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Reference the test method of the rock mechanical properties, through the concrete Brazilian and flattened Brazilian disc specimen under quasi static diametral compression tests and compared, research shows that flattened Brazilian disc specimens split eventually destroy the formation more than one cracks, on both sides along the platform has large cracks, even cracks in some specimens from the platform to the next platform throughout the ipsilateral endpoint, and complete Brazilian disc does not appear this phenomenon. Complete Brazilian disc specimens and flattened Brazilian disc test specimen loading force curves form remains the same, but flattened Brazilian disc specimens eventually reach the extreme loading force has a higher value than the first extreme loading force.

Induction heat-bended pipes used in oil and gas pipelines are commonly manufactured by heating-bending techniques, and ductile fractures related to large deformation easily occur in the heating-bending manufacturing process. This study investigated the ductile damage behavior and modeling of X100 pipeline steel to reveal the evolution of ductile damage fracture of high-strength pipeline steel at high temperatures. Three methods, namely, Gleeble tensile, separation Hopkinson pressure bar (SHPB), and MTS quasi-static notch tensile tests, were performed at room and high temperatures for the analysis of the characteristics of flow stress and failure strain of X100 pipeline steel. The Johnson-Cook model was used for the establishment of the damage constitutive model of X100 pipeline steel, and its accuracy and reliability were verified by experimental data. Results show that strain rate enhancement and high-temperature softening effect are significant. The failure strain of X100 pipeline steel is positively correlated with temperature and negatively correlated with stress triaxiality and strain rate. The established constitutive model can accurately describe the high-temperature plastic deformation and damage evolution behavior of X100 pipeline steel. This study provides a foundation for the prediction of damage and failure in heating-bending process.

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Different soluble inorganic salts were irrigated into batches of soil samples by setting contrastive experiments on the basis of Tessier sequential extraction procedure to study their influences upon Cd forms in the soil. Research shows that all the three salts were able to influence the forms of Cd in the soil: NaCl and Na2SO4added into the soil could increase the contents of exchangeable Cd and the higher the concentration, the greater the impact, while Na2CO3could decrease it by 30.35%(4 g/kg Na2CO3added) and 69.87%(8 g/kg Na2CO3 added). Carbonate content of Cd was influenced obviously by NaCl, with the decrease of 7.30%, 10.52% corresponding to low concentration and high concentration of NaCl, and Na2CO3can increase this form slightly, Na2SO4had little effect, so the content remained unchanged. The Fe-Mn oxidation form of Cd remained the original level when NaCl was added in the samples while it increased with the addition of Na2CO3obviously and the concentration increased 8.67% (4 g/kg Na2CO3added) and 51.85% (8 g/kg Na2CO3added),but it decreased by the effect of Na2SO4. Organic Cd and the residual Cd fluctuated slightly at a very low concentration. The total Cd decreased with the addition of sodium salt.