Study on the Axial Compressive Behavior and Constitutive Relationship of Lightweight Mixed Ceramic Concrete.

To thoroughly study the stress-strain relationship of lightweight mixed ceramic concrete, this paper conducts axial compressive strength tests on three groups of lightweight mixed ceramic concrete specimens with different types and contents as the basis. It establishes the elastic modulus calculation formula and compressive stress-strain formula for lightweight mixed ceramic concrete by combining with the current standards and related research. The results show that lightweight mixed ceramic concrete, made of a mixture of different types and densities of ceramic grains, has better mechanical properties and deformation properties.

The 3D lightweight structural characteristics of the beetle forewing.

The present paper renewedly expounds upon the characteristics of the 3D lightweight structure of beetle forewings and notes that two biomimetic structures (models) that have appeared in recent years do not comply with these characteristics based on a comparison of the structures of the biological prototypes. The first model features transverse tubules based on observations of circular holes in cross-sectional figures of the Cybister forewing. The second is a biomimetic spherical cavity model with hollow trabeculae that reportedly exhibits superior mechanical properties because its structures are most similar to the biological prototype.

Non-hollow-core Cybister trabeculae and compressive properties of two biomimetic models of beetle forewings.

In 2006, the forewing trabeculae of Cybister tripunctatus Olivier (i.e., Cybister) beetles were reported to be hollow, and a biomimetic structural model (i.

Compressive failure modes and parameter optimization of the trabecular structure of biomimetic fully integrated honeycomb plates.

To develop lightweight biomimetic composite structures, the compressive failure and mechanical properties of fully integrated honeycomb plates were investigated experimentally and through the finite element method. The results indicated that: fracturing of the fully integrated honeycomb plates primarily occurred in the core layer, including the sealing edge structure. The morphological failures can be classified into two types, namely dislocations and compactions, and were caused primarily by the stress concentrations at the interfaces between the core layer and the upper and lower laminations and secondarily by the disordered short-fiber distribution in the material; although the fully integrated honeycomb plates manufactured in this experiment were imperfect, their mass-specific compressive strength was superior to that of similar biomimetic samples.

Characteristics of the tensile mechanical properties of fresh and dry forewings of beetles.

Based on a tensile experiment and observations by scanning electron microscopy (SEM), this study demonstrated the characteristics of the tensile mechanical properties of the fresh and dry forewings of two types of beetles. The results revealed obvious differences in the tensile fracture morphologies and characteristics of the tensile mechanical properties of fresh and dry forewings of Cybister tripunctatus Olivier and Allomyrina dichotoma. For fresh forewings of these two types of beetles, a viscous, flow-like, polymer matrix plastic deformation was observed on the fracture surfaces, with soft morphologies and many fibers being pulled out, whereas on the dry forewings, the tensile fracture surfaces were straightforward, and there were no features resembling those found on the fresh forewings.

Review of beetle forewing structures and their biomimetic applications in China: (II) On the three-dimensional structure, modeling and imitation.

This paper reviews the research progress made in China regarding the microstructure of the forewing trabeculae, their anti-peeling and anti-collisional mechanical properties, the three-dimensional (3D) microstructures of the forewings, their modeling, and their mechanical properties. We focus on 1) the distribution of the trabeculae in two types of beetles with a six-fold difference in density, the structure of the trabeculae and a proposed 3D model with an integrated trabeculae-honeycomb structure; 2) finite element analyses and experimental results showing that the average anti-peeling strength in the presence of trabeculae can be as much as approximately three-fold greater than that in the absence of trabeculae; 3) the strengthening mechanisms of these structures and describe an optimized double thin-walled biomimetic structure that possesses excellent absorption and buffering properties; 4) the development of technologies to produce fully integrated honeycomb plates with short fibers as a reinforced composite material and the verification that these plates are strong and lightweight and exhibit good integrity. Finally, we note the shortcomings in China in this field of research and propose possible future research directions in the field of biomimetic functional materials.