I started on a tunnel today. Poured the footings for the walls and installed the walls with rebar in the cavaties. The decision on how to construct the roof hasn’t been made yet [Any Suggestions?]. Arched and flat roof are the leaders. Whatever choice is made, it will be dirt and vine covered eventually.
JimC.
Jim, probably the easiest would be to put flat pavers across the top. Besides being easy, if you need to ever get in where you can’t reach or need more than arm room they are easy to dig up and remove. Your portal can be either arched or squared off as that doesn’t matter. Just make sure that you have enough head room that your passengers in the dome cars don’t loose their heads…
Warren
Jim Carter said:If you're not putting a really heavy load on it, you could probably use 2x8x16 concrete capstones.
I started on a tunnel today. Poured the footings for the walls and installed the walls with rebar in the cavaties. The decision on how to construct the roof hasn't been made yet [Any Suggestions?]. Arched and flat roof are the leaders. Whatever choice is made, it will be dirt and vine covered eventually.
My tunnels are under mountains of rock, and some also must support pedestrians on the upper level of the layout. So I make simple, reinforced concrete slabs to cover the tunnels. Here’s how I make them:
On the floor of my garage (a nice level surface), I create a form made of concrete capstones. These are just laid on the floor, not cemented or anything. Over this, I place an unopened plastic trash bag, pressing it down into the form. The concrete won’t stick to the plastic bag.
Next, I toss in a few random pebbles of gravel. On top of them, I place a piece of 1/4" hardware cloth cut to the desired shape. The bits of gravel keep it raised up off the bottom of the form.
Then pour in the concrete, and carefully work it into the hardware cloth so that there won’t be any voids. On large slabs, or where extra strength is required, I’ll add a couple pieces of 3/8" rebar.
After the concrete hardens, simply move the capstones and lift out the slab.
I like the idea of pouring the cement. Make sure there is no place for fine dirt to seep in. The tunnel I just built was straight so I only used pavers and caulked them together with some cement patch. But with that curve and the foot traffic you’ll want a stronger roof.
I forgot to mention, I’ve been laying a piece of asphalt roofing shingles over the joints in the roof of my tunnels prior to covering it over. I figure that’ll do an adequate job of keeping out dust and seepage from between the joints.
Ray ,
It is a good idea , it keeps the rain out of places it shouldn’t be . A dry tunnel is better than a soggy one .
In my area , it is also wise to have a loco that can shift hedgehogs and cats , to save taking the tunnel roof off too often .
Mike
Construction of a curved tunnel [3% grade]. Roof construction was started. The lowest profile possible was prefered and the tunnel will eventually be dirt covered and have vines growing over it. I decided to try a non-traditional arched roof system. First, metal strapping was used to support the plastic sign stock that is to be used under the concrete pour.
Then 1/2 in. mesh wire was formed over the sign stock to act as reinforcing and support for the roof. [brown][As I get older, and the skin on my hands gets more fragile, the little points on the mesh absolutely tore my hands up today.[:(]][/brown]
The concrete will fill into the hollows of the wall blocks and create a single casting for the roof. On the back side, there is an access opening. To provide extra support for the underside of the sign stock while the concrete is poured and setting, two air mattresses - one from each end -will be inflated, until the concrete hardens.
Thanks for the previous suggestions. After the concrete is poured and before the dirt is applied, I will put a layer of asphalt singles over the roof to help keep out moisture. Any more constructive suggestions or advice are welcomed, since I have not seen this type of tunnel construction shown in the forums. JimC.
Looks good so far!
Couldn’t wait three days!!! I pulled the inside braces out today. Sprayed a little paint, stuck in an artificial tree, leaned some rocks against it, [red]and ran some trains[/red]. Portals are on order and should be here next week. Dirt, rocks, and plants still need to be applied.
First I pushed the Streamliner cars through the tunnel without the F3. Then,…Then,…Then,… I hooked up the F3 and FB power car. The tunnel worked perfectly. My baggage car couldn’t get through an R3 switch [outside the tunnel] without the back truck taking the wrong side of the switch, though. Sided that car and everything else went perfectly. Ran it forwards, backwards, slow and fast through the tunnel. Here are a couple of pics showing inside clearances.
Lastly, the Streamliners were sided and the “Where’s the Beef?” consist was hooked up. Again, no problems. Video was taken, both of the passenger consist, and the freight consist, including on-board footage from a gondola. I need to download the video and figure out “U-Tube.” Then I will post the link. JimC.
Grandson Christian, runs the LGB Mikado w/ “Where’s the Beef” stock car & reefer consist [CCW] on Thanksgiving day, through the tunnel, while grand daughter Kelsey, runs the Scientific Toys train on the inside loop [CW].
It was nice to be able to run trains both ways independantly. Tunnel portals still need to be installed. A new reverse crossover was planned today. [:D] JimC
Have you finished the portals yet?
John, The portal on the East end is in place. An Aristo Portal was cut down. The mountain behind and over the tunnel is still incompleted. The reverse loop [not crossover] is completed on the other end of the layout.
The engraved grey stone and large flat rock in front of the tunnel are the memorial resting place to a dear departed pet of the Wife’s. The foreground area will be covered in English Ivy eventually. The tunnel had to built around that area. Thanks for asking. JimC.
The tunnel is finished except waiting for Mother Nature to grow, and grow back, some English Ivey [after I trompled it]where I now have artificial Ivy and in front of the tunnel.
JimC
I thought the tunnel looked pretty good in the snow.
Vidcap from video on YouTube: http://www.youtube.com/watch?v=q5zDiF1H2c4 JimC.
Looks good!..but coooooold…!!