For more information on specific projects related to this topic, see the following MEA Technical Bulletins:
UPDATE #21: Mine Subsidence Damage During Construction of Medical Center and Remedial Measures Taken
Forensic engineering is the study of why a certain structure or feature failed or why a problematic condition occurred. MEA staff have extensive experience with geoforensic investigations. These investigations are best undertaken by experienced, well qualified engineers.
The effects of groundwater seepage on levees, dams, impoundments, open and underground excavations, temporary water retaining structures, etc. can be very problematic and result in failure if not investigated, observed, addressed, and/or remediated. Moreover, field monitoring of dewatered areas such as in karst and underground mine works can be necessary to assess ground stability. Supplementing laboratory data and documented construction/mining information with survey data of the existing surface elevations and in-situ testing is sometimes required to fully analyze the conditions.
Ground Penetrating Radar, or GPR, is traditionally used on the ground surface to detect utilities and underground tanks or structures, and classify subgrade materials. MEA performs surface GPR surveys. At MEA, we have also developed a crosshole radar system that is used to detect and assess the presence of mine voids. For more information, see our Project Investigation Bulletin on Borehole Radar Use.
Under certain conditions, both seismic (refraction and reflection) and electric resistivity surveys have been used to assess subsurface conditions. For example, for the depth to bedrock, karst conditions, and the presence of mining may be assessed using these techniques. Therefore, these services can be offered for the following:
The existing mine conditions are investigated when establishing the risk of mine failure and to understand the potential grouting requirements. In order to accomplish these objectives on abandoned mines, MEA provides the following services:
MEA has executed numerous investigations of mine subsidence and the associated damage. MEA’s staff have extensive experience in forensics, and therefore are well suited to distinguish subsidence damage from damage from other causes.
Field Services and monitoring services MEA provides are below:
Geotechnical subsurface investigations are conducted to identify the soil profiles, groundwater levels, and any concern with the subsurface conditions. These investigations involve sampling soils and rock in order to determine their properties using our in-house laboratory. In order to achieve these objectives, MEA provides the following services:
A by-product of the mining process is large amounts of water-suspended solid waste, called tailings. The construction and continued performance of coal impoundment facilities is highly regulated and required monitoring.
MEA’s Field Services:
MEA has performed a significant number of investigations related to the performance of existing concrete and asphalt pavement systems. These investigations could be related to maintenance or quality control issues or from premature pavement failure.
Field services MEA provides:
Due to MEA’s extensive experience and expertise in mine stabilization via grouting, we have developed mine grouting standards which provide our client with the most cost-effective project, and at the same time, provides significant protection against “loopholes” in the specifications. Also, MEA has extensive experience in designing grout mixes with the most cost-effective performance in mind.
Actual mine grouting is a highly dynamic operation and thus requires on-site engineering. MEA field engineers and technicians work as a cohesive team to ensure that costs are controlled, productivity stays high, and deadlines are met.
Due to MEA’s extensive experience and expertise in mine stabilization via grouting, we have developed mine grouting standards which provide our client with the most cost-effective project, and at the same time, provides significant protection against “loopholes” in the specifications. Also, MEA has extensive experience in designing grout mixes with the most cost-effective performance in mind.
Actual mine grouting is a highly dynamic operation and thus requires on-site engineering. MEA field engineers and technicians work as a cohesive team to ensure that costs are controlled, productivity stays high, and deadlines are met.
