Equipment list for Resection and Intersection

For my Intersection and Resection exercise the following are the items of kit I used to complete the task:

• GeoMax Zoom80 Total Station

• Leica Circular prisms

• Three tripods

• Hammer

• PK Nails

• Pegs

• Tape Measure

• Field book

• Leica GPS + Leica GPS Pole

Introduction Statement

Site for the Survey Work: Idmiston, Handcross Road, Plummers Plain, RH13 6NX

Company: Maltby Surveys

Dates: 18/02/2016

Personnel: Diego Alonso - Surveyor

Nerea Buenavida – Assistant

Working on Site:

The work to be carried out on the site involve the use of a total station (Geomax Zoom80) which will be used to measure distances and angles.

All permanent control stations established during the course of the survey will be take form of PK nails hammered into the floor

The survey will be carried out by two personnel from Maltby Surveys.

All survey operations will be carried out within the site boundary of the property to be surveyed, as shown in the aerial image.

All staff involved on this project will wear the appropriate PPE once arriving on site, which is, high visibility jackets and steel toe capped boots.

The project manager can be contacted at the main office located in Haywards Heath. Mobile phone numbers of all site staff can also be obtained from Maltby Surveys main office.

Risk Assessment

Before I carried out my work I had to produce a risk assessment to highlight and eradicate the chances of any accidents/injuries to myself, my colleague, the public, or any of my kit at the specific site. During the process of drawing up my risk assessment I thought of any dangers that could occur and if they were to occur I thought of how I could make sure to the best of my abilities these did not happen. Whilst planning my survey I visited the site and carried out a site walk to plan how to carry out my survey in the safest possible way and also highlight the main risks which could be a problem. As the survey was carried out nowhere near a main road the risks were minimalized instantly. The main risk would be a trip hazard for a member of public either tripping up over a tripod or an instrument box, which is also a risk for dame of kit. The tripods, leave the instrument box underneath the tripod when the instrument was safely placed and screwed on top of the tripod and to also put the stations out the way as best as possible but not that it would affect the survey, e.g not putting the station where I would not be able to see the next station.

Activity / Task Hazard Actionrequired

Responsible Residual risk

General sitework.

Trip hazard oftripods and

boxes.

All stations willbe attemptedto be kept out

the way asbest as

possible.Boxes will be

left undertripods whennot needed.

Surveyor &Assistant.

Members ofthe public

tripping overand injuringthemselves.Surveyor andAssistant bein

injured.

General sitework.

Slipping overin muddy

conditions.

Suitablefootwear to be

worn.

Surveyor &Assistant.

Surveyor orAssistant

being injuredby slipping

over.

General sitework.

Member ofpubblic fallingover a tripod.

All stations willbe kept outthe way asmuch as

possible andalso barrierprotected.

Surveyor &Assistant.

Member ofpublic injuringthemselves.

Damage to kit.

Travelling tosite.

Crossing aroad with kit.

Stop and lookboth ways

twice beforecrossing andensure youu

Surveyor &Assistant.

Danger toSurveyor andAssistant by

getting hit bya car. Damage

are notcarrying too

much kit.Cross inn a

sensible place.

to kit bycarrying toomuch and

dropping it.

Station ThreeStation three is located on the main footpath at the top of the bank in ****** Park, it is located tight to the verge and is just before the main path branches out into three separate directions. The station is marked out using a wax crayon drawing a small white triangle around it and labelling the station with a three so if another surveyor needs to use this station it is easy to find and to beknown what station it is. It is also in the form of a PK nail like my previous station and the nails should all be in the same condition as they were inserted at the same time so if there are other nails in similar place it should be another way of identifying this station. There is 24 hours access to the site so access should not be a problem. There is unlimited free parking on site.

FOTO ST FOTO NAIL

Station TwoStation two was the first station I put in on the site. It is located at the corner ofthe footpath. Station two is up tight next to the verge near two small manholes and opposite a bin. The station is a PK nail in the concrete. I marked it up in wax crayon with a triangle around the station concrete. I marked it up in wax crayon with a triangle around the station and marked it with a number two.

MethodUpon receiving my assignment I chose an area that was suitably large enough for the required process to complete my Intersection and Resection objective. The area had to be large enough to be able to have 6 stations which were a reasonable distance from each other and also an equal distance to reduce errorin this exercise. The stations were marked with PK nails.

The instrument was collimated before the exercise began to reduce the chance of error. I started by travesing the 4 stations of the main loop and when doing this I booked the horizontal angle, the vertical angle and slope distances. I completed his in face left and face right and recorded both on my booking sheets. Upon completing the job and returning to the office I hand calculated the traverse and the face left and right readings were meaned and adjusted.

After completing my traverse targets were set up on all of the stations and I observed a baseline to a known station and the angles were read to 2 station tobe fixed. As with the traverse all results were booked and recorded including the horizontal angles the vertical angles and slope distances. The distances were recorded just as a check so I could compare my calculated distances. The same method was used for all stations and completed in face left and face rightreadings.

As to the resection part of my assignment I set up the instrument on one of theunknown points and the angles and slope distances were read to the 4 known stations in the main loop and booked and recorded. I repeated the process fromthe other unknown point and booked and recorded the angles and slope distance to the 4 stations in my main traverse loop.

On the Intersection, the coordinates of the unknown points were calculated from the main loop stations. There are 3 different techniques to calculate the coordinates of these points which each were used between two stations, these processes are calculated by using the sine rule or the bearings formula or an angles formula. After the coordinates were calculated they were compared and meaned for the final coordinates.

The coordinates were then calculated for one of the stations for the resection part of the assignment. As I read all of the angles in the field I could make a choice for which stations to use in the calculations.

The level for both the unknown points was calculated to complete the coordinates. The level of the station was calculated using the formula: Station Level + Instrument Height + Vertical Index – Target Height. Vertical Index = Hd / Tan ZA. This was completed using the field results from the resection part of the assignment. The method used was the same but the formula had to be rearranged. All of the levels were then meaned and making sure none were

outside the acceptable tolerances.