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 : Songhe Wang (검색결과 5 건)
- 무료
- 기관 내 무료
- 유료
-
A novel modeling of settlement of foundations in permafrost regions
Wang, Songhe,Qi, Jilin,Yu, Fan,Liu, Fengyin Techno-Press 2016 Geomechanics & engineering Vol.10 No.2
Settlement of foundations in permafrost regions primarily results from three physical and mechanical processes such as thaw consolidation of permafrost layer, creep of warm frozen soils and the additional deformation of seasonal active layer induced by freeze-thaw cycling. This paper firstly establishes theoretical models for the three sources of settlement including a statistical damage model for soils which experience cyclic freeze-thaw, a large strain thaw consolidation theory incorporating a modified Richards' equation and a Drucker-Prager yield criterion, as well as a simple rheological element based creep model for frozen soils. A novel numerical method was proposed for live computation of thaw consolidation, creep and freeze-thaw cycling in corresponding domains which vary with heat budget in frozen ground. It was then numerically implemented in the FISH language on the FLAC platform and verified by freeze-thaw tests on sandy clay. Results indicate that the calculated results agree well with the measured data. Finally a model test carried out on a half embankment in laboratory was modeled.
-
Shear Strength Behavior of Coarse-Grained Saline Soils after Freeze-Thaw
Songhe Wang,Jiulong Ding,Jian Xu,Jianwei Ren,Yugui Yang 대한토목학회 2019 KSCE JOURNAL OF CIVIL ENGINEERING Vol.23 No.6
The bearing capacity of embankment filled by coarse-grained saline soils will be deteriorated after freeze-thaw, especially when shallow groundwater is included. Direct shear tests were carried out on coarse saline specimens that experienced freeze-thaw cycling. The shear strength of soil specimens at three densities strongly depends upon the normal stress when freeze-thaw is not involved, manifesting as a linear increase. Strength indexes such as cohesion and internal friction angle grow at higher dry densities while little change noted in the residual. The cohesion increases with salt content but lowers with freeze-thaw, especially in initial five cycles, beyond which it stabilizes. The internal friction angle is not associated with the above two factors. The stress-strain curves after freeze-thaw are all strain softening, especially at higher densities. The shear stress exhibits larger influence on particle crushing than freeze-thaw. The modified relative breakage index was calculated based on particle grading curves, and is negatively correlated with the cohesion. An empirical equation was proposed by fitting test data incorporating both salt content and freeze-thaw cycles. Comparisons prove that the calculated cohesion agrees well with the measured data.
-
Experimental study on freezing point of saline soft clay after freeze-thaw cycling
Wang, Songhe,Wang, Qinze,Qi, Jilin,Liu, Fengyin Techno-Press 2018 Geomechanics & engineering Vol.15 No.4
The brine leakage is a tough problem in artificial freezing engineering. This paper takes the common soft clay in Wujiang District as the study object, and calcium chloride solutions with six salinity levels were considered. The 'classic' cooling curve method was employed to measure the freezing point of specimens after freeze-thaw. Results indicate that four characteristic stages can be observed including supercooling, abrupt transition, equilibrium and continual freezing, strongly dependent on the variation of unfrozen water content. Two characteristic points were found from the cooling curves, i.e., freezing point and initial crystallization temperature. A critical value for the former exists at which the increment lowers. The higher the saline content approximately linearly, lower the freezing point. In the initial five cycles, the freezing point increases and then stabilizes. Besides, the degree of supercooling was calculated and its correlations with water, salt and freeze-thaw cycles were noted. Finally, an empirical equation was proposed for the relationship of freezing point and three main factors, i.e., water content, saline content and freeze-thaw cycles. Comparison of calculated and measured data proves that it is reliable and may provide guidance for the design and numerical analysis in frozen soil engineering.
-
Jian Xu,Liyang Zhou,Ke Hu,Yanfeng Li,Xiangang Zhou,Songhe Wang 대한토목학회 2022 KSCE JOURNAL OF CIVIL ENGINEERING Vol.26 No.5
In this study, the influence of wet-dry cycles on the uniaxial compression behavior of fissured loess after vibration was investigated by small shaking table tests, wet-dry tests, and uniaxial compression tests. Results show that the initial elastic modulus and peak strength both decline after wet-dry cycles while the morphology of stress-strain curves shows insignificant changes. Except for samples with a fissure angle α = 45°, where the bimodal stress-strain curves were observed, all show softening trend. The failure mode can be classified into four main types: fracture failure (α = 0° and 15°), slip-fracture coupled failure (α = 45°), slip failure (α = 60°), and compression shear failure (α = 30° and 90°). The failure modes of samples at α = 0°, 15°, 45°, and 60° are independent of wet-dry cycles but strongly depend on fissure angle, while those at the other fissure angles are more susceptible to wet-dry cycles. The uniaxial compressive strength (UCS) of fissured loess samples before vibration are greater than those after vibration. The relationship between UCS and fissure angle before and after vibration show double-valley pattern. A binary medium model for fissured loess considering vibration and wet-dry cycles was constructed, which was verified by test data.
-
Triaxial Shear Behavior of Basalt Fiber-Reinforced Loess Based on Digital Image Technology
Jian Xu,Zhipeng Wu,Hui Chen,Longtan Shao,Xiangang Zhou,Songhe Wang 대한토목학회 2021 KSCE Journal of Civil Engineering Vol.25 No.10
Engineering construction in loess areas often requires improvement of loess. Basalt fiber-reinforced soil due to complexity of material composition often exhibits poorly predictable mechanical behavior. In this study, digital image technology-based unconsolidated-undrained (UU) triaxial shear tests were carried out on loess samples at three fiber lengths (L) and four fiber contents (η). Results prove the improvement of the shear strength of loess by basalt fiber inclusion, which varies in inverted u-shaped pattern with fiber length or fiber content, with the maximum at η = 0.6%, L = 12 mm. Digital Image Technology was employed to analyze the damage characteristics and strain field of the surface of the sample at different loading time. The volumetric strain of the reinforced sample decreases at higher fiber content or fiber length, from shear contraction to dilatancy. The unreinforced sample exhibits a typical brittle failure mode with visible shear band, while plastic failure for reinforced samples with an overall bulging failure mode. A statistical damage constitutive model of fiber-reinforced loess was established with limited parameters calibrated. The rationality of the model was verified by comparisons of measured and calculated stress-strain data.
연관 검색어 추천
이 검색어로 많이 본 자료
활용도 높은 자료
