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Suggested Citation:"Part B - Starting GAM Implementation." 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 - Starting GAM Implementation." 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 - Starting GAM Implementation." 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 - Starting GAM Implementation." 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 - Starting GAM Implementation." 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 - Starting GAM Implementation." 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 - Starting GAM Implementation." 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 - Starting GAM Implementation." 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 - Starting GAM Implementation." 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 - Starting GAM Implementation." 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 - Starting GAM Implementation." 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 - Starting GAM Implementation." 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 - Starting GAM Implementation." 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 - Starting GAM Implementation." 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 - Starting GAM Implementation." 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 - Starting GAM Implementation." 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 - Starting GAM Implementation." 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 - Starting GAM Implementation." 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.

P A R T B Starting GAM Implementation

11 Implementing GAM At the simplest level, asset management is about managing physical objects with value. Regardless of asset type, even basic knowledge of an asset provides enough information to start asset management. There is no need to direct lengthy, time-consuming efforts to create manuals, conduct extensive planning, develop a detailed inventory, or conduct data-intensive analysis to start asset management. These steps all add value and process improvements as an agency’s GAM process matures, but it is important to remove the perception that starting GAM requires large and complex investments of time and money that may not be available in most agencies. Most maintenance-, technical-, and executive-level employees in a public-sector infrastruc- ture agency likely perform some form of informal asset management as part of their typical duties. Knowledge of existing problems prepares an owner to prioritize assets to create a simple initial inventory for GAM. Assets that already suggest a higher level of risk (LOR) are excel- lent candidates to be included first in the GAM inventory, and the implementation process described in this manual takes advantage of this fact. The purpose of this chapter is to enable a geo-professional or any other agency staff member to quickly start implementing GAM while learning the supporting asset management con- cepts at the same time. The process described, and the accompanying GAM Planner (avail- able online) will assist an agency in starting risk-based GAM based on performance objectives related to asset condition, safety impacts, and mobility and economic consequences. Common across many public agencies, these performance objectives provide a simple means for the agency staff implementing GAM to connect with and gain support from stakeholders at various levels of engagement. Following the steps in this chapter will yield a simple risk-based GAM inventory and assess- ment model. This simple model can be immediately deployed in decision-making while allowing for future inventory additions and model updates based on the agency’s priorities. Thus, this chapter can enable an agency to obtain a “quick win” on the path toward integrating GAM into a risk-based TAM program. The chapters grouped in Part C of the manual present background information and optional process improvements that can be incorporated, either in parallel or following initial implementation of GAM. As they are incorporated into a maturing GAM pro- cess, the added information and process improvements will bring additional value and agency- specific components into the agency’s GAM plan. Readers progressing through this chapter are encouraged to complete the accompanying steps in the companion GAM Planner for a few initial assets. By doing so, GAM implementa- tion will already have started by the end of this easy-to-follow chapter. (The GAM Planner, C H A P T E R 2 Starting GAM GAM can easily address agency objectives related to: • Safety, • Mobility and economic consequences, and • Asset condition.

12 Geotechnical Asset Management for Transportation Agencies, Volume 2: Implementation Manual appendices that include a brief guide to using the GAM Planner, and other online resources are available for download from the NCHRP Research Report 903 web page.) Workflow for Implementing GAM The implementation process described in this chapter is based on the simplified asset man- agement workflow presented in Figure 2.1. Within this workflow, optional process improve- ment steps can be considered at any time. These optional process improvement steps 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. To start the GAM implementation workflow using the GAM Planner tool, the user first selects a corridor (or portion of a known inventory) to identify and locate specific geotechnical assets. By starting with a few assets (e.g., 10 to 20 assets), the outcomes of the initial work flow loop are easier to digest and understand. Once the user gains familiarity with the process, models, and inputs, the inventory development can progress more rapidly. Figure 2.1. GAM implementation workflow.

Starting GAM 13 Step 1: Identify and Locate Geotechnical Assets Definition of a Geotechnical Asset In this GAM Implementation Manual, a geotechnical asset is an embankment, slope, retain- ing wall, or constructed subgrade that contributes to the performance of your transportation system. These assets also contribute to the performance of the many culverts, pipes, and utilities that penetrate these engineered structures. Geotechnical components, such as ground reinforce- ments in a wall or embankment, groundwater drainage features, rock bolts, and structure foun- dations, are the improvements within many geotechnical or other structure assets that help the asset function through routine loading and extreme events. Although an agency’s definition of geotechnical assets may include assets that involve right- of-way (ROW) aspects, it is suggested that during the initial stages of GAM implementation the inventory should focus on compiling the assets, deferring consideration of GAM inside or outside of the ROW to a later step. A brief review of what defines each geotechnical asset type is presented in the following sections. Embankment Assets An embankment asset is a type of geotechnical asset that consists of a constructed fill com- prising rock, soil, or other engineered materials that enables a roadway to maintain a required design elevation above lower-lying ground. This GAM Implementation Manual encourages use of a threshold embankment height of 10 feet (3 m) as delineation between a minor earthwork and an embankment asset, unless existing site conditions (e.g., complex geologic terrain) merit a lower height. Figure 2.2 presents example embankment asset schematics. Slope Assets Slopes are a type of geotechnical asset involving cut excavations that enable a roadway to traverse through surrounding ground with acceptable design profiles. For some agencies, slope For more on the definition of geotechnical asset (and other definitions) see the taxonomy discussion in Part C, Chapter 5. The 10-foot threshold height for embankment and slope assets is based on more than 15 years of success- ful implementation experience for 240,000 geotech- nical assets on high- ways and railways throughout the United Kingdom. Figure 2.2. Embankment geotechnical asset examples.

14 Geotechnical Asset Management for Transportation Agencies, Volume 2: Implementation Manual assets also may include natural slopes adjacent to a roadway. Slopes differ from embankments in that, rather than being constructed fill features, slopes are excavated into terrain or may consist of a natural slope that potentially generates a hazard. Slopes can consist of soil, rock, and mix- tures of soil and rock, as shown in Figure 2.3. Similar to embankment assets, a 10-foot height threshold for cut slopes is recommended in the GAM inventory, unless the asset is judged to create an unacceptable hazard to the safety of users and maintenance personnel. Some roadway segments include both slopes and embankments. In these situations, for purposes of the inventory, the segment consists of two assets: the slope and the embankment. Similarly, if a road segment includes a slope (or embankment) and other assets, each asset is considered separately. This concept is discussed in more detail later in this chapter. Retaining-Wall Assets Retaining walls, or earth-retaining structures, are structures that hold back soil and/or rock materials to prevent material from sliding onto a roadway or other structure, or to retain material in place as needed to support a roadway. This type of geotechnical asset includes gravity walls, soil nail walls, concrete cantilever structures, or mechanically stabilized earth (MSE) walls. 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. Figure 2.3. Geotechnical slope asset examples.

Starting GAM 15 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. Many retaining walls are associated with bridge structures or approaches to a bridge. For the purpose of the inventory process in the GAM 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 agency’s bridge inspection and asset management program. It is encouraged that all other walls associated with the bridge approaches be considered for incorporation into the GAM plan if they are not already managed in another asset management program. Figure 2.4 and Figure 2.5 show examples of retaining-wall assets. Figure 2.4. Retaining-wall asset examples. Note the presence of embankment and slope geotechnical assets in the background. Figure 2.5. Geotechnical explorations on distressed wall asset for Montana DOT.

16 Geotechnical Asset Management for Transportation Agencies, Volume 2: Implementation Manual Subgrade Assets Geotechnical subgrade assets consist of an earth material below the engineered pavement layers that creates a life-cycle management need. Examples of subgrade assets include con- structed earthworks and ground improvements to address: • Swelling; • Compressible, frozen, or thawing ground; • Collapsible soil or bedrock; and/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. Figure 2.6 presents conceptual views of subgrades. Starting Inventory in the GAM Planner The simple implementation process provided in this manual has been designed to interface with the companion GAM Planner for inventory, assessment, and investment planning. Within the process of asset management, models are applied to the assets that are included in the inventory. The models allow the GAM Planner to project future performance and provide guidance for possible treatment and budget scenarios. When setting up the geotechnical asset inventory in the GAM Planner, the user must select an initial asset performance template for each asset. This process is not difficult, and the tool provides seven pre-defined default definitions. As an agency’s use of GAM matures, new and more refined models can be developed and added to the GAM Planner if justified. Additional information on using the GAM Planner is provided in Appendix A, and a companion work example for starting GAM using a hypothetical corridor is provided in Appendix B. Background material to assist GAM Planner model formulation is provided in Appendix C. Figure 2.6. Example geotechnical subgrade asset concepts.

Starting GAM 17 Asset Identification When establishing an asset inventory, it is first necessary to identify each geotechnical asset type. Each asset will need to be assigned a unique asset identification number (e.g., GA1, GA2) for reference purposes. An asset identification system that can assign unique numbers and dis- tinguish each asset from any other geotechnical and transportation asset is preferable. Alterna- tively, other agency-specific identifiers can be used. It is possible to begin GAM implementation using a simple sequential entry (e.g., 1, 2, 3) for each asset, but this system is not preferred because it may be difficult to integrate into other agency databases. Asset identification can be modified during later stages of implementation. Asset Age (Estimated or Actual) The age of an asset, either actual (if available) or estimated, should be included in the asset inventory. Even though estimates of asset age contain uncertainties, the data can be useful for certain assets and in future modeling. If the level of uncertainty is judged to be unacceptable, this data input can be left blank in the GAM Planner. Input Models Based on Asset Type In the GAM Planner, each asset type has a unique model for predicting treatment costs and future conditions. The spreadsheet tool is populated with several default models, as shown in Table 2.1. For each geotechnical asset in the inventory, the user must select the model that will be applied. The default models enable the inventory and assessment process to start based on generalized performance assumptions, but the models and assumptions can be revised later Model Description Asset Type 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 sites that contribute rockfall, debris flows, or other rapid slope movements that may pose a safety threat in addition to mobility and maintenance impacts. The deterioration rate associated with this model is assumed to be slower than that for a cut-slope asset or based on recurrence intervals. Slope Asset (Beyond-the- ROW Feature*) 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’s performance objectives. Slope Asset (Beyond-the- ROW Feature*) 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 locations at or above the roadway elevation. Retaining-Wall Asset Retaining Wall Below Roadway Applicable if a wall supports traffic directly or if the deterioration or failure of the wall would impact the roadway integrity or mobility. Retaining-Wall Asset *Discussion of beyond-the-ROW features in GAM is presented Chapter 5 and considerations for their inclusion are detailed in Chapter 8 of this GAM Implementation Manual. Table 2.1. Default models based on asset type as used in the GAM Planner.

18 Geotechnical Asset Management for Transportation Agencies, Volume 2: Implementation Manual based on the judgment and experience of the asset manager. If desired, the GAM Planner can be expanded to incorporate up to 50 distinct asset-type models. Locate Assets Each geotechnical asset specified in the GAM Planner inventory will have a unique location and a defined length. Although location inventory can be a complicated process using various free and proprietary software systems, the inventory process described in this manual is intended to be simple, thus removing a potential barrier to implementation that could result from need- ing to learn and understand complex and dynamic geo-referencing processes before progressing in GAM. Location The location references assigned to transportation assets can have differing levels of com- plexity depending on agency data resources, capabilities, technology, and the level of accu- racy needed for the task at hand. Location precision is valuable for certain applications, but a simple GAM implementation can use existing agency location referencing (e.g., mile point, mile marker, or reference point), as these systems generally satisfy a desired level of sophistication. The asset manager is cautioned against investing time and resources to use a highly precise loca- tion method for the asset inventory because the offsetting benefits will likely be minimal. Geotechnical asset types often overlap. The photograph in Figure 2.5 shows one example, in which a road traverses sloping terrain. A slope asset can be seen on the uphill side of the road, and both an embankment asset and a wall asset are visible on the downhill side. In this situation, the slope, the wall asset, and the embankment should be inventoried as separate assets. GAM Segment Length For purposes of the implementation process embedded in the GAM Planner, the recorded lengths of geotechnical assets are considered independent of an agency’s referencing system, and each asset is inventoried based on a pre-defined length, defined as a segment. As users’ experience with GAM planning matures, the defaults established in the GAM Planner can be customized as desired to reflect the agency’s specific referencing system and measurements. For example, when developing the initial geotechnical asset inventory, the accompanying model is based on a default segment length of 500 feet (approximately 0.1 mile), which is simi- lar to the measurements used for pavement condition assessment practices. Users of the GAM Planner have the option to change this value if desired. Shorter lengths will result in more assets and complexity, whereas 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 seg- ment. For individual assets that are longer than one segment, additional segments are added and the user can assess the total asset length along the roadway by adding segments together if needed. The recommended procedures for establishing geotechnical asset segment references in a traditional DOT linear referencing system are: • Point (also called one-dimensional, or 1-D) asset locations are assigned to the nearest mile point (MP) by rounding down (e.g., an asset falling between MP 92.6 and MP 92.7 would be assigned to a segment designated as MP 92.6); and • Laterally extensive assets are assigned to each of the roadway segments intersected by the asset (e.g., an embankment that intersects two roadway segments would be assigned to both the roadway segments). Figure 2.7 provides a conceptual view of the geotechnical asset inventory with segments. 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 UK Highways.

Starting GAM 19 The purpose of using the segment concept during input of the inventory will become appar- ent later in the implementation process, particularly in the steps related to communicating results and performance, and those related to investment planning. The segment approach also allows the asset manager to consider the aggregated risk from various geotechnical asset types that have differing geographic characteristics. Figure 2.8 illustrates this concept using a view of a hypothetical corridor with multiple asset types. Step 2: Record Asset Operations and Maintenance (O&M) Conditions The next step in creating a GAM plan is to record the available information about the current condition of each asset. In the GAM Planner, the template for this step aggregates the methods used to estimate asset condition into a five-level assessment that quantifies asset condition in terms of (1) visual condition and/or (2) the level of effort needed to operate and maintain the asset. Each asset is assigned to one of the five levels using the Asset Operations and Mainte- nance (O&M) Condition decision tree. Presented in Figure 2.9, this decision tree 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 per- sonnel (who may identify more closely with operational and maintenance needs). Geotechnical Figure 2.7. Geotechnical asset segment and location process.

20 Geotechnical Asset Management for Transportation Agencies, Volume 2: Implementation Manual Figure 2.9. Asset O&M condition decision tree. Figure 2.8. Hypothetical view of a geotechnical asset inventory in complex terrain.

Starting GAM 21 asset assessment photographs have been provided in Appendix D (available online) to help with understanding how individual assets can be classified using the decision tree. As background information, decision trees such as the one shown in Figure 2.9 are commonly used to guide the standardization of inputs in risk assessment practices. 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 depart- ments 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 consequence tree shown in Figure 2.10. The photographic examples in Appendix D again provide examples of inputs for each safety consequence category. Mobility and Economic Vitality Consequences The GAM Planner enables management of geotechnical assets with respect to mobility objec- tives and the economic consequences from delays and closures that result from adverse asset performance. The mobility and economic consequences are assigned in the GAM Planner fol- lowing the decision tree shown in Figure 2.11. A key input to mobility consequences is the volume of traffic at the asset location. Inclusion of actual traffic volumes can increase the accuracy of mobility consequence assessment, but a quick GAM implementation can be impeded by the challenges of capturing data at each asset, including distributions in traffic type, divided roadway effects, detour options, or perceptions of traffic volume scales (e.g., roadways in areas that are more rural compared to areas with dense populations). Thus, the GAM Planner relies on user judgment to assess the relationship Figure 2.10. Safety consequence decision tree for the GAM Planner.

22 Geotechnical Asset Management for Transportation Agencies, Volume 2: Implementation Manual between traffic volume and magnitude of consequence. As an example, for an asset that has potential for a long closure but is located on a low-volume road and/or in an area with detour routes or other options that minimize economic and traffic disruption, the asset manager can select the inventory input option that includes “minor economic impacts.” Conversely, if the asset could influence a significant volume of traffic such that even a short closure would cause significant economic and congestion impacts, the asset manager can select the consequence input option with “major economic impacts.” Step 4: Review Treatment Recommendations For any asset, various life-cycle treatment options exist. These options can range from a “no action” alternative to robust, engineered treatments that are considered a permanent improve- ment that improves the reliability of the asset and extends its service life. This section of the GAM Implementation Manual describes the treatment outcomes from the GAM Planner. As the asset manager gains experience with GAM, the manager can edit these preset asset-type models to revise treatment feasibility, cost, or effects as desired. Appendixes A and C to this manual (available online) provide instructions for revising or creating new models in the GAM Planner. The GAM Planner shows the treatment recommended for each asset based on its initial condition. The model can be adjusted or calibrated to the judgment of the user when future inventory adjustments or improvements are made. For example, if actual treatment costs for a given asset are greater or less than those suggested by the model, the user can edit the Cost Figure 2.11. Mobility and economic consequence decision tree for the GAM Planner.

Starting GAM 23 Scale Factor to multiply the predicted treatment cost by a specified factor. It is recommended that these types of adjustments take place as part of later process improvements after GAM implementation has started. Do Minimum The “Do Minimum” option consists of performing only the minimum level of work needed to keep the asset in a condition that allows for traffic conveyance without performing actions that add or preserve life-cycle value. The Do Minimum option does not correspond to no cost to the asset owner. It 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 embankment asset. Do Mini- mum actions typically occur only when a mobility interruption or safety impact has occurred and requires immediate action. Maintain The “Maintain” treatment category assumes the asset will be maintained in nearly continuous O&M state through planned actions such as: • 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 that 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 perfor- mance; or • Occasional element replacement (e.g., precast blocks) or preservation tasks such as crack sealing or rinsing of accumulated salts on a retaining wall. In general, these treatments are regular, frequent, but short work activities that often may be considered routine maintenance on an approximate annual basis. These treatments also can be considered preservation work that is conducted needed to help the asset fulfill the originally intended service life. In other words, 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 deteriora- tion rate. Particularly in relation to geotechnical assets, the concepts of Do Minimum and Maintain may be unfamiliar in some organizations because these assets have not previously been incor- porated into defined preservation programs. Rehabilitate (Rehab) In the GAM Planner, the “Rehabilitate (Rehab)” treatment category refers to rehabilitation activities that will improve the asset condition to at least the next higher condition level. Rehab work can include: • Installing groundwater drains or other drainage features into a geotechnical asset with the design intent of reducing likelihood of disruptive movement of the asset; • Installing anchored or draped mesh on a slope asset to reduce the amount of debris reaching the road or catchment ditches;

24 Geotechnical Asset Management for Transportation Agencies, Volume 2: Implementation Manual • Modifying the 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-excavating and re-compacting a subgrade asset as part of a pavement rehabilitation project; or • Replacing or improving a significant quantity of deteriorated retaining wall facing elements. Typically, rehabilitation treatments extend the asset’s service life through an improved condition. Reconstruct (or Renew) Treatments in the “Reconstruct (or Renew)” category will consist of actions that result in a significant O&M asset performance improvement to a new or nearly new condition, effectively resetting the asset’s service life. Reconstruction also can refer to treatment processes designed to reduce safety and/or mobility consequences in addition to extending the asset’s service life. Examples of reconstruction treatments include: • Reconstructing a retaining wall to meet the design standard for a “current” service life; • Realigning a roadway to add reliable wall systems and reduce the deterioration rate of assets and/or the quantities of slope assets; • Reconstructing a distressed embankment or subgrade asset with a reliable engineered fill; and • Placing ground reinforcements with long service lives (e.g., ground anchors) to stabilize an embankment or slope asset to a high-performance reliability. Restore In the GAM Planner, the model triggers a treatment action called “Restore” if an asset fails (reaches an O&M Condition level of 5). The user sets parameters to define what constitutes fail- ure for the given asset type, specifies the agency and user costs of this treatment, and defines the resulting condition on completion of the treatment. As defined in the GAM Planner, restoration differs from reconstruction or renewal in that the Restore treatment is undertaken only upon failure of the asset. By contrast, Reconstruct (or Renew) treatments are used to improve asset performance and/or extend the asset’s service life before it reaches operational failure. Step 5: Analyze the Impacts of Differing Investment Levels Once a collection of assets has been entered in the inventory, the GAM Planner allows an asset manager 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 GAM is applied only to a small portion of inventory. Having a limited or small inventory should not be a barrier to implementing GAM; rather, beginning with a small inventory may facilitate broader adoption because it allows the asset manager to demonstrate the utility and benefits of GAM. To complete the investment analysis using the GAM Planner, the user will need to input the expected or proposed budgets by year for the set of geotechnical assets that have been included in the inventory. Given the budgets and initial conditions, the GAM Planner then calculates what costs are expected to be incurred each year, and projects the resulting conditions for a 10-year planning cycle. The detailed “Summary Results” view in the spreadsheet tool predicts what will happen over time to a selected asset. The Summary Results can then be used as a starting

Starting GAM 25 point for prioritizing or modifying asset-specific treatment plans. These concepts are expanded in Chapter 8 of this manual, which presents recommended processes for improving the success potential of GAM implementation, enabling an agency to realize the benefits. Analyzing investment levels is an important step toward the realization of GAM benefits. Using the GAM Planner, the outcomes shown in the Summary Results enable an asset manager to demonstrate favorable investment scenarios that can help deliver on agency objectives and performance areas. Simply put, the outcomes of the investment analysis can help a geo technical 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 to demonstrate that life-cycle costs will likely increase if sufficient funds are not applied. Consider a hypothetical asset management program that spends $1 million per year on Do Minimum and Maintain treatments. Should this investment level continue, longer-term needs will likely increase to $2 million each year after 5 years. Using the risk-based GAM Plan- ner assessment, it might be shown that increasing the agency’s investments to $1.5 million for the next 3 years (Year 2 through Year 4) would reduce the annual funding needs to $0.5 million each year after Year 5, and that the additional investment of $1.5 million over those 3 years could result in a net savings to the agency of $6 million by the end of 10 years. The workflow example provided in Appendix B shows a similar outcome. Step 6: Communicate Results Steps 1 to 5 yield a great deal of valuable information for documenting the existing condi- tions of an organization’s geotechnical assets, quantifying the assets’ LOR, and predicting what work should be performed and what conditions will result from a given investment (budget) level. The GAM Planner includes various tables and charts that can be used to help commu- nicate results. Key measures and relationships the asset manager may wish to use to make the case for needed investments include: • Profile of the Existing Inventory: In the GAM Planner, the O&M condition and safety/ mobility consequence levels for a given asset are combined into an overall score for the LOR, which is given a letter grade from A to F for use in summarizing conditions. A more detailed discussion of the performance measures for geotechnical assets is presented in Chapter 4 of this manual. • Predicted Investment Needs Over Time for Differing Budget Levels: When considering future needs, it can be helpful to show a variety of scenarios based on differing budget levels. The default model easily demonstrates that it is simply not feasible to invest no money in geotechnical assets, as the Do Minimum costs and costs to Restore an asset following a failure cannot be avoided. Moreover, the long-term (reactionary) financial needs over time are typi- cally minimized if the asset manager budgets sufficient funds to Maintain and, as needed, to Rehab the assets. • Predicted Distribution of Conditions Over Time: Often it is helpful to supplement esti- mates of investment needs with additional information on asset condition. Figure 2.12 is an example generated using the GAM Planner that shows the predicted distribution of asset conditions over time using the O&M condition level. Next Steps The discussion of Steps 1 through 6 has been provided to enable a geo-professional, asset manager, or other engaged agency representative to move a group of geotechnical assets through the process of risk-based GAM. This workflow process can be repeated and modified as the

26 Geotechnical Asset Management for Transportation Agencies, Volume 2: Implementation Manual inventory expands, and as GAM becomes easier and more familiar, thus enabling an agency to increase its GAM maturity level. Chapters 3 through 7 in this GAM Implementation Manual present information on the supporting processes and data that align GAM with the existing practice of TAM and that form the foundation of the implementation approach. Simply having an inventory and models that produce investment plans will probably not be enough to enable successful GAM implementation. The assessment process will likely reveal investment needs that are well above practical or feasible amounts, which is a common occur- rence across even established asset categories such as bridge and pavements. Chapter 8 contains information about additional processes and concepts that can help asset managers priori- tize the GAM implementation for success in differing organizational cultures (i.e., a variety of agencies). These processes are offered as suggested next steps, to be taken 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 a 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; and • Evaluating the use of other agency-supported software that may offer additional analysis capabilities or compatibility with other TAM databases. Presented near the end of Chapter 3, Figure 3.4 summarizes an expanded workflow that incor- porates these steps and other optional process improvements that can improve the benefits an agency receives from GAM. 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% 1 2 3 4 5 6 7 8 9 10 Pe rc en t o f I nv en to ry Year 5 4 3 2 1 Note: Higher number and red (darkest) color indicate less favorable conditions. Figure 2.12. Example distribution of O&M condition over time.

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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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