Surveying TO LOT

Equipment

electronic distance meter

measures distance with an infra red beam and uses target prisms

Surveying

Equipment

electronic level

 same as a laser level except light beam is detected by a sensor

Surveying

Equipment

instrument care

-proper storage

-leave case open to dry out instrument

-triangle frames on hard slippery surfaces to hold tripod legs in place

-when attaching instrument to tripod just snug up screw

-lens spattered with mud should be allowed to dry before cleaning with a soft rag

-pick up instrument by base

-when carrying on tripod ,carry on shoulder with legs pointed forward

-avoid using when vibrating (heavy equipment moving)

SURVEY

Equipment

laser level

red beam of light

SURVEY

Equipment

terms

cross hairs or fixed reticule, stadia lines, telescopic barrel, eye piece, objective lens, focus screw, level bubble, fish eye bubble, level screw, split bubble coincidence bubble, leveling plate, slow motion screw and clamp

SURVEY

Equipment

transit

-set up plumb over grid mark

-aim at target, lock upper and lower plate clamps and press reset key so that the horizontal angle measures 0 release the upper plate clamp and turn the instrument until the desired reading is found, tighten the upper plate clamp and use the tangent screw to fine adjust

PARTS: telescope eye piece..  telescope objective lens.. . telescope focus ring or knob.. .telescope level vial.. telescope clamp..  telescope tangent screw.. . circle level..  plate level vial..  optical plummet.. .vertical circle reader.. .horizontal circle reader.. .upper motion clamp.. lower motion clamp..  upper motion tangent screw.. lower motion tangent screw.. peep sight.. compass.. .23° West of magnetic North.. leveling base.. leveling screws base plate.. alidade clamp

SURVEY

Equipment

water level

-clear plastic hose

-both ends open to atmosphere

-no kinks in hose

-filled with liquid

-no air bubbles in liquid

-gives a constant elevation

SURVEY

Blueprints

Laying out

control points

-corners of lot marked with steel pegs or bronze monuments

-corners of building measured from lot markers and pegged, a nail marks exact location

-batter boards set back 1800 to 2400

-excavation stakes back about 600 to 900 from building line amount of cut marked on each stake

-POB point of beginning

-BM bench mark  (ELEVATION)

- datum point is the original starting point- bench mark value (100 is often used)

-grids

-offsets

-WP working points usually intersection of grids

-elevations: top of slab, top of PL = top of plate, top of wall

-control points

-control lines

-layout as often as possible from the center lines

-HI height of instrument

-FS fore sight

-BS back sight

SURVEY

Laying out

curved lines

-use radius (a POB equal distance from columns) how: draw a chord between  between two points.. ..  bisect the chord.. . pick a point on the bisecting line as the center radius point, the bisected chord is the rise of the triangle, the run is the bisecting line the rakes are the radius lines.. . use trigonometry        

SURVEY

Laying out

level  rods

tapes

- metric broken into 1 cm divisions

-architectural rod is broken in to inches and fractions of 1/8 inches

- the engineers rod is broken into feet 1/10ths and 1/100 ths of a foot

-move the rod through a small arc to get accurate readings

- you can use a fisheye level on a rod

-you can use a target on a rod

-tapes must be adjusted for temperature

- hand movements for communication

fingers above head to plumb rod, finger direction to move rod, hands sweep to mark, wave to move forward or backward

-rod man errors: wrong location of rod, unstable spot, rod not held plumb

SURVEY

Laying out

leveling an instrument

-use the direction of the left thumb to move the leveling bubble using both thumbs in opposite directions

- swing barrel 90 degrees and repeat continue until bubble is perfect

-test the equipment by sighting the same (30 meters apart )two marks from two different stations about 30 meters apart the distances horizontally between the two marks should be the same

SURVEY

Laying out

records

BE METHODICAL BE ACCURATE

 keep records:

-location of   transit

- chains were pulled from what grid line

- methods used in forming grid line

- what POB was used

-what WP was used

-page and revision date of blueprint used

-record unusual events that may effect out comes

SURVEY

Laying out

stadia lines

-take the level rod reading from the top stadia and the bottom stadia subtract and multiply by 100 the result is the distance from rod to instrument

Surveying

Laying out

terms

- stn.. .station, 

BS+.. back sight are added to bench mark to give the height of instrument, 

HI .. .height of instrument, 

FS.. .fore sight are subtracted from height of instrument to give new station elevation,

IS .. . intermediate sight,

ELEV..  elevation, 

TP .. tuning point