摘要：The surface conductor is the first structural casing in deepwater natural gas hydrate (NGH) development, bearing the top load while suspending the casings of various layers. NGH decomposition leads to formation settlement, changing the mechanical properties of the formation and reducing the bearing capacity of the surface conductor, threatening the safety and stability of the wellhead. Understanding the bearing characteristics of the surface conductor in the hydrate formation can guide the safe drilling operation in the field. By introducing the negative skin friction theory of pile foundations and based on conventional bearing capacity models, a method for calculating the bearing capacity of surface conductors in NGH formations was developed. Using an NGH drilling simulation apparatus, the accuracy of the bearing capacity theoretical model was verified, empirical coefficients under different conditions were obtained, and the influence of soil parameters, hydrate saturation, and decomposition temperature on the bearing capacity of surface conductors was quantified. The results indicated that compared to clay, sandy soils have higher porosity and significantly weakened strength after the decomposition of NGH; when the hydrate saturation in the formation is 20%, the reduction in bearing capacity of the surface conductor in sand exceeds 30%, and in clay soils, it decreases by 25% after complete decomposition of NGH; as the hydrate saturation increases, the reduction in the bearing capacity of surface conductors after decomposition becomes more significant. Verified through Experimentation, the error of the hydrate-bearing strata-bearing capacity model is around 10%. For short-term test production operations of NGH in water, the design depth for surface conductors is around 100 m. These research results can provide a scientific theoretical basis for the design of conductor depth below the mud锛? and reduce operational risks. 漏 2024 Elsevier Ltd

ISSN号：0029-8018

卷、期、页：卷312子辑1

发表日期：2024-11-15

期刊分区（SCI为中科院分区）：二区

收录情况：SCI（科学引文索引印刷版）,地学领域高质量科技期刊分级目录（国外T1）,EI（工程索引）,SCIE（科学引文索引网络版）

发表期刊名称：Ocean Engineering

参与作者：陈章星,Fatai Akorede, Abimbola

第一作者：付超凡,杨进,殷启帅,杨钰龙,李磊宁

论文类型：期刊论文

论文概要：付超凡,杨进,陈章星,殷启帅,杨钰龙,李磊宁,Fatai Akorede, Abimbola，Load-bearing characteristics of surface conductor in deepwater gas hydrate formations，Ocean Engineering，2024，卷312子辑1

论文题目：Load-bearing characteristics of surface conductor in deepwater gas hydrate formations