Small scale earthwork mean not more than 1 acre in area and not more than 1 m height in cut and fill depth.
- site clearing
Site clearing by meaning to clear all the bushes,trees weather small or big,all the temporary structure until can see all area from boundary to boundary.Using all type of machine like excavator,bulldozer with lorries to cart out the residual to the dumping site.Maintaining the boundaries line is most important aspect to control.
- soil stripping
The top soil is not suitable for structure to construct on it.The thickness of top soil are depend on the area.Normally the thickness are from 150 mm to 300 mm and all the stripped soil will cart away from the site.Using a scraper or grader machine to strip the top soil.
- survey works
When all the platform is clear,survey work will begin.From spot level to contour level survey and for hill a or valley the gradient for slope also survey and mark.
- cut and fill
Cut by meaning to cut the higher level or hill to the platform level as written in the drawing.Refering to the marking did by the surveyor ,the gradient of the slope is important aspect to check and control.The amount soil will cut is depend on the calculation by designer engineer.Using a excavator and lorries,the production rate will calculate including time to excavate,time to load to lorries,time to transport to dumping site or to the filling area are calculate.This data is important to put in the MOS.This data is important to calculate the overall duration to complete the certain amount of soil to excavate or to cut.
Fill by mean to backfill the valley with certain amount of soil from import earth to get a platform level as per drawing.The process of bankfilling is layer by layer.Each layer 300 mm thickness and compact until get 95% dry moisture content.Each layer after compaction will test and approve can proceed to the another layer.Using tipper lorries,backpusher or bulldozer or big scraper to laying the earth and using a roller to compact the laying earth.The surveryor is stanby to control the level especially the gradient of the slope.
- compaction
The compaction is the most aspect to check and control.There are many type of machine to do a compaction process but the most popular is vibrator roller.The vibrotar roller with sparay water is the machine get the 95% dry moisture content very easily.The old one is the static roller.
- ESCP
Starting from 2000,when MASMA 2000 was introduced by JPS,every earthwork must submit the ESCP plan before approving the earthwork plan.The ESCP plan is purposely to protect the adjacent area form mud flood to the surrounding area and pollute the river.The ESCP contain the earth drain,boundary protection,slope protection,sedimentation tank a mud collection pond before the water will flow to the existing maindrain.All the requirement and drawing are based and refered to this guide line.
Before any earth work to begin,the MOS will submit to the authority with the item as above.
- retaining wall
- rc retaining
- retaining wall by meaning are that a structure that retain an earth at one side.They consists foundation and wall.The foundation is 700 mm to 1200 mm depth into the ground.The important re bar is vertical bar at the back of retain side and at top bar of the footing.The weep holes is the importance aspect to check the spacing between it.
- The factor of safety for sliding,overturning and soil bearing must more than 2.0,The construction of wall must be 1.2m high and continue with the another 1.2 m until to the finished high.
- gabion retaining wall
- one type of gravity wall,the weight of rock will retain the earth at on side from sliding and overturning
- all the factor safety is 2.0
- size of gabion 1m x 1m or 1m x 2m
- arrangement of gabion weather stack one layer ,2 layer until the desired level or dual gabion at one layer and so on until desired level or triple gabion at the bottom and dual at the second layer to third layer until desired level.
- the arrangement of gabion are depend on the design and factor of safety.
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