Effect of the in situ leaching solution of ion-absorbed rare earth on the mechanical behavior of basement rock

The Knothe time function is a classical method in predicting the ground mining subsidence. Nevertheless, it does not take the observation data into account in the prediction process. The Kalman filter method can solve this issue at large extent. Taking a coal mining work face of Xishan Coalfield as an example, this research compares the performance of the traditional Knothe time function and that of the improved Knothe time function by using the Kalman filter method. The comparison results show that through an improvement by using the Kalman filter method, the RMSE is improved from 133.4 mm to 78.3 mm; ME, from 91.9 mm to 3.1 mm; and the relative error, from 8.1% to 5.7%. Meanwhile, the improved model has good astringency. These verify that the improved model has higher accuracy and reliability. Hence, this research presents an effective method in predicting ground subsidence of mining area by improving the Knothe time function using the Kalman filter method.

Section: Knothe Time Function Modelmentioning

confidence: 99%

An Improved Knothe Time Function Model in the Prediction of Ground Mining Subsidence by Using the Kalman Filter Method

Zhang

2022

“…During the terminal low sea level, about 23000 years ago, the sea level began to decline (marine regression), reaching a minimum level (about 150 m lower than the present level) about 15000 years ago, the East China Sea shelf was exposed into a wide land plain, the Okinawa Trough bordered the coastline, and the ancient Yangtze River estuary was extended, bringing a large amount of sediment; the sea level rose during the interglacial period (marine transgression), the shelf was gradually submerged by seawater, and around 7000 years ago, the sea level rose to the present level. In the process of sea level rise, the tide relocated and modified the sediments, moving the sediments in the tidal trench to the top of the ridge, forming a geomorphic pattern of tidal sand ridges and troughs [28][29][30][31][32][33].…”

Section: Analysis Of Engineering Geologicalmentioning

confidence: 99%

Analysis of Engineering and Geological Conditions of International Submarine Optical Fiber Cable Routing in the East China Sea Section

Zhang

Fan

Nan³

et al. 2022

The East China Sea section of the Chinese international submarine optical fiber cable generally starts from the Shanghai coast, crosses the East China Sea shelf and continental slope to the east, and intersects with the international optical fiber cable system in Okinawa Trough. In this paper, the regional tectonic, seismic, and other environmental conditions of the East China Sea section of the international submarine optical cable are briefly described based on the previous data. Additionally, the geological engineering conditions of the international optical cable routing in the East China Sea area will be analyzed based on the field investigation data such as multibeam, side-scan sonar, shallow stratigraphic profile, sediment sampling, and cone penetration test (CPT). It is found that the main geological factors in the East China Sea shelf area are submarine scouring, sandwave, shallow gas, and hard seabed; in the land slope area are steep slope, submarine valley, rock, landslide, and shallow gas (pockmark); and in the Okinawa Trough area are gully, sea mound/seamount, rock, shallow gas, fault, and hard strata outcrop. This paper briefly analyzes the impact of each geological disaster factor on the submarine cable project and proposes solutions for providing essential information and some scientific basis for designing, constructing, operating, and maintaining international submarine optical fiber cables in the East China Sea area.

“…The process of the experiment is as follows: first, the empty vehicle is rolled back and forth; then, the half loaded vehicle is rolled back and forth; then, the full load is rolled back and forth; finally, the cover plate is added, and then, the full load is rolled back and forth [24][25][26][27][28][29][30][31][32].…”

Section: Experimental Investigationmentioning

confidence: 99%

Study and Analysis on Stress Safety Judgment Method of Heavy Vehicle Rolling on Long-Distance Pipeline

Shi

Jiang

Li³

et al. 2022

With the rapid increasing mileage of China’s long-distance oil and gas pipelines, the intersection construction with other civil engineering, encroachment by invading the pipeline route, and other third-part problems occurred occasionally. Heavy vehicles rolling the serving pipeline have become one of the inevitable safety risks. The field test method of three in-service long oil and gas pipelines under heavy vehicle rolling is elaborated. The pipeline stress and soil pressure during tests are monitored and analyzed. The parametric model of pipe mechanical response under heavy vehicle rolling and stacking load is established, and the quantitative feedback of each parameter on pipeline stress safety response under heavy vehicle rolling is formed. The results show that the influence factors such as vehicle weight, vehicle speed, buried depth of pipeline, horizontal distance and cover plate on the stress state, vertical displacement state, and contact stress of pipe soil interface are highly consistent with the finite element method and test method, which could be a guideline for the safety assessment at rolling site.