Construction scheme of the hottest earth excavatio

Earthwork excavation construction scheme

in order to make the earthwork completed on schedule with high quality, the project department decided to adopt the following scheme for earthwork construction after discussion

1. Construction preparation

surveying and setting out and protection of surveying pile points

(1) before foundation pit excavation, all red line piles and building positioning piles in the site shall be measured and approved by the municipal planning department. Clarify whether the red line and the positioning pile have displacement during the pile foundation construction stage. If there is displacement, the planning department, the design unit and the construction unit should be consulted to study the treatment plan

(2) make positioning marks for the roadside roads and temporary facilities in the site for observation

(3) before foundation pit excavation, the lime line at the upper and lower openings of foundation pit excavation shall be measured and set out according to the construction drawings, the slope of foundation pit excavation and the approved axis pile

(4) therefore, before the excavation of the foundation pit, it is difficult to complete all the axes within the excavation scope of the foundation pit by relying on their own resources and capabilities. Some major project line piles and benchmarks should be led out of the construction activity area, and iron nails should be nailed and protected after deep driving with square wooden piles

(5) once all the measuring wooden piles and red line points are verified, the project department should assign special personnel to regularly check and recheck them to ensure the accuracy of the red line

2. Preparation of night construction lighting

during foundation pit excavation, power consumption for night lighting:

a all power consumption can be connected from the distribution box equipped on site and raised to the earth excavation area through a portable small electric box

b the night lighting of the whole construction site is illuminated by two 5000W large Sunglasses placed high on steel pipe shelves

c movable lamp racks are used for night lighting within the construction scope. Each lamp rack is installed with 1000W small iodine tungsten lamps, and each two foundation pits are equipped with a lamp rack

d on the site, a certain number of lights, astigmatism lights and warning lights are placed at the grading position according to the situation

3. Foundation pit excavation method

the main construction tools for manual excavation are picks, shovels and crowbars

(1) construction layering (pile position):

pile position. In order to ensure the safety of retaining piles, earthwork should be excavated in layers. The main basis of earthwork excavation layering is:

a foundation pit excavation is very suitable for the production depth of aircraft parts

b the existing reasonable excavation depth

c soil quality, water level and other requirements and practices shall be comprehensively considered

(2) excavation construction slope

according to the data of geological survey report and field observation, the earthwork of foundation works is of class III soil. According to the construction specifications, when the manual excavation of foundation pit exceeds 1.5m, the construction slope ratio is 1:0.33. If the foundation pit is deep, properly consider enlarging the Grading ratio to ensure the safety of construction personnel at the bottom of the pit

(3) earthwork outward transportation

the project department plans to carry out earthwork outward transportation by manual lifting or manual truck

(4) foundation pit drainage

during the foundation earthwork construction, the project department decided to excavate a drainage ditch beside the foundation pit of each axis, with a width of 300mm and a starting depth of 200 mm. The construction was carried out at a slope of 0.5%. In order to ensure the smooth operation of the drainage ditch, the side slope of the drainage ditch was set at 1:0.77. In case of individual high ground during drainage, the manual excavation of 1.1 meter water collecting well is regarded as excessive

4. Determination of slope during segmented excavation:

according to previous construction experience, through the reference of national specifications and construction data of various projects, the slope of earthwork excavation is 1:0.33

precautions for excavation:

a the earthwork excavation of foundation pit must be carried out in strict accordance with the construction scheme, and over excavation is strictly prohibited

b no materials shall be piled around the foundation pit

c in case of large displacement of soil mass during excavation, the excavation shall be stopped immediately, the causes shall be analyzed, and effective measures shall be taken

d the surface water around the pit should be drained in time

e sufficient lighting shall be provided during earthwork excavation, and electricians shall be on duty day and night

(2) erection of the chute of the access ramp under the foundation pit

after the earthwork is excavated to a certain extent, organize personnel to erect the access ramp with bamboo fences, non slip wooden strips and 48mm steel pipes, with a slope of 1:2

(3) earthwork excavation quality requirements and quality assurance measures

earthwork excavation quality requirements

a the allowable deviation of excavation elevation of main part is 15cm

b the allowable deviation of slope grading is 25cm, but the slope shall not be steep

(4) quality assurance measures for earth excavation tepex has been used in the mass production of battery consoles of trucks. Technical preparations and technical foundation work at all levels should be done before the commencement of construction. The construction technicians (foremen) and surveyors should be familiar with the drawings, master the location and size of the on-site measuring piles and benchmarks, and handle the pile and line inspection procedures with the civil engineering representative. Full time surveying personnel shall be allocated for quality control during construction

b the ash line shall be re scattered in time, and the lower line of the foundation pit excavation shall be measured and placed at the bottom of the foundation pit. Timely control the excavation elevation, and ensure that there are no less than 2 white ash points in the 5m fan-shaped excavation working face

c carefully implement the excavation template system, that is, when re excavating the bottom of the slope, workers with good operation skills will continue to excavate after excavating a section, which will be used as a template after passing the inspection of the surveyor or quality inspector. When the construction personnel change shifts, they should hand over the excavation depth, slope and operation methods to ensure the excavation quality

d when the global market requires higher quality products to excavate slopes, try to use the ditch end to excavate, and the excavation center line of the excavator should be aligned with the lower edge line. We should adhere to the operation method of building slopes before digging

f after earthwork excavation, follow up the pouring of concrete cushion in time, and pay attention to the protection of finished products

g conscientiously implement the technical and quality management system formulated by the project department. Technical data shall be accumulated during construction, such as construction diary, design change negotiation, pile inspection, line inspection records, etc

h after the completion of earthwork, as built drawings shall be drawn, and the four civil engineering representatives and quality inspectors shall jointly inspect and evaluate the quality grade of the project

(5) safety requirements and safety assurance measures for earth excavation

a safety disclosure at all levels shall be done well before commencement. According to the characteristics of the project, such as more construction machinery, more coordination work, poor soil conditions and complex soil transportation routes, safety measures are formulated, implemented by employees, and safety activities are carried out regularly

b check whether the retaining facilities are in good condition every day and repair them in time

c when excavating during rain, take anti-skid measures

d the construction site is completely closed. Faucets, drainage ditches and catch basins are set at the gate. When leaving the site, they must be washed clean before leaving the site. It is not allowed to bring sludge out of the door, which will affect the appearance of the city

e when excavating at night, sufficient lighting should be provided

f in order to prevent slope collapse, it is generally forbidden to pile soil on the upper side of the slope. When placing materials on one side of the slope, they should be 1.0m away from the upper edge of the slope, and the stacking height of materials should not exceed 1.5m

g prepare woven bags, straw bags, wooden piles and other things in advance. If the slope collapses locally, the slope toe collapse can be removed

h if the slope is still unstable after the above measures, the consent of the design unit and the temporary management unit should be obtained. Methods such as increasing the slope gradient or strengthening the soil with compaction grouting should be adopted to ensure the safety of foundation pit construction

i in rainy weather, plastic film should be covered on the slope to prevent soil loss on the slope