1. Basis for compilation
1. Construction drawings of the office building of the department on the east and west sides of the business complex building in Liaoyang City.
2. Technical Code for Building Pile Foundation JGJ94-94
3. Technical Code for Detection of Building Pile Foundation JGJ106-2003
4. "Technical Regulations for the Safety of Construction Machinery" JGJ33-2001
5. Technical Specifications for Temporary Electricity Safety on Construction Site JGJ46-2005
6. "Prestressed Concrete Pipe Piles" 10G409
7. Geotechnical Engineering Survey Report of Liaoyang Commercial Complex Building 1086
8. The construction organization design of the project.
9. Quality, occupational health and safety, and environmental comprehensive management system documents.
Second, the general situation of the project
The foundation of the office building on the east and west sides of the business complex project in Liaoyang City is a compressive pile foundation, and the compressive pile is made of prestressed concrete pipe pile, the pile number is PHC 500 AB 125-8A, the bearing layer at the end of the pile is 2 pebble layers, the pile depth is -2m, and the total number of designed compressive piles is 210, including 6 compressive static load test piles, and the test pile is 9m longBefore the construction of the pile foundation of this project, 3 piles were tested, and the pile length was 12m.
3. Construction preparation
1. Technical preparation.
Familiar with pile foundation construction drawings and safety and technical disclosure.
Determine the pile position and elevation according to the pile plan, and go through the line inspection procedures.
Prepare pile foundation engineering pile sinking records and concealed engineering acceptance records**, and arrange special personnel to record.
2. Preparation of materials.
The prestressed concrete pipe pile of this project purchases the finished pile directly from the manufacturer, and the appearance quality of the pipe pile is checked before entering the site, and the unqualified pipe pile shall not enter the construction site.
Main Material Plan Table 3-1
3. Preparation of machinery and tools.
Construction Machinery and Equipment Table 3-2
4. Personnel preparation.
Workforce Planning Table 3-3
5. Operating conditions.
The construction site has been three links and one level.
The temporary installation of the site has been completed.
Materials have been brought in.
The pay-off line has determined that the pile position has the conditions for mechanical piling.
Fourth, construction deployment
1. Division of construction operation area.
The pile foundation construction of this project is divided into 2 construction operation areas (i.e., the east and west side of the department office building), each operation area is divided into 2 operation construction sections, each construction section is constructed with piles as the key line, and the pile driver pile sinking walking route is shown in the attached drawing.
2. Construction schedule.
July 1, 2011 - July 10, 2011.
Fifth, the construction method
1. Process flow.
Measurement and positioning, pile driver in place, lifting prefabricated pile, stabilizing pile, hammering and sinking pile, sending pile, driving to the bearing layer, collecting hammer, moving pile machine to the next pile position.
2. Construction methods.
The pile foundation construction of this project adopts the dynamic pile sinking construction method (hammering method).
Construction survey pay-off.
Check and review the control pile points to check whether the baseline size of the building is visible and easy to measure.
According to the pile position layout plan, the pile position is measured with a total station, and each pile position is set up with a steel bar standard pile, and the standard pile is clearly marked with paint, and the circle with a diameter of 500 is drawn with white ash with the center of the steel bar standard pile, so as to facilitate the centering of the pile and keep the pile position correct;And measure the actual elevation of each pile position, and set up 2 leveling points outside the site for inspection at any time.
After the pile position is placed, it shall be reported to the supervision and inspection line in time, and the construction shall be carried out after the review is correct.
Lifting, alignment, pile sinking, and pile delivery of prefabricated piles.
Lifting prefabricated piles: first tie the wire rope and rigging used for hanging piles, and then tie the pile body with rigging, and the lifting point is 2 from the upper end of the pile48m, and then start the machine to lift the prefabricated pile, so that the pile tip is vertically aligned with the center of the pile, and slowly put it down and insert it into the soil, and the position should be accurate;Then buckle the pile cap on the top of the pile to remove the rigging.
Stabilize the pile: After the pile tip is inserted into the pile position, first use a small drop distance cold hammer 1 2 times, and the pile enters the soil at a certain depth, so that the pile body, pile frame, and pile hammer are vertically consistent. The vertical inspection of the pile body must be corrected with a line drop or theodolite in both directions, and no visual inspection is allowed, and the theodolite is 15m away from the piling frame. The verticality deviation when the pile is inserted shall not exceed 05%。Before the pile is driven, a ruler is set on the side of the pile or on the pile frame to observe the depth of the pile and record the number of hammer strokes per meter.
Pile sinking: This project uses diesel hammer piling, hammer weight 6t, heavy hammer low blow when piling, pay attention to the pile hammer, pile cap, pile body center line when hammering and sinking pile, to prevent the pile from being eccentric hammering, so as to avoid the pile bending and torsion.
Pile delivery: The elevation of the top of the pile designed for this project is -19m, the average elevation of the ground on site is 276. Need to send piles 155m。When sending piles, the centerline of the piles should be consistent with the pile body, and then the piles can be sent. If the top of the pile is uneven, it can be flattened with thick paper or smoothed with epoxy mortar.
Hammer retraction standard. The piling and hammering of this project adopts the dual control of pile end design elevation and penetration. Each pile is driven to the penetration requirements, and the pile tip elevation enters the bearing layer, and when it is close to the design elevation, or when it is driven to 1m away from the design elevation, it will be accepted in conjunction with the supervisor. After meeting the design requirements, fill in the construction record.
When the pile end reaches the bearing layer 2 pebble layer, the penetration control is the main thing, and the elevation of the pile end is used as a reference.
When the penetration degree has been reached, the design elevation of the pile end has not been reached, the hammering should continue to hit 3 arrays, and the penetration degree of 10 strokes per array is not greater than the value specified in the design to be confirmed.
If it is found that the pile position is quite different from the design requirements, it should be studied and dealt with in conjunction with the design, construction and supervision units. Then the pile shifter moves to the new pile position.
Sixth, quality requirements
1. Stacking and acceptance of prefabricated pipe piles
The prefabricated pipe pile is delivered to the construction site, and the prefabricated pipe pile exit certificate is provided in batches. Attach relevant product quality certificates, test reports, test reports and other materials.
The pipe piles are stacked separately according to specifications, arranged within the lifting working radius near the pile driver, and taking into account the piling direction to avoid steering. The number of stacking layers should not exceed 2, and the wooden wedges to prevent rolling should be pressed on both sides.
When the prestressed pipe pile enters the site, the project quality inspector will jointly inspect and accept it with the on-site supervisor, and fill in the acceptance record before it is allowed to use. If it is found to be unqualified, mark it with a red pen and return it to the manufacturer in time and shall not be used.
2. Quality inspection standards for prestressed pipe piles.
Quality standards for pre-tensioned prestressed pipe piles Table 6-1
7. Pile foundation detection
1. The pile test adopts two methods: static load test and dynamic test.
There were 6 static load test piles, and the static load test was carried out 28 days after the pile was sunk, and the test pile was tested by the slow maintenance stacking method, and the limit value of the vertical compressive bearing capacity of the test pile was 2200kN.
There are 70 dynamic test piles, which are low-strain test methods.
2. The pile foundation testing unit of this project is the Liaoyang Construction Engineering Quality Inspection Center.
8. Safety technical measures
1. Check the underground pipelines within the construction scope before piling to ensure the safety of construction.
2. When piling machinery enters the site, pay attention to prevent collision with electric poles to avoid accidents.
3. The walking route of the pile driver must be smooth and solid to ensure the safety of the collision machine.
4. Comprehensively inspect the machinery before construction, solve problems in a timely manner, and carry out trial operation after inspection, and it is strictly forbidden to work with illness. The mechanical operation must comply with the safety technical operation requirements, be operated by a special person, and strengthen the maintenance of the machinery to ensure the normal use of various equipment and components and parts of the machinery.
5. When hoisting in place, the lifting should be slow, and the rope should be pulled to prevent the pile head from impacting the pile frame and damaging the pile bodyStrengthen inspections, find unsafe situations, and deal with them in a timely manner.
6. When the floor is uplifted or subsided during the piling process, the frame and rail should be leveled or leveled at any time.
7. The mechanical driver should concentrate on the operation, obey the command signal, not leave the post casually, and often pay attention to the operation of the machinery, and correct the abnormal situation in time to prevent the mechanical tilting, dumping, and sudden falling of the pile hammer when it does not work.
8. When driving piles, it is strictly forbidden to correct the pile head bedding by hand, and do not start the hammer or brake too early before the pile hammer reaches the top of the pile, so as not to damage the pile driver equipment.
9. The installation and removal of all power supplies and circuits on the construction site must be operated by a licensed electricianElectrical appliances must be strictly grounded, zeroed, and use leakage protectors.
9. Drawings
1. Piling sequence diagram of the office building of the department on the east side.
2. Piling sequence diagram of the office building of the department on the west side.