Open Access

ARTICLE

An Experimental Study on the Reinforcement of Weakly-Consolidated Shallow Formation in Deep Water Using an Epoxy Resin-Based Fluid

Leiju Tian¹, Yuhuan Bu^1,*, Huajie Liu^1,*, Lingyun Zhao^2,3

1 School of Petroleum Engineering, China University of Petroleum (East China), Qingdao, 266555, China
2 Key Laboratory of Unconventional Natural Gas Evaluation and Development in Complex Tectonic Areas, Ministry of Natural Resources, Guiyang, 550000, China
3 Guizhou Engineering Research Institute of Oil & Gas Exploration and Development, Guiyang, 550000, China

* Corresponding Authors: Yuhuan Bu. Email: ; Huajie Liu. Email:

Fluid Dynamics & Materials Processing 2023, 19(5), 1215-1226. https://doi.org/10.32604/fdmp.2022.022219

Received 27 February 2022; Accepted 23 May 2022; Issue published 30 November 2022

Abstract

The mechanical properties of Portland cement differ from the weakly consolidated shallow formation in deep water. This results in undesired abrupt changes in the compressive strength and elastic modulus at the cement–formation interface. In this study, a water-borne epoxy resin was applied as a strengthening material to reinforce the weakly consolidated shallow formation and protect the cement sheath from potential failure. The mechanical properties of the unconsolidated clay were tested, including their changes with increases in the temperature and curing time. In addition, the effects of the seawater, cement slurry alkaline filtrate, and saltwater drilling fluid were evaluated. As confirmed by the results, the strengthening fluid was excellent at reinforcing the unconsolidated clay, with a compressive strength of 2.49 MPa (after curing for 7 days), even at a dosage of 5%. A cement slurry filtrate with a high pH was suitable to produce the required strengthening of the formation, especially its early age strength. It should also be pointed out that the used fluid exhibited good compatibility with the saltwater drilling fluid and seawater behaved well as a diluent for the strengthening fluid.

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