Description
Ahmad Azhar bin Azizan
Department of Survey and Mapping Malaysia
JUPEM Kedah
Kata kunci: Terrestrial Laser Scanner, Conventional Method, Strata Survey, Strata As-built Plan, Data Comparison
ABSTRAK
The construction of high buildings in urban areas has significantly increased recently. Consequently, strata surveying tasks are conducted in line with this development. Traditional methods such as distometer and measuring tape have been proven to be less accurate and at the same time, require extensive documentation for review observations. Additionally, the backlog of reviews for each application submitted to the survey and mapping department of Malaysia, Jupem has resulted in a slow and inconsistent review process. However, lidar technology, particularly terrestrial laser scanning (TLS) and mobile laser scanning (MLS), will have a significant impact on strata measurement with their advantages
in efficient and accurate measurement, efficient data storage such as building information management, non-contact measurement technology for objects, and effective 3-D data visualisation. This study aims to prove that a TLS tool is high accuracy, time saving and more efficient. The study encompasses stages involved in TLS, including pre-research and planning, data acquisition, data processing, and generating 3-D point cloud and data analysis. After the data was captured, the data were processed by using the magnet collages and autodesk Revit software. The Revit generated the 3-D point clouds into a 2-D plan. Data assessment involves evaluating accuracy by comparing TLS measurements with a distometer for each strata parcel dimension and calculating the comparative differences using the RMSE formula. The use of the RMSE formula is to determine the accuracy of the TLS data captured in the field. The final outcome is to generate the as-built strata plan and aim to achieve checking dimension distances within a tolerance threshold of 0.1 metres based on the circular kpup-1-2015-jilid-i-v2016 provided by Jupem. After comparison, it is determined the lowest and highest values are +/- 0.01 metres and +/- 0.091 metres. RMSE is determined the lowest and highest values are 0.004 metres and 0.053 metres. This indicates that the RMSE data does not exceed > 0.1 metres, staying within the provided tolerance. The TLS method holds significant potential in strata measurement tasks, particularly in verifying the dimensions of strata parcels by Jupem officers, and it can generate strata as-built plans with better accuracy compared to conventional methods. The point cloud data can be utilised for documentation support and data reusability, making it highly suitable for future strata title surveys.