==>>CLASSIFICATION OF SOILS FOR HIGHWAY USE<<==

                    ==>>CLASSIFICATION OF SOILS FOR HIGHWAY USE<<==

==>>

Soil classification is a method by which soils are systematically categorized according to their probable engineering characteristics. It therefore serves as a means of identifying suitable subbase materials and predicting the probable behavior of a soil when used as subgrade material.

The classification of a given soil is determined by conducting relatively simple tests on disturbed samples of the soil; the results are then correlated with field experience. Note, however, that although the engineering properties of a given soil to be used in highway construction can be predicted reliably from its classification, this should not be regarded as a substitute for the detailed investigation of the soil properties.

Classifying the soil should be considered as a means of obtaining a general idea of how the soil will behave if used as a subgrade or subbase material.

The most commonly used classification system for highway purposes is the American Association of State Highway and Transportation Officials (AASHTO) Classification System. The Unified Soil Classification System (USCS) also is used to a lesser extent. A slightly modified version of the USCS is used fairly extensively in the United Kingdom.

==>>AASHTO Soil Classification System==>>


The AASHTO Classification System is based on the Public Roads Classification System that was developed from the results of extensive research conducted by theBureau of Public Roads, now known as the Federal Highway Administration. Several revisions have been made to the system since it was first published. The system has been described by AASHTO as a means for determining the relative quality of soils for use in embankments, subgrades, subbases, and bases.

==>>Unified Soil Classification System (USCS)==>>


The original USCS system was developed during World War II for use in airfield construction. That system has been modified several times to obtain the current version which also can be applied to other types of construction such as dams and foundations. The fundamental premise used in the USCS system is that the engineering properties of any coarse-grained soil depend on its particle size distribution,whereas those for a fine-grained soil depend on its plasticity. Thus, the systemclassifies coarse-grained soils on the basis of grain size characteristics and fine-grained soils according to plasticity characteristics.


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==>>STEPS IN FUNCTIONALLY CLASSIFYING RURAL, URBAN AND URBANIZED AREA ROADWAYS<<==

==>>STEPS IN FUNCTIONALLY CLASSIFYING RURAL, URBAN AND
URBANIZED AREA ROADWAYS<<==

The Functional Classification flowchart,in whichfunctional classification development is recommended. This flow of activities logically takes you through the coordination process and the order of events required to obtain FHWA functional classification approval.

Using the new approved urban area boundary map:
1. Prepare a map showing the road network and the existing federal functional
classification superimposed over the new approved boundary map

2. Add land service characteristics, such as major traffic generators and land use
patterns. Current DOQQs are a good resource if available for your area.

3. Reclassify the functional classification for highway and streets where land service
characteristics have changed. NOTE* The revised functional classification will be
coded, as proposed. This will be a new characteristic.
DO NOT change the existing functional classification characteristic.

When reclassifying roads, remember to include logical system continuity
considerations. Select principal arterial systems first, followed by minor arterials,
then collectors and locals.

• Perform a preliminary classification of the total arterial system considering the list below Evaluate service to urban activity centers Consider system continuity .Determine land use considerations
Evaluate spacing between routes and the spatial distribution of activities to be served Average trip length
Traffic volumes (AADT) Access control Vehicle miles of travel and system mileage

• Classify the final arterial system breaking it into the principal and minor arterialstreet system By
service to urban activity centers
• Business districts
• Air, rail, bus, and truck freight terminals
• Regional retail shopping centers
• Large colleges, hospital complexes, military bases, and other
institutional facilities

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==>>Sub Surface Highway Drainage<<==

==>>Sub Surface Highway Drainage<<==

• Subgrade may be damaged by sub soil water.
• Sub soil water as free water, when water table is high or it may come up by capillary action to the subgrade when water table is low.
• Subgrade should be of self draining material so that it may pass off the percolation water that comes to it to remain dry and stable.
• But if subgrade is of soft and retentive soil, or there are underground dprings bringing free water to the subgrade fro that reason subsurface drains should be constructed about 1 ½’ to 2’ below the formation level to carry away water from the subgrade and thus keep it dry. ( in easily drainable soil water can be lowered by deep or open side drains, it also takes rain water.
• Cross-drains may be in the form of trapezoidal trenches filled with selected rubble called rubbled drains or trench drains.
• Depth is not much and the discharge is small.
• The pipes are surrounded by filler material and the remaining of the cross trench is filled with graded rubble,  the bigger size rubble being nearer to the pipe. Water of wet subgrade passes through the open joint of pipes and enter the lateral drain which discharge into the longitudinal drain pipe in the two longitudinal side trenches.
• Longitudinal drain carry water to the nearby stream.
• Cross-drains, staggered in herring bone fashion.
• Spacing of lateral drains is less in impermeable soil and more in permeable soil.

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==>>Costs of Highways==>>

                            

                                                   ==>>Determining Relevant Costs:              

           ==>>

            The total cost for improvements to a highway system or segment includes engineering and design, expenditures for planning, the outlay for acquiring rights of way, and the costs of constructing roadway, structures, and pavements. Selection of the cost items to be included in and excluded from specific economy studies requires straight and careful thinking. A detailed discussion is beyond the scope of this book. However, four of the most important considerations are as follows:

1.      In general, allocated costs, used for accounting purposes, should be omitted from economy studies. To illustrate, a given percentage may be added to estimated project costs for administration, planning, and engineering overhead. These costs probably will be incurred whether or not a specific project is undertaken; if so, they are not relevant in comparisons between possible courses of action. Stated differently, only the added or incremental costs are relevant.

2.      Expenditures made before the time of the economy study should not be considered. These are called sunk costs, in that they cannot be recovered by any present or future action. For example: the roadway and pavement of an existing road may be in good condition and have a substantial “book value” in the records of the highway agency. Nevertheless, if one alternatives in the economy study. Again, it would be improper to include costs incurred earlier for preliminary planning and design.

3.      All relevant costs must be included and all irrelevant charges excluded. In this regard, as mentioned earlier, transferred costs may be particularly trouble some. Assume, for example, that one of several plans for a proposed highway improvement requires a private utility company to move its facilities at its own expense. From a budgetary standpoint this cost is not chargeable against the project from a public works economy-study standpoint; however it is a proper charge. Economic resources are consumed. Even though paid from private rather than public funds.

4.      In certain types of economy studies. It is proper to make an allowance for the salvage value of a machine or structure at the end of its estimated useful life. As a general rule, salvage value should be neglected in economic studies for highways. It is conjectural at best to assume that an investment in a highway will have great worth 20, 30, or 40 yr in the future. One exception might be to assign salvage value to the land occupied by the road. Even in this situation only the raw value of the land in its predicted future use, after deducting the cost of converting it to that use, would be included. Other costs associated with acquiring the land in the first place, such as legal expenses and the cost of cleaning it of buildings cannot be recovered and would not be a part of the salvage value.

Proposed highway improvements often will bring changes in annual maintenance and operating costs. For present conditions, data for these should available from the cost records of the highway agency. Estimates of these costs for the proposed improvements must be projected. Here again, only the relevant costs are to be sure that only true cost differences are reflected.

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==>>BASIC INSTRUMENTS USED IN SURVEYING==>>

=> Chain or tape
=> Arrows
=> Ranging rods
=> Cross staff
=> Offset rods
=> Pegs
=> Plumb bob

 Chain:==>>

The chain is composed of 100 or 150 pieces of galvanized mild steel wire, 4mm in diameter called links .The ends of each link are bent into a loop and connected together by means of three oval rings. The ends of the chain are provided with handles for dragging the chain on the ground, each wire with a swivel joint so that the chain can be turned without twisting. The length of the chain is measured from the outside of one handle to the outside of another handle.

Following are the various types of chain in common use:
1) Metric chains
2) Gunter` s chain or surveyors chain
3) Engineers chain
4) Revenue chain
5) Steel band or Band chain


 Tapes==>>
The following are the various types of tapes
=> Cloth tape
=> Metallic tape
=> Steel tape
=> Invar tape
Among the above, metallic tapes are widely used in surveying. A metallic tape is made of varnished strip of waterproof line interwoven with small brass, copper or bronze wires. These are light in weight and flexible and are made 2m, 5m 10m, 20m, 30m, and 50m.


Arrows=>
Arrows are made of good quality hardened steel wire of 4 mm diameter. The arrows are made 400 mm in length, are pointed at one and the other end is bent into a loop or circle

Ranging rods==>>
Ranging rods are used to range some intermediate points in the survey line The length of the ranging rod is either 2m or 3m. They are shod at bottom with a heavy iron point. Ranging rods are divided into equal parts 0.2m long and they are painted alternately black and white or red and white or red, white and black. When they are at considerable distance, red and white or white and yellow flags about 25 cm square should be fastened at the top.


Cross staff==>>
The simplest instrument used for setting out a right angle. The common forms of cross staff are: Open cross staff, French cross staff,Adjustable cross staff

OFFSET ROD==>>
The offset rod is used for measuring the off set of short lengths. It is similar to a ranging rod and is usually of 3m lengths.

PEGS==>>
These are rods made from hard timber and tapered at one end, generally 25mm or 30mm square and 150mm long wooden pegs are used to mark the position of the station on.

PLUMB BOB==>>
While chaining along sloping ground, a plumb bob is required to transfer the points to the ground.

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===>> PRINCIPLE OF BRIDGE LOCATION<<===

===>> PRINCIPLE OF BRIDGE LOCATION<<===

==>>>

The basic principle for locating highway bridges is that the highway location should determine the bridge location, not the reverse. When the bridge is located first, in most cases the resulting highway alignment is not the best. The general procedure for most highways, therefore, is to first determine the best highway location and then determine the bridge site. In some cases, this will result in skewed bridges, which are more expensive to construct, or in locations where foundation problems exist. When serious problems of this nature occur, all factors such as highway alignments, construction costs of the bridge deck and its foundation, and construction costs of bridge approaches should be considered in order to determine a compromise route alignment that will give a suitable bridge site. This will include completing the transportation
planning process and the economic evaluation of the benefits and costs..

A detailed report should be prepared for the bridge site selected to determine whether there are any factors that make the site unacceptable. This report should include accurate data on soil stratification, the engineering properties of each soil stratum at the location, the crushing strength of bedrock, and water levels in the
channel or waterway.

 When the waterway to be crossed requires a major bridge structure, however, it is
necessary to first identify a narrow section of the waterway with suitable foundation conditions for the location of the bridge and then determine acceptable highway alignments that cross the waterway at that section. This will significantly reduce the cost of bridge construction in many situations.

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==>>LIME ==>>

PURE LIMESTONE=>
Is called calcite and that containing magnesite is called dolomitic limestone.
The mineral containing calcium carbonate and magnesium carbonate in equimolecular quantities
is called dolomite.

STONE LIMESTONE=>
Is almost pure lime obtained by calcination of limestone and is used for making
lime-sand mortar for superstructures; lime-surkhi mortar for substructures and: lime terracing
and flooring. Stone lime has hydraulic properties.

KANKAR LIMESTONE=>
Is an impure lime obtained by calcination of kankars dug out from underground
sources. These occur in the form of nodules and compact blocks. It is suitable for making limesand
mortars for substructures. It is commonly used for making hydraulic lime.

SHELL LIMESTONE=>
Is very pure lime obtained by calcination of shells of sea animals and corals. It is used for lime punning,
white wash and colour wash, soil stabilization and glass production.

MAGNESIAN LIME=>
Is manufactured from dolomite and contain magnesia more than 5 per cent. It
is used for making mortar and plaster.


PURE LIME=> [Cao]
Pure lime, generally called quick lime, is a white oxide of calcium. Much of
commercial quick lime, however, contains more or less magnesium oxide, which gives the
product a brownish or grayish tinge. Quick lime is the lime obtained after the calcination of
limestone. It is also called caustic lime. It is capable of slaking with water and has no affinity for
carbonic acid. The specific gravity of pure lime is about 3.40.

FAT LIME=>
Fat lime has high calcium oxide component and, sets and hardens by the absorption of CO2
from atmosphere. These are manufactured by burning marble, white chalk, calcareous tufa,
pure lime stone, sea shell and coral.

HYDRAULIC LIME=>
Contains small quantities of silica, alumina, iron oxide in chemical combination
with calcium oxide component. These are produced from carboniferous limestones and
magnesian limestone. It has the property to set and harden under water.

HYDRATE LIME=>
When quick lime is finely crushed, slaked with a minimum amount of water,
and screened or ground to form a fine homogeneous powder the product is called hydrated
lime.

LUMP LIME=>
Lume lime is the quick-lime coming out of the kilns.

MILK LIME=>
Milk lime is a thin pourable solution of slaked lime in water.

CHARACTERSTICS OF LIME==>>

1. Lime possesses good plasticity and is easy to work with.
2. It stiffens easily and is resistant to moisture.
3. The excellent cementitious properties make it most suitable for masonry work.
4. The shrinkage on drying is small because of its high water retentivity.

USES OF LIME==>>
In construction slaked lime is mainly used to make mortar for laying masonry and plastering. When so used quick lime should be completely hydrated by slaking from 3 to 14 days, depending upon the kind of lime, temperature, and slaking conditions. Hydrated lime, although immediately usable, is usually improved by soaking overnight or longer. Hydrated lime is often added to Portland cement mortar in proportions varying from 5 to 85 per cent of the weight of the cement to increase plasticity and workability. Most of the historical buildings had been plastered in lime. Lime punning—about 3 mm thick shell lime layer to improve the plastered surfaces and to give a shining appearance—is used very commonly now a days in the new structures. Some of the other uses of lime are manufacture of lime bricks, artificial stones, paints, glass; as stabilizer for soils and as a flux in metallurgical processes.

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==>>Indian Academy of Highway Engineers ==>> ( IAHE )

==>>Indian Academy of Highway Engineers ==>> ( IAHE )

==>>

Is the apex training institute set up to address the training needs of Highway and Bridge Engineers in the country. It was set up as an Institute in the year 1983 with the primary objective to fulfill the need for training of highway engineers at the entry level and during the service.

IAHE conducts regular training programmes for the Engineers & highway sector professionals of Central Govenment organizations, State Government organizations, Public sector units, private sector, stake holders of multi-lateral agencies like World Bank, Asian Development Bank, etc.

On specific demand, customized training programmes for Engineers & highway sector professionals or Indian organizations as well as Foreign organizations are also conducted.

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==>> What are the advantages of using rockfill over earthfill to build road embankment? <<==

==>> What are the advantages of using rockfill over earthfill to build road embankment? <<==

==>>
With the use of rockfill to build embankment, it is not a concern regarding the build-up of pore water pressure during construction so that the embankment can be filled at the faster rate. Moreover, the use of rockfill
allows a steeper angle in forming road embankment when compared with earthfill so that it results in a small amount of fill. As such, it helps save the cost of construction.

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==>>3D TOOLS USED IN AUTO CAD==>>

==>>3D TOOLS USED IN AUTO CAD==>>

FOR 2D TOOLS CLICK ON THIS LINK==>>

2D TOOLS USED IN CIVIL ENGINEERING

3darray – Creates an array of 3D models in 3D space
3dface (3f) – Creates a 3- or 4-sided 3D mesh behind which other features
can be hidden
3dmesh – Creates a 3D mesh in 3D space
3dcorbit – Allows methods of manipulating 3D models on screen
3ddistance – Allows the controlling of the distance of 3D models from the operator
3dfl y – Allows walkthroughs in any 3D plane
3dforbit – Controls the viewing of 3D models without constraint
3dmove – Shows a 3D move gizmo. Moves 3D objects
3dorbit (3do) – Allows a continuous movement and other methods of
manipulation of 3D models on screen
3dorbitctr – Allows further and a variety of other methods of
manipulation of 3D models on screen

3dpan – Allows the panning of 3D models vertically and horizontally on screen
3drotate – Displays a 3D rotate gizmo. Rotates 3D objects
3dscale – Shows a 3D scale gizmo. Scales 3D objects
3dsin – Brings the 3D Studio File Import dialog on screen
3dsout – Brings the 3D Studio Output File dialog on screen
3ddwf – Brings up the Export 3D DWF dialog on screen
3dwalk – Starts walk mode in 3D
anipath – Opens the Motion Path Animation dialog
Align – Allows selected entities to be aligned to selected points in 3D space
Ameconvert – Converts AME solid models (from Release 12) into
AutoCAD 2000 solid models
Box – Creates a 3D solid box

Cone – Creates a 3D model of a cone
convertoldlights – Converts lighting from previous releases to AutoCAD
2010 lighting
convertoldmaterials – Converts materials from previous releases to
AutoCAD 2010 materials
convtosolid – Converts plines and circles with thickness to 3D solids
convtosurface – Converts objects to surfaces
Cylinder – Creates a 3D cylinder
Dducs (uc) – Brings the UCS dialog on screen
Edgesurf – Creates a 3D mesh surface from four adjoining edges
Extrude (ext) – Extrudes a closed polyline
Flatshot – Brings the Flatshot dialog to screen
Freepoint – Point light created without settings
Freespot – Spot light created without settings
Helix – Constructs a helix
Interfere – Creates an interference solid from a selection of several solids
Intersect (in) – Creates an intersection solid from a group of solids
Light – Enables different forms of lighting to be placed in a scene
Lightlist – Opens the Lights in Model palette
Loft – Activates the Loft command

Materials – Opens the Materials palette
Matlib – Outdated instruction
Mesh – Can be used to set tessellations for a 3D primitive
Meshrefi ne – Refi nes the meshing of a 3D object
Meshsmooth – Increases the smoothness of 3D objects
Meshsmooth – Smoothes outlines of 3D objects
Mirror3d – Mirrors 3D models in 3D space in selected directions
Mview (mv) – When in PSpace brings in MSpace objects
Pface – Allows the construction of a 3D mesh through a number of
selected vertices
Plan – Allows a drawing in 3D space to be seen in plan (UCS World)
Planesurf – Creates a planar surface
Pointlight – Allows a point light to be created

Pspace (ps) – Changes MSpace to PSpace
Pyramid – Creates a pyramid
-render – Can be used to make rendering settings from the command line.
Note the hyphen ( - ) must precede render
Renderpresets – Opens the Render Presets Manager dialog
Renderwin – Opens the Render window
Revolve (rev) – Forms a solid of revolution from outlines
Revsurf – Creates a solid of revolution from a pline
Rmat – Brings the Materials palette on screen
Rpref (rpr) – Opens the Advanced Render Settings palette

Section (sec) – Creates a section plane in a 3D model
Shade (sha) – Shades a selected 3D model
Slice (sl) – Allows a 3D model to be cut into several parts
Solprof – Creates a profi le from a 3D solid model drawing
Sphere – Creates a 3D solid model sphere
Spotlight – Creates a spotlight
Stlout – Saves a 3D model drawing in ASCII or binary format
Sunproperties – Opens the Sun Properties palette
Sweep – Creates a 3D model from a 2D outline along a path

Tabsurf – Creates a 3D solid from an outline and a direction vector
Torus (tor) – Allows a 3D torus to be created
Ucs – Allows settings of the UCS plane
Union (uni) – Unites 3D solids into a single solid
View – Creates view settings for 3D models
Visualstyles – Opens the Visual Styles Manager palette
Vpoint – Allows viewing positions to be set from x,y,z entries
Vports – Brings the Viewports dialog on screen
Wedge (we) – Creates a 3D solid in the shape of a wedge
Xedges – Creates a 3D wireframe for a 3D solid


INTERNAL TOOLS==>>

Etransmit – Brings the Create Transmittal
Publish – Brings the Publish dialog to screen

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==>> USE OF AUTO CAD IN CIVIL ENGINEERING==>>

AUTO CAD==>>  Automatic Computer Aided Design
It is useful for building construction to draw 3D view of buildings parts in computer...

AutoCAD 2010 allows the use of over 300 tools. Some operators prefer using the word “ commands ” , although command as an alternative to tool is not in common use today. The abbreviations for tools which can be abbreviated are included in brackets after the tool name. Tool names can be entered in upper or lower case.
2D and 3D both work can be done in AUTOCAD

2D TOOLS USED IN AUTO CAD==>>

FOR 3D TOOLS CLICK ON THIS LINK==>>

3D TOOLS USED IN AUTO CAD


About – Brings the About AutoCAD bitmap on screen
Appload – Brings the Load/Unload Applications dialog to screen
Adcenter (dc) – Brings the DesignCenter palette on screen
Align (al) – Aligns objects between chosen points
Arc (a) – Creates an arc
Area – States in square units the area selected from a number of points
Array (ar) – Creates Rectangular or Polar arrays in 2D
Ase – Brings the dbConnect Manager on screen
Attdef – Brings the Attribute Defi nition dialog on screen
Attedit – Allows editing of attributes from the Command line
Audit – Checks and fi xes any errors in a drawing
Autopublish – Creates a DWF fi le for the drawing on screen
Bhatch (h) – Brings the Boundary Hatch dialog on screen
Block – Brings the Block Defi nition dialog on screen
Bmake (b) – Brings the Block Defi nition dialog on screen
Bmpout – Brings the Create Raster File dialog on screen
Boundary (bo) – Brings the Boundary Creation dialog on screen
Break (br) – Breaks an object into parts
Cal – Calculates mathematical expressions
Chamfer (cha) – Creates a chamfer between two entities
Chprop (ch) – Brings the Properties window on screen
Circle (c) – Creates a circle
Copytolayer – Copies objects from one layer to another

Copy (co) – Creates a single or multiple copies of selected entities
Copyclip (Ctrl C) – Copies a drawing or part of a drawing for inserting
into a document from another application
Copylink – Forms a link between an AutoCAD drawing and its
appearance in another application such as a word-processing package
Customize – Brings the Customize dialog to screen, allowing the
customisation of toolbars, palettes etc.
Dashboard – Has the same action as Ribbon
Dashboardclose – Closes the Ribbon
Ddattdef (at) – Brings the Attribute Defi nition dialog to screen
Ddatte (ate) – Edits individual attribute values
Ddcolor (col) – Brings the Select Color dialog on screen
Ddedit (ed) – The Text Formatting dialog box appears on selecting text
Ddim (d) – Brings the Dimension Style Manager dialog box on screen
Ddinsert (i) – Brings the Insert dialog on screen
Ddmodify – Brings the Properties window on screen
Ddosnap (os) – Brings the Drafting Settings dialog on screen
Ddptype – Brings the Point Style dialog on screen
Ddrmodes (rm) – Brings the Drafting Settings dialog on screen
Ddunits (un) – Brings the Drawing Units dialog on screen
Ddview (v) – Brings the View Manager on screen
Del – Allows a fi le to be deleted
Dgnexport – Creates a MicroStation V8 dgn fi le from the drawing on
screen
Dgnimport – Allows a MicroStation V8 dgn fi le to be imported as an
AutoCAD dwg fi le

Dim – Starts a session of dimensioning
Dimension tools – The Dimension toolbar contains the following tools –
Linear , Aligned , Arc Length , Ordinate , Radius , Jogged , Diameter ,
Angular , Quick Dimension , Baseline , Continue , Quick Leader ,
Tolerance , Center Mark , Dimension Edit , Dimension Edit Text ,
Update and Dimension Style
Dim1 – Allows the addition of a single dimension to a drawing
Dist (di) – Measures the distance between two points in coordinate units
Distantlight – Creates a distant light
Divide (div) – Divides an entity into equal parts
Donut (do) – Creates a donut
Dsviewer – Brings the Aerial View window on screen
Dtext (dt) – Creates dynamic text. Text appears in drawing area as it is
entered
Dxbin – Brings the Select DXB File dialog on screen
Dxfi n – Brings the Select File dialog on screen
Dxfout – Brings the Save Drawing As dialog on screen

Ellipse (el) – Creates an ellipse
Erase (e) – Erases selected entities from a drawing
Exit – Ends a drawing session and closes AutoCAD 2010
Explode (x) – Explodes a block or group into its various entities
Explorer – Brings Windows Explorer on screen
Export (exp) – Brings the Export Data dialog on screen
Extend (ex) – To extend an entity to another
Fillet (f) – Creates a fi llet between two entities
Filter – Brings the Object Selection Filters dialog on screen
Gradient – Brings the Hatch and Gradient dialog on screen

Group (g) – Brings the Object Grouping dialog on screen
Hatch – Allows hatching by the entry responses to prompts
Hatchedit (he) – Allows editing of associative hatching
Help – Brings the AutoCAD 2010 Help: User Documentation dialog on
screen
Hide (hi) – Hides parts behind 3D meshes in 3D models
Id – Identifi es a point on screen in coordinate units
Imageadjust (iad) – Allows adjustment of images
Imageattach (iat) – Brings the Select Image File dialog on screen
Imageclip – Allows clipping of images
Import – Brings the Import File dialog on screen
Insert (i) – Brings the Insert dialog on screen
Insertobj – Brings the Insert Object dialog on screen
Isoplane (Ctrl E) – Sets the isoplane when constructing an isometric
drawing

Join (j) – Joins lines which are in line with each other or arcs which are
from the same centre point
Laycur – Changes layer of selected objects to current layer
Layer (la) – Brings the Layer Properties Manager dialog on screen
Layout – Allows editing of layouts
Lengthen (len) – Lengthens an entity on screen
Limits – Sets the drawing limits in coordinate units
Line (l) – Creates a line
Linetype (lt) – Brings the Linetype Manager dialog on screen
List (li) – Lists in a text window details of any entity or group of entities
selected

Load – Brings the Select Shape File dialog on screen
Ltscale (lts) – Allows the linetype scale to be adjusted
Measure (me) – Allows measured intervals to be placed along entities
Menu – Brings the Select Customization File dialog on screen
Menuload – Brings the Load/Unload Customizations dialog on screen
Mirror (mi) – Creates an identical mirror image of selected entities
Mledit – Brings the Multiline Edit Tools dialog on screen


Mline (ml) – Creates mlines
Mlstyle – Brings the Multiline Styles dialog on screen
Move (m) – Allows selected entities to be moved
Mslide – Brings the Create Slide File dialog on screen
Mspace (ms) – When in PSpace changes to MSpace
Mtext (mt or t) – Brings the Multiline Text Editor on screen
Mview (mv) – To make settings of viewports in Paper Space
Mvsetup – Allows drawing specifi cations to be set up
New (Ctrl N) – Brings the Select template dialog on screen
Notepad – For editing fi les from Windows Notepad
Offset (o) – Offsets selected entity by a stated distance
Oops – Cancels the effect of using Erase
Open – Brings the Select File dialog on screen
Options – Brings the Options dialog to screen

Ortho – Allows ortho to be set ON/OFF
Osnap (os) – Brings the Drafting Settings dialog to screen
Pagesetup – Brings either the Page Setup Manager on screen
Pan (p) – Drags a drawing in any direction
Pbrush – Brings Windows Paint on screen
Pedit (pe) – Allows editing of polylines. One of the options is Multiple ,
allowing continuous editing of polylines without closing the command
Pline (pl) – Creates a polyline
Plot (Ctrl P) – Brings the Plot dialog to screen
Point (po) – Allows a point to be placed on screen
Polygon (pol) – Creates a polygon
Polyline (pl) – Creates a polyline
Preferences (pr) – Brings the Options dialog on screen
Preview (pre) – Brings the print/plot preview box on screen
Properties – Brings the Properties palette on screen
Psfi ll – Allows polylines to be fi lled with patterns
Psout – Brings the Create Postscript File dialog on screen
Purge (pu) – Purges unwanted data from a drawing before saving to fi le
Qsave – Saves the drawing fi le to its current name in AutoCAD 2010
Quickcalc (qc) – Brings the QUICKCALC palette to screen
Quit – Ends a drawing session and closes down AutoCAD 2010
Ray – A construction line from a point
Recover – Brings the Select File dialog on screen to allow recovery of
selected drawings as necessary
Recoverall – Repairs damaged drawing
Rectang (rec) – Creates a pline rectangle
Redefi ne – If an AutoCAD command name has been turned off by
Undefi ne , Redefi ne turns the command name back on
Redo – Cancels the last Undo

edrawall (ra) – Redraws the whole of a drawing
Regen (re) – Regenerates the contents of the AutoCAD 2010 drawing area

Regenall (rea) – Regenerates the whole of a drawing
Region (reg) – Creates a region from an area within a boundary
Rename (ren) – Brings the Rename dialog on screen
Revcloud – Forms a cloud-like outline around objects in a drawing to
which attention needs to be drawn
Ribbon – Brings the ribbon on screen
Ribbonclose – Closes the ribbon
Save (Ctrl S) – Brings the Save Drawing As dialog box on screen
Saveas – Brings the Save Drawing As dialog box on screen
Saveimg – Brings the Render Output File dialog on screen
Scale (sc) – Allows selected entities to be scaled in size – smaller or larger
Script (scr) – Brings the Select Script File dialog on screen
Setvar (set) – Can be used to bring a list of the settings of set variables
into an AutoCAD Text window
Shape – Inserts an already loaded shape into a drawing
Shell – Allows MS-DOS commands to be entered
Sketch – Allows freehand sketching
Solid (so) – Creates a fi lled outline in triangular parts
Spell (sp) – Brings the Check Spelling dialog on screen
Spline (spl) – Creates a spline curve through selected points
Splinedit (spe) – Allows the editing of a spline curve
Status – Shows the status (particularly memory use) in a Text window
Stretch (s) – Allows selected entities to be stretched
Style (st) – Brings the Text Styles dialog on screen
Tablet (ta) – Allows a tablet to be used with a pointing device
Tbconfi g – Brings the Customize User Interface dialog on screen to
allow configuration of a toolbar
Text – Allows text from the Command line to be entered into a drawing
Thickness (th) – Sets the thickness for the Elevation command
Tilemode – Allows settings to enable Paper Space
Tolerance – Brings the Geometric Tolerance dialog on screen
Toolbar (to) – Brings the Customize User Interface dialog on screen
Trim (tr) – Allows entities to be trimmed up to other entities
Type – Types the contents of a named fi le to screen
UCS – Allows selection of UCS (User Coordinate System) facilities
Undefi ne – Suppresses an AutoCAD command name
Undo (u) (Ctrl Z) – Undoes the last action of a tool

View – Brings the View dialog on screen
Vplayer – Controls the visibility of layers in Paper Space
Vports – Brings the Viewports dialog on screen
Vslide – Brings the Select Slide File dialog on screen
Wblock (w) – Brings the Create Drawing File dialog on screen
Wmfi n – Brings the Import WMF dialog on screen
Wipeout – Forms a polygonal outline within which all crossed parts of
objects are erased
Wmfopts – Brings the WMF in Options dialog on screen
Wmfout – Brings the Create WMF File dialog on screen
Xattach (xa) – Brings the Select Reference File dialog on screen
Xline – Creates a construction line
Xref (xr) – Brings the Xref Manager dialog on screen
Zoom (z) – Brings the zoom tool into action

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==>>A Study of Axle Overloadings On A Rural Road In Nigeria <<==

==>>A Study of Axle Overloadings On A Rural Road In Nigeria <<==


This paper presents the outcome of the axle load survey on a section of a rural trunk road in Nigeria in order to ascertain the contribution of overloaded goods vehicles to pavement failure. Seven day classified traffic and axle load survey was conducted for the determination of ADT, percentage heavy vehicle and the imposed axle load at respective axle position for the traversing vehicles on the Old Jos –Kaduna road, Kaduna state Nigeria. The proportion of the vehicle laden weight carried by each axle and the corresponding standard axle load (sal) was computed with the index model of power 4. The percentage and magnitude of overloaded axles were respectively determined as an indicative measure of the extent of structural damage to the pavement. The studied pavement was overstressed up to five times beyond the Nigeria standard axle load of 80kN, which was too high and hence constituting the hindsight to frequent structural damage to road pavements in Nigeria. It was recommended that the axle load control with weigh-in-motion weighing bridges to assure protection of the road from failure be instituted that will impact less disturbance to normal traffic flow on the arterial.

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==>>QUESTION BASED ON SURVEYING<<==

1. Define Tacheometer.
It is an ordinary transit theodolite fitted with an extra lens called analytic
lens. The purpose of fitting the analytic lens is to reduce the additive constant to zero.


2. Define Substance bar:
A Substance bar is manufactured by Mr. Kern. The length of the substance bar is
2m (6ft) for measurement of comparatively short distance in a traverse. A Substance bar
may be used as a substance base. The length of the bar is made equal to the distance
between the two targets.


3. What do you mean by Fixed hair method:
In this method, the stadia wires are fixed (or) fitted at constant distance apart.


4. State Stadia intercept:
The difference of the distance between the top and bottom cross hairs is called as staff
intercept


5. What do you mean by tangential method:
In this method, the stadia hairs are not for taking readings. The readings being
taken against the horizontal cross hair.
.
6. The tangential method:
In this method, the stadia hairs are not for taking readings. The readings being
taken against the horizontal cross hair.


7. What is the principle of stadia method?
The method is based on the principle that the ratio of the perpendicular to the base
is constant to similar isosceles triangle.


8. What are the systems of tacheometry measurements?
The stadia system
The tangential system
Measurement by means of special instrument.


9. Define Sub tense method:
In this method stadia interval is variable. The staff intercept is kept fixed while
the stadia interval is variable lines.


10 State Staff intercept:
The difference of the reading corresponding to the top and bottom stadia wires.


11. What are the merits and demerits of movable hair method?
Merits:
Long sights can be taken with greater accuracy than stadia method
The error obtained is minimum
Demerits:
The computations are not quicker
Careful observation is essential


12. Define Analytic lens:
Analytic lens is an additional lens placed between the diaphragm and the
objective at a fixed distance from the objective. This lens will be fitted in ordinary transit
theodolite. After fitting this additional lens the telescope is called as external focusing
analytic telescope. The purpose of fitting the analytic lens is to reduce the additive
constant to zero.

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==>>PRINCIPLES OF HIGHWAY LOCATION<<==

==>>LOCATION ==>>GEOMETRICS==>>DRAINAGE<<==

Highway location involves the acquisition of data concerning the terrain upon which the road will traverse and the economical siting of an alignment. To be considered are factors of earthwork, geologic conditions, and land use. Geometric design principles are used to establish the horizontal and vertical alignment,
including consideration of the driver, the vehicle, and roadway characteristics. Design of parking and terminal facilities must be considered as they form an integral part of the total system. Since the new highway will alter existing patterns of surface and subsurface flow—and be influenced by it—careful attention to the design of drainage facilities is required....

==>>
PRINCIPLES OF HIGHWAY LOCATION


The basic principle for locating highways is that roadway elements such as curvature and grade must blend with each other to produce a system that provides for the easy flow of traffic at the design capacity, while meeting design criteria and safety standards. The highway should also cause a minimal disruption to historic and archeological sites and to other land-use activities. Environmental impact studies are therefore required in most cases before a highway location is finally agreed upon.

==>>>

The highway location process involves four phases:

==>> Office study of existing information
==>> Reconnaissance survey
==>> Preliminary location survey
==>>Final location survey

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==>>SOIL SURVEYS FOR HIGHWAY CONSTRUCTION<<==

                   ==>>SOIL SURVEYS FOR HIGHWAY CONSTRUCTION<<==
==>>


Soil surveys for highway construction entail the investigation of the soil characteristics on the highway route and the identification of suitable soils for use as sub base and fill materials. Soil surveys are therefore normally an integral part of preliminary location surveys, since the soil conditions may significantly affect the location of the highway. A detailed soil survey is always carried out on the final highway location. The first step in any soil survey is in the collection of existing information on the soil characteristics of the area in which the highway is to be located. Such information can be obtained from geological and agricultural soil maps, existing aerial photographs,and an examination of excavations and existing roadway cuts. It is also usually
helpful to review the design and construction of other roads in the area. The information obtained from these sources can be used to develop a general understanding of the soil conditions in the area and to identify any unique problems that may exist.The extent of additional investigation usually depends on the amount of existing information that can be obtained. The next step is to obtain and investigate enough soil samples along the highway route to identify the boundaries of the different types of soils so that a soil profile can
be drawn. Samples of each type of soil along the route location are obtained by auger boring or from test pits for laboratory testing. Samples are usually taken at different depths down to about five feet. In cases where rock locations are required, depths may be increased. The engineering properties of the samples are then determined and used to classify the soils. It is important that the characteristics of the soils in each hole
be systematically recorded, including the depth, location, thickness, texture, and so forth. It is also important that the location of the water level be noted. These data are then used to plot a detailed soil profile along the highway

==>>Geophysical Methods of Soil Exploration

Soil profiles can also be obtained from one of two geophysical methods of soil exploration known as the resistivity and seismic methods.

              1==>>Resistivity Method


The resistivity method is based on the difference in electrical conductivity or resistivity
of different types of soils.


              2==>>Seismic Method

The seismic method is used to identify the location of rock profiles or dense strata

underlying softer materials..

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==>>Traffic Volumes on HIGHWAY==>>

                                   ==>>Traffic Volumes on HIGHWAY<<==

==>>

No intersection can be properly designed without first obtaining accurate traffic counts and reliable projections for the design year of the project. Traffic counts are best determined from actual field counts, including all turning movements, and are broken down by vehicle type. Vehicle types are divided into two groups.The first group includes passenger cars and type A commercial vehicles (pickup trucks and light delivery trucks not using dual tires).The second group includes type B commercial vehicles (tractor, semitrailer, truck-trailer combinations) and type C commercial vehicles (buses, dual-tired trucks with single or tandem rear axles).Adjustments are made to field counts to allow for day of the week, month of the year,
time of day, and other site-related factors that may have a significant effect on the counts. Most urbanized areas have regional planning agencies that either provide or certify the traffic data used in intersection design.

==>>

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==>>BASIC ELEMENTS OF TRANSPORTATION PLANNING<<==

==>>BASIC ELEMENTS OF TRANSPORTATION PLANNING<<==

The transportation planning process comprises seven basic elements, which are interrelated and not necessarily carried out sequentially. The information acquired in one phase of the process may be helpful in some earlier or later phase, so there is a continuity of effort that should eventually result in a decision. The elements in the process are:



=>Situation definition
=> Problem definition
=> Search for solutions
=> Analysis of performance
=> Evaluation of alternatives
=> Choice of project
=> Specification and construction


==>>Situation Definition==>>


The first step in the planning process is situation definition, which involves all of the activities required to understand the situation that gave rise to the perceived need for a transportation improvement. In this phase, the basic factors that created the present situation are described, and the scope of the system to be studied is delineated. The present system is analyzed and its characteristics are described. Information about
the surrounding area, its people, and their travel habits may be obtained. Previous reports and studies that may be relevant to the present situation are reviewed and  additional noise or air pollution will occur if the transportation facility is built. Usually, cost is a major factor, and so the process will include estimates of the construction, maintenance, and operating costs.


==>>Problem Definition==>>


The purpose of this step is to describe the problem in terms of the objectives to be accomplished by the project and to translate those objectives into criteria that can be quantified. Objectives are statements of purpose, such as to reduce traffic congestion; to improve safety; to maximize net highway-user benefits; and to reduce noise. Criteria are the measures of effectiveness that can be used to quantify the extent to
which a proposed transportation project will achieve the stated objectives. For example, the objective “to reduce traffic congestion” might use “travel time” as the measure of effectiveness. The characteristics of an acceptable system should be identified, and specific limitations and requirements should be noted. Also, any pertinent standards and restrictions that the proposed transportation project must conform to should be understood.

==>>Search for Solutions==>>


In this phase of the planning process, consideration is given to a variety of ideas, designs, locations, and system configurations that might provide solutions to the problem. This is the brainstorming stage, in which many options may be proposed for later testing and evaluation. Alternatives can be proposed by any group or organization. In fact, the planning study may have been originated to determine the feasibility of a particular project or idea, such as adding bike lanes to reduce traffic volumes. The transportation engineer has a variety of options available in any particular situation, and any or all may be considered in this idea-generating phase. Among the options that might be used are different types of transportation technology or vehicles, various system or network arrangements, and different methods of operation. This phase
also includes preliminary feasibility studies, which might narrow the range of choices to those that appear most promising. Some data gathering, field testing, and cost estimating may be necessary at this stage to determine the practicality and financial feasibility of the alternatives being proposed.

==>>Analysis of Performance==>>


The purpose of performance analysis is to estimate how each of the proposed alternatives would perform under present and future conditions. The criteria identified in the previous steps are calculated for each transportation option. Included in this step is a determination of the investment cost of building the transportation project, as well as annual costs for maintenance and operation. This element also involves the use of mathematical models for estimating travel demand. The number of persons or vehicles that will use the system is determined, and these results, expressed in vehicles or persons/hour, serve as the basis for project design. Other information about the use of the system (such as trip length, travel by time of day, and vehicle occupancy) are also determined and used in calculating user benefits for various criteria or measures
of effectiveness. Environmental effects of the transportation project (such as noise and air pollution levels and acres of land required) are estimated. These nonuser impacts are calculated in situations where the transportation project could have significant impacts on the community or as required by law.

==>>Evaluation of Alternatives==>>



The purpose of the evaluation phase is to determine how well each alternative will achieve the objectives of the project as defined by the criteria. The performance data produced in the analysis phase are used to compute the benefits and costs that will result if the project is selected. In cases where the results cannot be reduced to a single monetary value, a weighted ranking for each alternative might be produced and compared with other proposed projects.For those effects that can be described in monetary terms, the benefit–cost ratio (described in Chapter 13) for each project is calculated to show the extent to which the project would be a sound investment. Other economic tests might also be applied, including the net present worth of benefits and costs.

==>>Choice of Project<<==



Project selection is made after considering all the factors involved. In a simple situation,for example, where the project has been authorized and is in the design phase,a single criterion (such as cost) might be used and the chosen project would be the one with the lowest cost. With a more complex project, however, many factors have to be considered, and selection is based on how the results are perceived by those
involved in decision-making. If the project involves the community, it may be necessary to hold additional public hearings. A bond issue or referendum may be required. It is possible that none of the alternatives will meet the criteria or standards, and additional investigations will be necessary. The transportation engineer, who participates in the planning process, may have developed a strong opinion as to which alternative
to select. Such bias could result in the early elimination of promising alternatives or the presentation to decision-makers of inferior projects. If the engineer is acting professionally and ethically, he or she will perform the task such that the appropriate information is provided to make an informed choice and that every feasible alternative has been considered.

==>>Specification and Construction<<==


Once the transportation project has been selected, the project moves into a detailed design phase in which each of the components of the facility is specified. For a transportation facility, this involves its physical location, geometric dimensions, and structural configuration. Design plans are produced that can be used by contractors to estimate the cost of building the project. When a construction firm is selected, these plans
will be the basis on which the project will be built.

<<====

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==>> HIGHWAY SYSTEM , NUMBERING AND JURISDICTION<<==

                  ==>> HIGHWAY SYSTEM , NUMBERING AND JURISDICTION<<==

The Transportation Statistics Office coordinates and maintains data on various highway system designations. Federal Aid Systems, the National Highway System, functional classification, and urban boundaries are developed in a cooperative process with local officials and FDOT according to Federal Highway Administration (FHWA) requirements, and approved by FHWA before becoming effective. The SIS and FIHS are designated by FDOT, with input from local governments, highway users, and other interested parties.

State Road numbers are assigned by FDOT, and County Road numbers by the counties (with guidance from FDOT). US and Interstate numbers are approved by the American Association of State Highway and Transportation Officials (AASHTO).

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==>> TRANSPORTING SYSTEM AND ORGANIZATION<<==

==>> TRANSPORTING SYSTEM  AND ORGANIZATION<<==

==>>

The transportation system in a developed nation is an aggregation of vehicles, guide-ways, terminal facilities, and control systems that move freight and passengers.These systems are usually operated according to established procedures and schedules in the air, on land, and on water. The set of physical facilities, control systems, and operating procedures referred to as the nation’s transportation system is not a system in the sense that each of its components is part of a grand plan or was developed in a conscious manner to meet a set of specified regional or national goals and objectives. Rather, the system has evolved over a period of time and is the result of many independent actions taken by the private and public sectors, which act in their
own or in the public’s interest. Each day, decisions are made that affect the way transportation services are used.

==>>
The decisions of a firmto ship its freight by rail or truck, of an investor to start a newairline, of a consumer to purchase an automobile, of a state or municipal government to build a new highway or airport, of Congress to deny support to a new aircraft, and of a federal transportation agency to approve truck safety standards, are just a fewexamples of how transportation services evolve and a transportation system takes shape.

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==>>RECONNAISSANCE SURVEY FOR HIGHWAY LOCATION IN RURAL AREA<<==

==>>RECONNAISSANCE SURVEY FOR HIGHWAY LOCATION IN RURAL AREA<<==

Two methods;==>>

1. ==>>Conventional ground method.
2. ==>>Aerial photography.

1. CONVENTIONAL GROUND METHOD:==>>

In this method a field survey party inspects a fairly broad stretch of land along the proposed alternative routes of the map in the field.
Intensive reconnaissance is very important for highway location in a new country as well as where completes abandonment and replacement of an existing road are planned.

1. Initially help is taken from already available maps, particularly topographic maps of the area so that most promising general route may be laid out for careful inspection on the ground.
2. Once a route selected on the map by crude but rapid survey method, a survey is made along the path   selected on the map.
3. PRIMARY CONTROLS==>> are then established after it which include
   
   1. Terminal of the road and intermediate points through which it must pass.
   2. Single mountain pass if no alternative exists.
   3. Small settlements, for secondary roads.
4. SECONDARY CONTROLS: ==>>Once primary controls are established the secondary controls are then considered which include;
   1. Drainage system.
   2. Mountain passes.
   3. Low points in ridges.
   4. Cost factors such as favorable and unfavorable soil conditions, the number and sizes of structures, the amount of excavation and embankment, alignment and grade.
5. POSSIBLE ALIGNMENT==>>
   1. In mountainous country with well defined summit ranges, there is usually a suitable pass along the drainage on both sides.
   2. The least expensive and frequently the straightest line may lie just above high water in streams often; however, the rise of valley may exceed the maximum permissible grade.
   3. At times a more favorable location lies on the hillside at some height above the stream.
6. MOUNTAIN LOCATION: ==>> On occasion, the route must climb from stream level to an adjoining pass or summit. The road must be long enough to provide for the required gain in elevation at max permissible rate.
7. Depending sooner from the level valley will result in climbing to summit in less grade and moderate curvature.
   Excessive use of switch backs should be avoided.
8. IN SNOW LOCATION: ==>> In sow areas locations should be confined to slopes exposed to the  sun in order to avoid icing on the roadway and ease snow removal problems..

<<==

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