Untitled Quiz

Podcast Beta

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is the frequency of recording on routes having a speed above 110 kmph and up to 130 kmph?

Once in 12 months

Once in 6 months (correct)

Once in 9 months

Once in 3 months

What is the threshold value of vertical acceleration for Loco Cab floor?

0.10 g

0.25 g

0.15 g

0.20 g (correct)

On which routes is the frequency of recording once in 4 months?

Routes having speed above 160 kmph

Routes having speed above 130 kmph and up to 160 kmph (correct)

Routes having speed above 110 kmph and up to 130 kmph

Routes having speed above 100 kmph and up to 110 kmph

What is the threshold value of lateral acceleration for Passenger Coach Floor?

0.15 g Signup and view all the answers

What is analyzed in Oscillograph Car results?

Vertical and lateral accelerations Signup and view all the answers

What should be done at locations with peaks above threshold values?

The track should be attended to Signup and view all the answers

What is the purpose of Oscillograph Car recordings?

To check the condition of the track Signup and view all the answers

What is an 'active patch' as per Oscillograph Results?

A section of track with excessive oscillations Signup and view all the answers

What action should be taken when a spot/block exceeds track parameter limits and acceleration peak limits set as UML?

Immediate speed restrictions should be imposed Signup and view all the answers

When should speed restrictions imposed due to UML exceedance be relaxed?

After suitable attention/maintenance of track at concerned location Signup and view all the answers

What should be done with blocks requiring Need Based Maintenance based on laid down SD based NBML?

They should be attended within a reasonable time Signup and view all the answers

What should be done with isolated spots identified using offline software or through TMS?

They should be attended within a reasonable time Signup and view all the answers

What is the gap within which two successive NBML locations in block sections/yards should be tamped?

200 m Signup and view all the answers

What should be done while attending an NBML block in a yard with a turnout?

The entire turnout should be tamped Signup and view all the answers

What is the basis for identifying blocks requiring Need Based Maintenance?

Both SD based NBML and Peak based NBML Signup and view all the answers

What factors should officials responsible for maintenance consider while planning deployment of maintenance resources?

Both magnitude of defects, cause of the defect, and traffic density, maximum permissible speed Signup and view all the answers

According to the Track Quality characterization, which of the following indices are computed for each block of 200 m?

Both Unevenness Index and Alignment Index Signup and view all the answers

What is the length of the short chord for calculating ALI1?

9.0 metre Signup and view all the answers

What is the formula for calculating Alignment Index on short chord (ALI1)?

((SD - (SDNTL - ALL - 1)) - ((1.3 × SDM - ALL - 1))) Signup and view all the answers

What is the purpose of maintenance units as per Para 523?

To take action for maintenance Signup and view all the answers

What is the formula for calculating Unevenness Index on short chord (UNI1)?

((SD - (SDNTL - UN - 1)) - ((1.3 × SDM - UN - 1))) Signup and view all the answers

What is the length of the long chord for calculating ALI2?

15.0 metre Signup and view all the answers

What is the purpose of calculating Alignment Index and Unevenness Index?

To compute the Track Quality Signup and view all the answers

What is the block length for which the Track Quality indices are computed?

200 m Signup and view all the answers

What is the need-based maintenance limit for unevenness (UN-1) for speeds above 100 Kmph and up to 110 Kmph?

SD-3.8 mm Signup and view all the answers

What is the planned maintenance limit for alignment (AL-2) for speeds above 100 Kmph and up to 110 Kmph?

SD-4.1 mm Signup and view all the answers

What is the urgent maintenance limit for gauge (mean gauge over 200 m section) in a straight section for speeds above 100 Kmph and up to 110 Kmph?

-10 mm to +12 mm Signup and view all the answers

What is the need-based maintenance limit for twist (TW-1) for speeds above 100 Kmph and up to 110 Kmph?

7 mm/m Signup and view all the answers

What is the planned maintenance limit for unevenness (UN-2) for speeds above 100 Kmph and up to 110 Kmph?

SD-5.4 mm Signup and view all the answers

What is the urgent maintenance limit for gauge (isolated defects) in a curve with a radius less than 440 m for speeds above 100 Kmph and up to 110 Kmph?

-7 mm to +20 mm Signup and view all the answers

What is the vertical and lateral acceleration peak for speeds above 100 Kmph and up to 110 Kmph?

0.30 g Signup and view all the answers

What is the planned maintenance limit for alignment (AL-1) for speeds above 100 Kmph and up to 110 Kmph?

SD-2.5 mm Signup and view all the answers

What is the speed in kmph at location 146/1-2?

100 Signup and view all the answers

What is the type of location at 149/7-8?

Br Signup and view all the answers

What is the total length of the section in km?

232 km Signup and view all the answers

What is the vertical acceleration g at location 149/7-8?

0.35 Signup and view all the answers

What is the date of recording in Statement 'B'?

22nd March 2018 Signup and view all the answers

What is the lateral acceleration g at location 151/8-9?

0.24 Signup and view all the answers

What is the section of the track in Statement 'B'?

BPQ—KZJ (km 367- km 135) Signup and view all the answers

What is the speed in kmph at location 160/7-8?

110 Signup and view all the answers

Study Notes

Track Quality Parameter Indices

Parameter indices are computed for each block of 200 meters to characterize track quality.
Two types of indices are used: Unevenness Index (UNI) and Alignment Index (ALI).
UNI and ALI are calculated on both short and long chords.

Alignment Index (ALI)

Calculated using the formula: ALI = 100 × e × (SD - ((SDNTL - ALL - 1) - ((1.3 × SDM - ALL - 1)))
ALI is calculated for both short and long chords (ALI1 and ALI2).

Unevenness Index (UNI)

Calculated using the formula: UNI = 100 × e × (SD - ((SDNTL - UN - 1) - ((1.3 × SDM - AUN - 1)))
UNI is calculated for both short and long chords (UNI1 and UNI2).

Maintenance

Maintenance units should take action according to the maintenance schedule outlined in Para 523.
Frequency of recording depends on route speed:
- Above 110 kmph and up to 130 kmph: once in 6 months.
- Above 130 kmph and up to 160 kmph: once in 4 months.

Analysis of Oscillograph Car Results

Vertical and lateral accelerations above threshold values are separately counted.
Threshold values are:
- Loco Cab floor: 0.20 g in vertical and lateral modes, and 0.30 g for locos with single stage suspension.
- Passenger Coach Floor: 0.15 g in vertical and lateral modes.

Reports and Interpretation of Results

Results are given in Annexure 5/1 under the following heads:
- Station Yards
- Other than Station Yards (Isolated locations)
- Active continuous stretches

Use of Oscillograph Car Recordings

Threshold values of acceleration are used to attend to track defects and ensure good riding quality.
Efforts should be made to find out if defects are occurring in an active patch, which may lead to excessive oscillations.

For speeds above 100 kmph and up to 110 kmph, planned maintenance limits and need-based maintenance limits are outlined.
Unevenness, alignment, and gauge parameters have specific limits and thresholds for maintenance.

Action to be Taken Based on TRC Results

Action to be taken on exceedance of UML:
- Spots/blocks exceeding track parameter limits should be noted, and speed restrictions should be imposed.
- Suitable attention/maintenance should be carried out to relax speed restrictions.
Action to be taken on exceedance of NBML:
- Identify blocks requiring need-based maintenance using offline software or TMS.
- Attend to these blocks and isolated spots within a reasonable time to maintain good ride quality.

Oscillograph Results

Statement 'B' outlines the results in places other than station yards.
Statement 'C' outlines the results in yards.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.