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  • We use all kinds of measuring tools in our everyday lives: rulers, protractors, squares,

  • and tape measures, etc..

  • These work fine for small- and medium-sized projects, but what if we need to layout something

  • big like a road, bridge, dam, or pipeline?

  • Hey I'm Grady and this is Practical Engineering.

  • Today we're talking about one of the civil engineer's most important companions, land

  • surveyors, and we're also going to try a little bit of surveying you can do at home.

  • This video is sponsored by Blue Apron, more on that later.

  • Surveying is essentially the science of taking big measurements, and you've probably seen

  • these guys on the side of the road looking through fancy equipment on a tripod.

  • Just about any civil engineering project starts with a survey to determine the legal boundaries

  • between parcels of property, the location of existing infrastructure, and the topography

  • and slopes of the land.

  • Humans have always had a penchant for building big stuff which means surveying is career

  • full of history and tradition.

  • Behind every wonder of the ancient world was an ancient geometry nerd who laid out the

  • angles and alignments during construction.

  • Surveying is also how we created accurate maps of the continents like the Great Trigonometrical

  • Survey of India, which took almost 70 years to complete.

  • I personally think everyone should aspire to accomplish something in your life that

  • can be prefixed with the wordsgreat trigonometrical.”

  • The ubiquitous tool for a survey is called a theodolite, and it's one job is to measure

  • the angles between two points.

  • Combine those angles with distances from a chain or tape measure, and you can triangulate

  • the location of any point using trigonometry.

  • Modern theodolites, called total stations, can not only measure angles, but distance

  • as well, and they have on-board computers to do the calculations and record the data

  • for later use.

  • When you see a surveyor peering through a funny telescope, it's probably a total station,

  • and he or she is probably sighting a reflector to record the location of a point.

  • That's just scratching the surface of sophistication with modern surveying equipment.

  • With GPS and unmanned aircraft, things can get a lot more complicated.

  • But I've got a few ways you can do your own topographic survey with fairly basic and

  • inexpensive tools.

  • Maybe you've got a drainage issue on your land, maybe you're planning a landscaping

  • project, or maybe you just want to exercise your god-given right to take measurements

  • of stuff and write those measurements down on a clipboard.

  • That's my kind of recreational activity.

  • My goal is to perform a leveling survey of my front and back yard, which is just a way

  • to get the relative topography for an area.

  • I laid out a grid of points on a map of my house and then transferred those points to

  • real life using pin flags.

  • Now I just need to pick my datum or base point and measure the relative difference in height

  • between that point and all the others.

  • I tried a few ways to do this and there are no sines, cosines, or tangents required.

  • First, a sight level which is essentially a combination of a telescope and a spirit

  • level.

  • To use it, first get a buddy or a willing spouse to hold a surveying rod on the point

  • of interest.

  • Now, look through the sight at a surveying rod and raise or lower the end until the bubble

  • is centered on the line.

  • Once it's centered you know that you're looking at a point that is exactly level to

  • your eyes.

  • Simply subtract the height of your eyeline with the height measured on the rod and that's

  • your elevation.

  • It's not a precision technique, but it is cheap and simple which the most you can usually

  • hope for in any part of a home improvement project.

  • The next way I tried is a water level which is literally just a length of clear vinyl

  • tubing filled with a liquid.

  • As long as there are no bubbles or kinks in the line, the free surface at each end of

  • the tube will self-level.

  • I kept one end at my datum a fixed height and measure the height of the water at the

  • other end as I carry it around to each of my points.

  • It's a little more unwieldy but it does have a distinct advantage, no line of sight

  • required.

  • You can use this method around corners or behind trees with no problem, and again, it's

  • a cheap and simple solution.

  • The third method to take a level survey worked best for me: my laser level.

  • Here's the thing: I really like lasers.

  • I relish any chance I get to use them in a constructive way, and this is perfect.

  • The laser level creates a perfect horizontal line that can be used to line up cabinets

  • or tile, but it is also easy read on a surveying rod.

  • You don't need a helper, but you do probably need to wait until dusk unless your laser

  • is really bright, or you have these sweet laser enhancement glasses.

  • This isn't the cheapest solution for a DIY land survey, but it is the fastest one I tried,

  • and it's a tool a lot of people already have.

  • Surveying is one of the oldest careers in the world, and also one of the most important.

  • Why?

  • Because land is important.

  • If you own some, it's probably your most valuable asset, and even if you don't, you're

  • pretty much stuck to it no matter where you go.

  • As a career, surveying is a fascinating mix of legal knowledge, field work, and technical

  • challenges.

  • And since most civil structures are too big for conventional measurement tools, the surveyor

  • is one of the most important companions for the civil engineer.

  • Thank you for watching, and let me know what you think!

  • Thanks to Blue Apron for sponsoring this video.

  • We are still in the process of getting settled into the new house.

  • After a long day installing lights in the workshop or throwing away all the junk left

  • by the previous owner, it has been really nice not to worry about groceries.

  • Blue Apron delivers all the fresh ingredients you need, right to your doorstep, in exactly

  • the right proportions to create delicious recipes at home.

  • If that sounds like something you'd be interested in, the first hundred people that click the

  • link in the description will get 3 meals free with their first order.

  • If you like it, you can continue your subscription, and if you don't, hey, you just got three

  • free meals shipped right to your doorstep.

  • Again, thanks for watching, and let me know what you think!

We use all kinds of measuring tools in our everyday lives: rulers, protractors, squares,

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B1 US survey rod blue apron level height laser

How does land surveying work?

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    F64074065呂揚恩 posted on 2022/03/12
Video vocabulary

Keywords

stuff

US /stʌf/

UK /stʌf/

  • noun
  • Generic description for things, materials, objects
  • verb
  • To push material inside something, with force
essentially

US /ɪˈsenʃəli/

UK /ɪˈsenʃəli/

  • adverb
  • Basically; (said when stating the basic facts)
  • Fundamentally; basically.
  • Relating to the most important aspect of something.
  • In effect; virtually.
  • In essence; when you consider the most important aspects
  • Used to emphasize the basic truth or fact of a situation.
ancient

US /ˈenʃənt/

UK /'eɪnʃənt/

  • adjective
  • Very old; having lived a very long time ago
  • Relating to a period in history, especially in the distant past.
  • Very old; antiquated.
  • Having been in existence for a very long time; traditional.
  • Belonging to the very distant past and no longer in existence.
  • noun
  • A person who lived in ancient times.
infrastructure

US /ˈɪnfrəˌstrʌktʃɚ/

UK /'ɪnfrəstrʌktʃə(r)/

  • noun
  • Basic necessary equipment for a country or region
  • other
  • The basic physical and organizational structures and facilities (e.g. buildings, roads, power supplies) needed for a society or enterprise to operate.
  • The basic hardware and software resources of a system.
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  • The basic framework of a system or organization, especially the hardware and software required for IT operations.
  • The underlying framework or system of an organization.
practical

US /ˈpræktɪkəl/

UK /ˈpræktɪkl/

  • adjective
  • Relating to what is sensible, real or useful
  • (Of a person) good at dealing with difficulties or everyday tasks.
  • Relating to experience, action, or practice; not theoretical or ideal.
  • Suitable for a particular purpose.
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  • Concerned with the actual doing or use of something rather than with theory and ideas.
  • noun
  • A person concerned chiefly with the practice of something; a person with practical skills.
  • A practical exam or lesson.
advantage

US /ædˈvæntɪdʒ/

UK /əd'vɑ:ntɪdʒ/

  • noun
  • A condition or circumstance that puts one in a favorable or superior position.
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  • Benefit or profit gained from something.
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  • other
  • Benefit resulting from some course of action.
  • other
  • To make use of something, especially to further one's own position; exploit.
distinct

US /dɪˈstɪŋkt/

UK /dɪˈstɪŋkt/

  • adjective
  • Clearly different in nature from something else
  • Clearly different or of a different kind.
  • Not the same; different in nature or quality.
  • Clearly noticeable; easily perceived.
career

US /kəˈrɪr/

UK /kə'rɪə(r)/

  • noun
  • Particular occupation in professional life
  • The course of a person's life, especially in a particular pursuit or profession.
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  • An occupation undertaken for a significant period of a person's life and with opportunities for progress.
  • The general course or progression of one's working life or one's professional achievements.
  • A profession or occupation, especially one offering advancement or social prestige.
  • adjective
  • Relating to someone's job
  • Relating to a job or profession that someone does for a long period.
  • Relating to a job or profession that someone does for a long time.
  • other
  • To move rapidly or without control
  • To cause to move rapidly; to promote the development or progress of.
  • other
  • To advance or make progress rapidly
  • To follow a profession as a life's work
  • To move swiftly and in an uncontrolled way in a specified direction.
  • To move swiftly and in an uncontrolled way in a specified direction.
  • To advance in a profession or occupation.
  • To move swiftly and often uncontrollably in a specified direction.
  • verb
  • To move forward very fast and without control
scratch

US /skrætʃ/

UK /skrætʃ/

  • verb
  • To rub your skin with your fingernails to relieve itching.
  • To rub your skin with your nails to stop an itch
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  • To make a small cut or mark on a surface
  • To withdraw from a competition.
  • noun
  • Action of rubbing your skin when itchy
  • A small cut or mark on a surface
  • The beginning or starting point.
  • A shallow mark or cut on a surface.
measure

US /ˈmɛʒɚ/

UK /ˈmeʒə(r)/

  • noun
  • Plan to achieve a desired result
  • A plan or course of action taken to achieve a particular purpose.
  • A certain amount or degree of something.
  • A division of time in music, usually consisting of a fixed number of beats.
  • Tool used to calculate the size of something
  • A standard unit or system used for measuring.
  • other
  • To assess or estimate the extent, quantity, or effect of something.
  • To determine the size, amount, or degree of an object or substance by comparison with a standard unit.
  • verb
  • To determine the value or importance of something
  • To calculate size, weight or temperature of
  • other
  • To take actions to achieve a particular purpose.