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The paleomagnetic results from Lhasa terrane are commonly used to constrain the shape and paleoposition of the southern margin of Asia prior to the India-Asia collision (

Large deformation and failure of soft rock are pressing problems in the mining practice. This paper provides a case study on failure mechanisms and support approaches for a water-rich soft rock roadway in tectonic stress areas of the Wangzhuang coal mine, China. Mechanic properties of rock mass related to the roadway are calibrated via a geological strength index method (GSI), based on which a corresponding numerical simulation model is established in the Universal Discrete Element Code (UDEC) software. The failure mechanism of the roadway under water-saturating and weathering conditions is revealed by field tests and numerical simulation. It is found that the stress evolution and crack development are affected by weathering and horizontal tectonic stresses. The roadway roof and floor suffer from high stress concentration and continuous cracking, and are consequently seen with rock failure, strength weakening, and pressure relief. Unfortunately, the current support system fails to restrain rock weathering and strength weakening, and the roadway is found with serious floor heave, roof subsidence, and large asymmetric deformation. Accordingly, a new combined support system of “bolt–cable–mesh–shotcrete + grouting” is proposed. Moreover, numerical simulation and field testing are conducted to validate the feasibility and effectiveness of the proposed approach, the results of which demonstrate the capacity of the proposed new support method to perfectly control the surrounding rock. Findings of this research can provide valuable references for support engineering in the soft rock roadway under analogous geological conditions.

Shutdown operations in olefin plants generate extensive flare emissions, which cause adverse environmental and societal impacts as well as large amounts of raw material and energy losses that could supposedly be unitized to generate much more needed products. Consequently, shutdown optimization for flare minimization is crucially important to all stake holders. However, the current practice for shutdown flare minimization almost exclusively depends on experienced operators, engineers, and plant administration. There is still a lack of systematic studies on how to cost‐effectively identify and examine shutdown flare minimization strategies through plant‐wide modeling and simulations. A novel process retrofit and shutdown operation strategy for flare minimization in an olefin plant is introduced. Plant‐wide dynamic simulations are employed to examine the operational feasibility and critical information during the plant shutdown operation. The proposed shutdown strategy could virtually reduce the flare emission significantly compared to historical records.