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The pore structure of the modified foam gypsum and its thermal insulation performance were revealed through the integrated study of microscopic, macroscopic, and simulation. Scanning electron microscope (SEM) was used to observe the process of coexistence of crystal and colloid embedded in the modified foam gypsum, and the relationship between the pore structure and macroscopic properties of the foam gypsum was investigated by combining with the principle of somatology, and finally, under the consideration of hierarchical aperture, the thermal conductivity of the porous material was effectively predicted by using the random distribution model of MATLAB and the finite element software of COMSOL in the joint simulation. The results showed that the symbiosis patterns between the hydration products of foam gypsum at different hydration stages were different, and the final pattern showed that the reticular C‐S‐H gel was attached to the surface of whisker‐like gypsum crystals. In the process of porosity filling of foam gypsum, three types of pore size small set phenomenon were exhibited, and the gypsum with small and uniformly distributed pore size had excellent thermal performance; MATLAB random distribution model and COMSOL finite element software joint simulation could effectively predict the thermal performance of porous materials. [ABSTRACT FROM AUTHOR]

This article presents a new, rapid technique for retrofitting reinforced concrete buildings. With the "Structural Jacketing Building Envelope Retrofit System," the entire outer shell of the building is retrofitted with steel struts that are connected to the reinforced concrete frame via dowels. The new system behaves like a composite system. As most of the seismic loads are absorbed by the new integrated external composite system, the structural elements inside the building are mainly loaded by gravity. In this way, the seismic performance and the lateral wind and torsional capacity of the retrofitted structures are increased by retrofitting the building envelope. The main advantage of this technique is the ability to retrofit existing buildings without compromising their serviceability and to quickly increase the seismic and wind capacity of buildings in regions with high seismicity and wind in the run‐up to disasters. Thus, this system is a solution for retrofitting important building structures such as hospitals, schools, energy and telecommunication buildings, and factories that cannot be retrofitted within the building. In addition to retrofitting to achieve energy efficiency in existing buildings, cladding and insulation can be easily and cost‐effectively applied to the retrofitted building envelope. Three‐dimensional models of RC buildings with and without structural building envelopes were tested under static cyclic pushover loading to simulate 3D behavior, lateral load capacity, crack patterns, and collapse mechanisms under seismic loading. The results of the tests, finite element modelling, and simulation were compared to verify the proposed system. The tests and the analysis of the models show that the structures retrofitted in the building envelope increase their seismic resistance by four times. Analytical studies for building envelope retrofit systems were also conducted and compared using different braced models. The application of this system in the retrofit of a 10‐story RC building in Istanbul is presented as a case study, including energy efficiency and architectural envelope. [ABSTRACT FROM AUTHOR]

In this work, a hybrid laminated plate is developed by changing ply orientations and stacking sequences. The hybrid laminated plate is composed of carbon nanotube reinforced composite and fiber reinforced composite layers. Negative Poisson’s ratio (NPR) is obtained for the case of [22F/(22C/−22C)3T/−22F] laminate. A theoretical laminated model considering geometric nonlinearity and shear deformation is presented. Based on a two-step perturbation method, the solutions of the motion equations are obtained to capture the nonlinear frequencies and load–deflection curves. On this basis, the fourth-order Runge–Kutta method is used to obtain the dynamic response of hybrid laminated plates. The presented model is verified by comparing the results obtained analytically and numerically. Several factors such as loading and distribution of carbon nanotubes (CNTs), and foundation type are considered in parametric study. Numerical results indicate that the thermal-mechanical behavior of hybrid laminated plates significantly improved by properly adjusting the CNT distribution. In addition, the results reveal that changes in temperature and foundation stiffness have pronounced influence on the nonlinear vibration characteristics of hybrid laminate plates with NPR as compared to those with positive Poisson’s ratio.