Glossary

This section explains some of the terms used in this manual.

Activity - When a layer is active its contents can influence any optimization or alignment modeling and costing. If a layer is inactive its contents have no impact on calculations. Active layers can contain inactive objects; for an object to influence calculations, both the object and the layer containing it must be active.

Alignment - An alignment is the product of an optimization. Each alignment generated by a Quantm optimization consists of an xyz spline of the route, plus descriptions of any earthworks, structures, etc., required for its construction.

Alignment file - An alignment file (extension.qab) is a data file that contains the complete descriptions of the alignments generated by a scenario.

Alignment Summary window - This floating popup window appears in optimization mode or review mode. It provides information about the alignment being viewed.

Area costs - Area costs reflect the cost of acquiring or clearing particular classes of land. To see the breakdown of these costs, view the Footprint Area Report. This is accessed through the Alignment Summary.

Bearing - A direction in the horizontal plane, measured in degrees clockwise from true north.

Bench - A flat area between slopes; often installed to assist drainage or stability.

Bridge - The Quantm system allows you to use several bridge types in a scenario with a differing cost per height of the structure. One bridge type is named as a default, and is used when a bridge is required but no type is specified.

Clearances (Vertical) - Vertical crossing clearances control the height at which alignments will cross features and zones. Clearances are specified relative to the natural surface, mean sea level or the local low point for zones; or relative to the natural surface, mean sea level or the centerline for linear features. The constraints can be: >a (greater than the reference altitude plus a meters), and/or <b (less than the reference altitude plus b meters).

Compaction factor - This factor indicates the volume of a geological material when compacted for fill relative to its volume before excavation.

Costs (Bridge) - The costing of bridges assumes a fixed cost per unit area of deck depending on its’ height. The area of deck spans between both abutment limits and therefore is affected by the abutment slope.

Costs (Culvert) - The cost of a crossing requiring a culvert will depend on the type and length of channel required, the cost of fill material as cover, and the cost of the portals where each channel enters and exits the earthworks.

Costs (Global) - Global costs apply to the entire study area and include placement of fill, dump, borrow, mass haul, and pavement.

Costs (Tunnel) - The costing of tunnels assumes a varying cost per unit distance of tunnel length plus a cost for each portal. The material excavated from the tunnel must be used as fill or else dumped.

Crossing - A crossing defines clearances and types of construction to be used when crossing a feature such as a road, river, railway or pipeline, or a zone such as a flood plain.

Culvert - A culvert consists of one or more channels (or cells) that allow waterways or other features to pass under a route. The volume of the channels reduces the quantity of fill, and the need to spread any loads requires a minimum covering of earth on top. In the Quantm system, a scenario can use several channel types.

Curve compensation - Curve compensation adjusts the limiting grades for sections of a railway during horizontal curves. The tighter the curve, the more limiting the grades.

Curve coordination - Coordination of horizontal and vertical curves on roads ensures that drivers can see approaching curves in time to take appropriate action. Coordination ensures that horizontal curves do not start at or beyond crests. The Pathfinder software uses driver’s eye height, sight distance, and object height to coordinate horizontal and vertical curves.

Customizable Structures - An alignment converted from a Quantm spline alignment in which it is possible to alter the length, type and locations of structures such as bridges, tunnels and retaining walls.

Design grades - Design grades define the limiting grades as observed from a vehicle travelling from the defined start to the defined finish. They permit the limiting grades to depend on the direction of travel, an important consideration when planning development roads and railways where loaded vehicles will normally travel in only one direction. The uphill design gradient is the steepest ascending grade that would be encountered by a vehicle traveling from Start to Finish. The downhill design gradient is the steepest descending grade that would be encountered traveling from Start to Finish, and is negative.

DTM - See Terrain model.

Earthwork limits - Earthwork limits control the maximum height of cut and fill an alignment generates. If the alignment goes beyond these limits, a structure such as a bridge or tunnel will be placed instead. Earthwork limits can be defined globally or by a zone.

Editable Alignment - An alignment converted from a Quantm spline alignment into a geometric alignment, comprising of curves and straights. Both the horizontal and vertical curves and straights can be edited using this geometric type.

Feature - A (linear) feature is a geographic object such as a road, river, or pipeline that may have to be crossed. The minimum description required includes the location of the feature, the nature of the crossing (for example, tunnel, bridge, culvert, or unspecified), and the vertical clearances.

Fixed costs - Fixed costs cannot affect the alignment but are included to ensure that the final cost estimates do not omit significant contributions.

Geological material - Geological materials are the building blocks of all earthwork calculations. Their definition includes quality, extraction cost, side slope, fraction usable, and compaction factor.

Geological type - A geological type describes how different geological materials are layered (type and thickness), and the vertical separation and width of benches in any cutting. Benches are stepped upwards from the road or rail alignment to the natural surface.

Geology - The area defined by the terrain is assumed to conform to the default geological type except where it is defined otherwise. Geological zones represent occurrences of geological types other than the default.

Geometry - See Regional geometry.

Geospatial imagery - The term geospatial imagery describes ortho-rectified and geocoded images produced from remote sensing satellite systems and aerial photography. It provides an extremely useful supplement to GIS databases as it shows what was on the ground when the image was taken. Imagery captured specifically for the project can be much more recent than data from other sources.

Group - Scenarios can be arranged in groups to provide structure to the project.

Intersection point - An alignment is defined by a sequence of straight lines that connect at intersection points. To meet necessary geometric standards, the actual road surface does not pass through the intersection points but passes to the side of them in flowing curves.

Job file - A job file (.opb) defines the optimization that is to be undertaken. It contains all data required for the optimization except the terrain model.

Label - All geographic objects possess a label to assist in identification. A label consists of a text string naming the object; hyperlinked icons below the text may link to supporting documents. Labels can be switched off by layer if the information they contain complicates the display without making a significant contribution to the aspect being studied. The labels for waystations, features, and zones can be moved independently of the object.

Layer - All spatially referenced data is arranged in layers for ease of manipulation. The term originated from sheets of transparent material bearing lines and zones that could be layered on maps to allow selected information to be viewed.

Layer view - The layer view of a scenario displays the various layers, initially in the order in which they were drawn. The terrain model is always drawn first, but you can change the order of the other layers by simple drag‑and‑drop operations. Layers can be opened to display their contents.

Legend window - The legend window is a floating popup window that provides information about the area being viewed. The legend window displays the color scheme for the terrain of the study area. In Review mode, the legend window also displays linear features within the study area, special and avoidance zones, earthworks, and the radius of the curvature or gradient (depending on which feature you are is viewing).

Material - See Geological material.

Mean natural surface - The mean natural surface refers to the mean altitude of natural surface 50 to 100 meters on either side of an alignment. As an alternative reference altitude to mean sea level, mean natural surface can be used to encourage alignments to follow low ridges across flood prone areas.

Mesh - On a plan view of the study area, the mesh is a square map grid showing distances in meters or feet. On a profile view of a route, the mesh shows the distance in meters or feet from the start of the route along the horizontal axis, against the elevation along the vertical axis.

Palette - The palette is a color scheme used by the Quantm system.

Plan view - A chart showing a plan view displays an overhead topographical representation of all or part of the study area. North is to the top of the screen. The plan is color-coded according to altitude unless it has a satellite image or aerial photograph as its background.

Preferences (Alignment) - These settings control the visual display of alignments in review mode, including the reporting of warnings and cost information.

Preferences (Feature) - These settings enable you to select the default feature color and line type.

Preferences (General) - These are general settings that relate to a variety of functions within the Integrator software. Settings include the option for Imperial or Metric units.

Preferences (Submission) - These settings control how job files are submitted.

Preferences (Zone) - These settings enable you to select default zone color and hatching.

Profile view - A chart showing a profile view of an alignment displays a representation of the terrain from along the length of the alignment(s), with the altitude of the land mapped against the distance along the alignment.

Project - Quantm projects are defined by data. The basis of a project is the terrain model (DTM), to which datasets, such as objects, costs, and geometry, are added to create different scenarios.

Quick object creation - If you are an advanced user, you can use Quick object creation to enter new objects, skipping the data entry dialog for the object type and using the previous object as a template. You must make the necessary changes in the Feature Properties box without prompting.

Regional geometry - Regional geometry defines which geometric standards the alignment has to conform to in the study area as a whole (the default geometry) or in specific zones.

Review mode - Whenthe system is in review mode, previously generated routes are displayed for examination.

Scenario - A Quantm scenario specifies a particular set of data to be investigated. The data includes the terrain model, the geometric standards to be applied to the alignments, how costs are generated, and the constraints that are imposed by geographic objects within the study area. Once a scenario has been used to run a job, it is locked so that it cannot be altered. This ensures that you can always view alignments under the conditions that were used to generate them.

Scenario log - The scenario log records the names of all data files that were used to create an individual scenario. It can also be used to aggregate the scenario notes and create a notes history file of previous scenarios. The log also indicates whether a particular scenario was used to create a corresponding operation file.

Scenario notes - The lower section of the Scenario Notes pane contains notes about the scenario, such as why it was created, the significance of changes from the parent scenario, and what it is seeking to investigate. The notes are automatically recorded in the database and, when the time comes to write up the project report, provide a useful record of how particular decisions were reached.

Scenario Explorer - Shows scenarios arranged in groups on the basis of meaningful criteria. Scenarios that can be edited are shown as a yellow folder, and those that are locked (not able to be edited) are shown as a gray folder with new results or scenarios with new results shown in bold. The view allows scenarios to be reordered within a group or moved from one group to another by dragging and dropping.

Slide slope - The (V:H) slope of the sides of fills, cuts, and retaining wall, defined as a percentage.

Status bar - The Quantm status bar is the row of text at the bottom of the workspace, which usually contains the x,y,z location of the cursor in plan or the chainage and earthworks information in profile. In addition, it also give the folder location of the data set, the number of currently selected features, any data warnings within the currently loaded scenario and also an icon for the type of alignment currently loaded.

Stiffness - Stiffness is a proxy for rate of change of curvature. The Quantm system contains two indices which integrate measures of local changes in horizontal and vertical curvature over the whole route. When the stiffness parameters are close to 0, the alignments follow the natural surface as closely as the geometric standards permit; when the stiffness parameters are close to 1, the alignments minimize changes in curvature as much as possible at the expense of higher construction costs. A resource railway should be stiffer than a minor local road. However, the appropriate stiffness may vary between projects and must be selected empirically.

Study area - The study area is the geographical region defined by the limits of the digital terrain model.

Superelevation - Superelevation is a cant applied to the road surface to increase traveller comfort and to reduce the tendency of a vehicle to fly off curves.

Sustained grade limits - Sustained grade limits constrain the average grade over a nominated distance to fall within a smaller range than the design grade limits. Use these limits to avoid long climbs or descents at the limiting design grades. The uphill sustained gradient is the steepest ascending grade that would be encountered by a vehicle traveling from Start to Finish. The downhill sustained gradient is the steepest descending grade that would be encountered travelling from Start to Finish, and is negative

Symbol - A symbol is a single character of any size in any True type font used to identify features on the display. Individual instances of a symbol can also have a unique name to supply further information. For example, H might be used to denote a hospital, with a label to supply the full name and hyperlinked documents to provide supporting information.

System units - Allows the project to be set in either metric units (meters) or imperial units (feet). The coordinate display, units, and distances will be in the selected units, as will any outputs to x,y,z files.

Terrain model - The form of terrain model employed by the Quantm system is based on a square mesh, where the easting of a point directly gives its row and the easting gives its column in the array. The terrain model is presented as an image that is color‑coded with respect to altitude, and shaded to provide increased detail on local variations. A terrain model is also called a digital terrain model or DTM

Transparency - Layers containing geospatial imagery can be rendered partially transparent. Rendering a layer transparent in this way allows layers that were drawn earlier to be partially visible. This is useful for matching terrain with aerial photography. See also Geospatial imagery. Transparency is controlled by a slider in the Layer View.

Tunnel - The Quantm system allows a scenario to use several tunnel types. One of these is named as the default, and is used when a tunnel is required but no type is specified.

V:H ratio - The V:H ratio is the ratio of the vertical scale to the horizontal scale used by the Quantm system when drawing a profile view of a route. The default ratio is 10:1.

Vertical Editable Alignment - An alignment converted from a Quantm spline alignment into a geometric alignment, comprising of curves and straights. Only the vertical curves and straights can be edited using this geometric type.

Visibility - You can make a layer invisible if the information it contains complicates the display without making a significant contribution to the aspect currently being studied.

Wall - A retaining wall is introduced to reduce the magnitude of cut or fill when the slope of the natural surface and the slope of the earthworks are nearly parallel. Quantm allows a scenario to use several types of retaining wall. One of the wall types is named as a default to be used when a wall is required but no type is specified.

Warning - A warning occurs when an alignment approaches the limits of any constraint. Warnings can be: vertical clearance, design grade, sustained grade, horizontal and vertical radii, and potential drainage problems. The sections of the route where violations occur are highlighted in light red.

Waystation - An waystation is a location the alignment must visit. A 2D waystation requires an alignment to pass within a fixed horizontal distance of a set of x,y coordinates.

Zone - A zone is a region within the study area that requires special treatment for social, environmental or engineering reasons. Some zones should be avoided, and others can be crossed subject to particular conditions. Zones can also be used to specify changes in geology or geometric standards.

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