Teratec Construction Report: Step Plate

Solving problems caused by sinking and cavities! Case study of cavity filling in footings by Teratech.

We would like to introduce a case where the problems of sinking and voids under bridge approach slabs were resolved using the Teratec method. The "Teratec method" is a technique that fills the "voids" under bridge approach slabs caused by ground subsidence or groundwater, allowing for the restoration of road functionality to a healthy state in a short period of time. 【Problems Encountered】 On a national highway in Ibaraki Prefecture, voids had developed under the approach slabs due to the Great East Japan Earthquake. The dimensions of the approach slab were 8m x 8m, with a maximum void thickness of about 10cm. Restoration was necessary for safety reasons. 【Reasons for Choosing Teratec】 - Short construction period, which reduces stress for road users due to traffic congestion. - The lightweight materials help suppress re-sinking. 【Feedback After Construction】 Traffic regulations allowed for alternating one-lane traffic, and the construction was completed in one day during daylight hours. The construction vehicle used was a 4-ton truck (L=5.6m). Compared to conventional methods, this was a small-scale project that was completed quickly. *For more details, please visit the external link page or feel free to contact us. https://teretek.jp/plus/case/bridge Toll-free number: 0120-873-835

basic information

【Construction Details】 ■ The material used for filling cavities is a special polyurethane resin (Teratec). ■ After drilling a hole with a diameter of 17.5mm, an injection pipe is inserted, and Teratec resin is injected. ■ To ensure the cavity is completely filled, injection is performed at intervals of 1.5m. ■ The resin expands immediately, filling the cavity and using the load from the footing slab as a counterforce to compact the loosened ground. ■ Once the ground is compacted to withstand the load from the footing slab, the slab is lifted. ■ During construction, the behavior of the footing slab is measured, and injection is completed when it is confirmed that the road surface in the injection area has lifted by approximately 1mm. *For more details, please refer to the external link page or feel free to contact us. https://teretek.jp/plus/case/bridge Toll-free number: 0120-873-835