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    <title>Transport Research International Documentation (TRID)</title>
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    <atom:link href="https://trid.trb.org/Record/RSS?s=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" rel="self" type="application/rss+xml" />
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    <copyright>Copyright © 2026. National Academy of Sciences. All rights reserved.</copyright>
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    <managingEditor>tris-trb@nas.edu (Bill McLeod)</managingEditor>
    <webMaster>tris-trb@nas.edu (Bill McLeod)</webMaster>
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      <title>Transport Research International Documentation (TRID)</title>
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      <link>https://trid.trb.org/</link>
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    <item>
      <title>Deformation Mechanism and Influence of Surface Pumping Control in Shallow-Buried Tunnel in Water-Rich Fully Weathered Granite</title>
      <link>https://trid.trb.org/View/2640203</link>
      <description><![CDATA[Fully weathered granite exhibits high water sensitivity and poor water stability, making tunnel construction in water-rich fully weathered granite formations challenging. This study analyzes the water sensitivity of fully weathered granite and the impact of surface pumping on the deformation of shallow-buried, water-rich fully weathered granite tunnels, focusing on the Beitouling Tunnel in China. Geotechnical tests and numerical simulations are used to investigate these effects. The key findings are as follows: 1) The fully weathered granite in the project shows significant water sensitivity, with mechanical strength parameters decreasing as moisture content increases. Despite this, the stress-strain characteristics at various moisture levels exhibit strain-hardening behavior, and the failure mode is consistently “waisted drum-shaped.” The granite’s particle and compositional characteristics also contribute to surge disasters; 2) As the water level drops, groundwater moves toward the bottom of the “pumping funnel” along the pumping curve. Below this curve, intense seepage is observed around the tunnel lining, causing sidewall convergence and invert heaving. A “preventive layer” forms beneath the tunnel, reducing groundwater seepage toward the unsupported face; and 3) When pumping reaches the first excavation stage’s bottom, crown settlement decreases by more than 50% compared with the initial water level, providing the best control. However, sidewall convergence increases by 9% to 13%, and invert uplift rises by 23% to 36% when pumping reaches the tunnel invert.]]></description>
      <pubDate>Mon, 15 Dec 2025 09:25:55 GMT</pubDate>
      <guid>https://trid.trb.org/View/2640203</guid>
    </item>
    <item>
      <title>Tunneling- And Dewatering-Induced Rapid Differential Ground Rebound and Delayed Subsidence Measured by InSAR in an Urban Environment</title>
      <link>https://trid.trb.org/View/2543882</link>
      <description><![CDATA[During the excavation of the Alaskan Way Viaduct replacement tunnel in Seattle, Washington, a 17.5 m diameter tunnel boring machine (TBM) nicknamed “Big Bertha” was damaged after encountering unexpected subsurface conditions. Significant dewatering of multiple aquifers was required to reach the TBM for repairs. Groundwater drawdown and soil consolidation associated with dewatering created a 0.4 km² region of initial subsidence with maximum vertical settlements exceeding 2.5 cm between August and December 2014. Dewatering wells remained operational until January 2016 and likely contributed to observed groundwater drawdown in areas outside the region of initial subsidence. To determine how an urban landscape with complex and poorly constrained geologic and hydrologic conditions responds to an extended period of dewatering within multiple aquifers, the rate, duration, spatial extent, and magnitude of dewatering-related displacements were analyzed by combining three paths of Sentinel-1 interferometric synthetic aperture radar data spanning November 2014 to October 2019 into a time series of vertical surface deformation using the minimum acceleration algorithm. The results show that post-dewatering ground rebound within this complex hydrogeologic system occurred at faster rates and with more significant spatial deformation variability than initial subsidence, reaching rates of up to 17 cm/year coupled with potentially hazardous differential rebounds across short distances. In addition, prolonged groundwater pumping at depths greater than 60 m appears to have induced delayed subsidence over a larger area of ∼20 km², reaching magnitudes of up to 3 cm and lasting for over 3 years after the cessation of pumping.]]></description>
      <pubDate>Tue, 29 Apr 2025 17:02:44 GMT</pubDate>
      <guid>https://trid.trb.org/View/2543882</guid>
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    <item>
      <title>Hydraulic Anisotropy of Varved Glacial Silts and Its Influence on Dewatering Behavior</title>
      <link>https://trid.trb.org/View/2452739</link>
      <description><![CDATA[This paper presents the evaluation of dewatering behavior of varved glacial silts for cut-and-cover construction of an underground subway station in Manhattan, New York. Diaphragm walls were adopted as retaining walls with an embedded length below the excavation base for groundwater cutoff. The dewatering system consisted of a combination of sumps and vertical pressure relief ejector wells. Back-analysis of pumping test results using numerical seepage modeling indicated the glacial silts were highly anisotropic with the ratio of horizontal to vertical hydraulic conductivity in the order of 5−10. Comparison of piezometric measurements inside and outside of the excavation showed the external groundwater table was not significantly influenced by dewatering operations inside the excavation. However, the varved character of the glacial silts resulted in low residual piezometric pressures beneath the station invert slab after the pressure relief system was deactivated. It was postulated that the ejector wells promoted rapid dewatering of the glacial silts below the excavation subgrade via horizontal flow through sandy seams between the varved clay laminations during active dewatering. Upon deactivation of the pressure relief system, restoration of piezometric pressures was inhibited by the much slower recharge of groundwater in the vertical direction across the less permeable clayey laminations. Residual piezometric pressures in the dewatered zones were observed to be lower where the diaphragm walls were deeper reflecting the increased frequency of varved laminations at depth.]]></description>
      <pubDate>Sat, 30 Nov 2024 11:49:35 GMT</pubDate>
      <guid>https://trid.trb.org/View/2452739</guid>
    </item>
    <item>
      <title>Study on the influence of deep foundation pit excavation on the deformation of adjacent viaduct pile foundation</title>
      <link>https://trid.trb.org/View/2387127</link>
      <description><![CDATA[In order to study the influence of deep foundation pit excavation on the deformation of adjacent viaduct pile foundation in water-rich karst environment, a three-dimensional finite element analysis model was established, and the dewatering process of deep foundation pit was simulated. The results show that with the increasing of pile depth, the horizontal displacement of pile foundation is larger at the top and smaller at the bottom. The dewatering of deep foundation pit has influence on the bending moment and axial force of adjacent viaduct pile foundation, but they are in a relatively safe range. The horizontal displacement of bridge pile is negatively correlated with the distance between bridge pile and deep foundation pit, the supporting stiffness of deep foundation pit and the elastic modulus of the first layer soil.]]></description>
      <pubDate>Thu, 08 Aug 2024 14:52:04 GMT</pubDate>
      <guid>https://trid.trb.org/View/2387127</guid>
    </item>
    <item>
      <title>Ground Behavior due to Dewatering Inside a Foundation Pit Considering the Barrier Effect of Preexisting Building Piles on Aquifer Flow</title>
      <link>https://trid.trb.org/View/2364986</link>
      <description><![CDATA[Building and ground settlement due to construction dewatering is a well-studied topic. However, most previous investigations have not considered the barrier effect of an adjacent underground structure on the drawdowns and resulting settlements. In this study, the barrier effect and its influence during construction dewatering for a metro station foundation pit is investigated. There are five aquifers at the foundation pit site, and a row of buildings supported on pile foundations, which act as an underground barrier to flow, is present on one side of the pit. On the other sides, there are no deep underground structures to impede groundwater flow. Field monitoring of the groundwater level drawdown, diaphragm wall movement, and ground and building settlements on both sides of the pit was carried out during dewatering. The results indicate that on the side with the pile foundations, the groundwater level drawdown, ground settlement, differential settlement, and angular distortion of building incurred by dewatering were relatively greater, but the diaphragm wall movements were relatively smaller. The effect of preexisting barriers should be considered in the assessment of construction dewatering-induced drawdowns, soil settlements, and building movements.]]></description>
      <pubDate>Wed, 01 May 2024 09:46:36 GMT</pubDate>
      <guid>https://trid.trb.org/View/2364986</guid>
    </item>
    <item>
      <title>Analysis of Effect of Dewatering with Diaphragm Wall in Xiamen East Passageway</title>
      <link>https://trid.trb.org/View/2281804</link>
      <description><![CDATA[Xiamen east passageway Xiang'an subsea tunnel under construction is the first subsea tunnel in China. CRD method is adopted for the unfavourable geological conditions with enriched groundwater on shallow-buried excavation area. In order to reduce the effects of groundwater on stability of surrounding rock to ensure the safety construction, the method combines diaphragm wall and dewatering wells was introduced. For the purpose of working out the effect of this method by CRD1, three excavation ahead, the authors have employed two ways, in-situ monitoring and numerical simulation, to analyze the arch-crown settlement, horizontal convergence and internal forces of tunnel supports by the comparison between before and after dewatering. The results turned out to be perfectly matched by comparison and analysis. The research indicates that the arch-crown settlement approximately has a 50% drop while the horizontal convergence is about 30% lower after dewatering; meanwhile, the safety factors of tunnel supports are increased obviously. As a result, the results can provide experience for the latter construction of Xiang'an subsea tunnel as well as the similar projects.]]></description>
      <pubDate>Fri, 19 Apr 2024 09:38:53 GMT</pubDate>
      <guid>https://trid.trb.org/View/2281804</guid>
    </item>
    <item>
      <title>Venterspost Town and Village, South Africa: A Sinkhole Farm or Developable Land?</title>
      <link>https://trid.trb.org/View/2225431</link>
      <description><![CDATA[As a result of dewatering in the Venterspost Groundwater Compartment, Far West Rand, South Africa, numerous catastrophic sinkholes occurred in the surrounding area of Venterspost Town. Due to this large occurrence of events, this particular area, where the access road to Venterspost crosses the Wonderfontein Stream, became known as the `sinkhole farm". Despite this dramatic history barely 30 years ago, the demand for developable land has required that development in Venterspost Town, with its excellent but abandoned infrastructure, be reconsidered. In the late 1990's the South African Council for Geoscience (CGS) classified the Town into zones of development suitability based on their risk according to the affects of dewatering. While stands considered safe for development may be reused and the poorer areas left abandoned, a dilemma exists for the road joining the Town and Westonaria however. The mining groups which were the responsible parties for the dewatering of the area are concerned that continued use, and even increased use due to the arrival of new residents, of the access road could place the public at risk. Westonaria on the other hand, as the local municipal authority, desperately need this road to be able to service Venterspost Town which is part of its municipal area.]]></description>
      <pubDate>Thu, 30 Nov 2023 10:48:34 GMT</pubDate>
      <guid>https://trid.trb.org/View/2225431</guid>
    </item>
    <item>
      <title>A Study on Electrokinetic Dewatering of Saturated Soil</title>
      <link>https://trid.trb.org/View/2113108</link>
      <description><![CDATA[Differential settlements of foundation rested on saturated soil may lead to a disaster if not appropriately studied. Conventional dewatering techniques are time-consuming and have some limitations. Electrokinetic dewatering is one of the effective methods used to remove water from saturated clay having low permeability. The present study deals with a series of laboratory experiments performed on saturated clay to study the influence of (i) spacing of electrodes, (ii) configuration of electrodes, (iii) number of cathodes and anodes, and (iv) pH of soil on the performance of electrokinetic dewatering. A custom-designed wooden watertight box with internal dimensions of 40 cm length, 40 cm breadth, and 30 cm height was used for experiments. Hollow circular stainless steel tubes with 1.9 cm diameter, 25 cm length having perforations were used as electrodes. Water collected at the cathode was removed and measured manually. The results confirm that increasing the spacing between the anode and cathode causes more area under the influence of electric field, which increases dewatering efficiency. One-dimensional configuration is better than rectangular and hexagonal configurations. Dewatering increases with an increase in number of cathodes. A decrease in pH of soil results in less dewatering competence. This study will be beneficial for ground improvement projects carried out in marshy lands, coastal roads, etc., for improving subgrade soil.]]></description>
      <pubDate>Thu, 15 Jun 2023 11:10:16 GMT</pubDate>
      <guid>https://trid.trb.org/View/2113108</guid>
    </item>
    <item>
      <title>Groundwater System Impacts on the US 63 Railway Underpass near Waterloo, Iowa</title>
      <link>https://trid.trb.org/View/1976250</link>
      <description><![CDATA[The Iowa Department of Transportation (DOT) replaced the existing railroad underpass on US 63 in Waterloo between Dane and Newell Streets with an overpass. The existing underpass was initially constructed below the water table; therefore, the Iowa DOT had to continuously use a groundwater dewatering system to prevent water from entering the underpass. With the overpass construction project, the Iowa DOT aimed to change the existing well system to avoid unknown impacts on the water table. However, groundwater level monitoring was required throughout construction to avoid endangering neighboring properties. The Iowa DOT used nine dewatering pumps to control the high water table in the area during overpass construction. The work described in this report aimed to observe groundwater levels at and around the construction site and assess the effects of dewatering, which occurred between November 5, 2017 and March 25, 2019, and a groundwater suppression system (GSS), which began operation on October 15, 2019. Water levels were monitored in several observation wells and reported over 76 months that encompassed four periods: before dewatering, during dewatering, between dewatering and operation of the GSS, and during operation of the GSS. Analysis of the time series of water levels and statistical analysis of the mean water levels and variances during the four periods provided a picture of the behavior of the water table and led to the following conclusions: (1) Water levels in wells farther from the overpass were not greatly affected by the operations at the site. This observation confirms previous findings. (2) Dewatering lowered the water table by a large amount around the construction area. The water levels rose quickly by the end of the dewatering period; mean water levels before and after dewatering (but before groundwater suppression) appeared similar, though the statistical analysis indicated that most mean levels were significantly different at the 5% level. (3) The GSS has lowered the water table by about 1 to 2 ft. Statistical analysis supports the observation by showing that water levels during suppression were significantly different from the levels in periods without suppression or dewatering. (4) The variance of the water levels was smallest during the period with groundwater suppression. This observation suggests that the GSS has stabilized the water levels near the overpass.]]></description>
      <pubDate>Mon, 06 Jun 2022 16:54:25 GMT</pubDate>
      <guid>https://trid.trb.org/View/1976250</guid>
    </item>
    <item>
      <title>Benefits of Alternative Criteria for Scheduling Dewatering Events at Navigation Locks and Repairing or Replacing Lock Components</title>
      <link>https://trid.trb.org/View/1942852</link>
      <description><![CDATA[The failure of critical components at navigation locks can cause unscheduled outages that impose high costs on shippers. Presently, the USACE requires that each hydraulic steel structure be inspected at least once every 25 years. At navigation locks, this requires dewatering because several critical components are located under water. Where budgets are limited, this may devolve into the practice of dewatering once every 25 years unless the failure of a critical component causes an unscheduled outage. Nine alternatives to the current practice were evaluated by comparing their costs over a 50-year planning horizon. An empirical transition matrix was used to simulate the degradation and failure of lock components, their repair or replacement, and the occurrence of scheduled and unscheduled outages. The optimal alternative minimizes the present value of lock dewatering cost, component repair and replacement cost, and shipper carrier cost. Results show that, in waterways where the ratio of scheduled to unscheduled shipper carrier cost is low, probabilistic scheduling criteria and structural health monitoring are optimal. These results demonstrate that preemptive maintenance strategies are cost effective.]]></description>
      <pubDate>Tue, 10 May 2022 14:35:18 GMT</pubDate>
      <guid>https://trid.trb.org/View/1942852</guid>
    </item>
    <item>
      <title>Evaluation of the Filtration Effectiveness of Dewatering Bags and Assessment of Potential Improvements</title>
      <link>https://trid.trb.org/View/1850291</link>
      <description><![CDATA[Geotextile dewatering bags are used on construction sites to treat sediment-laden construction discharge water pumped from excavations or behind cofferdams. Although these bags have become popular because of their small footprint on the construction site, recent observations have revealed that in some cases, fine sediment can pass through these bags, causing an increase in the turbidity of receiving waters. The Virginia Department of Transportation (VDOT) has approved a number of geotextiles for use as dewatering bags based on the geotextiles’ physical characteristics such as permittivity and apparent opening size. Because of the concerns with fine sediment, questions regarding the filtration effectiveness of these dewatering bags have been raised. The purpose of this study was to evaluate the filtration effectiveness of dewatering bags approved for use by VDOT and selected dewatering bags that are not currently approved by VDOT but are claimed to provide a higher level of filtration performance. In addition, a preliminary investigation of methods of improving the filtration effectiveness of dewatering bags including the use of straw bales and anionic polymer flocculants was conducted. The results of the study indicated that the filtration effectiveness of geotextile dewatering bags can be highly variable based on the soil characteristics of the construction site. Specifically, sites with soils categorized as “fine-grained” performed poorly compared to sites with coarser soil gradations. An evaluation of VDOT’s specifications and those from other states indicated that VDOT’s material specifications are appropriate for maximizing the retention of sediments. However, VDOT’s implementation guidance for dewatering bags, provided in Specification EC-8 of VDOT’s Road and Bridge Standards, needs to be updated to include the proper methods for sizing, siting, and monitoring dewatering bags. Evaluations of secondary sediment barriers (i.e., straw bales) and flocculants, though limited by the study’s testing apparatus, showed promising results when used to improve the retention of fine sediments by dewatering bags as a system. These potential improvements were further supported by the literature. An evaluation of a dewatering bag not approved for use by VDOT constructed from a woven geotextile showed that when treating the same volume of construction discharge water with similar sediment concentrations and characteristics, it was capable of maintaining a higher flow rate for a longer period of use compared to nonwoven geotextile dewatering bags. However, woven geotextile dewatering bags provided a lower degree of sediment retention during the initial stages of use. Last, dewatering bags constructed from nonwoven geotextiles showed a degree of stretching with use. It is hypothesized that this stretching could be used to indicate when a dewatering bag is nearing rupture in the field.]]></description>
      <pubDate>Mon, 17 May 2021 14:58:50 GMT</pubDate>
      <guid>https://trid.trb.org/View/1850291</guid>
    </item>
    <item>
      <title>Deformation Responses and Mechanical Mechanism of Existing Tunnel due to New Building Construction</title>
      <link>https://trid.trb.org/View/1770182</link>
      <description><![CDATA[This study mainly investigated the variation law and mechanical mechanism of surrounding earth pressure and deformation of an existing tunnel, caused by dewatering, foundation excavation, building loading, and groundwater recovery. According to different dewatering schemes, two modes were established: nonisolated dewatering unloading-loading mode and isolated dewatering unloading-loading mode. Through large-scale similar materials model test, the variation law of deformation and surrounding earth pressure of adjacent tunnel under complex unloading-loading conditions was preliminarily revealed. Based on the size of the prototype project, the test results were further verified by the numerical simulation. The mechanical mechanism of tunnel deformation in different construction stages was analyzed after the comparative study. The results show that the tunnel structure deformation, vertical and horizontal displacement, and torsion occur in the process of building construction. In the nonisolated dewatering unloading-loading mode, the decrease or rise of the groundwater level significantly reduces (maximum 27.85%) or increases (maximum 35.19%) the surrounding earth pressure of the tunnel. The decrease or increase of the horizontal total stress was much greater than that of the vertical total stress, which leads to the deformation of tunnel structure. The vertical displacement of the tunnel is generally settlement, which mainly occurs in the stage of dewatering and building loading, accounting for 83.21%–100.00% and 25.11%–40.34% of the total settlement, respectively. In the stage of foundation pit excavation and groundwater recovery, the tunnel rises. In the horizontal direction, the tunnel moves towards the foundation pit, mainly in the excavation stage, accounting for 82.77%–86.30% of the maximum value. Due to the uneven change of displacement field and stress field of soil outside the foundation pit, the tunnel torsion occurs. In the isolated dewatering unloading-Loading mode, the change of groundwater has little effect on the tunnel. In the stage of excavation and construction load, the variation law of tunnel surrounding earth pressure and deformation is similar in the two modes.]]></description>
      <pubDate>Thu, 29 Apr 2021 17:28:46 GMT</pubDate>
      <guid>https://trid.trb.org/View/1770182</guid>
    </item>
    <item>
      <title>Design of Groundwater Extraction in Open Cut Foundation Pit and Simplified Calculation of Ground Subsidence due to Dewatering in Sandy Pebble Soil Strata</title>
      <link>https://trid.trb.org/View/1697085</link>
      <description><![CDATA[In order to study the design of incomplete well point for groundwater extraction in open cut foundation pit in which the inner and outer aquifers are not completely isolated and the change mechanism of ground subsidence due to dewatering in the foundation pit, an open cut foundation pit for a subway station on Chengdu Metro Line 6 is taken as an example; meanwhile, the typical sandy pebble soil strata are also considered as a research object in this paper. Firstly, a new method for designing groundwater extraction in the open cut foundation pit is presented and applied to the practical project. The dewatering funnel curve is derived based on Dupuit's assumption, and the ground subsidence around the foundation pit due to groundwater extraction is calculated using the stratification summation method as well as considering the effect of seepage force. The finite difference software FLAC3D is employed to simulate the groundwater extraction process in the foundation pit, and the simulation of groundwater extraction by single well point and group well points is also carried out and the unapparent effect of group well points is obtained. The comparison among on-site monitoring, theoretical calculation, and numerical simulation shows that these values have the same trend in indicating ground subsidence, and the conventional stratification summation method is conservative, and the algorithm considering the effect of seepage force is more accurate. Therefore, the ground subsidence curve caused by groundwater extraction in the foundation pit is presented. The above research methods and results can be applicable for practical engineering and be used to guide the design and construction of groundwater extraction in the foundation pit by using the open cut method in sandy pebble soil strata.]]></description>
      <pubDate>Wed, 22 Jul 2020 14:40:48 GMT</pubDate>
      <guid>https://trid.trb.org/View/1697085</guid>
    </item>
    <item>
      <title>Laboratory and Field Study of Electroosmosis Dewatering for Pavement Subgrade Soil</title>
      <link>https://trid.trb.org/View/1508987</link>
      <description><![CDATA[Electroosmosis (EO) is considered a promising technique for reducing water content in soft soils. In this study, a multiscale experiment was conducted to investigate the effectiveness of EO in controlling the water content of in-service pavement subgrade soil. First, the effect of EO dewatering was investigated through a laboratory-scale experiment considering three types of soils and two levels of electric voltages. Then a field-scale pavement subgrade was constructed to evaluate the engineering feasibility of EO. Conventional natural drainage was also investigated for the purpose of comparing the efficiency of EO dewatering. Results from the laboratory-scale experiments indicate that natural drainage is only useful for sand and silt, but EO dewatering works well for clay because the average reduction of the water content of the two clays is 3.47 and 3.78% with a voltage of 24  V/m, and the dewatering performance is improved with an increase in voltage. The validity of EO dewatering in reducing the water content of clay ground is confirmed through the field-scale experiment.]]></description>
      <pubDate>Thu, 17 May 2018 14:46:03 GMT</pubDate>
      <guid>https://trid.trb.org/View/1508987</guid>
    </item>
    <item>
      <title>I-40 Along the Cumberland Escarpment Highway Instability, Historic Reviews, and Remedial Concepts</title>
      <link>https://trid.trb.org/View/1503029</link>
      <description><![CDATA[The eastern Cumberland Plateau Escarpment, separating the Cumberland Plateau and the Valley and Ridge Physiographic Provinces, has a record of hampering highway construction in central East Tennessee, due to a combination of steep natural slopes, thick accumulations of colluvium, and the presence of swelling clay from the Pennington Formation. In that record is the 1968 construction failure of approximately 370 meters of eastbound Interstate Highway 40 embankment. Planned as an up to 43- meter high embankment across the Escarpment, the Tennessee Department of Transportation (TDOT) responded to the landslide and embankment failure through geometric modifications and slide mass drainage using dewatering wells and horizontal drains. Even with these mitigation measures and periodic installation of additional horizontal drains, movement of the slide mass has continued through the ensuing decades. Measurements in 2010 had shown displacement on the order of 25 millimeters per year, requiring annual resurfacing of the pavement. Interstate Highway 40 (I-40) is a heavily-traveled, east-west interstate through the mid-section of the United States. Traffic safety concerns with a traffic-disruption threat led TDOT to request a detailed review of the available project documentation by Golder Associates Inc. Since the initial slide, limited topographic, geologic, and geotechnical data have been gathered and assimilated for evaluation of the slide. As a result of Golder’s review, additional slope inclinometers and automated vibrating-wire piezometers were installed to better define the conditions and their variation with time. A limited laboratory testing program was conducted for evaluating potential remediation options. Installation of a system of dewatering wells and horizontal drainage was initiated in late 2011 in an effort to mitigate further displacement. Implementation of these drainage measures was still underway at the time of publication. This paper presents the historical background, results from the first year of slope and groundwater monitoring, dewatering program, and feasible remediation options available to TDOT in order to improve the margin of safety on this career-spanning slope failure.]]></description>
      <pubDate>Wed, 28 Feb 2018 09:34:24 GMT</pubDate>
      <guid>https://trid.trb.org/View/1503029</guid>
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