Standard sample of work instructions Construction work instructions

Construction technology disclosure record

( ) level construction technology disclosure

Unit project name: Subgrade project pile number: K 31+025—K 5000 Technology Disclosure content: Subgrade filling disclosure card number:

1. Project objectives

1. Quality objectives

All technical indicators meet industry requirements and owner requirements. Ensure 100% project quality rate. We strive to be among the best in terms of quality and progress across the board, ensuring that construction quality reaches excellent standards.

2. Construction period progress target

Strictly implement the construction period requirements signed in the contract, strengthen on-site construction management, and ensure that the remaining construction tasks of the contract section are completed on schedule.

3. Safety objectives

Take effective measures during the construction period to ensure that no safety accidents occur during the construction period.

(Attach page)

Approver: Date:

Reporter: Date:

Recipient: Date:

2. Division of tasks for the construction team

Arrange for three construction teams to carry out construction at the same time. The station numbers are: K31+025-K37+650, the double-side widening section of the old road; K37+650-K42 +650 new line section; K42+650-K5000 old road reconstruction and fill section. Each construction team carried out construction on multiple construction work surfaces in stages and in a cross-over manner to ensure that each sub-project completed its tasks according to the overall construction plan.

1) The personnel and equipment of each construction team must meet the construction requirements, formulate measures according to the construction production plan, adjust resources, and give priority to controlling the quality and progress of the project and the human, financial, material, equipment and other resources of key projects configuration.

2) Reasonably arrange and organize the construction, eliminate the factors affecting rainy days, make full use of sunny days, seize the construction period, grasp the progress, and shorten the controlled time of the process to the shortest time.

3) Strengthen mechanical maintenance, improve mechanical integrity and productivity, and ensure smooth progress of construction and production.

4) Prepare material supply in advance, clear material supply channels, and ensure that material supply does not affect construction.

5) Strengthen quality control, eliminate delays in construction due to quality reasons, conduct careful construction, and produce efficiently to meet excellent engineering standards.

3. Engineering technical requirements

1. Engineering and technical personnel must be familiar with the design drawings carefully and clarify the technical requirements of each section, such as the relationship between each structural layer, single slope of the road surface, and super-elevation of the gentle section. , construction elevation control, roadbed widening section, etc., be aware of it, ensure that the construction line is correct, and guide the construction in a timely manner.

2. When the original conductor points cannot meet the construction requirements, they must be encrypted to ensure that adjacent conductor points can see each other during the entire construction process. It must be closed with the conductor points in the adjacent construction section. Conductor points that hinder the construction must be fixed after retesting and before construction. The fixed piles must be strong and reliable, the pile position must be convenient for setting up instruments, and they must be located outside the construction section.

3. Before the start of roadbed construction, fully restore the center line and fix the main control points of the route, such as turning points, circular curves and

The starting and ending points of the easement curve, as well as the control 100-meter piles and Add piles. When restoring the center line, attention should be paid to

closing the center line with the center of the structure and adjacent construction sections. If any problems are found, the cause should be promptly identified and reported to the engineering department for resolution.

4. The error of adding temporary leveling points must meet the construction accuracy requirements. If it is found that an individual leveling base point is affected by engineering construction, it should be moved outside the influence range and its elevation should be closed to the original leveling point.

5. Engineering measuring instruments must be taken care of and kept to prevent them from being knocked or lost. If the instrument is found to be damaged, the relevant personnel must be held accountable

for responsibility.

6. Before filling the roadbed, engineering and technical personnel should restore the boundary piles and middle piles of the occupied area, and the elevations of all edge

and middle piles of each layer should be calculated clearly and accurately. It is necessary to clarify the 92%, 94%, and 95% compaction range and elevation control of each section. Clarify the filling height and construction content of each section. During specific construction, the elevation and width should be well controlled to avoid problems.

4. Subgrade earthwork construction technology

1. Preparation work

According to the design and specifications and the requirements specified by the supervision, clean up the site and remove any obstructions within the land area.

Remove trees, shrubs, stones, waste materials, garbage, weeds, etc. that obstruct the view, hinder construction and quality, and place the removed weeds and other objects in designated locations, at least 100~300 mm below the original ground. The topsoil inside should also be removed, and the removed humus should not be discarded. It should be neatly stacked between the foot of the roadbed slope and the highway land boundary, or other suitable storage locations, as soil for greening. Investigate the hidden pipelines and facilities within the line and the locations of underground facilities to be buried during construction, and explain them to the construction personnel. The topsoil is removed from the excavation section, and the soil suitable for planting is piled on both sides of the roadbed. The humus soil used for grass planting in the roadbed protection project is processed according to the owner's instructions.

The borrow pit should be planned according to the design. When borrowing the soil, the slope should be 1:1.75, and drainage should be done at the same time. The humus soil on the original ground should not be discarded. It should be neatly stacked outside the foot of the slope or other suitable storage locations. It will be plowed again after the soil field is used up. Construction is carried out using a combination of manual work and bulldozers, loaders, dump trucks and graders.

Before embankment filling, pre-filling treatment will be carried out after the site is cleared. In the remaining filling areas, after the site is cleared, the ground will be leveled with a grader, the holes will be filled, and compacted with a heavy-duty roller to meet the standards required by the owner. Only after self-inspection and supervision approval can the first layer of the roadbed be filled.

2. Temporary drainage of the subgrade

Temporary drainage within the subgrade must be done before construction. For wet areas, vertical and horizontal drainage ditches must be excavated to remove accumulated water and cut off or reduce the groundwater level. . During construction in the rainy season, it is necessary to prevent water accumulation on the embankment. The surface of the filling layer should be appropriately increased in cross slope. Temporary drainage channels should be built on the edge of the road shoulder to facilitate drainage. Pay attention to the weather forecast and roll the roadbed in time to prevent the roadbed filling from being soaked by rainwater. washed away.

3. Subgrade filling

The filling subgrade must be controlled in layers according to the parallel lines of the road surface. The filling operation must be paved in layers and parallel, and mechanical compaction shall be used. The maximum loose paving thickness of the layer should be determined experimentally. For fine-grained soil, it should generally not exceed 30cm. In the K37+650-K42+650 construction section, the lower part of the roadbed is filled with fly ash and edging soil, and the top 40cm of the roadbed seal is 6%-8% lime soil; in the K42+650-K5000 construction section, the roadbed seal is The top 30cm should be made of 6%-8% white lime soil. The earthwork embankment should be filled to the last compacted layer on the top of the road bed. The thickness of the compacted layer should not be less than 10cm. The width of each layer of filler should exceed the design width of the embankment by 20cm on each side to ensure warranty. The edge of the embankment after the slope of the subgrade has been fully compacted and will be leveled after the subgrade is formed. Filling materials of different soil types should be filled in layers, and the number of layers should be minimized. The total thickness of each filling layer should not be less than 50cm.

When the fill height of the embankment is less than 80cm (excluding the thickness of the road surface), the soil base after the original surface cleaning and excavation should be plowed to a depth of 30cm, and then leveled and compacted. The degree of compaction must meet specification requirements.

When the embankment filling height is greater than 80cm, the embankment base must be leveled and rolled before filling, and the compaction degree shall not be less than 85%.

When the natural cross slope or longitudinal slope of the ground is steeper than 1:5, the original ground must be dug into steps. The width of the steps must meet the needs of the paving and compaction equipment operations and should not be less than 1 meter. The top of the step is tilted inward by 2% and then filled.

When widening the old embankment in the K31+025-K37+650 construction section, steps should be dug along the left and right slopes of the old embankment. When the height of the old embankment is less than 2 meters, the old roadside should be removed at one time along the old road shoulder. Slope removal is used to reduce the uneven settlement of the old and new roadbeds. Special attention should be paid to mechanical rolling of the wider parts to ensure qualified compaction and ensure the overall stability of the original roadbed. For roadbed projects connecting structures, avoid endangering the safety and stability of the structures during construction. When building access roads and approach roads within the embankment, new embankments must be filled in according to regulations.

When filling the roadbed with gravel soil, it should be filled and compacted in layers. Before filling with permeable materials, this layer of edging soil must be made first. The width of the edging soil must ensure that the net width after leveling meets the requirements of the construction drawing design. After the permeable materials are spread, they must be compacted together to achieve the compaction. According to the actual standards, the permeable materials after paving must be rolled in time to prevent water evaporation and affect the compaction effect.

The gravel soil filling roadbed shall be constructed according to the type of compaction machinery, number of compaction passes, paving thickness and degree of compaction determined by the compaction test.

4. The subgrade is mixed with ash

Since the subgrade earthwork is filled with clay from the borrow pit, but the soil moisture content in the borrow pit is now high, according to the requirements of the headquarters, Now the earthwork is 100% mixed with ash.

The roadbed ash mixing process method: Purchase quicklime that meets the quality requirements, spread the lime evenly on the overly wet soil, when the excavator digs the soil, stir it several times with the shovel, and mix the lime evenly in the soil. If the soil is too wet, dig it out and pile it up for later use, so that the lime can fully improve the properties of the soil and reduce the moisture content of the soil. Pay attention to detecting the dosage of lime and controlling the moisture content of the soil to meet construction requirements. When filling the roadbed, use a loader to load the soil and dump trucks to transport it to the construction site for paving and rolling.

5. The laboratory shall carry out heavy-duty standard compaction of plain soil and standard compaction of 2%, 4%, 6% and 8% white lime soil, and at the same time make a standard curve for the EDTA titration of lime dosage and specific construction time, conduct detection according to the situation. When testing, the tester first determines the standard compaction of the testing area, then measures the compactness, and clearly records the construction section, location, number of layers and amount of ash, and truthfully reports it to the industry personnel for easy measurement.

6. Treatment of roadbed elasticity and softness

When the roadbed is partially elastic and soft, dig out and discard the elastic and soft part of the roadbed, replace it with materials with appropriate moisture content, and strengthen mechanical grinding after leveling. Press to ensure compaction standards are met.

7. Compaction of roadbed

Before compaction, the fill layer should be leveled and made into a 2%-3% cross slope. The roadbed fill compaction is carried out using a 25T vibratory roller combined with an 18-21 ton roller. The rolling speed should be slow at the beginning, and the maximum speed should not exceed 4 kilometers/hour. When rolling, the straight section is carried out from both sides to the middle and longitudinally forward and backward. The roller is used to roll the road sequentially from the roadside to the middle and from the low side to the high side. Compaction follows the principle of light first and then heavy until the designed compaction degree is reached.

For rolling transverse joints, the overlap is generally 0.4-0.5 meters for vibratory rollers. For three-wheel rollers, the overlap is generally 1/2 of the thick wheel width. For rolling longitudinal joints, the overlap should be 2.0-3.0 meters. To achieve no There is no pressure leakage and no dead corners, ensuring uniformity after rolling. Before paving the next layer, the compaction qualification rate of the previous layer must reach 100%, and the next step of construction can be carried out with the approval of the supervising engineer.

8. Quality inspection

After each layer of earth filling is completed, the sand filling method is used for test and inspection to ensure that the compactness of the roadbed meets the specified requirements.

9. Treatment of joint parts

When the fill embankment is constructed in several working sections, if it cannot be filled at the same time, the sections to be filled first should be left in layers 1: Steps with a slope of 1; if they can be filled at the same time, the length of the overlap must be greater than 2 meters. When the junction of two sections of roadbed is filled at the same time, they must be overlapped and connected in layers, and the connecting length shall not be less than 2m.

10. Subgrade sealing layer

The top sealing layer of the subgrade is 6%-8% white lime soil. According to the moisture content of the soil field, first reduce the moisture content of the soil, and then mix in Sufficient amount of quicklime or slaked lime (fully digested). The amount of white ash should be ensured during sealing construction, and the roadbed surface should have good flatness, cross slope and compaction to ensure that the roadbed deflection is qualified.

When constructing the sealing layer on the top surface of the roadbed, the construction must be done by hanging wires and the elevation should be controlled pile by pile. If necessary, the elevation and control points should be encrypted to ensure the accuracy of the elevation of the road bed. Manual and mechanical leveling methods can be used. Ensure that the top elevation of the roadbed meets specification requirements.

11. Subgrade shaping

When the subgrade project is basically completed, check the subgrade center line, elevation, width, slope gradient and drainage structure according to the design requirements. After all are completed, the subgrade construction will be carried out. Plastic surgery. The roadbed renovation adopts mechanical and manual methods. The slope is reshaped and cut from top to bottom according to the designed slope. No soil shall be used to subsidize the slope. After the subgrade project is completed, a completion measurement must be carried out as a basis for completion acceptance.

5. Other requirements

1. All construction personnel should strengthen their sense of responsibility and strictly establish quality awareness. All construction team leaders, technical leaders, technicians and foremen must As the quality responsible person and guarantor, we have unshirkable responsibilities.

2. At the same time, we must pay attention to safe production, strengthen safety education, establish and improve safety rules and regulations, set up safety banners and warning signs on site, and set up safety officers to supervise and manage on-site to eliminate all unsafe factors and ensure construction No safety incidents occurred during the period.

Please do your job seriously, seize the opportunity early, and strive to complete the construction and production tasks as soon as possible. Sincerely, thank you! !