Section 2: Chapter Descriptions
Anchor: #i1000374About this Section
The following subsections describe the contents of Chapters 2-8 of the GPS User’s Manual. The hyperlinks found in this section will lead the reader to the “Overview” section of a chapter.
Anchor: #i1000387Chapter 2, Background
Chapter 2 provides background on surveying with GPS, including accuracy, error sources, and the process for handling errors. It presents information on surveying vertical networks with GPS and the basic differences of conventional and GPS methods.
Anchor: #i1000397Chapter 3, Accuracy Standards
Chapter 3 discusses local and network accuracy and provides information on the concepts, guidelines, standards and specifications, as well as methodologies associated with GPS survey accuracy standards. Additionally, it provides tables to illustrate coordinate tolerances and historical accuracy.
Anchor: #i1000407Chapter 4, Equipment and Resources
Chapter 4 presents information regarding the use of GPS instruments and equipment. It includes discussions on the requirements for accurate and consistent data collection for a variety of instruments and equipment. This chapter also provides information on Internet resources.
Anchor: #i1000417Chapter 5, Network Design
Chapter 5 discusses network design and includes the determination of the number and location of existing control stations for network constraints, as well as selection of new project control stations, and relative dispersion of network observations.
Anchor: #i1000427Chapter 6, GPS Survey Specifications
Chapter 6 covers specifications involved in the planning of a project, field data acquisition methods, field survey operations and procedures, data processing, analysis of the data, and documentation. This chapter also provides information on monumentation, survey methods, field survey operations and procedures, and data processing.
Anchor: #i1000437Chapter 7, Units, Data, and Metadata
Chapter 7 provides information regarding the units used in TxDOT work, horizontal and vertical datum, adjustment factors, requirements for delivering metadata lists and files, and provisions for conversions and transformations.
Anchor: #i1000447Chapter 8, Project Documentation and Deliverables to TxDOT
Chapter 8 TxDOT requirements for project documentation and deliverables are outlined in this chapter. Specifications on technical reports, digital data; control point data sheets and validation surveys are presented.
Anchor: #i1000457Appendix A, References
Appendix A contains a comprehensive list of references used in the preparation of this manual.
Anchor: #i1000467Appendix B, Glossary
Appendix B contains extensive GPS survey related terms and definitions.
Anchor: #i1000477Hyperlinks
Hyperlinks in this manual may appear as red, underlined text or as Web addresses. These hyperlinks take the reader to related information found within this manual, another manual, or outside the TxDOT Manual System.
Anchor: #i1000487How to Get Help
The district survey coordinators are available to answer questions and discuss procedures and specifications outlined in this manual. Additionally, the Information Systems Division provides a helpdesk number, which offers survey help from the Automated Survey Support Unit. Users may access the helpdesk by calling (512) 302-2350, press 3 for engineering support, and then 4 for surveying support.
As GPS technology advances, changes in the manual will be necessary. If there is a need for updates or corrections, please notify the district survey coordinator. TxDOT employees will also be able to find contact information for an area SCOS representative on the intranet Web site (crossroads) under the miscellaneous link, “TxDOT Surveying and Mapping.”
Anchor: #i1000504Printing
Please print double-sided.
CAUTION: Readers who rely on any printed portions of the manual should check the online manual regularly for revisions.