattered around the weathering profile. The boulders can also be presented in various shapes; the smaller boulder is located at the upper zone more to flat to very spherical shape and rounded to well rounded edges, while the larger boulder that is located at lower zone more to sub-spherical shape and well rounded edges

Building inventory for seismic risk assessment using unmanned aerial vehicle

The concept of applying Unmanned Aerial Vehicles (UAVs) with proper cameras in acquiring imagery data had been implied for many research and industry purposes in the recent years. This paper shows that the concept of using UAV and camera as a method of data collection of building inventory for seismic risk assessment. It is a part of the method of Rapid Visual Screening (RVS) survey in order to obtain the building inventory that includes the dimensions of building. The UAV used for this project is a high technology hexacopter that flies autonomously in order to obtain a constant data. The camera in the other hand is a high resolution digital compact camera with a Global Positioning System (GPS) built-in the camera for a more precise and accurate data collection of aerial images. The images then will be properly altered which the data acquisition will be used for analysis in a computer software. The case study for this research are buildings in the area of Universiti Teknologi Malaysia (UTM), Johor. The flexibility, safety, eases of operation, and relatively low-cost of ownership and operation make possible of UAVs and digital compact camera to be implemented in data collection of building inventory for seismic risk assessment