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Suggested Citation:"Part B." National Academies of Sciences, Engineering, and Medicine. 2019. Geotechnical Asset Management for Transportation Agencies, Volume 2: Implementation Manual. Washington, DC: The National Academies Press. doi: 10.17226/25364.
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Suggested Citation:"Part B." National Academies of Sciences, Engineering, and Medicine. 2019. Geotechnical Asset Management for Transportation Agencies, Volume 2: Implementation Manual. Washington, DC: The National Academies Press. doi: 10.17226/25364.
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Suggested Citation:"Part B." National Academies of Sciences, Engineering, and Medicine. 2019. Geotechnical Asset Management for Transportation Agencies, Volume 2: Implementation Manual. Washington, DC: The National Academies Press. doi: 10.17226/25364.
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Suggested Citation:"Part B." National Academies of Sciences, Engineering, and Medicine. 2019. Geotechnical Asset Management for Transportation Agencies, Volume 2: Implementation Manual. Washington, DC: The National Academies Press. doi: 10.17226/25364.
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Suggested Citation:"Part B." National Academies of Sciences, Engineering, and Medicine. 2019. Geotechnical Asset Management for Transportation Agencies, Volume 2: Implementation Manual. Washington, DC: The National Academies Press. doi: 10.17226/25364.
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Suggested Citation:"Part B." National Academies of Sciences, Engineering, and Medicine. 2019. Geotechnical Asset Management for Transportation Agencies, Volume 2: Implementation Manual. Washington, DC: The National Academies Press. doi: 10.17226/25364.
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Suggested Citation:"Part B." National Academies of Sciences, Engineering, and Medicine. 2019. Geotechnical Asset Management for Transportation Agencies, Volume 2: Implementation Manual. Washington, DC: The National Academies Press. doi: 10.17226/25364.
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Suggested Citation:"Part B." National Academies of Sciences, Engineering, and Medicine. 2019. Geotechnical Asset Management for Transportation Agencies, Volume 2: Implementation Manual. Washington, DC: The National Academies Press. doi: 10.17226/25364.
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Suggested Citation:"Part B." National Academies of Sciences, Engineering, and Medicine. 2019. Geotechnical Asset Management for Transportation Agencies, Volume 2: Implementation Manual. Washington, DC: The National Academies Press. doi: 10.17226/25364.
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Suggested Citation:"Part B." National Academies of Sciences, Engineering, and Medicine. 2019. Geotechnical Asset Management for Transportation Agencies, Volume 2: Implementation Manual. Washington, DC: The National Academies Press. doi: 10.17226/25364.
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Suggested Citation:"Part B." National Academies of Sciences, Engineering, and Medicine. 2019. Geotechnical Asset Management for Transportation Agencies, Volume 2: Implementation Manual. Washington, DC: The National Academies Press. doi: 10.17226/25364.
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Suggested Citation:"Part B." National Academies of Sciences, Engineering, and Medicine. 2019. Geotechnical Asset Management for Transportation Agencies, Volume 2: Implementation Manual. Washington, DC: The National Academies Press. doi: 10.17226/25364.
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Suggested Citation:"Part B." National Academies of Sciences, Engineering, and Medicine. 2019. Geotechnical Asset Management for Transportation Agencies, Volume 2: Implementation Manual. Washington, DC: The National Academies Press. doi: 10.17226/25364.
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Suggested Citation:"Part B." National Academies of Sciences, Engineering, and Medicine. 2019. Geotechnical Asset Management for Transportation Agencies, Volume 2: Implementation Manual. Washington, DC: The National Academies Press. doi: 10.17226/25364.
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Suggested Citation:"Part B." National Academies of Sciences, Engineering, and Medicine. 2019. Geotechnical Asset Management for Transportation Agencies, Volume 2: Implementation Manual. Washington, DC: The National Academies Press. doi: 10.17226/25364.
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Suggested Citation:"Part B." National Academies of Sciences, Engineering, and Medicine. 2019. Geotechnical Asset Management for Transportation Agencies, Volume 2: Implementation Manual. Washington, DC: The National Academies Press. doi: 10.17226/25364.
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Suggested Citation:"Part B." National Academies of Sciences, Engineering, and Medicine. 2019. Geotechnical Asset Management for Transportation Agencies, Volume 2: Implementation Manual. Washington, DC: The National Academies Press. doi: 10.17226/25364.
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Suggested Citation:"Part B." National Academies of Sciences, Engineering, and Medicine. 2019. Geotechnical Asset Management for Transportation Agencies, Volume 2: Implementation Manual. Washington, DC: The National Academies Press. doi: 10.17226/25364.
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Below is the uncorrected machine-read text of this chapter, intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text of each book. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

Chapter 2 – Starting Geotechnical Asset Management 7 P A R T B Chapter 2 - Starting Geotechnical Asset Management Implementing Geotechnical Asset Management At a most simplistic level, asset management is about managing physical objects with value. Regardless of asset type, once there is even basic knowledge of an asset there is enough information to start asset management. There does not need to be lengthy and time-consuming efforts directed towards manuals, planning, inventory, or data-intensive analysis to start asset management. This comment is not intended to disparage these value-added or process improvement steps in asset management, but rather to remove the perception that starting asset management requires a large and complex investment of time and money, which likely does not exist in most agencies. In fact, most maintenance, technical, and executive level employees in a public-sector infrastructure agency likely perform informal asset management in some form as part of typical duties. This fact is not lost in this GAM implementation process as knowledge of existing problem assets provides an owner with the first step towards prioritizing assets that already suggest a higher risk and are thus excellent candidates for the first assets into an inventory. Therefore, the purpose of this chapter is to enable a geo-professional or any other agency staff member to quickly start implementing geotechnical asset management while also learning the supporting asset management concepts at the same time. The process and accompanying Microsoft Excel software tool (the GAM Planner) in this Chapter will assist an agency in starting risk-based geotechnical asset management around performance objectives related to asset condition, safety impacts, and mobility and economic consequences, which are likely common objectives among many public agencies and thus a simple means of connecting with and gaining support from stakeholders regardless of engagement levels in the process. The outcome of the steps in this chapter will be a simple risk-based GAM inventory and assessment model that can be immediately deployed in decision making while allowing for future inventory additions and model updates by your agency. The remaining Chapters then present background information and optional process improvements that could be incorporated in parallel or after initial implementation to add additional value or agency specific components in GAM. This Chapter will enable an agency to obtain a “quick win” on the path towards integrating into a risk-based transportation asset management program. As a reader progresses through this section, they are encouraged to complete the accompanying steps in the companion Microsoft Excel GAM Planner, if even only for a few initial assets. By following the steps in Chapter 2, GAM implementation will have started by the end of this easy-to-follow chapter. Safety, Mobility and Economic Consequences, and Asset Condition: These are the objectives your GAM plan can easily address.

Chapter 2 – Starting Geotechnical Asset Management 8 Workflow for Implementing GAM The implementation process in this manual is based on the simplified asset management workflow presented in Figure 2-1. Within this workflow, there can be optional, process improvement steps that can be considered at any time and are introduced in Part C of the manual. The goal of this workflow is to enable a quick start to GAM so that benefits can be identified as early as possible, thus generating stakeholder support sooner. Figure 2-1. GAM Implementation Workflow To start the GAM implementation workflow, the manual user should select a corridor or portion of a known inventory to start using the GAM Planner tool. By starting with a few assets (say 10 to 20 assets), the outcomes of the initial workflow loop are easier to digest and understand. Once there is familiarity with the process, models, and inputs, the inventory development will progress more rapidly. Step 1: Identify and Locate Geotechnical Assets Definition of a Geotechnical Asset For this GAM implementation manual, a geotechnical asset is an embankment, slope, retaining wall, or constructed subgrade that contributes to the performance of your transportation system. These assets also

Chapter 2 – Starting Geotechnical Asset Management 9 contribute to the performance of the many culverts, pipes, and utilities that penetrate these engineered structures. Geotechnical components, such as ground reinforcements in a wall or embankment, groundwater drainage features, rock bolts, and structure foundations, are the improvements within many geotechnical or other structure assets that help the asset function through routine loading and extreme events. While there may be a right-of-way (ROW) aspect to defining geotechnical assets for your agency, for this stage of implementation the inventory will focus on compiling the assets first and the consideration of GAM inside or outside of ROW can occur later. A brief review of what defines each geotechnical asset type is presented below. Embankment An embankment asset is a type of geotechnical asset that consists of a constructed fill comprised of rock, soil, or other engineered materials that enables a roadway to maintain a required design elevation above lower lying ground. For this manual, the user is encouraged to use a threshold embankment height of 10 feet (3 m) as delineation between a minor earthwork and an embankment asset, unless there are site conditions such as complex geologic terrain that merit a lower height. Example embankment asset schematics are presented in Figure 2-2. Figure 2-2. Embankment Geotechnical Asset Examples The 10-foot threshold height for an embankment and slope assets is based on more than 15 years of successful implementation experience for 240,000 geotechnical assets on highways and railways throughout the United Kingdom. For more on geotechnical asset and other definitions see the taxonomy discussion in, Chapter 5.

Chapter 2 – Starting Geotechnical Asset Management 10 Slope Slopes are a type of geotechnical asset involving cut excavations that enable a roadway to traverse through surrounding ground with acceptable design profiles. Slopes also may include natural slopes adjacent to a roadway for some agencies. Slopes differ from embankments in that slopes are excavated into terrain rather than a constructed fill feature or may consist of a natural slope that generates a hazard. Slopes can consist of soil, rock, and mixtures of soil and rock as shown in Figure 2-3. Similar to embankment assets, a 10-foot threshold for cut slope height is recommended in the GAM inventory, unless the asset is judged to create an unacceptable hazard to the safety of users and maintenance personnel. Of note, there will be situations where the roadway segment includes both slopes and embankments or other asset types. In these situations, the segment would consist of two assets, one for the slope and one for the embankment. This concept is introduced here and discussed in more detail later in this chapter. Figure 2-3. Geotechnical Slope Asset Examples

Chapter 2 – Starting Geotechnical Asset Management 11 Retaining Walls Retaining walls, or earth retaining structures, are structures that hold back soil and/or rock materials to prevent sliding of material onto a roadway or other structure, or retain material that supports a roadway. This type of geotechnical asset includes retaining walls such as gravity walls, soil nail walls, concrete cantilever structures, or mechanically stabilized earth (MSE) walls. Generally, retaining walls will have vertical or near vertical faces and the recommended threshold inclination is 70 degrees between a wall and an embankment or slope that relies on inclusions for stability. The recommended wall height for incorporation into a GAM inventory is 4 feet, which is based on many examples of what defines a retaining wall in the engineering design process. In many cases, a retaining wall is associated with a bridge structure or approach to a bridge. For the purpose of the inventory process in this implementation manual, if a wall is also a bridge abutment that is integral to the bridge structure, the wall should be considered part of the department bridge inspection and asset management program. All other walls associated with the bridge approaches should be encouraged for incorporation into the GAM plan if not already managed in an asset management program. Examples of retaining wall assets are shown in Figure 2-4 and 2-5. Figure 2-4. Retaining Wall Asset Examples As there is not federal guidance on wall asset management, this manual can be used to quickly incorporate this expanding asset type into the larger TAM program.

Chapter 2 – Starting Geotechnical Asset Management 12 Note: presence of embankment and slope geotechnical assets in the background. Figure 2-5. Geotechnical Explorations on Distressed Wall Asset for Montana Department of Transportation Subgrades Geotechnical subgrade assets are comprised of an earth material below the engineered pavement layers that creates a life-cycle management need. Examples of subgrade assets include constructed earthworks and ground improvements to address swelling, compressible, frozen or thawing ground, or collapsible soil or bedrock or threats from karst (sinkholes) and underground mining. A subgrade asset also may include an unimproved subgrade that presents a measurable hazard from geologic conditions below the roadway. Conceptual views of subgrades are presented in Figure 2-6. Figure 2-6. Example Geotechnical Subgrade Asset Concepts

Chapter 2 – Starting Geotechnical Asset Management 13 Starting Inventory in GAM Planner The simple implementation process in this manual is intended to interface with the companion GAM Planner Tool for inventory, assessment, and investment planning. Within the process of asset management, models are applied to the assets in the inventory to assess future performance and provide guidance for treatment and budget scenarios. When setting up the geotechnical asset inventory, the GAM Planner will require selection of the initial asset performance template for each asset. This is not a difficult process and seven pre-defined default definitions are outlined below. As an agency matures in GAM, new models can be developed and these models can be added to GAM Planner if justified. Additional information on use of the GAM Planner is provided in Appendix A and a companion work example for starting GAM on a hypothetical corridor is provided in Appendix B. Background material for GAM Planner model formulation is provided in Appendix C. Asset Identification When establishing an asset inventory, it is first necessary to identify each geotechnical asset type. Each asset should have a unique asset identification number for reference purposes. A unique asset identification system that distinguishes that asset from other geotechnical assets and transportation assets, such as GA1, GA2, etc. is preferable. Alternatively, other agency specific identifiers can be used if preferred. A simple sequential entry (1, 2, 3, etc.) for assets can be used but may not preferred as the asset inventory is integrated into other agency databases. Asset identification is something that can be easily modified in later stages of implementation. Estimated for Actual Asset Age The age of an asset, if available or estimated, should be included in the asset inventory data collected. While there may be uncertainty in asset age estimates, the data could be useful for certain assets and in future modeling. If the uncertainty is judged unacceptable, this data input can be left blank. Input Model Types Next it is necessary to select the type of geotechnical asset model for each asset. The tool is populated with the default asset type models in Table 2-1 that can enable the inventory and assessment process to start based on generalized performance assumptions. These models and assumptions can be revised later if desired based on judgment and experience of the asset manager. Should this be desired in the future, the GAM Planner can be expanded to 50 different asset type models. Each asset type has its own unique asset model for predicting treatment costs and future conditions.

Chapter 2 – Starting Geotechnical Asset Management 14 Table 2-1. GAM Planner Default Model Types Model Description Asset Category Cut Soil, rock, or mixed cut slopes with a minimum height of 10 feet within the ROW. In general, cut slope assets will have a higher deterioration rate when compared to natural slopes. Slope Asset Natural Hazard – Rock and Debris Natural hazard site that contributes rockfall, debris flows, or other rapid slope movements that may have a safety threat in addition to mobility and maintenance impacts. The deterioration rate associated with this model is assumed to be slower than a cut slope asset and/or or based on recurrence intervals. Slope (Beyond ROW Feature1) Natural Hazard - Landslide Landslide hazard sites that may be included in a GAM inventory. Typically, these assets will consist of natural slides that originate beyond the ROW but impact the agency performance objectives. Slope (Beyond ROW Feature1) Embankment Used for constructed earthwork fills with a minimum height of 10 feet that contribute to the support of a roadway or other transportation assets. Embankment Asset Subgrade Engineered subgrades that have been improved through ground modification/improvement works and support a roadway asset. The subgrade model can also apply to unimproved subgrades with geologic or other subsurface hazards such as expansive or collapsible materials, frost susceptible soil, or karst and underground mining activity. Subgrade Asset Retaining Wall Above Roadway Applicable to retaining walls where the consequences of deterioration or a failure would be confined to at or above the roadway elevation. Retaining Wall Asset Retaining Wall Below Roadway Applicable where a wall supports traffic directly or the deterioration or failure of the wall would have an impact to the roadway integrity or mobility. Retaining Wall Asset 1 Discussion of beyond ROW features in GAM is presented Chapter 5 and considerations for their inclusion in detailed in Chapter 8. Locate Assets Each geotechnical asset in the inventory will have a location and length definition. While location inventory can be a complicated process using various free and proprietary software systems, the inventory process below is intended to be simple, thus removing a potential implementation barrier that results from needing to learn and understand complex and dynamic geo-referencing processes before progressing in GAM. Location The location reference for transportation assets can have different levels of complexity depending on agency data resources, capabilities, technology, and the necessary accuracy for the task at hand. While location precision is valuable in certain applications, a simple GAM implementation can use an existing agency location referencing system such as mile point, mile marker, or reference point as these systems satisfy a desired level of sophistication. The asset manager is cautioned against using a highly precise location method for the asset inventory as there likely is not an offsetting benefit from increased investment in location accuracy.

Chapter 2 – Starting Geotechnical Asset Management 15 As stated earlier, there will often be overlap of geotechnical asset types, as shown in the photograph in Figure 2-5. In this example, a road traversing sloping terrain has a slope asset on the uphill side of the road with both an embankment or wall asset on the downhill side. In this situation, both the slope and embankment should be inventoried as separate assets. GAM Segment Length For this implementation process, the recorded lengths of geotechnical assets will exist independent of the agency referencing system and each asset is inventoried based on a pre-defined length, defined as a segment. When developing your geotechnical asset inventory, the accompanying model is based on a default segment length of 500 feet, or approximately 0.1 mile, which also is similar to pavement condition assessment practices. The GAM Planner user does have the option to change this value if desired. Shorter lengths will result in more assets and complexity, while greater lengths can result in a more granular inventory relative to other asset groups. Each geotechnical asset will be entered in the GAM Planner inventory on the basis of a segment. For individual assets that are longer than one segment, additional segments are added and one can assess the total asset length along the roadway by adding segments together if needed. A conceptual view of the geotechnical asset inventory with segments is provided in Figure 2-7. The recommended procedure for establishing geotechnical asset segments references in a traditional DOT linear referencing system are as follows. • Point or 1-D asset locations are assigned to the nearest mile point (MP) by rounding down such that an asset between MP 92.6 to 92.7, for example, is assigned to a segment designated as MP 92.6. • Laterally extensive assets such as embankments are assigned to each of the roadway segments intersected by the asset. The use of segments is a proven GAM practice that has demonstrated value in established programs in Alaska, Montana, Colorado, and internationally with Network Rail and U.K Highways.

Chapter 2 – Starting Geotechnical Asset Management 16 Figure 2-7. Geotechnical Asset Segment and Location Process The purpose of using the segment concept during inventory will become apparent later in the implementation process, particularly in steps related to communication of results and performance as well as investment planning. Additionally, the segment approach allows the asset manager to consider the aggregated risk from different geotechnical asset types, which also have different geographic characteristics. A view of a hypothetical corridor with multiple asset types is presented in Figure 2-8 to illustrate the concept.

Chapter 2 – Starting Geotechnical Asset Management 17 Figure 2-8. Hypothetical View of a Geotechnical Asset Inventory in Complex Terrain Step 2: Record Asset Operation and Maintenance Condition The next step in creating a geotechnical asset management plan is to estimate the condition for each asset. The template for this step aggregates these methods into a five-level assessment that quantifies condition in terms of visual condition and/or the level of effort to operate and maintain the asset. This is can be measured using the Asset Operation and Maintenance (O&M) Condition decision tree presented in Figure 2-9, which is structured to enable use by a wide range of personnel, including geotechnical staff, bridge inspectors, and planning staff who may have experience with visual condition assessment; or maintenance personnel, who may identify with work effort and needs. For help with understanding how individual assets can be classified in this condition tree, the geotechnical asset assessment photograph examples in Appendix D can be consulted during this process. As background information, decision trees such as Figure 2.9 are commonly used to guide the standardization of inputs into risk assessment practices.

Chapter 2 – Starting Geotechnical Asset Management 18 Figure 2-9. Asset Operation and Maintenance Condition Tree Step 3: Assess Asset Performance Consequences Safety Consequences Part of a risk-based asset management plan is the evaluation of how the asset affects various performance objectives of an agency. As safety is a common objective for transportation departments regardless of asset management maturity levels, the GAM Planner assesses the risk to safety performance objectives from geotechnical assets. The inputs to this process are selected using the following consequence tree in Figure 2-10. Similar to Step 2, Appendix D provides photographic examples of inputs for each safety consequence category.

Chapter 2 – Starting Geotechnical Asset Management 19 Figure 2-10. Safety Consequence Tree for GAM Planner Mobility and Economic Vitality Consequences The GAM Planner enables management of geotechnical assets with respect to mobility objectives, or the economic consequences from delays and closures that result from adverse asset performance. The mobility and economic consequences are assigned in the GAM Planner as shown in Figure 2-11. A key input to mobility consequences is the volume of traffic at the asset location. While inclusion of actual traffic volumes can increase the accuracy of mobility consequence assessment, this also can impede a quick GAM implementation because of challenges with capturing data at each asset, distributions in traffic type, divided roadway effects, detour options, or perceptions of traffic volume scales (e.g., more rural roadways compared to areas with dense populations). Thus, the GAM Planner relies on user judgment to assess the relationship between traffic volume and magnitude of consequence. Should an asset have a potential for a long closure, but be located on a low volume road and/or in an area with detour routes or other options that minimize economic and traffic disruption, the inventory input would select the option that includes “minor economic impacts.” Conversely, if the asset could influence a significant volume of traffic where even a short closure causes significant economic and congestion impacts, the consequence input would select the option with “major economic impacts.”

Chapter 2 – Starting Geotechnical Asset Management 20 Figure 2-11. Mobility and Economic Consequence Tree for GAM Planning Tool Step 4: Review Treatment Recommendations For any asset, there are different life-cycle treatment options that exist. These options can range from a no action alternative to a robust, engineered treatments that are considered a permanent improvement that improves the reliability and extends the service life. The treatment outcomes from the GAM Planner Tool are described below. As indicated earlier, an asset manager can edit the asset type models to revise treatment feasibility, cost, or effects if desired. Appendixes A and C can be reviewed for instructions on how to revise or create new models in the tool. Note the GAM Planner shows the treatment recommended for each asset based on its initial condition. In future inventory improvements, the model can be adjusted or calibrated to the judgment of the user. For example, if actual treatment costs for a given asset are greater or less than that suggested by the model, one can edit the Cost Scale Factor to multiply the predicted treatment cost by a specified factor. These types of activities are recommended in later process improvements after implementation is started. Do Minimum The Do Minimum option consists of essentially performing only the minimum level of work to keep the asset in a condition that allows for traffic conveyance without performing actions that add or preserve life- cycle value. Of note, the Do Minimum option does not correspond to no cost to the asset owner and can be considered a “hands off” management approach that will result in accelerated deterioration and/or service interruptions. Do Minimum actions could involve removing rock and soil from the travel lanes below a slope asset or applying leveling pavement layers to the roadway on an actively moving landslide within an

Chapter 2 – Starting Geotechnical Asset Management 21 embankment asset. Do Minimum actions typically will only occur when a mobility interruption or safety impact has occurred and immediate action is required. Maintain The Maintain treatment category assumes the asset will be maintained in a near continuous operation and maintenance state through planed actions such as those listed below. • Cleaning the roadside ditch below a slope asset that generates rockfall • Managing the vegetation on an embankment or slope asset • Minor earthwork activities to repair an erosion scar in an embankment or slope asset • Cleaning of drainage features on a wall or embankment asset to ensure drainage flow is as designed • Light slope asset scaling activities to reduce specific hazards exposed through erosion • Patching of pavement or other structure cracking associated with geotechnical asset performance • Occasional element replacement (precast blocks) or preservation such as crack sealing or rinsing of accumulated salts on a retaining wall In general, these treatments are regularly frequent but short work activities that may often be considered routine maintenance on an approximate annual basis. The maintain treatments also can be considered preservation work that is needed to fulfill the originally intended service life. The concepts of do minimum and maintain may not be readily understood in some organizations, particularly for geotechnical assets which have not previously been incorporated into defined preservation programs. In general, a Maintain treatment will be performed to enable an asset to deteriorate at a rate that is equal to or better than the originally intended or assumed rate. Rehabilitation (Rehab) A Rehabilitation treatment consists of activities that improve the asset condition to at least the next higher condition level, as shown in Figure 2-9. Work under Rehabilitation can include the following. • Installing groundwater drains or other drainage features into a geotechnical asset with the design intent of reducing likelihood of disruptive movement of the asset • Installation of anchored or draped mesh on a slope asset to reduce the amount of debris reaching the road or catchment ditches • Modifying geometry of an asset or placing buttress fill on a slope to create a more stable condition • Excavating larger catchment ditches, heavy scaling and slope modifications, and/or installing barriers below a slope asset to reduce the potential for rock reaching the roadway travel lane. • Over-excavation and re-compaction of a subgrade asset as part of a pavement rehabilitation project • Replacement or improvement of a significant quantity of deteriorated retaining wall facing elements Typically, Rehabilitation extends the service life through an improved condition.

Chapter 2 – Starting Geotechnical Asset Management 22 Reconstruction Reconstruction treatments consist of actions that result in a significant O&M asset performance improvement to a new or near new condition, effectively resetting the service life. Reconstruction also can be a treatment process to reduce safety and/or mobility consequences in addition to a new service life. Example reconstruction treatments include the following. • Reconstruction of a retaining wall to a current service life-based design standard • Realignment of a roadway to add reliable wall systems and reduce higher deterioration rate assets and/or quantities of slope assets • Reconstructing a distressed embankment or subgrade asset with a reliable engineered fill • Placement of long service life ground reinforcements, such as ground anchors, to stabilize an embankment or slope asset to a high-performance reliability Step 5: Analyzing Impacts of Different Investment Levels Once an asset manager has entered a collection of assets in the inventory, the GAM Planner allows one to evaluate the impact of alternative investment levels. It is important to note that the asset management process will enable better decisions and derive benefits for an organization, even if applying GAM for only a small portion of inventory. Having a limited or small inventory should not be a barrier for GAM. To complete investment analysis using the GAM Planner, one needs to input the expected or proposed budgets by year for the set of geotechnical assets. The GAM Planner shows, given the budget and initial conditions, what costs are expected to be incurred each year, and what the resulting conditions are projected to be for a 10-year planning cycle. The tool includes a detailed result view predicting what will happen over time to a selected asset. One can use these results in addition to the results discussed below as a starting point for prioritizing asset-specific treatment plans. These concepts are expanded in Chapter 8, which presents recommended processes for improving the success potential for GAM implementation, enabling an agency to realize the benefits. The analysis of investment levels is an important step towards the realization of GAM benefits as the outcomes enable an asset manager to demonstrate favorable investment scenarios that help deliver on agency objectives and performance areas. Simply put, the outcomes of the investment analysis can help a geotechnical asset manager “earn a seat at the table” with other asset managers and executives. The GAM Planner analysis provides the opportunity to propose investment strategies for a program of assets and also demonstrate that life-cycle costs will likely increase if sufficient funds are not applied. For example, a hypothetical program may spend $1 million per year on Do Minimum and Maintenance treatments. Should this investment level continue, the longer-term needs may increase to $2 million after five years. However, based on the risk-based GAM Planner assessment, investments of $1.5 million for next 3 years would result in annual funding needs that are reduced to $0.5 million each year. A similar example outcome is presented for the workflow example presented in Appendix B.

Chapter 2 – Starting Geotechnical Asset Management 23 Step 6: Communicate Results Steps 1 to 5 above yield a great deal of valuable information for documenting existing conditions of an organization’s geotechnical assets, quantifying the level of risk these assets pose, and predicting what work should be performed and what conditions will result from a given budget level. The GAM Planner includes various tables and charts that can be used to help communicate results. Key measures and relationships you may wish to use to make the case for needed investments include: • Profile of the existing inventory. Note the O&M Condition and Safety/Mobility Consequence Levels for a given asset are combined into an overall level of risk score and letter grade on an A to F scale for use in summarizing conditions. Discussion of the performance measures for geotechnical assets is presented in Chapter 4. • Predicted investment needs over time for different budget levels. In showing future needs, it can be helpful to show different scenarios at different budget levels. One can readily observe that it is simply not feasible to invest no money in geotechnical assets based on the default model, as the Do Minimum costs and costs of restoring an asset following a failure cannot be avoided. Thus long- term (reactionary) financial needs over time are typically minimized if one budgets sufficient funds for needed maintenance and rehab work. • Predicted distribution of conditions over time. It is often helpful to supplement estimates of investment needs with additional information on condition. Figure 2-12 is an example generated with the GAM Planner showing the predicted distribution of asset conditions over time using the O&M Condition level. Note: higher number and red indicates less favorable conditions. Figure 2-12. Example Distribution of O&M Condition Over Time

Chapter 2 – Starting Geotechnical Asset Management 24 Next Steps The purpose of the preceding discussion is to enable a geo-professional, asset manager, or other engaged agency representative to move a group of geotechnical assets through the spectrum of risk-based GAM. This workflow process can be repeated as the inventory expands and will become easier and more familiar, thus enabling an agency to increase the GAM maturity level. The following Chapters 3 through 7, contain information on the supporting processes and data that align with the practice of TAM and form the foundation of the implementation approach in this manual. Simply having an inventory and models that produces investment plans will probably not be enough to enable successful implementation. This is because the assessment process will likely show investment needs that are well above practical or feasible amounts, which is a common occurrence across even established asset categories such as bridge and pavements. Thus, Chapter 8 contains additional processes and concepts that can help prioritize the GAM implementation for success in different organizational cultures (e.g., your agency). The following processes are offered as suggested next steps, and in no particular order, for continuing the asset management journey. • Expanding inventory • Calibrating the default asset models • Developing new asset models, if needed • Including other agency staff in inventory development • Developing data management program to enable visual graphics of asset characteristics and performance • Authoring a GAM plan document • Adding objectives and measures based on stakeholder feedback • Evaluating the use of other agency-supported software that may offer additional analysis capabilities or compatibility with other TAM databases. The expanded workflow presented in Figure 3-4 contains these steps and other option process improvements that can improve the benefits from GAM.

Next: Part C »
Geotechnical Asset Management for Transportation Agencies, Volume 2: Implementation Manual Get This Book
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TRB's National Cooperative Highway Research Program (NCHRP) Research Report 903: Geotechnical Asset Management for Transportation Agencies, Volume 2: Implementation Manual presents a manual that can be used to implement Geotechnical Asset Management (GAM) planning.

Volume 1, Research Overview, details the scope, process, and findings of the study.

The management of bridge and pavement assets has for many years garnered significant attention by state transportation agencies while the management of geotechnical assets—such as walls, slopes, embankments, and subgrades—has been elusive. Traditionally, geotechnical assets have been treated as unpredictable hazard sites with significant potential liability because failure of any geotechnical asset may lead to traveler delay, damage to other assets, or impact safety. Geotechnical assets are, however, vital to the successful operation of transportation systems and present an opportunity for system owners and operators to realize new economic benefits through risk-based asset management.

There are several downloadable files that accompany Volume 2. Links to those files and the information they contain include the following:

Appendices

Appendix A: Using the GAM Planner,

Appendix B: GAM Inventory Start Example,

Appendix C: GAM Model Formulation,

Appendix D: Geotechnical Asset Condition and Level-of-Risk Examples,

Appendix E: GAM Asset-Level Net Present Value Framework Worksheet,

Appendix F: GAM Plan Outline, and

Appendix G: GAM Implementation Barrier Mitigation Strategy Matrix.

Planner

This file contains the spreadsheet-based (Microsoft Excel) tool. User information for the GAM Planner is provided in Volume 2, Appendix A.

Template

This file contains a spreadsheet-based (Microsoft Excel) worksheet template for a life-cycle cost investment analysis tool. The template supports the process of selecting project-level treatment alternatives in GAM and can be used for investment-based treatment alternative analysis that considers asset or project life-cycle costs including design, O&M, and any potential rehabilitation or reconstruction treatments. User information for the NPV Template appears in Volume 2, Appendix E.

Training Slides

This file contains a slide-based presentation (created in Microsoft PowerPoint) that can be used during training for GAM.Downloadable files and the information contained in those

Note: To use the GAM Planner it is necessary to enable macros. Also, the “Excel Solver” must be installed. The Excel Solver is a plug-in provided with Microsoft Excel.

Software Disclaimer - This software is offered as is, without warranty or promise of support of any kind either expressed or implied. Under no circumstance will the National Academy of Sciences or the Transportation Research Board (collectively "TRB") be liable for any loss or damage caused by the installation or operation of this product. TRB makes no representation or warranty of any kind, expressed or implied, in fact or in law, including without limitation, the warranty of merchantability or the warranty of fitness for a particular purpose, and shall not in any case be liable for any consequential or special damages. TRB's National Cooperative Highway Research Program (NCHRP) Research Report 903: Geotechnical Asset Management for Transportation Agencies provides an introduction and scalable guidance for state transportation agencies on how to implement risk-based geotechnical asset management into current asset management plans. Volume 1, Research Overview, details the scope, process, and findings of the study.

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