Deflection

I have been wanting to write about the geology and highway design and construction for several days, and I have not waited to type the best until last the last entry. I might not cover all of the highway issues that I saw, because there would be too much to cover, if I can remember it all.

Scotland is in a glacial till just like Wisconsin is from south of Whitewater to the north. Or from the terminal moraine that runs through Walworth and Rock counties east and west of the Wisconsin Glacier. As for the terminal moraine to the south is the glacial washout and, after the recent high rains, there is no ponding of water to the south. As far as the till to the north, the fields have been cleared of rocks so that the corps could be grown in the rich agricultural soil, with every fence line is filled with rocks. In Scotland, the terminal moraine is in the southern third of England, so that Scotland is in the glacial till. The rocks, for centuries have been removed from the farmer’s fields, but, instead of the rocks being placed in the fence row, the Scots used manual labor to make fences, since they where building fences for centuries before barbed wire was invented. There are an unlimited number of miles of meticulously constructed stone fence. Even after being installed for centuries, the stone fences have no signs of deterioration, like poor soil for foundations. There is no evidence of any freeze/thaw issues moving the walls. These fences do show deterioration from the weather and vegetation growing on the walls.

The soil under the pavement took me a while to understand, since the soil was not acting like the soil that we see in the states, or maybe I should state Iowa with the Iowa gumbo, mainly a soft clay, to build highways on in the state. The Scottish highways have miles of asphalt pavement that has no blemish with over a decade of use, like over 70 percent of pavement area (it would be nice to get this kind of results in Iowa), but there were zones where the asphalt had lost it structural base. To make it more difficult to understand, there was miles of soil curbs (not concrete or asphalt). There was something different going on here, and it took more time to understand. The River Dee is cutting through an old glacial washout that is smooth stones and sand. This is the clue. The natural soil has a thin layer of top soil, and I recon that it is from the short growing season based on the high latitude and this area is on the east side of Scotland. Under the top soil, between the glacial till rocks, is sand. Grading a new highway must have been difficult with all of the glacial rocks that had to be moved and then completed round the rocks that was left under the sand base. But this is not the common sand that we usually find on beaches, since it is cohesive sand. If a person takes a hand full of normal sand and squeezes it, depending on the water content in the sand, it will fall out of your hand when you open your hand, but the cohesive sand is different. If a person squeezes cohesive sand, it will stay in a ball after the hand is opened. Regarding the miles of soil curbs on the edge of the pavement, it is the cohesive sand that maintains their shape, unless too much water stands on the pavement for too long. As for the grade of the pavement, once the compacted sand is placed with asphalt over it, it last without even a crack in for over a decade. This highway maintains its shape until there is a problem with the grade under the pavement. I would suspect that two things can happen: 1) the sand was compacted over unstable soil and the glacial till rocks; and 2) water had inflated under the pavement. With most of the zones of deteriorated pavement being on. the outside edge of the pavement, I would suspect that water had infiltrated in from under the edge of the pavement.

The signing was different than we are use to here in the states. I sometimes wonder if they have standard signing. I am not sure that I remember a stop sign or not, but I do remember a “give way” signs, but I am still not sure which driver is to give way, so I guess that it is the driver that is reading the sign. There are a few different types of signs used for sign intersections. Some of the sign just show the adjacent highway going off to the highway that was being traveled and some of the sign wrote the name of the adjacent highway. There were many different signs used for a curve. Even a slippery when wet sign. Since I was basically in at rural area, it did seem like different signing was used. In some locations, the pavement was only wide enough for one vehicle, so one vehicle would have to find a place to pull over that could be difficult. On the narrow highways with fence and vegetating growing on both sides of the roads, there was mirrors installed on posts on the other side of driveways. It was an experience seeing the signing.

On the main highways, there were arrows in the center of the pavement pointing from the other lane to the driving lane. At first, I thought that these were left over from construction. But, after seeing a few, I was wrong. They are to remind the drivers that drive on the right side of the highway at home to drive on the left side of the highway.

This is about all that I can remember about the geology and the highways. As for those that have been reading my journal entries about Scotland, I will stated that I really enjoyed Scotland. It was so overwhelming with the extreme dedication to manual labor, geology, highways, trails, and history. As I have perviously stated, I can spend more time there without any problems. I am trying to figure out the best way to see Scotland, and, since they do have mini motorhomes for rent, this might the the best way for me to see Scotland, since most of the areas that I want to see are rural.

Roger