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Purpose This paper is to present an experiment to verify that the motion errors of robust topology optimization results of compliant mechanisms are insensitive to load dispersion. Design/methodology/approach First, the test pieces of deterministic optimization and robust optimization results are manufactured by the combination of three-dimensional (3D) printing and casting techniques. To measure the displacement of the test piece of compliant mechanism, a displacement measurement method based on the image recognition technique is proposed in this paper. Findings According to the experimental data analysis, the robust topology optimization results of compliant mechanisms are less sensitive to uncertainties, comparing with the deterministic optimization results. Originality/value An experiment is presented to verify the effectiveness of robust topology optimization for compliant mechanisms. The test pieces of deterministic optimization and robust optimization results are manufactured by the combination of 3D printing and casting techniques. By comparing the experimental data, it is found that the motion errors of robust topology optimization results of compliant mechanisms are insensitive to load dispersion.

Salinization has an important impact on the degradation of ancient masonry buildings, and systematically mastering the law of salt migration and degradation of ancient masonry buildings is an important part of the protection of ancient buildings. In this paper, the damage law of gray bricks under the action of salt crystallization is studied. The orthogonal test method is used to carry out cyclic degradation tests on gray bricks. The nominal strength is proposed as a mechanical parameter to measure the structural damage of grey bricks, and the change in compressive strength and crystallization pressure of the samples after the test is measured and analyzed. The results show that the damage of different salts in the gray bricks shows a certain difference. Magnesium sulfate and sodium chloride cause significant damage to the surface of the gray bricks, while calcium chloride does not cause significant damage to the surface of the gray bricks. When the concentrations of sodium chloride solution, calcium chloride solution and magnesium sulfate solution are less than 13.73 mol/L, 11.47 mol/L and 17 mol/L, respectively, the nominal strength of gray brick samples increases; In the range of 9.9 mol/L and 4.73–8.94 mol/L, the crystallization pressure began to appear inside the sample. The research results provide an important scientific basis for evaluating the damage caused by salting to the damage of porous ancient building materials such as masonry.