Geomechanical and Hydrodynamic Fields in Producing Formation in the Vicinity of Well, Considering Rock Mass Permeability-Actual Stress Relationship

This paper presents the results of a preliminary study of a self-excited acoustical system (SAS) for nondestructive testing (NDT). The SAS system was used for mine excavation stresses examination. The principle of operation of the SAS system based on the elastoacoustical effect is presented. A numerical analysis of the excavation was carried out considering the stress factor. An equivalent model based on a two-degree-of-freedom system with a delay has been developed. This model allowed to determine the relation which relates the frequency of the self-excited system to the stress level in the studied ceiling section. This relationship is defined by the elastoacoustic coefficient. The test details for anchorages in laboratory conditions and Wieliczka Salt Mine were presented. This research details of a method for creating actual stress maps in the ceiling of a mine excavation. The results confirmed the possibility of using the new measurement system to monitor the state of stresses in the rock mass.

Download Full-text

Estimation of rock mass permeability using variation in hydraulic conductivity with depth: experiences in hard rocks of western Turkey

Bulletin of Engineering Geology and the Environment ◽

10.1007/s10064-017-1058-8 ◽

2017 ◽

Vol 77 (4) ◽

pp. 1663-1671 ◽

Cited By ~ 4

Author(s):

Vincenzo Piscopo ◽

Antonella Baiocchi ◽

Francesca Lotti ◽

Emre A. Ayan ◽

Alper R. Biler ◽

...

Keyword(s):

Rock Mass ◽

Hydraulic Conductivity ◽

Western Turkey ◽

Hard Rocks ◽

Rock Mass Permeability

Download Full-text

A New Method for Real-Time Monitoring of Grout Spread Through Fractured Rocks

MRS Proceedings ◽

10.1557/proc-1107-577 ◽

2008 ◽

Vol 1107 ◽

Cited By ~ 1

Author(s):

Alasdair E. Henderson ◽

Iain A. Robertson ◽

John M Whitfield ◽

Graham F.G. Garrard ◽

Nicholas G. Swannell ◽

...

Keyword(s):

Rock Mass ◽

Real Time ◽

Fractured Rock ◽

Field Trials ◽

New Method ◽

Real Time Monitoring ◽

Retrieval Method ◽

Extensive Field ◽

Grout Spread ◽

Rock Mass Permeability

AbstractReducing water ingress into the Shaft at Dounreay is essential for the success of future intermediate level waste (ILW) recovery using the dry retrieval method. The reduction is being realised by forming an engineered barrier of ultrafine cementitious grout injected into the fractured rock surrounding the Shaft. Grout penetration of 6m in <50μm fractures is being reliably achieved, with a pattern of repeated injections ultimately reducing rock mass permeability by up to three orders of magnitude.An extensive field trials period, involving over 200 grout mix designs and the construction of a full scale demonstration barrier, has yielded several new field techniques that improve the quality and reliability of cementitious grout injection for engineered barriers.In particular, a new method has been developed for tracking in real-time the spread of ultrafine cementitious grout through fractured rock and relating the injection characteristics to barrier design. Fieldwork by the multi-disciplinary international team included developing the injection and real-time monitoring techniques, pre- and post injection hydro-geological testing to quantify the magnitude and extent of changes in rock mass permeability, and correlation of grout spread with injection parameters to inform the main works grouting programme.

Download Full-text