As the project for the steel sheet pile for the temporary support of the foundation pit and water, it is not necessary to carry out material inspection and only do the appearance of inspection, in order to meet the requirements of the steel plate pile to correct the work to reduce the piling process difficult.
Appearance inspection includes surface defects, length, width, thickness, end rectangular ratio, flatness and lock shape and so on. Inspection, should pay attention to: ①, into the steel sheet into the impact of the pieces should be cut off; ②, cut holes, cross-section defects should be reinforced; ③, if the steel sheet pile has serious corrosion, should measure the actual section thickness In order to determine whether the calculation needs to be reduced. In principle, all steel piles should be visually inspected and corrected for steel sheets that do not meet the requirements.
Loading and unloading steel sheet pile should adopt two points hanging. When lifting, the number of steel piles per lifting should not be too much, and should pay attention to protect the lock from damage. There are bundled lifting and lifting a single bundle, reinforced bundles, hand command. The order, position, orientation and layout of the sheet pile shall be taken into account in the future construction, and shall be stacked according to the type, specification and length of the construction site respectively. The height of the pile shall not exceed 2M.
Baseline Determination -> Pile Pile -> Steel Pile Punching -> Enclosure, Tie Rod, Hood -> Civil Construction -> Pile Pile
⑴, the baseline to determine: the construction workers in the pit on the gantry set on the axis, leaving the construction needs of the work surface, to determine the location of steel sheet pile construction.
⑵, fixed pile position. In order to indicate the specific pile of steel piles, ash lines marked.
⑶, steel piles hit. Using a separate method, that is, lifting the first steel sheet pile, accurately aligned pile, vibration into the soil, so that the pile through the sand into the impervious to the strong (medium) weathering rock. Hanging the second steel sheet pile, card mouth, vibration into the soil, so repeat the operation, until the foundation pit steel sheet pile curtain completed. When the steel sheet pile is hit, the steel sheet pile is finally closed and closed due to the error of the steel sheet pile, the deviation of the pile and the construction condition, so that the actual length of the curtain can not be guaranteed as an integer multiple of the standard width of the steel sheet pile. The Adjust the approach, generally have to use special-shaped steel sheet pile to close or by adjusting the curtain axis with the standard pile to achieve closure. Due to the accuracy of the steel plate pile wall is not high, so the latter method to achieve the corner of the closure, that is, on both sides of the corner with 10 steel sheet pile to adjust the width of the axis to achieve closure. Such as the emergence of some steel sheet pile length is insufficient, can be used to weld long, generally with fish plate welding method. Take a long time to avoid the adjacent two joints in the same depth, joint position should be staggered more than 1M, and should be placed at intervals.
⑷, Wai purlin, rod, angle support
To strengthen the overall stiffness of the steel sheet pile wall, along the length of the steel piles wall set purlin, purlin with a channel or angle steel, through the rod fixed to the original steel pipe anchor, the rod consists of two Φ25 steel composition, Welded to the steel pipe anchor. For the sake of safety, in the steel sheet pile wall on the five corners on the use of channel or angle to do support. As shown on the right.
⑸, steel sheet pile removal.
After the completion of the civil works of steel sheet pile removal. Due to the larger pit, and the surrounding street parks and B1 ~ B4 building location, can not be too close to the pit operation, it is necessary to use a larger crane and vibration hammer with the removal of steel sheet pile, that is, the use of vibration hammer Forced vibration disturbs the soil, destroys the cohesion of the soil around the steel sheet pile to overcome the resistance of the pull pile and relinquishes the pile by the action of the attached crane.
After the steel sheet pile removed after the pile hole, you must immediately do backfill processing, backfill generally with compaction method or fill method, the material used in the sand.
Monitoring measures for foundation pit
1, the establishment of the benchmark network
In order to predict the stability of the foundation pit and the change of the surrounding environment scientifically, and to forecast and provide accurate and reliable deformation data in time, the deformation and settlement observation network of foundation pit support is established, and the deformation set