Students during your fieldwork you will wear this shirt:
I will teach you how to use the hose level, bar level, transit level, chalk line (pitik), tape measure, make survey pegs, plumb bob, theodolite, basically the skills to build a house.
Fieldwork No. 1
Okay bring the following:
4 units -10 meter rolls of hose level
4pcs - 2"x4"x 10' timber
1/2 kilo - assorted common wire nails (cwn)
1 kilo - 3", 4" concrete nails
4 units - hammer
4 units - saw
4 units - bar level
4 units - pencil
bring your own tape measure (metro) 5m, 7.5m
I will divide the class into four groups.
Our goal here is from the curb we will measure our desired elevation. In this case top of the curb is 0.00. Drive the peg beside the curb. We make sure the peg is upright by aligning it with the bar level. The bubble should be at the center of the marker. Make sure the peg is immovable that is why you have a hammer. Measure 0.50m from the top of the curb with your tape measure and mark it on the peg. Drive another peg at a distance and make it upright. Fill the hose level with water but make allowances. The water should move up and down. Push the bubbles out. One student will pull one end of the hose and place the water level in line with the 0.50m level marked earlier. Another student will get the other end and go to the second peg and set it against the peg. When the hose level at the first peg stops moving, Student One would indicate this to Student Two who will now mark the 0.50m level at the second peg. We now have two marks. To check we will make the second peg our reference point.
Fieldwork No. 2
Okay class bring the following:
4 units -10 meter rolls of hose level
4pcs - 2"x4"x 10' timber
1/2 kilo - assorted common wire nails (cwn)
1 kilo - 3", 4" concrete nails
4 units - hammer
4 units - saw
4 units - bar level
4 units - pencil
4 sheets - 1/4" 4'x8' ordinary plywood
bring your own tape measure (metro) 5m, 7.5m
Our goal is to plot the four corners of the houses. Class you are divided into four houses, House A, House B, House C and House D. Your reference points are the corners of lot marked as A, B, C and D. The perimeter is lined with nylon string tied at the nails. As you can see in the section detail, the peg is pushed in the ground. The nail is then hammered into the peg
Let us have House A as an example. To define points 1, 2, 3, 4 our reference point will be Point A. Measure the distance along line A-D 5 meters and hammer a peg along the nylon string. Using the hose level make it 0.50m from the ground level same level as the corner pegs. The metal claw of the tape measure clings to the nail head. When the peg is leveled hammer a nail to the marked Point 1a perpendicular to line 1-2. We will extend to Line 1-2 later. Measure 15 meters from Point 1a to 4a. Hammer a peg. Level to 0.500. Hammer a nail.
Using the plywood we extend Point 1a to Line 1-2 using nylon string. One student pulls the string, one student uses the tape measure, one student hammers the peg and so on. The plywood is square so we have a right angle, 90 degree angle or a straight line. My instructor Mr. Manalo taught me the use of the 3,4,5 triangle rule where the adjacent and opposite sides form a 90 degree angle and a hypotenuse. We will use this for checking. Measure 5 meters from Point 1a to Point 1, hammer a peg, level to 0.50m. You can approximate the peg but the nail should be accurate. Measure 15 meters from Point 1 to 2. Hammer a peg. Level to 0.50 meters. Hammer a nail.
You get the idea.
Fieldwork No. 3
Okay class bring the following:
4 units -10 meter rolls of hose level
4pcs - 2"x4"x 10' timber
1/2 kilo - assorted common wire nails (cwn)
1 kilo - 3", 4" concrete nails
4 units - hammer
4 units - saw
4 units - bar level
4 units - pencil
4 sheets - 1/4" 4'x8' ordinary plywood
2 units - transit level
2 units - theodolite
8 units - measuring rods
bring your own tape measure (metro) 5m, 7.5m
Our goal is to learn the use of the transit level and the theodolite. The transit level has the same mechanics to that of the hose level which defines elevations. The theodolite does the same work but it also defines horizontal angles. These devices are supported by a tripod. You dig the three legs into the ground to make it stable. In cases of concrete and metal surfaces make sure the tripods do not move.
Calibrate the transit level and the theodolite by centering the three bubbles. Adjust the three legs and the transit level dial to do this.
In this activity, two groups will use the transit level and the remaining two groups will use the theodolite. Later the devices exchange groups.
Now one student will handle the measuring rod. The rod is a graduated measure that extends to 10 meters. It is made of wood and steel thus it does not fold like the tape measure.
Since we will define elevations you can set up anywhere the range of the scope. The transit and the theodolite are like telescopes that you can adjust the sight. The theodolite however when we will define horizontal angles we will set up at strategic locations.
Surveying with the transit level, theodolite and even the total station involves computations. Okay to set the pegs at 0.50m level same as our reference Point A we will set the measuring rod against the peg at Point A. Make sure the bubbles are at the center. Sight the numbers on the scope. The field is uneven okay so the elevation will not be the same for all. Get a notebook and list the measurements. At Point A we get two measurements - the 1.10 at the level of the transit level and the 0.40 at the top of the peg. 1.10 minus 0.40 equals 0.70. Sight the measure on Point 3 we get 1.35. 1.35 minus 0.70 equals 0.65. Hammer the peg at Point 3 until it reaches the 0.65 mark of the measuring rod.
The transit level costs 18,000 pesos while the theodolite 90,000 pesos that is why I asked the PLM Civil Military Training (CMT) Office to deploy us four cadets to protect the equipment including handling and storage.
You get the idea.
Fieldwork No. 4
Okay class bring the following:
4 units -10 meter rolls of hose level
4pcs - 2"x4"x 10' timber
1/2 kilo - assorted common wire nails (cwn)
1 kilo - 3", 4" concrete nails
4 units - hammer
4 units - saw
4 units - bar level
4 units - pencil
4 sheets - 1/4" 4'x8' ordinary plywood
2 units - transit level
2 units - theodolite
8 units - measuring rods
4 units - plumb bob
bring your own tape measure (metro) 5m, 7.5m and surveying notebook
Our goal is to learn how to define points using the theodolite. The angles are adjusted in the dial. As we said in this endeavor we must place the theodolite at strategic angles. Our benchmark (BM) is from the sidewalk. It is marked by the City Surveyor as a nail hammered in the pavement and encircled with paint. The City Surveyor has the details of the BMs around the city, its elevation, coordinates and distances to other BMs.
The theodolite is positioned directly above the nail at BM. There is a scope downward that you must center the nail. That is aside from calibrating the three bubbles okay. You need patience in this work. In older models of the theodolite they have the plumb bob instead but the same mechanics. You place the point of the plumb bob directly above the nail as close as you can get.
Okay you now ready to sight from BM. You can define Point A using the 45 degree angle and the distance 7.07 meters. From A to 1, it is better we get our reference points from the existing Line A-B and Line AD. Remember we are positioned now at Point A we get to check if the site is square meaning is it built at right angles. Measure A to 1a to 4a. Hammer the pegs, level to 0.50 and hammer the nail. Set up at Point 1 and define Point 2, 3, 4.
You get the idea.
Fieldwork No. 5
Okay class bring the following:
4 units -10 meter rolls of hose level
4pcs - 2"x4"x 10' timber
1/2 kilo - assorted common wire nails (cwn)
1 kilo - 3", 4" concrete nails
4 units - hammer
4 units - saw
4 units - bar level
4 units - pencil
4 sheets - 1/4" 4'x8' ordinary plywood
2 units - transit level
2 units - theodolite
8 units - measuring rods
4 units - plumb bob
12 rolls - nylon string (batak)
bring your own tape measure (metro) 5m, 7.5m and surveying notebook
Our goal is to learn how to make grid lines using pegs. I advise you install continuous pegs to make it stable. The horizontal peg is adjusted to 0.50m level, the level we get from BM 0.00 at the sidewalk. That means our peg is 0.50m higher than the sidewalk. We are building a house okay so refer to the footing and column schedule. We measure 2.00 meters from the edge of the footing where we install our pegs.
The perimeter of the lot is fenced so we have two sides that we can hammer our horizontal pegs. We hammer stakes on the other two sides to support horizontal pegs. We define the gridlines using the equipment we have discussed earlier. We mark gridlines GL A, GL B. GL 1 and GL 2. We check the squareness of our work with the theodolite. We can also use the 3, 4, 5 triangle rule and the plywood. See diagram.
We will excavate to define the location of our footing. We make allowances of 0.10m on the side of the footing. We do that by offsetting from the gridlines. The distance from GL A is 0.70/2 = 0.35 + 0.10 = 0.45. We measure 0.45m from GL A. See diagram. The excavation lines are marked.
The purpose of tying gridlines from peg to peg (batak) is to transfer the coordinates down. We will use the plumb bob to do this. But first we excavate to desired elevation where we gonna concrete the footing.
The bottom of the footing is approximately 0.60m from NGL but we will have 0.10m of gravel bedding. The gravel layer prevents water to come up through capillary action. We pour another layer 0.05m of lean concrete so that our footing has uniform size and we can mark our coordinates in the surface of the lean concrete.
That would be 0.60 + 0.10 + 0.05 = 0.75m but we will excavate down to 0.60 level only. We will compact the soil down to the 0.75m level by tampers and timber.
Pull the nylon string at the GL A from end to end of the pegs. Measure the elevation using the measuring rod from the ground to the nylon string approximating the center of the footing pit. As shown in the diagram, let us say it measures 0.65. Thus 0.65 + 0.60 = 1.25 is the reading of the measuring rod at the bottom of the footing.
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