The main construction methods and technical measures of earthworks
The earthwork backfill works are mainly for the backfilling of the basement manure trough and the backfilling of the garage roof.
6.2.1. Earthwork excavation and backfill process.
6.2.2. Earthwork excavation and backfill material preparation.
Before filling, the quality of the soil and the water content should be checked to see if they are within the control range. The moisture content of soil is generally suitable for holding a clump and flowering on the ground. When the water content is too large, measures should be taken to loosen, dry, air dry, change soil and backfill, mix dry soil or other absorbent materials, etc., to prevent the appearance of rubber soil. If the soil is too dry, it should be sprinkled with water in advance, increase the number of compaction times or use more powerful compaction machinery and other measures. The optimal water content and maximum dry density of the backfill should be determined by test according to the design requirements.
6.2.3. Key points of operation and quality assurance measures.
1.Key points of earthwork excavation operation.
1) Preparation before construction.
In order to facilitate the construction and facilitate the stability of the foundation pit slope, the earthwork excavation should be done before the positioning and setting work, and the foundation pit enclosure unit should be cooperated with the slope layout in a timely manner.
According to the requirements of the foundation pit enclosure drawings, put the excavation edge line along the excavation face of the foundation pit, excavate in layers, reserve 10cm support pile side wall earthwork for manual cleaning, do 300 300 drainage ditch along the periphery of the foundation pit bottom working face, and do 1000 1000 1000 collection wells at the corner.
2) Construction section division and excavation sequence.
Construction drawings for the division of the construction section in the earthwork stage.
2.Key points of earthwork backfill operation.
1) Before filling, the loose soil and garbage and sundries of the foundation pit should be cleaned up, and the base should be leveled.
2) Before paving the soil, the control sign of the horizontal elevation should be done, that is, from the bottom of the foundation pit, the wooden pile is nailed every 1m along the slope upwards, as the control elevation of the thickness of the virtual paving soil layer.
3) The foundation pit backfill should be paved in layers, and the thickness of each layer of virtual paving is 250mm, and the frog tamping machine is used to ram to the middle according to the circular route from the edge of the pit, and rammed 3-4 times. When ramming, it should be tamped and half tamped, tamped and connected, and the lines should be connected, and the ramming should not be leaked.
4) The foundation pit backfilling should be carried out along the perimeter of the building at the same time. Due to the large area of the local lower chamber and the long axis, in order to speed up the backfilling speed, the backfill can be carried out in sections according to the specific conditions of the site, and the flow construction is organized according to the two processes of soil laying and tamping.
5) after each layer of backfill compaction, must be carried out in accordance with the provisions of the specification ring knife sampling, determine the dry density of the soil, if the dry bulk density of the design requirements is not reached, should be based on the test situation, carry out ramming 1 2 times, and then pass the test before carrying out the upper layer of earth-laying work.
6) When the entire earthwork backfill is completed, the data should be sorted. The test report should indicate the type of soil, the soil dry density required by the design, the test date, the test conclusion and the signature of the test personnel.
6.2.4. Quality control and inspection of backfill.
1.In order to make the quality of the backfill of this project meet the design requirements, the quality of each layer of backfill must be inspected. The dry density of soil was determined by ring knife sampling. When the inspection results meet the design requirements, the supersoil can be filled.
2.Foundation pit and indoor filling, each layer of 100-500m2 sampling group, but each layer is not less than a group;The sampling site is in the lower half of each layer after compaction.