1. Land Clearing

2. Aims of cleaning land 1.Remove the obstacles 2.Remove the topsoil

3. Remove the obstacles 1.All vegetation e.g. bushes, scrub 2.Roots of trees and bushes 3.Rocks Then the site will be leveled for construction. Also, the equipment and the service (e.g. water, electricity system and drainage ) will be accessed more easily.

4. Remove the topsoil Topsoil – under ground level about 150mm Since it contains organic material which decomposes, shrinks or swelling by changing moisture content. It will affect he concrete and mortar if it is used for backfilling.

5. The main sequence of clearing technique by using bulldozer

6. Above the ground level all vegetation above ground is removed first, leaving stumps and roots in the ground

7. For small trees (6 Inches or Less in Diameter, and Brush) Operate the bulldozer with the blade Inserts it slightly below the ground level Run straight and digging slightly Cuts, breaks off or uproots most of the trees and roots.

8. For medium trees (6 to 12 Inches in Diameter) set the blade of the bulldozer as high as possible to gain added leverage dozer put the blade lower travels forward again and digs the roots free by lifting the blade

9. For medium trees (6 to 12 Inches in Diameter)

10. As the tree falls, the bulldozer is backed up quickly to clear the roots

11. For large trees (over 12 inches in diameter) It is very difficult and dangerous Because: 1. gently and cautiously the tree for dead limbs that could fall and injure you 2. position the blade high and center it for maximum leverage 3. determine the direction of fall before pushing the tree over

12. For large trees (over 12 inches in diameter) The method is listed below: Opposite the direction of fall, make a cut deep enough to cut some of the large roots.

13. For large trees (over 12 inches in diameter) Cut side 2 and 3 To obtain greater pushing leverage, build an earth ramp. Then push the tree over. As the tree starts to fall, reverse the tractor quickly to get away from the rising root. After felling the tree, fill the stump hole so that water will not be collected in it.

14. For large trees (over 12 inches in diameter)

16. For small to medium area From outside to center –the operator rolls the unwanted materials to the outside and away from the uncut area.

17. For small to medium area From center to outside – the cut materials are rolled to the center.

19. For the slope area The unwanted materials are taken to the windrow at the edge of the slope. It is better to move downward to slope in order to obtain maximum efficiency and reduce fuel consumption.

21. Clearing technique (removing stumps from ground) Clearing blade with stinger is used –Stumps are pushed out form ground –The stinger is designed to be used as a knife –The edge of the blade is used for pushing For extremely large trees 1.cutting the lateral roots around the tree 2.Pushing the tree with the blade raised high to provide leverage

22. Clearing technique (removing stumps from ground) For extremely large trees 1.cutting the lateral roots around the tree 2.Pushing the tree with the blade raised high to provide leverage

23. Clearing technique (removing stumps from ground)

24. Earth ramp is needed on one side of the tree to gain greater pushing leverage

25. References Peurifoy R. L., Schexnayder C. J., Construction planning, equipment, and methods, 6th ed., Mc Graw Hill Newfoundland guidelines for clearing land http://www.gov.uf.ca/agric/clearing_land.pdf Clearing, grubbing and stripping, http://www.adtdl.army.mil/cgi-bin/atdl.dll/fm/5-430-00- 1/CH4.htm#fig4_4 McKay, John Kenneth. Building construction, Volume 4 / J.K. McKay ; Harlow, Essex : Longman Scientific & Technical, 1988. Seeley, Ivor H. Building technology 4th ed. Ivor H. Seeley Houndmills, Basingstoke, Hampshire : Macmillan, 1993

26. Group members Vicky Lam (QS) 50255268 Tina Hui (QS) 50320673