Mixed-in-Place (MIP) Construction material, class 150-230

The Mixed-in-Place material (MIP material) is formed directly in the ground, in that the existing soil is broken up and displaced using a single or triple auger in the MIP process, with the pore spaces filled with binder suspension (Figure 1). The binder suspension, consisting of cement, water, optionally bentonite and optionally concrete admixtures, is produced on site at the MIP construction site. When producing MIP walls, the individual, still-fresh columns already formed in the ground using the MIP equipment are combined into walls using the pilgrim-step method. The declared product is thus formed in the ground and consists of the binder suspension and the enclosed soil, with the dimensions of the auger(s) determining the dimensions of the structural element. The MIP material produced hardens in the intended shape through hydration of the cement into a solid artificial rock. The declared product is the unreinforced MIP material and does not contain steel supports or other built-in components. For reinforced structural elements, load-bearing built-in components or non-load-bearing built-in components, the corresponding proportion must be accounted for separately. The life cycle assessment of the average MIP material with a cement content of 150 kg/m³ to < 230 kg/m³ was determined on the basis of production data. For the use of the product, DIN 4093 applies to structural elements relevant to building-authority approval, as does the General Type Approval „BAUER Mixed-In-Place (MIP)“ with approval number Z-34.26-200 at the place of use (aBG). For structural elements outside the building-authority-relevant area, the provisions of the DWA code of practice DWA-M 512-1 „Sealing systems in hydraulic engineering, Part 1: Earthworks“ apply (DWA).

First, the binder suspension is produced on site using the base materials (cement, mixing water, bentonite, admixtures) (see 2.5 Base materials). The MIP construction material is produced in the subsoil by breaking up the existing soil with a single or triple auger, rearranging it and filling the pore spaces with the prepared binder suspension (Fig. 1). According to Fig. 1, cement-based binder suspensions are usually introduced into the subsoil. As an alternative to standard cement in accordance with EN 197-1, special cement-based binders can also be used, the composition of which corresponds to a CEM III/B, i.e. a mixture of Portland cement and granulated blast furnace slag. Figure 1: MIP process with triple auger [DWA-M 512-1], left: Drilling and mortaring process; right: Homogenization process To ensure the required quality of the MIP elements or walls, the production process is monitored using the parameters that determine the properties. The building material BAUER MIP® Class III (cement content from 150 kg/m³ to < 230 kg/m³) has the following technical properties: The declared unit is one cubic meter (1 m³) of mixed-in-place building material. If MIP components contain steel beams, lattice girders or other built-in parts, these must be considered separately in the life cycle assessment.

The MIP building material is used in a variety of ways in the subsoil. Typical applications of MIP building materials are: Shoring walls for excavation pit enclosures or terrain jumps Sealing walls for flood protection measures, for groundwater barriers or for dyke or dam upgrades Enclosures of contaminated sites Foundation elements (as pile-like elements).