Ultimate lateral pressures exerted on buried pipelines by the initiation of submarine landslides

Abstract

Submarine slope instabilities are considered one of the major threats for offshore buried pipelines. This paper presents a novel method to evaluate the ultimate pressure acting on a buried pipeline during the liquefaction of an inclined seabed. Small-scale model tests with pipes buried at three different embedment ratios have been conducted at an enhanced centrifugal acceleration condition. A high-speed, high-resolution imaging system was developed to quantify the soil displacement field of the soil body and to visualize the development of the liquefied zone. The measured lateral pressures were compared with the hybrid approach proposed for the landslide–pipeline interaction in clay-rich material by Randolph and White (2012) and Sahdi et al. (2014). The hybrid approach is proved to be able to predict later pressures induced by the movement of (partially) liquefied sand on buried pipelines. It is found that the fluid inertia (fluid dynamics) component plays an important role when the non-Newtonian Reynolds number >~2 or the shear strain rate > 4.5 × 10−2 sec−1.

Examining the effect of Debris Flow on Oil and Gas Pipelines Using Numerical Analysis

“…Rigorous analysis for 36 cases was performed to investigate the combined effect of the impact pressure, impact angle, and wall thickness, as revealed in Table 2. These three parameters are considered very influential for the strength of the pipeline during debris flow [33][34][35]. A different set of parameters were considered in the analysis to observe the critical condition of the pipeline when approaching failure in a broad spectrum, which is discussed in the subsequent sections.…”

Excess Pore Pressure Migration Analysis Due to High Embankment Construction – Case Study East Kalimantan

“…Landslides or ground failures are one of the most critical external forces affecting the pipeline. Numerous studies have investigated the behavior of buried pipelines subjected to axial and lateral forces due to ground failure (e.g., (Trautmann and O'Rourke, 1985;Shen et al, 2009;Yuan et al, 2014;Al-Khazaali and Vanapalli, 2018;Zhang and Askarinejad, 2021). Nevertheless, most of these studies were based on laboratory tests involving sand material and rainfall influence, yet none involving soft clay and excess pore pressure.…”