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Lemke S.,Sika Services AG | Moran P.S.,Wisko America Inc.
Proceedings - Rapid Excavation and Tunneling Conference | Year: 2015

For some time now, spray-applied waterproofing has been reviewed and discussed as viable materials and methods for tunnel waterproofing applications. Unquestionably these products have been applied on some underground projects, but seemingly with rather inconsistent results. The aim of this paper is to present an objective overview and to identify some potentially critical limitations of this technology and approach. Source

Tolls J.,Henkel AG | Gomez D.,FEICA Aisbl | Funk T.,Sika Services AG | Seger E.,HB Fuller Deutschland GmbH | Wind T.,Henkel AG
Integrated Environmental Assessment and Management | Year: 2016

Regulation (EC) No 1907/2006 concerning the Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH) requires that environmental exposure assessments be performed for all uses of dangerous substances that are marketed in the European Union in quantities above 10 tons per year. The quantification of emissions to the environment is a key step in this process. This publication describes the derivation of release factors and gives guidance for estimating use rates for quantifying the emissions from the manufacturing and application of adhesives and sealants. Release factors available for coatings and paints are read across to adhesives or sealants based on similarities between these 2 product groups with regard to chemical composition and to processing during manufacturing and application. The granular emission scenarios in these documents are mapped to the broad emission scenarios for adhesives or sealants. According to the mapping, the worst-case release factors for coatings or paints are identified and assigned to the adhesives or sealants scenarios. The resulting 10 specific environmental release categories (SPERCs) for adhesives and sealants are defined by differentiating between solvent and nonsolvent ingredients and between water-borne and solvent-borne or solvent-free products. These cover the vast majority of the production processes and uses and are more realistic than the 5 relevant emission estimation defaults provided in the REACH guidance. They are accompanied with adhesive or sealant consumption rates in the EU and with guidance for estimating conservative substance use rates at a generic level. The approach of combining conservative SPERC release factors with conservative estimates of substance rates is likely to yield emission estimates that tend to overpredict actual releases. Because this qualifies the approach for use in lower-tier environmental exposure assessment, the Association of the European Adhesive & Sealant Industry (FEICA) SPERCs are available in several exposure assessment tools that are used under REACH. Given the limited regional variation in the manufacturing and use processes of adhesives and sealants, the SPERCs may be applicable for emission estimation not only in the EU but also in other regions. © 2015 SETAC. Source

Lemke S.,Sika Services AG | Gerstewitz T.,MAX BOGL Bauunternehmung GmbH and Co. KG
Proceedings - Rapid Excavation and Tunneling Conference | Year: 2015

Forming watertight terminations for connecting tunnel cross passages or other shafts onto the precast tunnel lining segments, represents a technical challenge. Their design and installation in situations with complex component geometry and high hydrostatic pressures is particularly difficult. Until now, only mechanical termination systems using bolts and plates have predominantly been used for this purpose. Due to the clear and well known difficulties and disadvantages of clamped systems, a bonded connection was developed and installed in the Finnetunnel section of the German High Speed Unity Railway System, VDE Project 8.2 "New rail line from Erfurt to Halle/Leipzig." This was used to create watertight connections between the cross passages and the main tunnel lining segments. Instead of clamping the waterproofing membrane on the outside of the segment, a plastic strip/tape was bonded directly to the surface of the concrete using epoxy resin mortar. Once the mortar had cured, the cross passage waterproofing membrane was welded onto the strip. This new form of watertight termination was developed step by step, with expensive, very detailed and large-scale testing carried out before the final installation. In the experimental design, resistance to a hydrostatic water pressure of 9 bar over a time period of approx. six weeks could be sustained. After that, the pressure was raised to 12 bar within eight hours and then maintained at this level for two weeks. Additionally, in a destruction test, the water pressure was even raised up to 55 bar before the test assembly/equipment failed. This paper describes the design principles and successful installation of these new, cost effective and efficacious bonded connections in the Finnetunnel. Source

Tomazevic M.,Slovenian National Building And Civil Engineering Institute | Gams M.,Slovenian National Building And Civil Engineering Institute | Berset T.,Sika Services AG
Bulletin of Earthquake Engineering | Year: 2015

The efficiency of strengthening traditionally built three-leaf stone masonry walls with different types of composite reinforced coating has been investigated. Glass fibre grid in single component fibre reinforced mortar and glass fibre fabric in epoxy resin matrix were used as coating materials. Four different coating types have been applied, with coating placed on one or both sides of the walls, anchored or not anchored to the masonry at the corners of the walls. Ten walls have been tested by subjecting them to cyclic shear loading at constant precompression, among them two walls in the original state as the control specimens. Four walls have been first tested up to the occurrence of the first significant damage, strengthened and then re-tested up to collapse, whereas four walls have been strengthened undamaged and tested up to collapse. All walls failed in shear. Significant increase in lateral resistance with regard to control walls was observed in all cases, up to 2.5–4.0-times the resistance of the control walls. The degree of improvement did not depend on the type of coating but on the technology of application. Although the coating increased the rigidity of the walls, displacement and energy dissipation capacities have been also improved. © 2014, Springer Science+Business Media Dordrecht. Source

Birkhofer B.,Sika Services AG | Debacker A.,Sika Technology AG | Russo S.,Sika Technology AG | Ricci S.,University of Florence | Lootens D.,Sika Technology AG
Applied Rheology | Year: 2012

Ultrasonic Velocity Profiling with Pressure Drop (UVP+PD) is a technique, which allows the measurement of the shear rate dependent viscosity non-invasively in a laminar pipe flow. To assess the performance of different data processing approaches for the extraction of the rheometric values, model fluids are characterized under well defined flow conditions created with a piston setup. Considering the shear rate range available in the pipe flow, a good quantitative agreement is found between the in-line measurements and the off-line measurements made with a rotational rheometer. © Appl. Rheol. Source

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