Category: Carrum

The distance between the Patterson River and McLeod Road is not long enough

The distance between the Patterson River and McLeod Road is not long enough to provide train clearance under the road and return to ground level before the Patterson River rail bridge at an incline that would allow trains to run safely.

Understanding the above three arguments from LXRA are false the following are some options available:

Option 1

Rail bridge modified; 2.0% grade

Layout1

Platform starts 106m past McLeod. This will be taken up with the station building(s) positioned at McLeod and ramp. The ramps for trenches at Springvale, McKinnon etc are over 100m long.

 

Rail elevation at the platform = -2385mm

 

 

Using just 2.0% grade; McLeod joining Nepean from its’ current position and with the rail bridge modified.

The distance between the Patterson River (southern pier) and McLeod Road IS LONG ENOUGH to provide train clearance under the road and return to ground level before the Patterson River rail bridge (where boats access) at an incline that would allow trains to run safely.

 

Continue to Option 2.

 

A steeper incline would not meet metro and freight rail standards

LXRA are stating that 2.0% is the maximum incline for the Frankston line.

A relatively new rail section allowing for a trench solution at Ormond and McKinnon which appears to accommodate a storm drain is 2.36%. Obviously, this is a safe operation or it would not have been built by LXRA. Advice from LXRA representatives is that this was a special case and needed special safety considerations and, yes, special safety considerations could again be applied.

A steeper incline CAN meet metro and freight rail standards for safe operation.

Changes to the Patterson River rail bridge would NOT require a closure of the Frankston line for up to six months

A new road bridge connecting Station Street to Station Street over the Patterson River is planned.
This can be used as a temporary rail by-pass whilst any changes to the Patterson River rail bridge are completed.

Carrum temporary rail by-pass
Carrum temporary rail by-pass

Allowing for a safety fence 3m from the by-pass rail track access to properties either side of Patterson River remain unaffected.
This will require a stronger bridge for the train use but any additional height caused by deeper spans can be accommodated with the more lenient road design rules and/or service road use.
And this is working on a two-track by-pass where train schedules will not have to be altered.

But even with a single-track by-pass all trains can be accommodated.

Total by-pass length <500
Metro train length 150
Total to travel 650

Use a temporary by-pass speed restriction to suit track transitions:

Transit use time in by-pass
At 40km/hr ~ time 59 secs
At 50km/hr 47 secs
At 60km/hr 39 secs
Add acceleration 10 – 15 secs

Red figures indicate new schedule
All changes within 2 minutes

A minimum of 3 minutes between
entry to by-pass end

All trains serviced ~ No bussing reqd.

Morning peak

Bonbeach By-pass   Carrum
0600 0601
0606
10 11
20 21
22/24
29 30
33
43/42
44 45
47/48
50 51
55
59
0702 0703
0709
12 13
16
 20/19
21 22
24/25
28
31 32
35
 39
43
 43/45 44/46
49
53
53/55 54/56
59
0804 05
0810
16 17
21
26 27
 33
37 38
43
 46 47
 53
54/55 55/56

Evening peak

Bonbeach By-pass Carrum
1702
1704 1705
12
14 15
 22
25 26
 30
35 36
39 40
44
49 50
53
59 1800
1803
1805 1806
10 11
13/14
21 22
23/25
25/27 26/28
32/31 33/32
33/35
36/37 37/38
44/43 45/44
 45/47
 48/49 49/50
 54
54/56 55/57
1906 1907
10
10/12 11/13
16 17
20 21
24
 26 27
 37 38
39/41
 47 48
54
 57 58

Changes to the Patterson River rail bridge DO NOT require a closure of the Frankston line for up to six months.

Carrum: Lowering the Patterson River rail bridge would NOT impact boat access.

Carrum Boats only use the two mid spans.
Carrum: Boats only use the two mid spans.
The southern span can be lowered without impacting on boat access.
The southern span can be lowered without impacting on boat access.

This effectively increases the distance from the Patterson River to McLeod Road.
Additionally, the vertical gradient transition from level to – 2% (or more) can be achieved over the
mid spans of the bridge improving the effectiveness of lowering the southern span and not impacting on boat clearance.

Rail under road in Carrum

Carrum Station Options for a Trench

LXRA say:
A rail under road design is not possible in Carrum due to:
1. The distance between the Patterson River and McLeod Road is not long enough to provide train clearance under the road and return to ground level before the Patterson River rail bridge at an incline that would allow trains to run safely.
2. A steeper incline would not meet metro and freight rail standards for safe operation.
3. Changes to the Patterson River rail bridge would require a closure of the Frankston line for up to six months, which is not feasible for commuters or freight operators.
4. Lowering the Patterson River rail bridge would impact boat access.
5. Moving the McLeod Road connection further south would increase congestion, reduce traffic flow and move the station 350 metres south away from shops and services.

We will look at each of these points but not in the order given above.

See full responce in PDF document – March 2017 summary of options.

Lowering the Patterson River rail bridge would impact boat access.

Changes to the Patterson River rail bridge would require a closure of the Frankston line for up to six months, which is not feasible for commuters or freight operators.