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Increased disposal costs and reduction in number of landfills have created a need for implementing effective waste management in the construction industry. As every construction project is unique in its way of development, benefits from the waste management may also differ from project to project and thus project characteristics should be taken into consideration when implementing the strategy. This study seeks to investigate how different project characteristics affect perception on benefits, from construction waste management, based on the survey results from 66 industry experts.

A literature review was conducted to gather information on project characteristics and its classification, construction waste management, waste management plan and its benefits. Subsequently, a set of questions was formulated to gain insight and opinion on the selection of project characteristics and particular benefits of construction waste management. A set of questions pertaining to different project characteristics linked with benefits of waste management was sent to each of the personnel for their views.

The results of this study establishes that the key materials used in projects, project size in terms of total installed costs, and project type have perceptual impacts on benefits from construction waste management.

Understanding how project characteristics will affect the benefits can help the construction industry to identify projects to which the waste management should first be applied, maximizing its benefits.

The purpose of this paper is to give a review on the newest developments of high-performance finite element methods (FEMs), and exhibit the recent contributions achieved by the authors’ group, especially showing some breakthroughs against inherent difficulties existing in the traditional FEM for a long time.

Three kinds of new FEMs are emphasized and introduced, including the hybrid stress-function element method, the hybrid displacement-function element method for Mindlin–Reissner plate and the improved unsymmetric FEM. The distinguished feature of these three methods is that they all apply the fundamental analytical solutions of elasticity expressed in different coordinates as their trial functions.

The new FEMs show advantages from both analytical and numerical approaches. All the models exhibit outstanding capacity for resisting various severe mesh distortions, and even perform well when other models cannot work. Some difficulties in the history of FEM are also broken through, such as the limitations defined by MacNeal’s theorem and the edge-effect problems of Mindlin–Reissner plate.

These contributions possess high value for solving the difficulties in engineering computations, and promote the progress of FEM.

The purpose of this paper is to implement a glass-curtain-wall cleaning robot driven by a double flexible rope, so as to replace manual cleaning. The glass-curtain-wall, because of its excellent daylighting performance, damp-proofing characteristics, heat insulation properties and aesthetics, is widely used in modern city buildings. For glass-curtain-wall buildings, regular cleaning of the glass-curtain-wall is necessary to ensure that the surface of the building appears clean and tidy, which in turn contributes toward preserving the overall aesthetic appearance of the city. Currently, the primary method of cleaning glass curtain walls is manual cleaning by workers on a suspended platform.

The mechanical structure of the proposed glass-curtain-wall cleaning robot driven by a double flexible rope is inspired by the way a spider moves by pulling its silk draglines in the air. For self-locking protection and increased rope friction, the robot’s moving section includes a worm reducer and multislot master–slave roller. The cleaning section comprises a water tank, control valve, shower nozzle and brush. The wall adsorbing section is realized by a double rotor. The workspace of the robot is analyzed. Flexible rope winding and unreeling control of the cleaning robot is deduced. The force of the cleaning robot when the double rotor is working is analyzed and calculated. The prototype of the glass-curtain-wall cleaning robot model driven by a double flexible rope is established, and experiments wherein the robot moves along a preset track, as well as cleaning experiments, are performed.

The prototype of the glass-curtain-wall cleaning robot model driven by a double flexible rope can move along the preset track, satisfy the design functions and clean effectively. The experimental results verify the validity and practicality of the robot.

The implication of this research is that a glass-curtain-wall cleaning robot model driven by a double flexible rope fulfills the movement strategy and drive-type requirements for cleaning glass curtain walls. The limitation of this research is that it is difficult to implement rapid cleaning.

The traditional method of manual cleaning by workers on a suspended platform will be changed after the glass-curtain-wall cleaning robot is manufactured, and the advent of this cleaning robot for the low- and mid-rise buildings will reduce the cost of cleaning buildings, improve the working environment and enhance production efficiency.