Research Article
Research on Calculation Method of Bottom Isolation Shear Wall Structure Considering Fuzzy Analytic Hierarchy Rrocess
Li Yulou,
Jie Yulin*,
Chen Lu,
Yu Zhaohong
Issue:
Volume 12, Issue 1, February 2024
Pages:
1-7
Received:
27 December 2023
Accepted:
9 January 2024
Published:
18 January 2024
Abstract: In our country, buildings are facing the severe threat of earthquake disaster, almost all buildings have to carry out structural seismic design. Shear wall structure is one of the common structural systems of high-rise building, in order to study the isolation effect of high aspect ratio structure and understand the reason of isolation effect, under the action of horizontal force, Timushenko beam can assume the deformation mode of bending-shear type, which is close to the deformation characteristics of shear wall structure. The bottom isolation shear wall structure has the characteristics of bending-shear lateral displacement curve under the action of strong earthquake, and its mechanical characteristics are similar to Timoshenko beams. How to accurately evaluate the importance and reliability of many influencing factors, this paper adopts the fuzzy analytic hierarchy process to analyze the dynamic characteristics before and after the seismic isolation of the cantilever Timoshenko beam of the bending-shear structure, determine the weight of each evaluation item for the analysis of the damping effect of the whole structure. It is concluded that prolonging the period, reducing the participation mass coefficient of high-order mode shapes and increasing the damping ratio of the system are the three major factors for vibration isolation technology.
Abstract: In our country, buildings are facing the severe threat of earthquake disaster, almost all buildings have to carry out structural seismic design. Shear wall structure is one of the common structural systems of high-rise building, in order to study the isolation effect of high aspect ratio structure and understand the reason of isolation effect, unde...
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Research Article
Analysis on Vertical Variation Characteristics of Eogene Formation Water in Jizhong Depression
Zhou Qingyuan*,
Yang Chunhua,
Yu Zhicheng,
Zhang Yi
Issue:
Volume 12, Issue 1, February 2024
Pages:
8-13
Received:
30 January 2024
Accepted:
6 March 2024
Published:
13 March 2024
Abstract: Jizhong Depression is located in the middle and west of Bohai Basin. During the Tertiary period, the depression was in a relatively stable state, and the shape of the depression did not change much, but the internal ups and downs of the depression were still continuous. In the Tertiary period, it experienced three development stages: early division, middle communication and late contraction, and three different sedimentary facies appeared accordingly. At the same time, it also caused three shifts of sedimentary centers. In the medium-term communication stage, two large water invasion periods occurred, and in some areas, the sedimentary water medium changed from salty to light twice. Oil and gas in the depression are associated with formation water, and the formation history of formation water is closely related to the formation history of oil and gas reservoirs. They are both in a hydrodynamic system and exchange material components for a long time. The lower tertiary is the main oil-bearing interval in central Hebei, but it is affected by the late tectonic movement and its structural characteristics are complex. Therefore, the hydrochemistry and vertical distribution characteristics of tertiary strata are studied. By effectively studying the distribution characteristics of formation water, it is concluded that the salinity of formation water in the basin tends to increase from edge to center and from shallow to deep, mainly in alternate blocking zones and alternate stagnation zones. The water deposition environment is relatively stable and the general regularity is obvious, which is an effective means to study the migration and distribution of oil and gas.
Abstract: Jizhong Depression is located in the middle and west of Bohai Basin. During the Tertiary period, the depression was in a relatively stable state, and the shape of the depression did not change much, but the internal ups and downs of the depression were still continuous. In the Tertiary period, it experienced three development stages: early division...
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Research Article
Analysis of the Production Characteristics of Heterogeneous Reservoirs Assisted by Shallow Gas by Depressurization Path
Zifei Wang,
Kangji Shi,
Peng Gao,
Lei Yang*
,
Yongchen Song
Issue:
Volume 12, Issue 1, February 2024
Pages:
14-19
Received:
10 March 2024
Accepted:
29 March 2024
Published:
12 April 2024
Abstract: The problems of low gas production rate and low gas production restrict the commercial production of natural gas hydrate. The combined production of hydrate reservoirs and underlying shallow gas reservoirs is expected to make up for this shortcoming. Most natural gas hydrates in the formation exhibit vertical heterogeneous distribution characteristics; There is still little research on the mechanism of its impact on the characteristics of co harvesting. This work focuses on the interaction between vertical heterogeneous hydrate reservoirs and shallow gas layers, and analyzes the mechanism of the impact of depressurization pathway on the characteristics of combined production. The results indicate that before the pressure in the shallow gas layer is equal to the pressure in the hydrate layer, the change in pressure reduction method cannot significantly affect the characteristics of pressure changes in the shallow gas layer; In addition, there is a significant hysteresis effect in the pressure evolution of shallow gas layers compared to hydrate layers. Not limited to this, the presence of shallow gas layers will also weaken the impact of pressure reduction paths on the gas production characteristics of combined production, which makes the gas production characteristics at this time more inclined towards the gas production characteristics under direct pressure reduction. In summary, in order to effectively increase the temperature of shallow gas and enhance hydrate decomposition, it is necessary to flexibly adjust the pressure reduction indicators of the pressure reduction path in different mining stages. The results can lay the foundation for clarifying the mechanism of interlayer interference in multiple gas source reservoirs.
Abstract: The problems of low gas production rate and low gas production restrict the commercial production of natural gas hydrate. The combined production of hydrate reservoirs and underlying shallow gas reservoirs is expected to make up for this shortcoming. Most natural gas hydrates in the formation exhibit vertical heterogeneous distribution characterist...
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