Multi-section type variable cross-section dynamic compaction method

Abstract

The invention discloses a multi-section type variable cross-section dynamic compaction method, which is the method for treatment of a building foundation, clearing and leveling are firstly performed on a soft foundation space, and multi-section type variable cross-section dynamic compaction construction is further performed on dynamic compaction tamping points which are arranged according to the construction process flow and the technical specifications. During the process of forming a tamping pit and forming tamping bodies, more than two rams in cross sections which are increased gradually are adopted for ramming a soil body of a soft foundation from bottom to top respectively for forming the tamping pit or an expanded hole, dry soil or aggregate is further backfilled into the tamping pit and rammed, tamping of the tamping pit and the backfilled materials is completed section by section, then more than two sections of the dynamic compaction tamping bodies or replacement pier bodies in the cross sections which are gradually increased are formed from the bottom to the top and full compaction operation in a dynamic compaction region is finally performed. After the method is adopted for dynamic compaction and reinforcement, the overall compactness, the strength of the foundation and the bearing capacity are greatly improved, and the foundation is uniform at the upper part and the lower part. The stress stability, the uniformity and the overall rigidity of the foundation soil are significantly increased. The construction quality is more stable, the compression modulus of the foundation is high, and the settlement value and the settlement difference value are obviously reduced.

Description

technical field [0001] The invention relates to a construction method of building foundation treatment technology, which is mainly aimed at the multi-stage variable cross-section dynamic ramming method construction of weak foundation dynamic ramming reinforcement. Background technique [0002] Among the building foundation treatment technologies, the dynamic compaction method has been rapidly popularized and applied throughout the country due to its advantages such as significant reinforcement effect, wide range of soil types, simple equipment, short construction period, material saving, and low construction cost. However, in deep fill areas, weak foundations with high moisture content or foundation reinforcement with high formation water level, after dynamic compaction treatment, the thickness of the bearing layer of the foundation soil is thin, the soil structure of the lower part of the weak foundation soil is still loose, and the strength and bearing capacity of the found...

AI Technical Summary

Problems solved by technology

After the local foundation soil is stressed, it is easy to have a large amount of subsidence or uneven subsidence between the ramming point and the soil between the ramming points, which will cause the superstructure (structure) to affect the structural safety of the building due to large or uneven subsidence.

Moreover, factors such as the lifting performance of the dynamic ramming machine used in the existing dynamic ramming method and the absorption of the ramming hammer by the rammed pit soil limit the infinite increase of the single-click ramming energy to a certain extent, resulting in weak foundation soil layers. The reinforcement effect in the middle and lower part is poor, and the effective reinforcement thickness is shallow, resulting in a thicker and weak underlying layer in the basement

Images