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 : Ronggui Deng (검색결과 3 건)
- 무료
- 기관 내 무료
- 유료
-
Jin Zhang,Ronggui Deng,Zhibin Zhong,Peipei Wu,Shaoli Qi 대한토목학회 2023 KSCE Journal of Civil Engineering Vol.27 No.10
In high in-situ stress zones, cataclastic rocks have exerted a significant influence on the stability of engineering structures. However, the mechanical properties of cataclastic rocks can not be accurately studied due to difficulties in sampling and laboratory testing. In this paper, laterally confined compression tests for specimens that were obtained by the developed in-situ sampling devices were performed to investigate the stress states. A modified thick-walled cylinder model considering axial shear stress was introduced. The interaction mechanics model for a compressed sample and an equivalent single-layer cylinder was established. Based on the principle of elasticity, the laterally confined stress, the axial shear stress, and the axial stress of the sample were derived and obtained. Moreover, the effects of mechanical and geometric parameters of the equivalent cylinder on the force condition of the specimen were analyzed. The results show that the confined stress is positively correlated with the equivalent elastic modulus and the geometric factor. Therefore, the confined stress can be strengthened by increasing the elastic modulus, alternatively, increasing the outer diameter and decreasing the inner diameter. However, the axial stress is little affected by the equivalent elastic modulus and the geometric factor and is not affected by the equivalent Poisson's ratio. As the distance from the center height increases, the axial stress decreases linearly and the difference in axial stress becomes larger considering axial shear stress and ignoring axial shear stress.
-
Yuanyuan Wang,Ronggui Deng,Tao Guo,Yi Sun,Bo Huang,Qinke Wang 대한토목학회 2023 KSCE Journal of Civil Engineering Vol.27 No.3
More and more rigid frame bridges with high piers and large spans are built in the high and steep slope areas of deep valleys in southwest China. The slow deformation of the slope in the geological sense often causes the problems of piles, which in turn causes damage of the upper bridges. The vertical bearing characteristics of bridge piles in slope still need to be conducted because of the peculiarity of slope topography. The vertical deformation and bearing characteristics of piles in the slope area were experimentally studied by considering different influencing factors and the fitting formula for the ultimate bearing capacity of the piles under vertical load is obtained. The results show that the vertical deformation and ultimate bearing capacity (defined by vertical limit settlement deformation of 0.013 times the pile diameter) of the pile are closely related to its position in the slope. The pile in the middle of the slope has the lowest vertical ultimate bearing capacity. Moreover, the side frictional resistance transfer depth of the pile in continuous slope is greater than that of the pile in unilateral slope. Additionally, the slope angle has a significant influence on the vertical bearing performance of piles. The delayed settlement of the pile top decreases approximately 40% at most and the vertical ultimate bearing capacity of the pile increases 48.6% at most as the slope angle decreases by 15°. Meanwhile, the side friction resistance of the pile increases with the decrease of slope angle. The bending moment applied to the pile top reduces the vertical ultimate bearing capacity of the pile and increases the axial force of the pile body. The results can provide data support for pile design and instability judgment with similar geological conditions.
-
Stability Analysis of 3D Tunnel Face of Shallow Rectangular Shield Tunnel
Wenpo Wang,Ronggui Deng,Hongfeng Liu 대한토목학회 2023 KSCE Journal of Civil Engineering Vol.27 No.3
In recent years, an increasing number of rectangular excavation sections have appeared in pipe-jacking shield tunnel projects. In previous studies, calculating the stability of a tunnel face in a noncircular shield tunnel usually required a circular section. It is carried out according to the principle of equivalent areas. Although this method makes it easy to calculate the stability, deviation still occurs. To solve this issue, the rectangular shield tunnel is used as the research object. Spatial discretization technology is used to extend the rotational failure mechanism of 3D rigid blocks to the tunnel face of rectangular tunnels. Moreover, it is accomplished under the theoretical background of the upper bound method. The MATLAB calculation results were compared with FLAC3D, and the process proved to have sufficient accuracy and a high efficiency. Then, the influences of the failure modes and limit support pressure by dimensionless parameters are studied. The results show that the parameters that have a great impact on the failure region and stability of the tunnel face are H/D, C/D, and the internal friction angle ϕ, and the parameters that have little influence on them are σs/c and γD/c. Finally, a dimensionlessparameter design chart that has a limit support pressure with a rectangular tunnel and a single homogeneous frictional soil layer is drawn and fitted using a ternary quadratic polynomial. Furthermore, it can be used for preliminary design.
연관 검색어 추천
이 검색어로 많이 본 자료
활용도 높은 자료
