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From page 251... ... 251 A A P P E N D I X A Geotechnical Instrumentation A.1 Purpose of Geotechnical Instrumentation Geotechnical instruments can be used in transportation projects before, during, and after construction and can play an important role in providing real-time or near real-time information on the health and serviceability of transportation infrastructure. Such information can be used to monitor the behavior or performance of structures and can be incorporated into an early warning system. Read the entire page →
From page 252... ... 252 with the performance of geotechnical structures. This section describes basic types of instruments and how they can be used to measure the parameters identified above. Read the entire page →
From page 253... ... 253 Table A-1. Attributes of several instruments available for measuring deformation Instrument Application Advantages Disadvantages Comments Settlement Plate and Survey Marker Measures the settlement of soft ground under embankments Relatively inexpensive Requires regular visits by a surveyor, automation process is expensive, accuracy depends on the operator, and equipment is susceptible to damage by construction equipment. Read the entire page →
From page 254... ... 254 Instrument Application Advantages Disadvantages Comments Horizontal Inclinometers and Settlement Profilers Measures settlement or heave Relatively inexpensive and can acquire large amount of data Potential for leaks if hydraulic system is used, potential collapse of the casing under embankment load (durability) Read the entire page →
From page 255... ... 255 instruments available to measure loads and pressures. In addition to the instruments listed in Table A-2, strain gauges attached to the soil reinforcement elements (e.g., soil nails, anchors) Read the entire page →
From page 256... ... 256 Instruments Applications Advantages Disadvantages Comments Accelerometers Measures ground acceleration Very accurate measurements of strong and weak signals even in the presence of noise More expensive than geophones. Uses MEMS sensors. Read the entire page →
From page 257... ... 257 Table A-4. Steps of instrumentation system design Steps Considerations Planning Project conditions • Anticipated project risks and objectives of the monitoring • Failure mechanisms or hazards resulting in the risks (e.g., variations in water table, settlement, deflection) Read the entire page →
From page 258... ... 258 Steps Considerations Instrumentation Plan Instrument layout (type, quantity, and location) • Select instrument types that measure relevant geotechnical parameters, with appropriate range, sensitivity, and accuracy. Read the entire page →
From page 259... ... 259 Steps Considerations System Cost • Include the cost of equipment; monitoring for the entire duration, maintenance, repairs, and spare instruments to replace damaged units. • Evaluate the cost comparison between manual and automated monitoring systems with respect to frequency of monitoring. Read the entire page →
From page 260... ... 260 There are, however, several limitations to using automated data collection: • Increased upfront cost • Potentially increased total cost • Increased complexity of system • Increased difficulty of installation A.5.2 Data Loggers A data logger is an electronic device that collects, analyzes, and stores data from sensors. A data logger can be connected to one or more sensors, usually through external cables. Read the entire page →
From page 261... ... 261 wired or wireless, a user can either manually connect to the computer and download the data or set up a program to automatically connect to the data logger regularly to download the data. A.5.4 Data Storage Data must be stored after being collected. Read the entire page →
From page 262... ... 262 A.6.4 Data Reporting At a predetermined frequency, the collected data should be presented and summarized in a data report. This data report can communicate the results of the instrumentation monitoring to all project stakeholders. Read the entire page →
From page 263... ... 263 References Bartholomew, C.L., B.C. Murray, and D.L. Read the entire page →
From page 264... ... 264 B A P P E N D I X B Applications of Geotechnical Instrumentation B.1 Introduction Geotechnical instrumentation applications transcend all phases of a transportation project's life cycle. Geotechnical instrumentation data collected during the preconstruction phase contributes to the design of safe and economical geotechnical infrastructure. Read the entire page →
From page 265... ... 265 Source: Geosyntec Consultants, Inc. Figure B-1. Read the entire page →
From page 266... ... 266 7. Change in pore pressure around the excavation area Measuring these parameters provides information pertaining to the following: 1. Read the entire page →
From page 267... ... 267 B.5 Earth-Retaining Structures Earth-retaining structures (e.g., braced excavations, mechanically stabilized earth walls, soil nail walls) are commonly used as a part of excavation or embankment construction. Read the entire page →
From page 268... ... 268 Source: Geosyntec Consultants, Inc. Figure B-4. Read the entire page →
From page 269... ... 269 Various instrumentation systems (e.g., surveying equipment, borehole extensometers, tilt meters, crack meters, strain gauges, piezometers, inclinometers) can be used to monitor the performance of tunnels during construction. Read the entire page →
From page 270... ... 270 predict the long-term performance of the geotechnical structures, and (iii) identify structures with impending higher risks of failure or deficient performance. Read the entire page →
From page 271... ... 271 References FHWA. Read the entire page →
From page 272... ... 272 C A P P E N D I X C Evaluation of Existing Bridge Foundations for Reuse C.1 Introduction Reuse of existing bridge foundations has attracted the attention of State Departments of Transportation (DOTs) because of the potential for savings in construction time, direct construction costs, and indirect costs, such as road user costs. Read the entire page →
From page 273... ... 273 • Biennial bridge inspection reports that the Federal Highway Administration (FHWA) requires State DOTs to perform • Bridge maintenance history • Monitoring reports (e.g., for bridge scour) Read the entire page →
From page 274... ... 274 Figure C-1. SE/IR test setup C.2.2.2 Dispersive Flexural Wave Test The dispersive flexural wave test is performed on driven concrete and timber piles, drilled piers, and auger-cast piles in situations where the top surface of a foundation element is not accessible. Read the entire page →
From page 275... ... 275 the concrete, and measuring the voltage difference (Figure C-3) Read the entire page →
From page 276... ... 276 Source: after Wightman et al. Read the entire page →
From page 277... ... 277 C.3 Information Needed to Evaluate Load-Carrying Capacity The following information is required to evaluate the load-carrying capacity of bridge foundation elements: • Geometric properties of the foundation element (shape, cross section area, and length) • Structural properties of the deep foundation element (e.g. Read the entire page →
From page 278... ... 278 C.3.2 Geophysical Testing Methods Nondestructive geophysical tests are primarily used to estimate the lengths of the deep foundation elements. The following are some of the more common geophysical tests performed: • SE/IR • Dispersive flexural wave • Ultraseismic profiling • Induction field method • Parallel seismic method Information pertaining to the SE/IR, dispersive flexural wave, and the ultraseismic testing methods is presented in Section C.2.2. Read the entire page →
From page 279... ... 279 Source: after Wightman et al. Read the entire page →
From page 280... ... 280 C.3.3 Characterizing Foundation Materials Evaluating existing bridge foundations for reuse requires the same types of material parameters as needed for characterizing foundation materials for the design of new bridge foundations. Therefore, the methods and procedures presented in Chapters 5 through 8 for new bridge projects are also applicable to evaluating existing bridge foundations. Read the entire page →
From page 281... ... 281 References Collin, J.G., and F Jalinoos, 2014. Read the entire page →
From page 282... ... 282 D A P P E N D I X D Management of Geotechnical Data D.1 Introduction In large measure, historical information from transportation projects is documented on paper and maintained in project files. But, with the explosive growth of computer usage in engineering, most information is now being collected and maintained electronically, which should make the information easier to collect, manage, and use on future projects. Read the entire page →
From page 283... ... 283 the original electronic data was maintained in a format that allows users to readily access the original data they need. This efficient access of original data can be accomplished by using a database to store and retrieve the data. Read the entire page →
From page 284... ... 284 data are collected in a consistent, standard manner, thus minimizing the opportunities for introducing human error. Another technique to facilitate data management is to adopt a standard data transfer protocol. Read the entire page →
From page 285... ... 285 4. Spatial consistency of every data entry 5. Read the entire page →
From page 286... ... 286 nonproprietary data software program of the owner's discretion. In this way, it is explicitly required as part of the project specifications that the entity generating and hosting the project data recognizes the rules for working on the project. Read the entire page →
From page 287... ... 287 Data Organization Data organization acknowledges the concept that all data ultimately must be recovered and used in some manner. Therefore, it is imperative to input data in a consistent format and in a specific location in the database. Read the entire page →
From page 288... ... 288 Field Type Key Required Relationship Example Description Group Text(40) CA 1 User-defined grouping of locations (e.g., critical area, line ID, etc.) Read the entire page →
From page 289... ... 289 specific test results at a specific borehole. Because there may be multiple records that describe these activities, it will be necessary to keep track of the previous 20 columns for every data record, so that the data are appropriately referenced and associated with the correct project and drilling activity. Read the entire page →
From page 290... ... 290 D.2.3 Data Collection Once the commitment is made to manage data instead of managing information, the user should contemplate the best procedures for collecting the requisite data for a project. Following one of the basic tenets of effective data management, collecting and recording data need only be done once. Read the entire page →
From page 291... ... 291 development of new skills. Specifically, personnel will likely must learn new computer skills that require computer coding strategies to facilitate the evolution. Read the entire page →
From page 292... ... 292 the project (often an arbitrary reference to 0+00) reference along a project centerline and offset left or right from the centerline. Read the entire page →
From page 293... ... 293 Table D-1. Example of Project Metadata TableName SourceDatabase ObjectType Description Author vXs_PlanesExport /Features Shapefile Lines in plan view at GDOT provided Station R Read the entire page →
From page 294... ... 294 validated form, it is possible to develop reports, data summary tables, and plots directly from the database. This section will provide an introduction on the end use of the data. Read the entire page →
From page 295... ... 295 User Considerations A critical component of the project work flow relates to the role of the various users of the data management system. As shown on the left side of Figure D-3, the user may be engaged in the earliest stage of data collection, as they may be responsible for populating the forms-based template. Read the entire page →
From page 296... ... 296 D.3.3 Data Validation Just because data are collected and recorded, does not mean that the data are always 100 percent correct. Errors could be due to transposing numbers or placing data in an incorrect field. Read the entire page →
From page 297... ... 297 the big advantages to adopting more efficient techniques for data management. Therefore, it is strongly recommended that data visualization strategies be considered with an end-user interface in mind in the early stages of project database development. Read the entire page →
From page 298... ... 298 solutions, there may be limited options when using proprietary database programs, primarily because these software vendors have a commercial interest in limiting the options that users have. Again, this practice is highly discouraged and when presented with this option, the user should simply decline and look for other more sustainable solutions. Read the entire page →
From page 299... ... 299 The disadvantages include the lack of documentation and product support, although a community of like-minded users generally avail themselves to help support the product. The primary disadvantage, however, is that the longevity of the product is not guaranteed, so the user will likely must be computer savvy and have the ability to code as needed to maintain the program and to increase functionality. Read the entire page →
From page 300... ... 300 capability and functionality of the database should be ensured. An SQL-based database is often selected because of its demonstrated ability to function in this capacity. Read the entire page →
From page 301... ... 301 offering commercial packages includes (i) Bentley, (ii) Read the entire page →
From page 302... ... 302 Geotechnical laboratory data would be the next most logical candidate for the database. Once these data are captured and assessed, State and regional characterization assessment could be readily performed. Read the entire page →
From page 303... ... 303 Performance Monitoring Information The geotechnical instrumentation that may be used during site investigation or during construction are often left in place to monitor performance after construction is complete. If these records are provided in the database, then performance can be associated with specific geotechnical condition, construction difficulties, geohazards, or other events. Read the entire page →
From page 304... ... 304 database can be viewed as a tremendous resource to researchers. This is yet another positive attribute and benefit that comes from a commitment to manage geotechnical data. Read the entire page →
From page 305... ... 305 focused primarily of geotechnical data. Having access to this information in a common reference system, will likely prove valuable to the geotechnical project. Read the entire page →
From page 306... ... 306 Data Analysis Historically, geoprofessionals have dedicated much of the allocated time for the project to collect and compile the data, resulting in less-than-desired time for data analysis. If the data collection and compilation efforts can be streamlined, then there should be time available for analysis of the data. Read the entire page →
From page 307... ... 307 Data Integration with Other Technical Units Within the agency organization, there are other technical units, including hydraulics, pavements, and structures, that have a need for geotechnical data. The geotechnical database can also store, manage, or reference geotechnical information that are related to the project success. Read the entire page →
From page 308... ... 308 demonstrated in Figure D-4. If users understand the DIGGS schema and the associated rules for identifying attributes of the schema, then any data can be converted into a valid DIGGS file. Read the entire page →
From page 309... ... 309 Tools to Facilitate Data Input, Output, and Exchange The DIGGS developers are working to develop tools that can be used to facilitate data input, output, and interchange. These tools will be posted on the DIGGS and G-I website to promote use of the DIGGS standard, at least until software developers (either commercial or open-source) Read the entire page →
From page 310... ... 310 E A P P E N D I X E Quality Assurance Systems E.1 Introduction Quality assurance (QA) systems consist of processes that evaluate and monitor a product or service to ensure compliance with established norms or standards. Read the entire page →
From page 311... ... 311 Additional information and guidance to develop a QA system can be obtained from the U.S. Office of Personal Management (USOPM) Read the entire page →
From page 312... ... 312 E.2.3 Quality Assurance/Quality Control Policy The QA/QC policy is the State DOT policy statement to obtain geotechnical services that meet the state and federal acceptable levels of quality and consistency. E.2.4 Roles and Responsibilities The roles and responsibility of the State DOT upper management, project managers or supervisors, and geotechnical personnel are defined with respect to implementing the QA plan. Read the entire page →
From page 313... ... 313 • Handling samples • Selecting test specimens • Calibrating equipment • Specifying and referencing laboratory testing standards and manuals The QA/QC plan should standardize the format of conducting and reporting all laboratory testing and type of deliverables to maintain consistency and facilitate the evaluation of quality. E.2.5.3 Instrumentation The instrumentation QA/QC plan requirements should distinguish between the distinct types of geotechnical instrumentation programs. Read the entire page →
From page 314... ... 314 E.2.6.2 Laboratory Testing Laboratory testing services can be prequalified by using the AASHTO Materials Reference Laboratory (AMRL) certification program for specific laboratory tests using either the AASHTO or ASTM laboratory standards or as required by the State DOT. Read the entire page →
From page 315... ... 315 Many State DOTs have specialized laboratory testing standards that either modify existing nationally recognized standards or have laboratory testing procedures that have been developed specifically for the State DOT's use. These specialized laboratory testing procedures must be formally documented by developing an in-house standard testing procedure. Read the entire page →
From page 316... ... 316 References CALTRANS. Read the entire page →
From page 317... ... 317 F A P P E N D I X F Health and Safety F.1 Introduction Improper and unmanaged fieldwork activities during a geotechnical site investigation program may pose risks to human health and safety. For example, working around heavy equipment, such as drill rigs and cone penetration testing rigs, contains safety risks. Read the entire page →
From page 318... ... 318 F.4 Site Investigation Permit Before any investigation can begin, the proper permits need to be obtained, where applicable. State and local regulations may require subsurface drilling permits. Read the entire page →
From page 319... ... 319 • Are there visible repaved asphalt or concrete patches, trenches, or other road cuts? If location is in an unpaved area, is there any displaced grass or dirt, or evidence of recent digging? Read the entire page →
From page 320... ... 320 • To the extent practical, mechanical or powered equipment will be used to handle, lift, or move heavy objects weighing more than 49 lbs. Manual handling of heavy objects shall be kept to a minimum. Read the entire page →
From page 321... ... 321 F.7.4 Task Hazard Analysis A task hazard analysis is a technique that focuses on job tasks to identify hazards before they occur. It focuses on the relationship between the worker, the task, the tools, and the work environment and includes the following: • A description of the site and its current condition • A description of the tasks and operations that will be performed at the site • The chemical, physical (e.g., heat and cold stress, fire, traffic, rain, lightning) Read the entire page →
From page 322... ... 322 F.7.4.2 Manual Materials Handling Handling materials manually can be hazardous, and those hazards are increased if personnel do not follow the right precautions. The following are a list of procedures that personnel should follow to reduce the risk of injury while manually handling materials: • Use proper lifting techniques. Read the entire page →
From page 323... ... 323 exceed those requirements set forth in 1910.120. Additional medical monitoring and training may be required based on site activities. Read the entire page →
From page 324... ... 324 to allow field personnel to loosen or remove protective clothing, and sufficient seating should be available for all field personnel. During breaks, field personnel must be encouraged to drink plenty of water or other liquids, even if not thirsty, to replace lost fluids and to help cool off. Read the entire page →
From page 325... ... 325 F.7.4.6 Rain and Lightning Adverse weather conditions, such as rain and lightning, present hazards to the job site. These hazards can include reduced visibility, slippery surfaces, and even being struck by lightning. Read the entire page →
From page 326... ... 326 F.7.4.8 Biological Hazards Biological hazards include insects, spiders, ticks, rodents and wild or stray animals, snakes, and poisonous plants. • Insects, spiders, and ticks – Protect yourself from biting and stinging insects by wearing long pants, socks, and long-sleeved shirts. Read the entire page →
From page 327... ... 327 F.7.5 Evacuation Plan An evacuation plan is the site-wide procedure to be executed when an emergency that requires an evacuation occurs. This section provides general guidelines to be referenced when an evacuation is required. Read the entire page →
From page 328... ... 328 • General tips for lifting: – Check to see if mechanical aids such as hoists, lift trucks dollies, or wheelbarrows are available. – Be sure that the load is free to move. Read the entire page →
From page 329... ... 329 Raising Derrick (Mast) Read the entire page →
From page 330... ... 330 – Boat safety training and education may be obtained through a recognized outside source such as the United States Coast Guard Auxiliary. – Certified proof of course completion from one of these outside sources must be kept on record. Read the entire page →
From page 331... ... 331 • When a knife is not in use, the blade should be retracted and set off to the side. Be cautious of which side is the sharpened side. Read the entire page →
From page 332... ... 332 F.8.5 Communication The site supervisor should ensure that all field personnel have provided the proper contact information and that information is organized into a coherent list that contains field personnel name, cell phone number, emergency contact number, and information to emergency services such as fire, ambulance, and police. Routes and location information to the nearest hospital should be displayed on a map. Read the entire page →
From page 333... ... 333 F.8.6.3 Sanitation Work areas should be kept free of dirt and debris that may impact the safety of field personnel and visitors. All trash receptacles should be readily visible, accessible, and routinely emptied. Read the entire page →
From page 334... ... 334 G A P P E N D I X G Contracting Subsurface Investigations G.1 Introduction A recent trend is that transportation agencies, for a variety of reasons (e.g., reduction in in-house personnel, increased work load) , have increased their use of private engineering firms in conducting geotechnical investigations. Read the entire page →
From page 335... ... 335 • Requirements for licensing, professional registration, or certification • Permitted roles of subconsultants • Submittal requirements for the RFP or RFLOI • Selection process and selection criteria • Submission schedule and key dates G.2.1 Prequalification Prequalifying private engineering firms is one criteria agencies use to select firms that have the expertise, equipment, and experience to provide the geotechnical services that meet the agency's minimum acceptable quality. Prequalification requirements typically specify the following: • Qualification requirements for personnel performing geotechnical investigations, analysis, and reporting: This usually includes the minimum education and experience requirements as well as professional registrations and certifications. Read the entire page →
From page 336... ... 336 G.2.5 Submittal Requirements for RFP or RFLOI The submittal requirements for the RFP or RFLOI should, at a minimum, include the following: • The maximum page limitation for the RFP or RFLOI document • The breakdown of the services that will be provided by the prime firm and those that will be provided by the subconsultants • Method of submission of the document (i.e., electronic only, by mail only, or both) G.2.6 Selection Criteria and Selection Process The RFPs or RFLOIs should list the factors the agency will use to evaluate whether the firms that respond to the solicitation meet the minimum requirements listed in the solicitation. Read the entire page →
From page 337... ... 337 services the agency expects the firm to be able to perform in the areas of geotechnical investigations, laboratory testing, geotechnical design, performance monitoring, and performance testing. The general scope of work should also specify the terms and conditions governing the use of subconsultants, work standards that should be followed (e.g., agency's geotechnical manual, AASHTO, American Standard for Testing and Materials [ASTM] Read the entire page →
From page 338... ... 338 to the firm they have decided to assign the work to. The RFP usually requires the firm to develop a cost estimate for the anticipated work. Read the entire page →
From page 339... ... 339 needed to address the anticipated geotechnical issues and the design requirements as outlined in Chapter 3. The detailed scope of work should include the rationale used to make the following decisions: • Selection of the investigation equipment for the anticipated site conditions • Selection of the number of investigation locations • Selection of the depth of investigations at each investigation location • Selection of the required types of samples and the sampling frequency for each type of sample • Selection of the sampling equipment and borehole advancing methods • Selection of the in situ and laboratory testing program • Anticipated project schedule • Estimated cost for performing the investigation In summary, the deliverable for this phase of the work should include a detailed boring plan, sampling and testing program, anticipated project schedule, and estimated cost for performing the investigation. Read the entire page →
From page 340... ... 340 G.4.3 Quality Assurance/Quality Control Geotechnical data is used to make decisions that affect the performance of the transportation infrastructure for a very long period. Therefore, it is imperative for the firm to use sound QA/QC practices in executing geotechnical investigations for the transportation infrastructure as discussed in Appendix E Read the entire page →
From page 341... ... 341 G.4.4.2 Invoicing The agency should provide the firm with guidelines for preparing invoices to comply with the agency's policies and requirements. The guidelines should spell out the types of documentation (e.g., time sheets, receipts, subconsultant's invoices) Read the entire page →
From page 342... ... 342 References Commonwealth of Kentucky Transportation Cabinet. Read the entire page →
From page 343... ... 343 H A P P E N D I X H Technology Transfer Strategies H.1 Introduction In addition to the guidance provided in this manual, there are numerous resources available to assist geoprofessionals with planning and executing a sound geotechnical site investigation program; using the results to develop a ground model for planning, designing, constructing, and managing assets of a project; and reporting the results in a manner that facilitates peer review, communication with stakeholders, and potential future uses. This appendix provides a comprehensive, but not exhaustive, summary of these resources, including (i) Read the entire page →
From page 344... ... 344 • Geotechnical Engineering Circular No. 5 - Evaluation of Soil and Rock Properties. Read the entire page →
From page 345... ... 345 Arizona: https://www.azdot.gov/business/standards-and-guidelines • Guidelines for Geotechnical Investigation and Geotechnical Report Presentation. Arizona Department of Transportation. Read the entire page →
From page 346... ... 346 Idaho: http://apps.itd.idaho.gov/apps/manuals/manualsonline.html • Materials Manual. Idaho Transportation Department. Read the entire page →
From page 347... ... 347 • Geotechnical Policies and Procedures Manual. Nebraska Department of Roads. Read the entire page →
From page 348... ... 348 • Design Manual – Chapter VII – Geotechnical Studies and Design. North Dakota Department of Transportation. Read the entire page →
From page 349... ... 349 Vermont: http://vtrans.vermont.gov/highway/construct-material/geotech/engineering • Geotechnical Guidelines for the Subsurface Investigation Process. Vermont Agency of Transportation. Read the entire page →
From page 350... ... 350 H.4 Geotechnical Websites Websites maintained by federal agencies and organizations, and State DOTs also contain valuable information to assist geoprofessionals plan and conduct geotechnical site investigations. H.4.1 Federal Agencies and Organizations • Federal Highway Administration – Geotechnical Engineering https://www.fhwa.dot.gov/engineering/geotech/ • Transportation Research Board (TRB) Read the entire page →
From page 351... ... 351 • North Carolina Department of Transportation – Geotechnical Engineering https://connect.ncdot.gov/resources/Geological/Pages/default.aspx • Ohio Department of Transportation – Office of Geotechnical Engineering https://www.dot.state.oh.us/Divisions/Engineering/Geotechnical/Pages/default.aspx • Oklahoma Department of Transportation – Bridge Division Geotechnical Branch https://www.ok.gov/odot/Doing_Business/PreConstruction_Design/Bridge_Design/GeoTech_Services/ • Pennsylvania Department of Transportation. GINT Library and Data template (software to manage report, and database geotechnical information) Read the entire page →
From page 352... ... 352 H.5.1 Classroom and Web-based Training • National Highway Institute (NHI) : Web-based and instructor-led training: https://www.nhi.fhwa.dot.gov/course-search • American Society of Civil Engineering (ASCE) Read the entire page →

From page 251...

... 251 A A P P E N D I X A Geotechnical Instrumentation A.1 Purpose of Geotechnical Instrumentation Geotechnical instruments can be used in transportation projects before, during, and after construction and can play an important role in providing real-time or near real-time information on the health and serviceability of transportation infrastructure. Such information can be used to monitor the behavior or performance of structures and can be incorporated into an early warning system.