Screed

About: Screed is a research topic. Over the lifetime, 1899 publications have been published within this topic receiving 11118 citations.

A sensitivity analysis of the importance of the dynamic parameters on the paver’s performance

Abstract: In order to research the impact of the vibration on working stability of the vibration compaction system (VCS) and increase the paver’s performance, the acceleration responses at the screed surface under the excitation frequencies of the tampers and vibration screed are analyzed via the root mean square acceleration responses (RMSAR) at the bottom of the screed surface. A non-linear dynamic model of the VCS is then established to research the impact of the VCS’s dynamic parameters on the performance of paver via the objective functions of the vertical, pitch and roll RMSAR of the vibration screed. The dynamic parameters are then optimized based on a multi-objective genetic algorithm to enhance the paver’s performance. The experiment and simulation results show that the dynamic parameters greatly affect the paver’s performance. The compression performance is quickly increased, while the working stability and paving quality are reduced with increasing the angular deviations of tampers and excitation frequencies of both the tampers and vibration screed and vice versa. Also, the paver’s performance is significantly improved by using the optimal parameters of the VCS.

Combining Signal Features of Ground-Penetrating Radar to Classify Moisture Damage in Layered Building Floors

Abstract: To date, the destructive extraction and analysis of drilling cores is the main possibility to obtain depth information about damaging water ingress in building floors. The time- and cost-intensive procedure constitutes an additional burden for building insurances that already list piped water damage as their largest item. With its high sensitivity for water, a ground-penetrating radar (GPR) could provide important support to approach this problem in a non-destructive way. In this research, we study the influence of moisture damage on GPR signals at different floor constructions. For this purpose, a modular specimen with interchangeable layers is developed to vary the screed and insulation material, as well as the respective layer thickness. The obtained data set is then used to investigate suitable signal features to classify three scenarios: dry, damaged insulation, and damaged screed. It was found that analyzing statistical distributions of A-scan features inside one B-scan allows for accurate classification on unknown floor constructions. Combining the features with multivariate data analysis and machine learning was the key to achieve satisfying results. The developed method provides a basis for upcoming validations on real damage cases.

Powered roller screed with adjustable handle for wet screed attachment

Abstract: A cement screeding system in the form of a powered roller screed with a wet screed attachment The wet screed attachment includes a wet screed shoe A handle is rotationally isolated from the screed roller and is rigidly coupled to this wet screed shoe As such, motion of this handle is transmitted to the wet screed shoe in a replicating fashion

Mechanized wall plastering construction method based on metal floating screed strips

Abstract: The invention provides a mechanized wall plastering construction method based on metal floating screed strips. The mechanized wall plastering construction method includes, step 1, treating a base layer; step 2, mounting and fastening the metal floating screed strips; step 3, spraying plastering mortar layer by layer; step 4, slicking a mortar surface; step 5, taking out the floating screed strips, and filling floating screed slots with mortar; step 6, smoothening and finishing a plastering surface by an electric smoothening tool; step 7, completing construction of holes of doors and windows and external corners of wall columns at a time.