In engineering design, none of the existing models for calculating the contact pressure in pin-loaded lug is fully compatible with the actual working conditions. In order to obtain a more accurate formula for calculating the maximum contact pressure in pin-loaded lug, after verifying the reliability of the finite element model with PRESCALE pressure measurement film, single-parameter and multi-parameter analysis of two types of factors affecting the contact pressure distribution in the compressive surface of the pin-loaded lug were conducted in the fully elastic state. The influence of the relevant design parameters of the pin-loaded lug on its maximum contact pressure was obtained, and a formula for calculating the maximum contact pressure of the pin-loaded lug based on the Hertz stress distribution model was introduced. It is verified by a large number of finite element samples that the predicted values of the formula are in good agreement with the finite element solutions in the range of common scales for engineering design, and have high accuracy, which can be used for engineering design reference.

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In order to obtain the tensile strength of the C40 concrete accurately, the comparative study between Brazilian disc splitting experiment and the direct tensile experiment is conducted with a self-modified tensile loading device. The study shows that the tensile strength observed from the direct tensile experiments (3.64MPa) is lower than that from the experiments (5.44MPa). A comprehensive analysis of experimental results is conducted focusing on the perspectives of the specimen failure forms, energy dissipation, the correlation of strength and hydrostatic pressure etc. The study suggests that the main reasons for the differences between Brazilian tensile experimental strength and direct tensile experimental strength include the surface energy required by the specimen destruction, the bond strength between the aggregate, the hydrostatic pressure in the process of loading and other factors.

The Split Hopkinson Pressure Bar (SHPB) is used to investigate the dynamic compressive mechanical behavior of a new foamed ceramic composite under impact loading. The stress versus strain curves are obtained under high strain rates. The test results are considered to be able to assure conformability of the tests, validate the stress equilibrium assumption, and show that the stress versus strain curves of foamed ceramic composite display strain hardening effect and damage softening effect as brittle materials. Meanwhile the curve includes short plateau region while no densification region.