L68B1 Mast Section Common problems and construction technology in tower crane foundation construction
The stability of tower crane foundation is very important. Its huge body is composed of steel structure. In addition to lifting very heavy goods, the tower crane foundation has to bear a very large weight. In the tower crane accident, it is caused by the unqualified tower crane foundation that accounts for a large proportion. So, what should be paid attention to in the construction of tower crane foundation?
Common problems in tower crane foundation construction:
In order to rush to the construction period, some of the construction sites are installed hastily when the concrete strength is not enough, so that the load-bearing of the tower crane exceeds the ground stress limit, which leads to the unfortunate event of collapse and overturning;
In some construction units, the excavation work near the tower crane foundation leads to landslide and even displacement, which leads to tower crane accidents;
In recent years, many cities in China have produced groundwater funnel due to excessive groundwater extraction, which leads to uneven settlement and affects the operation and construction of tower crane.
Tower crane foundation construction technology:
When the construction unit is building the tower crane foundation, it must ensure that the ground endurance meets the design requirements, and the strength of reinforced concrete shall be at least 80% of the design value.
For the tower crane foundation with basement engineering, special treatment measures shall be taken: for example, pile driving under the foundation, and the reinforcement at the pile end shall be firmly welded with the foundation anchor bolt. The bottom of the concrete foundation shall be flat and compacted, and the bottom of the foundation shall not be made into a pot. The foundation anchor bolt size error must be constructed in strict accordance with the requirements of the foundation drawing. The anchor bolt shall be kept enough exposed to the ground, and each anchor bolt shall be pre tightened with double nuts.
Before installation, the foundation surface shall be treated to ensure that the levelness of the foundation cannot exceed 1 / 1000. At the same time, the tower crane foundation shall not accumulate water, which will cause uneven settlement of the tower crane foundation. No pit or trench shall be dug at will near the tower crane foundation.
