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Transport and Road Research LaboratoryCrowthorne Berkshire United Kingdom1990
A users manual for a program to analysedynamic cone penetrometer data
Overseas Road Note 8
Department of TransportOverseas Development Administration
Transport and Road Research Laboratory Overseas Unit
ACKNOWLEDGEMENTS
The work described in this report was carried out in theOverseas Unit of the TRRL. The report is based on atext prepared by Howard Humphreys and Partners,Consulting Engineers. The computer program itself isbased on an original mainframe program written byNeil Howitt and Dr. J. Rolt and modified by TrevorBell of Contract Data Research Ltd. for use onmicrocomputers.
First published 1990
OVERSEAS ROAD NOTES
Overseas Road Notes are prepared principally for roadand road transport authorities in countries receivingtechnical assistance from the British Government. Alimited number of copies is available to otherorganisations and to individuals with an interest inroads overseas, and may be obtained from:
Transport and Road Research LaboratoryCrowthorne, Berkshire, RG11 6AU England
© Crown copyright 1990 Limited extracts from thetext may be produced provided the source isacknowledged. For more extensive reproduction,please write to Head of Overseas Unit, Transportand Road Research Laboratory
CONTENTS
PageINDEMNITY NOTE 1INTRODUCTION 1
1. INSTALLATION INSTRUCTIONS 22. PROGRAM OPERATION 3
2.1 Starting the Program 32.2 TRRL DCP Option List 32.3 How to Enter Data 32.4 Amend/Review Data 42.5 Do not... 42.6 What to do in the Event of a Computer Failure 42.7 Always... 42.8 Command Line 42.9 OK? Prompt 52.10 Recall File 52.11 Save File 52.12 Data Filenames 5
3. PROCESSING DCP DATA 63.1 Introduction 63.2 The NEW Command 63.3 The RECALL Command 73.4 The EDIT Command 73.5 The INSERT Command 83.6 The DELETE Command 83.7 The KILL Command 83.8 The SAVE Command 83.9 The MORE Command 83.10 The OPTIONS Toggle Command 83.11 The ANALYSE Command 83.12 The VIEW Command 9
3.12.1 I/O: Zoom Functions 113.12.2 S/D/E/X: Panning Functions 113.12.3 G: Grid Toggle 113.12.4 V: View Point 113.12.5 P: Print or Plot 123.12.6 Esc: End Graphics 12
3.13 The PRINT Command 123.14 The FILE Command 123.15 The TOL Command 123.16 The Structural Number (SN) Command 13
4 FILE MAINTENANCE 144.1 Introduction 144.2 Assign Data Drive 144.3 Paper Length/Beeper Control 144.4 Enter Printer Controls 154.5 Assign Graphic Devices 154.6 Test Graphics Screen 164.7 Test Graphics Printer 164.8 Specify Graphics Parameters 164.9 Batch Print 164.10 CBR Relationships 17
INDEMNITY NOTE
Note must be taken by all users of this programthat TRRL DCP is not intended to replace normalengineering judgement. The procedures describedin this manual are intended for users who alreadyhave a thorough understanding of DCP analysisand are capable of deciding which method ofanalysis is most appropriate for individualsituations. The user must be aware of thelimitations of the program and, most importantly,that incorrect data input must lead to incorrectdata output. The user should be capable ofassessing the accuracy of any results produced. Nowarranty can be given on the validity of the resultsand the ultimate responsibility for acceptance andsubsequent use of any results lies solely with theuser.
TRRL DCP is the copyright of:
The Overseas Unit of theTransport and Road Research LaboratoryCrowthorneBerkshireUnited Kingdom
INTRODUCTION
TRRL DCP is a program designed to help withthe interpretation and presentation of DCP testresults.
TRRL DCP has been written to operate underMSDOS and PCDOS compatible microcomputeroperating systems. The program is totallyinteractive with `Help' facilities, and is highly user-friendly with rigorous error checking at data input.
Throughout this manual, whenever the user isrequired to enter text in response to prompts fromthe program, the text is denoted thus: [TEXT].Input commands in the form of single keystrokesare denoted: <COMMAND>.
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1. INSTALLATIONINSTRUCTIONS
The TRRL DCP analysis software is contained onan installation floppy disc which MUST beinstalled on the host computer before it willoperate. (i.e. the software will not work from thefloppy disc).
There are three stages of installation. Firstly therelevant files are copied automatically from theinstallation disc to the host computer's hard disc,then the type of computer display and graphicsstandard is specified and finally the data discdrive, printer controls, test graphics, etc aredefined.
The three stages are carried out as follows. (It isassumed that the floppy disc is in drive A and thehard disc is drive C. The appropriate charactersmust be substituted for A and C if other discconfigurations are used.)
Insert the floppy disc in drive A and type:
A: [INSTALL A C] <Return>. This instructioncauses the required files to be copied fromdrive A to a new sub directory named DCP ondrive C. On completion, remove the floppydisc and store safely.
The computer graphics screen must be eitherCGA, MDA, EGA or HERC and will be eitherMONO or COLOUR. To install the graphicssystem type the following sequence: e.g. for aHercules system:
[DCPINST HERC MONO]
An unacceptable combination of graphics andscreen type will result in an error message.
Start the program by typing [DCP]<RETURN>. Press any key to clear the firstdisplay and choose Option 2 (FileMaintenance) from the main option list. A newoption list will appear.
Select Option 1 to specify the data drive (i.e.where data files will be stored). Option 2 to setpaper length.
Options 3 and 4 should already have beenpreset and need not be changed.
Options 5 and 6 should be used to test thegraphics screen and to test graphics on the
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printer. In both cases a standard `test card'should appear.
By <ESC>aping back through the options the userwill leave the program. The software will now befully installed and may be used at any time by typing[DCP] <RETURN>. A data file named TEST isavailable on disc and may be used to demonstrate thescope of the software. This file is referred tothroughout the manual.
Once the program has been successfully installed aback-up copy should be made and stored safely.
2. PROGRAM OPERATION
2.1 Starting the Program
The computer should be started in the normalway. TRRL DCP will be in a sub-directory of thehard disc. To start the program change to the sub-directory, and type [DCP] <RETURN>. Afterloading the necessary graphics devices thecomputer will display the following notice to theauthorised user.
Pressing a key at this point gives access to themain option list.
2.2 TRRL DCP Option List
The user may move around the option list by usingthe left or right arrow keys until the required optionis highlighted with an asterisk. This option
is also shown towards the bottom left-hand cornerof the screen and will be selected if the<RETURN> key is pressed. Alternatively the usermay press the number shown in front of therequired option.
On completion of any option, the user is returnedto this main option list.
If the <ESC>ape key is pressed, the user isoffered the opportunity to end and to return tothe computer's operating system.
2.3 How to Enter DataThe programs operate in an `interactive' style.Questions or requests for information are displayedwithin `fields' on the computer screen andresponses from the operator are made through thecomputer keyboard. Every time an item ofinformation has been entered through the keyboard,the <RETURN> key must be pressed for thecomputer to accept the data, if the data field(spaces between square brackets) has not beenentirely occupied. However, if the response totallyfills the data field the computer automaticallyaccepts the data. For computers with a reversevideo facility, the data field and square brackets areshown in reverse video. The computer will waitindefinitely until a response is entered to a requestand, subject to the conditions above, the<RETURN> key is pressed.
The program displays a series of `pages' on thecomputer screen. The name of the programappears in the top left corner. At the bottom left-hand side of the screen is an `error' line for thedisplay of error messages, while in the bottomright-hand corner of the screen the user is shownwhich key (usually <ESC>ape) to press to end aparticular operation and proceed to the nextlogical step in the program.
The <ESC>ape key may be used at most points inthe program to leave certain pages, either whendata entry is completed or the user wishes to abort.
Also shown at the bottom right hand corner is the`Help' key. On most computers the <SHIFT> and[?] must be pressed simultaneously.
If help is selected a message will be displayed atthe top of the screen which will give further
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information or instructions on how to proceedwith the program. A typical example is:
The program incorporates an error-checkingsystem to ensure that the data entered is logicaland consistent in relation to the data requested. Atthe bottom of the screen is an error line whichwill display error messages in the event of invaliddata being entered.
For example, if a number is being requested andan alphabetic character is entered in error, an`Invalid Data' message will appear as follows andthe correct data must be re-entered.
The invalid data message may appear for manyreasons and will usually be obvious. However, the`Help' system may give some indication of whydata is not accepted.
2.4 Amend/Review Data
At any stage of entering or amending the data asimple editing facility is available. This involves theuse of two keys which are pressed simultaneously toperform each function, one of which is the control<CTRL> key.
<CTRL> + [X] move down to next batch of fields<CTRL> + [E] move back to last field<CTRL> + [D] move right on command line
On most computers, these commands are availableusing the arrow keys on the keyboard. The simplestway to erase data in a complete cell is to enter aspace followed by a <RETURN>. On reviewingdata a <RETURN> skips to the next data field.
2.5 Do Not...The program is equipped with thorough errorchecking routines but there are still a number ofoperations that the user may carry out which wouldhave disastrous consequences but which cannot beoverruled by the program.
(a) NEVER RESET or BOOT the computer while theprogram is in operation. This will re-set the wholesystem with the loss of data.
(b) NEVER open the disc drive doors and remove orreplace discs unless specifically instructed by thecomputer. This may result in a system failure andthe loss of data.
(c) NEVER press the <CTRL> and [C] keyssimultaneously while the program is in operation.This may stop the program and cause the loss ofdata.
(d) NEVER turn the computer off until instructed to doso.
2.6 What to do in the Event of aComputer Failure
If for any reason, there is a failure, it will be fairlyobvious which data has and has not been recordedsuccessfully. If there is any doubt, the back-upcopies of the data should be used to start the datainput session again.
2.7 Always . . .
There is one cardinal rule for any computerisedsystem. ALWAYS make back-up copies of allcurrent data after entering ANY new information.The copying procedure will vary between thedifferent types of computer and reference should bemade to the Operating System manual and Section2.12 for details of relevant filenames.
2.8 Command Line
Throughout the program the user is presented witha command line near the bottom of the screenthus:
If your screen supports reverse video, the currentoption will be shown in reverse video, and willappear to the right of the word `Command'. Toselect options, the user may press the space bar orthe left and right cursor keys, until the desiredoption has been highlighted. To enter the optionthe user presses the <RETURN> key. The usermay also jump to an option by entering the firstletter of the required option. To exit from thecommand line the user must press the <ESC>apekey.
2.9 OK? Prompt
Throughout the program the user will be asked toconfirm that the displayed data is OK with thefollowing message at the bottom of the screen.
The user has three possible responses to thisrequest:
Enter [Y] for yes and continueEnter [N] for no, go back and reviewEnter <ESC>ape for no and quit this operation.
2.10 Recall File
The user may recall data files previously saved ondisc by moving the cursor to the RECALL commandand pressing <RETURN>.
Use of this option will clear any data in memory andload the recalled data. The user has only to enter thefilename. Sub-directories, data drives or fileextensions must not be specified. Alternatively, theuser may enter [DIR] to obtain a list of those fileswhich may be recalled.
2.11 Save File
The user may save data files on disc by moving thecursor to the SAVE command and pressing<RETURN>.
Use of this option will save the data currentlydisplayed to the specified file. If the specified filealready exists it will be overwritten. Note that it isonly necessary to enter the filename and that fileextensions, data drives and sub-directories are not
required. A list of files already saved on disc canbe displayed by typing [DIR].
2.12 Data Filenames
Throughout the program, data files are created andstored on the data disc. [FILENAME] is auser-specified filename of up to 8 characters. Athree character filename extension, [FILENAME].DCP, is automatically given to each data file. Theuser is not required to enter the drive specificationnor the filename extension in response to filenamerequests.
When batch printing a file, a new file isautomatically created with the same filename asthe data filename but with the file extension .FIL.(See Section 4.9).
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Site: Description of the site [20characters]
Section no. Details of the section no. [20characters]
Text: Details of the test no: [20characters]
Chainage: Details of the chainage [20characters]
Direction/lane Details of the direction andlane [20 characters]
Position/offset Details of the position ofoffset [20 characters]
Date: Date of the test [20characters]
Start layer: Description of the surface orupper layer [20 characters]
Condition: Condition of the start layer[20 characters]
Zero error (mm): If, for various reasons whileconducting the DCP test, thereading is not zero at zeroblows the reading should beentered here.
Surf thick (mm): Enter the thickness of thesurface layer in millimetres.This layer will generally be avery hard layer throughwhich a hole has beenchiselled or drilled.
Extens @ line- Here the user should enterthe line number at which anyextension rod was added tothe DCP apparatus. At thispoint the scale reading willhave been recalibrated andthe user will have enteredtwo readings for the samenumber of blows. In theexample below an extensionrod of 400 mm was addedafter 169 blows when thereading was 466 mm. Thenew scale reading is 66 mmafter which the data entrycan continue as normal.
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3. PROCESSING DCP DATA
3.1 Introduction
This option allows the entry of new data as well asthe editing and storage of existing data. Dataprintouts and plots of the DCP curves may also beobtained in this option.
On selecting the 'Process DCP Data' option, thefollowing screen is displayed:
Along the bottom of the screen a menu isdisplayed and these options are explained in turnbelow.
3.2 The NEW Command
The NEW command is used to clear all existingdata and start the entry of new data. If dataalready exists, the user is required to confirm thatthis data is to be cleared from memory as follows:
If data is not to be lost irretrievably it should firstbe saved using the 'save' command as detailed inSection 2.11.
If the user enters [Y] to the 'Current data savedOK?' prompt then the data currently displayed willbe cleared both from the screen and from thememory, and the cursor will move to the first fieldin the table ready for the input of new data.
Once the data has been entered the user should<ESC>ape in the normal way, see section 2.3 and arecalculation message will be displayed. After theprogram has made provision for any extension rodsthe above data input will appear as follows. The useris required to enter yes [Y] to confirm that therecalculation is satisfactory.
Blows/Rdng: Enter the number of blows inthe left hand column and thecorresponding reading ordepth of the DCP probe in thecolumn to the right. Once allthe required data fields havebeen entered, (100 max)<ESC>ape from the Newoption.
The data in each file is split into 3 sections called:
(i) Descriptive data: As the name suggeststhis data describes the site andconditions and is found on the top halfof the screen.
(ii) Test data page 1: These are the blowsand corresponding readings for the first50 data records
(iii) Test data page 2: These are the blows andcorresponding readings for the second 50data records
During data input the screen will moveautomatically to page 2 after page 1 has beenfilled with data. In order to move back to viewpage 1 again, it is necessary to save the file (seesection 2.11) after which it is possible to select theedit facility (see section 3.4) and make anycorrections required.
3.3 The RECALL Command
The RECALL command is used to recall anddisplay a previously saved data file, see Section2.11. This data file will replace any data alreadydisplayed. The user is required either to enter thefilename or to enter [DIR] to produce a list of allexisting filenames. If a filename has already beenspecified for the data shown, its name will bedisplayed in the data box. If the <RETURN> keyis pressed, the filename will default to the displayname.
After the data has been recalled from disc it isdisplayed. Any errors will be displayed as an errormessage to remind the user of invalid data. Thename of the current DCP data file will bedisplayed in the top right hand corner of thescreen, as follows:
The DCP data may then be edited, viewed,printed etc. If the user tries to recall a filewhich does not exist an error message willappear `File not found'.
3.4 The EDIT Command
The EDIT command is used to edit data in anexisting data file. The cursor moves to the site celland may be moved from cell to cell or field to fieldeither by entering modified data or by
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pressing the <RETURN> key. If the only data tobe modified is further down the file then the downarrow key may be pressed to move down until theline to be changed is reached. The <ESC>ape keymay be pressed to end an edit of the particularpage as explained in section 3.2. To move back topage 1 from page 2 it is necessary to follow theprocedure outlined in section 3.2.
If an error exists in the data the user will bereminded by the `Invalid data' message which willappear at the bottom of the screen. Once EDIT isselected the cursor will automatically go to theline containing the error. When the user<ESC>apes from the EDIT option, the file ischecked for errors and if any are found they aredisplayed in a message as before. The user is thenprompted for yes [Y] or no [N] as to whether hewishes to leave the EDIT option. If no [N] isselected because an error message has beendisplayed by the error analysis, the cursor will goto the box containing the erroneous value.
3.5 The Insert (INS) Command
This command is used to add data either in themiddle or at the end of an existing data set. Theuser is required to enter the line number at whichthe new data is to be inserted.
The existing data is automatically re-displayedshowing blank data boxes for that line. The Editcommand is automatically invoked and the user maymove the cursor to the new line and enter thecompletion of the data entry the <ESC>ape key maybe pressed and a re-calculation and error analysiswill check the integrity of the data.
enters the required line number and presses<RETURN>, he is then asked to confirm thischoice by yes [Y] or no [N] in answer to thequestion `Are you sure?' If [Y] is selected thedeletion is performed.
3.7 The KILL Command
This command is used to delete an entire data filewhich has been recalled and is currentlydisplayed. If the data displayed does not have afilename (i.e. has not been previously saved) thena message `No data file to kill' will appear. Oncekill has been selected the user will be required toconfirm the action in response to the message`Delete (filename)-Are you sure OK? If [Y] isentered the file is removed from the disc, thescreen and the memory.
3.8 The SAVE Command
This option will store data in a user specified discfile, see section 2.11. Once a filename has beenentered the file will be saved with this name. Caremust be taken not to give the file the same name asone that already exists as this will overwrite the oldfile without any warning. If the user types [DIR] fora filename a list of all existing filenames willappear on the screen. However, if the <ESC>ape ispressed the save option will be abandoned but thedata will remain on the screen, so that SAVE can bereselected if necessary.
3.9 The MORE CommandOnce a file is recalled to the screen the first 50 sets ofdata on page 1 are displayed. The MORE optiondisplays the second 50 sets of data on page 2. If theMORE option is selected again the first 50 sets of dataare returned to the screen.
3.10 The OPTIONS Toggle Command
This command displays a second menu as shown.
3.6 The Delete (DEL) Command
This allows the user to delete a line of data andautomatically moves all the succeeding data up to fillthe place of the deleted line. The user is prompted forthe line number by the following:
The data will be re-displayed and re-calculated tocheck that the new data is valid. When the user
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These menu options are selected in the samemanner as described in section 2 i.e. by entering thefirst letter of the option required or by moving thecursor and pressing the <RETURN> key. Thismenu also has an OPTION command which willtake the user back to the first menu.
3.11 The ANALYSE CommandThis option calculates layer thickness and CBRvalues for the data entered, the processed dataappearing on the screen thus:
When the user selects ANALYSE, the programidentifies layer boundaries in the material based onthe rate of penetration, which is an indicator of thematerial strength. The sensitivity of this routine canbe adjusted by changing tolerances and the EM value(see section 3.15).
The results table displays the strength, CBR andthickness of each of the layers identified by theprogram. The layers are zones of constantpenetration rate within the given tolerance and areshown graphically in Figure 3.1.
Transition zones are defined between layers when thegradient of the blow/penetration curve changesgradually over a certain depth thus not permitting thepositioning of a distinct layer boundary.
A bracketed CBR value may appear next to thecalculated CBR value for a layer when the calculatedvalue is very high. In these cases the bracketed valueis suggested as being more realistic for analysispurposes.
The formula used for the CBR calculation isdisplayed beneath the table (see Section 4.10).
3.12 The VIEW Command
The VIEW command is used to display analysed datain graphical form on the screen or to plot it on aprinter or plotter.
When VIEW is selected the following menuappears on the screen:
These options perform the following plots.
(i) Blow-pen: Plots blows versus penetration,(mm) see figure 3.2.
(ii) mm-blow: Plots a histogram of thepenetration rate in mm/blowversus depth in mm. Noboundaries are drawn todistinguish the individual layersbut they may be identified by the`steps' in the plot, see figure 3.3.This plot is useful for assessingthe boundary positions chosen bythe program.
(iii) CBR: Plots a histogram of CBR versusdepth, see figure 3.4.
(iv) All: Plots all the above on onedrawing, see figure 3.5.
The format of the initial graphics display isselected automatically. A scale is fixed so that thecomplete plot can appear on the computer screenwith a superimposed grid. Thereafter a number ofgraphics functions may be used.
A command line listing the various graphicsdisplay options is located at the top right handcorner of the screen. Each function is selectedsimply by typing the appropriate characters.
Figure 3.1
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Figure 3.2 Blows versus penetration curve
NOTE: Beware, on the CBR scale values are showngetting smaller as you move along the "x" axis.
Figure 3.4 California Bearing Ratio versusdepth
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Figure 3.3 Penetration rate versus depth
Figure 3.5 Combination of Figures 3.2,3.3, and 3.4
3.12.1 I/O: Zoom Functions
The I and O zoom functions allow a zoom-in orzoom-out on the current plot. Two rates of zoomingare available. Pressing the [I] or [O] keys will zoomslowly, each step being 0.1 times the original scale,but zooming can be speeded up by pressing the<CTRL> key simultaneously which doubles thezooming rate. After using [I] or [O] the new zoomlevel is shown in the top left-hand corner of thescreen and, in the case of [I], a dotted box will showthe portion of the plot which will be displayed fullscreen when [V] (View) is pressed.
Normally, if a zoom-in is required, CTRL [I] willbe used to zoom-in the large steps and then [I] forfine adjustment.
A maximum zoom level of 500 (500 times theoriginal plot) is the limit for zooming in, and 0.2for zooming out.
3.12.2 S/D/E/X: Panning Functions
[S], [D], [E] and [X] may be used to pan a newplot to the left, right, up and down, respectively.(It should be noted that these are the same as theWordstar cursor movement keys). On somecomputers, the arrow cursor keys will achieve thesame effect.
The panning functions will normally be used afterzooming-in to position the window of the newplot as required.
Two panning steps are available. A `fine'movement using the [S], [D], [E] or [X] alone anda `coarse' movement using <CTRL> with [S], [D],[E] or [X].
Panning appears as follows and the new plot may bedisplayed by pressing [V] as before.
3.12.3 G: Grid Toggle
[G] may be pressed to apply/remove a gridoverlay: it acts as a toggle.
3.12.4 V: View Plot
To view a plot on screen, press [V]. This wouldnormally be used after zooming or panning andthe new plot would be of the zoomed/pannedwindow.
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3.12.5 P: Print or Plot
The currently displayed plot of the new window, ifzooming or panning has been carried out, may bereproduced on a printer or plotter by pressing [P].The computer screen will clear and a `PreparingGraphics Image' message will appear. Oncompletion of printing or plotting, the current plotwill be re-displayed on the screen.
3.12.6 ECS: End Graphics
The <ESC>ape key may be pressed to endgraphics and to return to the option list orCommand line.
3.13 The PRINT Command
This option prints the data in the following format,once the user has checked that the printer is ready forprinting and confirmed this to theprogram.
3.14 The FILE Command
This option writes the data to a print file in ASCIIformat. The format of the file is as follows:
The file name is always the same as the data file name.However, the suffix becomes [FILENAME]. FIL asexplained in section 2.12. These files are used in thebatch print, see section 4.9, and the final printed formatis as shown above.
3.15 The Tolerance (TOL) Command
When the user selects this he will be presentedwith the following screen:
The values E1 to E4 along the bottom of the screenare the tolerances which the program will apply toparticular ranges of penetration/blow gradientduring the analysis phase. These values
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can be changed by the user. The gradient ranges towhich the tolerances are applied are as follows:
E1 - Tolerance for penetration gradients between0 and 3 mm/blow
E2 - Tolerance for penetration gradients between3 and 8 mm/blow
E3 - Tolerance for penetration gradients between8 and 20 mm/blow
E4 - Tolerance for penetration gradients >20m/blow
The EM value at the bottom right of the screen is amultiplying factor which is applied to each of thefour tolerances allowing the user to manipulate thesensitivity of the layer identification routine.
EM x the zone tolerance (El to E4) gives theamount by which the gradient of thepenetration/blow curve is allowed to vary beforethe program decides that a new layer exists.Decreasing any of the zone variables (El-E4)decreases the tolerance in that zone therebyincreasing the number of layers which might bedetected.
Changing the value of EM will affect ALL thezones as follows:
Decrease in EM - Increase in sensitivity-Increase in number of layers
Increase in EM - Decrease in sensitivity-Decrease in number of layers
3.16 Structural Number (SN) Command
For the selection of this option the data file must havebeen analysed (Section 3.10). If this has not beendone an error message `Not yet analysed' will appear.Once analysed this option will display the following:
The user must then choose whether he wishes touse the basic or adjusted structural numberequation.
The basic structural number is similar to the originalAASHTO definition but with the addition of thesubgrade contribution. The adjusted structuralnumber takes account of the way that layercontributions decrease with depth. This option isrecommended whenever the subbase is thick ormultilayered and whenever the exact definition ofthe top of the subgrade is difficult.
Once an equation has been chosen, a prompt willappear under the layer (B/S/G) column. The usermust either press <RETURN>, which leaves thefield blank, or enter
[B] - Base[S] - Subbase
or [G] - Subgrade
to define the pavement layers. The program thenassigns coefficients to the three layer types for use inthe structural number calculation.
Once layers have been defined, the user ispresented with the following screen:
The program now prompts for the structural numberof the surface layer to be input by the user. Thisvalue, if entered, is simply added to the total for theother layers specified as base, sub-base or sub-grade.If any of these layers have not been specified theuser will be prompted to input additional structuralnumbers. If a surface layer is not present the fieldcan be left blank.
Once values have been entered and <RETURN>pressed, the following screen is displayed:
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Structural numbers for selected layers togetherwith a total value for the entire pavement aregiven along the bottom of the screen.
The suggested CBR values in brackets, see section3.10, may change according to the designation of theparticular layer.
4. FILE MAINTENANCE
4.1 Introduction
The file maintenance option allows the user to definewhich data drive is active, the number of lines perpage for the printer paper and the printer controls. Italso allows him to assign the active graphics devices,to test the graphics interface and to specify thegraphics parameters. The definable variables arestored in the file DCPCO and the graphics parameterfile DCPGRF. If the DCPCO file is modified forcolour etc, check the specified parameters.
The following program menu is displayed:
Select the required option using cursor and<RETURN> or the option number. Otherwise press<ESC>ape to return to the TRRL DCP OPTIONSLIST. Each of the options is discussed in turn in thefollowing sections:
4.2 Assign Data DriveThis option allows the current data drive to bereviewed with the following message:
Current Data Drive: [C]
Permissible drive letters are A to Z inclusive. Enterthe new drive letter and confirm that the data is OK,or press <RETURN> to accept the displayed value.Note that sub-directories cannot be assigned to thedata drive.
4.3 Paper Length/Beeper Control
This option allows the length of printer paper to bedefined as lines per page. The number of lines perpage is reviewed with the following message:-
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Number of lines per Page: [66]
Beeper on [Y]
Most printers use a standard 6 lines per inch, socomputer paper of 11 inches in length will be 66 linesper page, while A4 paper will be 70 lines per page.Enter the new number of lines per page and confirmthat the data is OK or press <RETURN> to accept thedisplayed value.
The user may also choose whether to have thebeeper on [Y] or off [N].
4.4 Enter Printer Controls
An explanation of how the printer controls must beentered appears on the following screen:
Having pressed any key the followingscreen reveals the current control settings:
The program does not at present make use of allthe printer controls and they are only included toallow for possible expansion.
The control codes to be used for compressed printon/off and underline on/off will have to be obtainedfrom the printer manual and consist of a series ofASCII values. For each control code, the operator isrequired to enter first the number of ASCIIcharacters in the control sequence and then theASCII values of each of the characters. All ASCIIvalues are entered as decimal integer numbers.Three further controls are specified.
Margin Shift: This provides a means of setting theleft margin on the printout and isspecified in characters, hence a ½ inchmargin at 12 cpi would require aninput of 6 characters.
Backspace If there was no control sequence forUnderlining: underline on/off for the printer,
then it should be set to [N] and ifthe printer is a backspacing`teletype-like' machine thenbackspace underlining can be usedinstead by typing [Y]. If there is acontrol sequence for underlineon/off, or backspace underliningcannot be used then type [N].
Vertica This permits a vertical space to beShift: left at the top of each form/page.
Enter the number of lines to be leftblank at the top of each page.
Having entered/amended the printer controls theoperator is required to confirm that the displayedvalues are to be stored on disc. These values remaincurrent until they are changed again.
4.5 Assign Graphics Devices
This option allows the system to be configured forscreen and/or plotter/printer graphics.
The following screen is presented:
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Only devices which support the Digital ResearchGSX/GEM system may be assigned and theirrespective drivers must be specified and beavailable on the current default disc drive. If thedevices of your system do not support GSX/GEMgraphics then they must be set as not beingavailable and an entry [N] must be made.
Otherwise, if the screen or printer/plotter supportsGSX/GEM graphics, enter [Y].
Having assigned the graphics devices, the useris required to confirm that the data is `OK'before being returned to the menu.
4.6 Test Graphics Screen
Select this option to check the graphics interfaceand to produce a `test card' on the screen. The testcard will contain elements used throughout theDCP options and will be similar to the following:
4.7 Test Graphics Printer
Select this option to check the graphics interface andto produce a `test card' on the printer/plotter. The testcard will contain elements used throughout the DCPoptions. It should be compared with the screen imageto identify any differences between the two devices.
4.8 Specify Graphics Parameters
This option allows various parameters to bemodified to suit the user's system. The followingscreen is presented:
The screen aspect ratio and printer aspect ratiomay be specified. These are values between 0.5and 2.0 to factor the co-ordinates on the relevantaxis to accommodate for distribution. Thesevalues should normally be set to 1.0. However,should the test card show an incorrect aspectratio, then suitable values can be entered tocorrect the distortion.
Two further parameters can be defined. These are:
(i) Graphics text sizeChanges the size of the text of the graphicson both the screen and printer. The requiredsize may be obtained by experimentation.
(ii) Printer BorderThe graphical output on dot matrix printers isoften hindered by the need to plot out a border,so a flag has been introduced. By entering [Y] aprinter border will be included on the plots.Otherwise entering [N] will not print out aborder.
4.9 Batch PrintOnce a data file has been `filed' (see 3.14) it maybe printed as a batch print. Selection of this optionwill display the following:
If the user tries to enter a data file which has notbeen filed an Error message ‘“filename” not filed’will appear at the bottom of the screen.
Once the user has confirmed the printer is ready andcorrectly set, all the files listed will be printed oneafter another, each starting on a new page. It shouldbe noted that the analysed data is not printed belowthe data as in the PRINT command of the ProcessDCP Data options (Section 3.13).
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An example of the format of a file printed by thismethod is found in section 3.14.
4.10 CBR Relationships
This option allows the user to choose whichrelationship between layer strength and CalifornianBearing Ratio to use. There is a choice of thefollowing:-
The four options are
1. Kleyn equation:Log10 (CBR) = 2.632-1.28 x Log10 (Strength)
2. TRRL equation:Log10 (CBR) = 2.48-1.057 x Log10 (Strength)
3. Expansive clay equation:Log10 (CBR) = 2.315-0.858 x Log10 (Strength)
4. User defined equation:This option requires a user entered constantand coefficient in the equation:
Log10 (CBR) = Constant-CoefficientLog10 (Strength)
Printed to the United Kingdom for The Stationery OfficeDd8397622 1/97 C4 51-00 10170
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