HomeVacuum Dynamic Compaction Preloading
Release time：Jul 24,2023
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In coastal areas, hydraulic fill engineering has the characteristics of complex geology, high water content, shallow groundwater burial, and low surface bearing capacity, which are difficult to meet the requirements of building foundation bearing capacity. The foundation pretreatment engineering adopts the reinforcement method of vacuum preloading combined with low-energy dynamic compaction, combining dynamic compaction technology with vacuum preloading to fully utilize the technical advantages of both. The treated foundation bearing capacity is not less than 120kPa, meeting the design requirements, Good reinforcement effect has been achieved.
Low energy level full compaction construction technology
Site organization and leveling - low energy level full compaction construction - site leveling - handover surface vibration compaction - post compaction inspection - evaluation and acceptance.
Low energy level full compaction construction requirements:
1) Site cleaning and leveling. After the removal of the vacuum preloading equipment, the uneven and large height differences within the site should be leveled again to ensure full compaction operation.
2) Full compaction. After the construction of the compaction point is completed, perform two rounds of full compaction, with a single click energy of 800kN · m, two blows per point, and 1/4 hammer marks overlapping.
3) Vibration compaction. After the full compaction is completed and the site is leveled again, vibration compaction shall be carried out using a 15t vibration roller. The wheel marks of each compaction shall overlap by 1/2, and there shall be no obvious wheel marks in the last vibration compaction. Horizontal rolling 3 times, vertical rolling 3 times, a total of 6 times, the water content requirement of rolling is to meet the optimal water content requirement.
The vacuum preloading construction takes 90 days, and after the subsequent low-energy dynamic compaction treatment, the characteristic value of the foundation bearing capacity reaches 126kPa ≥ 120kPa, meeting the design requirements. To make certain contributions to the foundation treatment of flow plastic silt foundation soil with shallow groundwater burial, abundant groundwater, and extremely low foundation bearing capacity in hydraulic fill areas.
