Use of 3D laser scanning for flatness and volumetric analysis of mortar in facades

Abstract

The ongoing process of industrialization of construction sites encourages the use of new building systems that conflict with traditional techniques associated with the risks of incompatibilities and continuance of control fixed ideas with a significant variability. A practical example is the cement mortar for plastering, commonly used as a corrective factor for facade flatness failures caused by the inaccuracy of the plumb line, rudimentary method used in geometric control of concrete structures and facade of mapping during the execution of the work, favoring the accumulation of errors that reflect the mortar thickness, increasing consumption, losses and defects. Alternatively for improvement, this study analyzed through a case study, the innovative application of 3D laser scanning technology consolidated on the facade of a building to map the surface flatness of the façade and, in an unprecedented manner, to quantify the volume of mortar. The results showed the feasibility of the technique as a solution to accurately identify the critical areas of the facade on the peripheral concrete structure and masonry and calculate, based on the volumes, the financial impact associated with mortar overthicknesses in critical areas compared with the reductions thickness after treatment of these areas.

Surface Waviness Evaluation of Two Different Types of Material of a Multi-Purpose Hall Using Terrestrial Laser Scanner (TLS)

“…Fuchs et al [20] and Shafer and Weber [21] developed deformation monitoring methods to discover the differences in positions of TLS data points concerning a reference surface when processing TLS data for QC. In [22], a colour map generated from TLS data was used to analyse the flatness of multi-story building facades. Tang et al [23] devised three techniques for determining the difference in elevation of points in a point cloud concerning a plane derived from a Building Information Modelling (BIM) model or a user-specified plane.…”

A Comparison of TLS-based and ALS-based Techniques for Concrete Floor Waviness Assessment

“…The acquired data is processed with the help of a multitude of algorithms, based on the desired applications. Few of the applications include assessing the flatness of the exterior facades using a color map derived from TLS point clouds [35], visualizing the elevation differences across a floor using elevation map generated from point cloud data [36] and assessing the dimensional compliance of concrete elements using BIM and TLS-based point cloud data [37]. Lidar-based point clouds, with the application of the Continuous Wavelet Transform (CWT), were also used in the assessment of floor waviness in [3,4].…”