A Geotechnical Characterization of the Epikarst at the Clearwater Dam Site, Wayne County, Missouri

Bibliographic Details
Main Author:	Enzweiler, Kristen
Language:	English
Published:	Kent State University / OhioLINK 2012
Subjects:	Geological Geology Epikarst Karst Clearwater Dam Potosi Dolomite
Online Access:	http://rave.ohiolink.edu/etdc/view?acc_num=kent1343041565

id	ndltd-OhioLink-oai-etd.ohiolink.edu-kent1343041565
record_format	oai_dc
spelling	ndltd-OhioLink-oai-etd.ohiolink.edu-kent13430415652021-08-03T05:38:02Z A Geotechnical Characterization of the Epikarst at the Clearwater Dam Site, Wayne County, Missouri Enzweiler, Kristen Geological Geology Epikarst Karst Clearwater Dam Potosi Dolomite <p>The Clearwater Dam in Wayne County, Missouri, is a 154 foot (46.9 m) high zoned earth-fill structure constructed on Cambrian and Ordovician carbonate rocks, primarily for flood control. A sinkhole, 10 feet (3 m) across and 10 feet (3 m) deep, formed in January 2003 on the upstream face of the dam at an elevation of 570 feet (173.7 m). The sinkhole development was most likely a result of sediment loss through piping due to the epikarst solution features at the base of the dam. Epikarst is defined as the uppermost weathered zone of karstified rock with enhanced porosity and permeability compared to the underlying bulk rock. Epikarst formation progresses over time through stress release, weathering, and dissolution. The near surface weathered zone acts as a recharge zone for the underlying karst. The epikarst at the Clearwater Dam site is a highly variable zone. The zone spans a thickness of up to 100 feet (30.5 m) in the foundation of the dam. Upstream, the epikarst is exposed in an outcrop where it formed along the bedding planes, joints and top surface of the Potosi dolomite, roughly 30 feet (9.1 m) thick. These solution features and joints create serious seepage and piping problems for the dam. The dam has undergone remedial measures to install a cutoff wall to block the flow of water through the open cavities. </p><p>This study investigated the nature and causes of seepage problems in light of geologic conditions present at the Clearwater Dam site by evaluating outcrops and borehole logs provided by the U.S. Army Corps of Engineers and Gannett Fleming, Inc. It also characterized the epikarst layer in the dam foundation in terms of its geologic, hydrologic, and engineering properties. A representative site was chosen upstream from the right abutment of the dam which contained an outcropping of the Potosi dolomite and the overlying epikarst material. This site is locally known as “epikarst beach”. A detailed line survey was conducted to measure the orientation and other aspects of the joints. Epikarst material from the site was collected to perform absorption tests, specific gravity tests, unconfined compressive strength tests and direct shear tests. Laboratory testing revealed a much weaker and more porous rock than typical dolomite. Epikarst porosity is roughly 50%, specific gravity is half of standard dolomite, and absorption is twice that of dolomite. The unconfined compressive strength and shear strength parameters were significantly lower than dolomite, proving the epikarst is at least 50% weaker. However, there was some variation of strength between the different samples that may be attributed to the amount of chert and voids in the samples.</p> 2012-07-31 English text Kent State University / OhioLINK http://rave.ohiolink.edu/etdc/view?acc_num=kent1343041565 http://rave.ohiolink.edu/etdc/view?acc_num=kent1343041565 unrestricted This thesis or dissertation is protected by copyright: all rights reserved. It may not be copied or redistributed beyond the terms of applicable copyright laws.
collection	NDLTD
language	English
sources	NDLTD
topic	Geological Geology Epikarst Karst Clearwater Dam Potosi Dolomite
spellingShingle	Geological Geology Epikarst Karst Clearwater Dam Potosi Dolomite Enzweiler, Kristen A Geotechnical Characterization of the Epikarst at the Clearwater Dam Site, Wayne County, Missouri
author	Enzweiler, Kristen
author_facet	Enzweiler, Kristen
author_sort	Enzweiler, Kristen
title	A Geotechnical Characterization of the Epikarst at the Clearwater Dam Site, Wayne County, Missouri
title_short	A Geotechnical Characterization of the Epikarst at the Clearwater Dam Site, Wayne County, Missouri
title_full	A Geotechnical Characterization of the Epikarst at the Clearwater Dam Site, Wayne County, Missouri
title_fullStr	A Geotechnical Characterization of the Epikarst at the Clearwater Dam Site, Wayne County, Missouri
title_full_unstemmed	A Geotechnical Characterization of the Epikarst at the Clearwater Dam Site, Wayne County, Missouri
title_sort	geotechnical characterization of the epikarst at the clearwater dam site, wayne county, missouri
publisher	Kent State University / OhioLINK
publishDate	2012
url	http://rave.ohiolink.edu/etdc/view?acc_num=kent1343041565
work_keys_str_mv	AT enzweilerkristen ageotechnicalcharacterizationoftheepikarstattheclearwaterdamsitewaynecountymissouri AT enzweilerkristen geotechnicalcharacterizationoftheepikarstattheclearwaterdamsitewaynecountymissouri
_version_	1719422814595842048

A Geotechnical Characterization of the Epikarst at the Clearwater Dam Site, Wayne County, Missouri

Similar Items