http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
- 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
- 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
RISS 인기검색어
- 검색키워드
- 저자 : Xudong Kang (검색결과 3 건)
- 무료
- 기관 내 무료
- 유료
-
Seismic Bearing Capacity of Stirp Footings with Modified Pseudo-dynamic Method
Xudong Kang,Jianqun Zhu,Lili Liu 대한토목학회 2024 KSCE Journal of Civil Engineering Vol.28 No.5
Current research has shown a nonlinear trend in the failure of soil, and the single tangent method is commonly adopted when coping with nonlinear problems of soil failure. However, the method equates a nonlinear criterion to an optimizable linear criterion, which may differ from the actual situation, resulting in conservative results. In this paper, two types of piece-wise log-spiral failure mechanisms for bearing capacity estimations, including symmetrical and unilateral mechanisms were proposed with the nonlinear Mohr-Coulomb criterion. The static bearing capacity of foundations was evaluated using the symmetric failure mechanism, while the seismic bearing capacity of foundations was evaluated adopting a modified pseudo-dynamic method based on the unilateral failure mechanism. The result shows that the bearing capacity calculated in the paper is smaller compared to the result using the linear Mohr-Coulomb criterion. For London clay, the static bearing capacity is reduced by about 45% at a foundation width equal to 1m. From the comparisons, it is found that the proposed approach of piece-wise log-spiral failure mechanism for bearing capacity estimation is effective. In addition, parametric studies show that the nonlinear parameters, the initial factor of seismic acceleration, the normalized frequency, and the damping ratio all have obvious effects on the seismic bearing capacity. A significant reduction in the seismic bearing capacity of the foundation occurs when the normalized frequency sH/Vs is equal to (0.5 + n) (n = 0, 1, 2, …). Considering that the approach proposed provides a strict upper bound to the bearing capacity, the result imparts confidence in the approach of analysis presented.
-
Xiaoyun Li,Zhen Wang,Xin Jing,Xudong Li,Junwei Wang,Mao-qing Kang,Yuhua Zhao,Qifeng Li 한국공업화학회 2022 Journal of Industrial and Engineering Chemistry Vol.107 No.-
Hydrogen bonds, which can be divided into many types along with the deepening of research, exist inmany compounds and have certain impact on properties of substances. In this work, effect of intramolecularhydrogen bond on solvent resistance of polymeric membranes was studied from two aspects. On theone hand, the existence of intramolecular hydrogen bond on solvent resistance of polymeric membraneswas studied by constructing and shielding special hydroxyl groups in typical polymer polyurethane. Onthe other hand, content of intramolecular hydrogen bond on solvent resistance was investigated by buildingdifferent ratios of inter- and intra-molecular hydrogen bonds in polyvinyl alcohols. The structures,solvent resistance and hydrogen bonding interactions were systematically investigated by FT-IR, XRD,Ds and performances before and after immersed in solvents. Permeabilities of the membranes for practicalapplication were also characterized. The results showed that distinct type and ratio of hydrogenbonds played different role on solvent resistance. A good agreement between the swelling performancesand content of intramolecular hydrogen bond proved the positive effect of intramolecular hydrogen bondon solvent durability of polymeric membranes. In addition, polyurethane membranes exhibited goodimpermeability to water vapor, oxygen and chloride ions which showed potential application in manyfields.
-
Bin Liu,Wei Fan,Xu Huang,Xudong Shao,Lijing Kang 한국콘크리트학회 2020 International Journal of Concrete Structures and M Vol.14 No.4
Detailed finite element (FE) models are often employed to predict the impact responses of reinforced concrete (RC) columns. However, they always require substantial investments of time and effort in modeling and analysis so that they are not widely used in practice, particularly in preliminary designs. Moreover, although some simplified models have been established for beams and slabs under impact loading, few attempts have been made on modeling RC columns. For these reasons, this paper proposes a simplified modeling method to accurately capture the impact-induced response and damage of circular RC columns. In the proposed method, a two-degree-of-freedom (DOF) system was used to describe the interaction between the impactor and the impacted column. The formulas, and procedure to estimate the force-deformation relationship with strain-rate effects were presented according to the section-based analysis. The influence of the unloading stiffness on the residual deformation was addressed, and the method to determine the unloading stiffness of circular columns was proposed. Furthermore, a fiber-based beam-column element modeling method was developed to estimate the force-deformation relationship of the columns with strain-rate effects. The proposed simplified method was demonstrated by the drop-hammer impact tests to be capable of predicting the impact response of RC columns well. Its accuracy in the residual deformation is superior to that of the detailed FE simulation. Parametric studies were performed to investigate the damage characteristics of axially-loaded circular RC columns under various impact scenarios.
연관 검색어 추천
이 검색어로 많이 본 자료
활용도 높은 자료
