The project in Huangshan City, Anhui Province is located in a medium-low mountain terrain area with abundant groundwater resources. The soil type is mainly yellow-brown soil with thick soil layer, high gravel content and good permeability. At present, this place is going to build high-grade villas. To eliminate the hidden danger of building subsidence or damage caused by the change of underground water level, high-strength anti-floating anchor bolts will be used in this project to ensure the building safety and service life.

KTB25-Q830 refined rolled thread bar was initially selected as the anti-floating anchor bolt due to the higher design strength demand. After infield tests, Kelleg’s engineers found that the anchor bar used in original design cannot meet the actual engineering requirements. Finally, after communication with the designer, the construction party decided to choose the KTB32-Q930 refined rolled thread bar.

The project used DTH drill to drill holes with 230mm diameter. At the same time, the lantern centralizer with 180mm diameter is used to ensure single-side grouting thickness of anti-floating anchor bolt, which made better grouting effect. Higher-strength reinforcement and thicker grouting layer made safe and reliable grouting body to resist complex geological environment and ensure the local people’s safety and property.

The construction of anti-floating anchor bolt can be divided into six steps:

First, dig foundation pit on-site in accordance with the design drawing requirements.

Second, initial supporting for foundation pit slope to guarantee its stability and conducive to the follow-up work;

Third, using drilling equipment to drill multiple deep holes in foundation pit;

Next, install anti-floating anchor bolt to the design depth;

Pump machine extraction the groundwater, and filled fully with cement slurry in the hole;

After cement solidification and forming pile foundation, the construction party can carry out the ground construction…

This construction method can not only effectively resist the vertical settlement of buildings caused by the change of underground water level, but also effectively mitigate the destruction or collapse of buildings caused by extreme disasters, such as earthquake, typhoon, etc. At present, refined rolled thread bar has been widely used in more and more construction projects and has been received favorable comments from the construction party.

Kelleg focused on geotechnical anchorage engineering for more than 10 years. We have a professional technical team that can arrive at construction site to provide technical support. Kelleg is committed to providing customers all over the world with systematic geotechnical anchorage engineering solutions through full-process service.