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The simulation of a part's mechanical behaviour has become indispensable in the course of a safe and precise part design. By the means of Finite Element Analysis (FEA) the potential of a material can be utilised optimally and thus parts can be designed under the aspects of a minimised effort in costs and material usage. Beyond that crash simulations of automotive components are constantly gaining a higher importance due to tightened laws regarding the safety of passengers and pedestrians [I]. Therefore in terms of a material- and load-suitable simulation a development of methods which enable a precise prediction of the mechanical behaviour of short-fibre reinforced thermoplastic parts under impact loading is necessary. An adequate approach for this purpose is the integrative crash simulation, which will be described more thoroughly in the following. The required material data determination is discussed as well. Source

Heavy rains occur more frequently over the past years, damaging land and property through backing-up in canalisation and uncontrolled run-off. The landowners claim for damages against the municipalities, whose drains and sewage systems aren't constructed to cope with these so-called .,one-hundred-year" rain events. Their claim for property damage in those cases is principally based on absolute liability according to § 2 Abs. 1 Haftpflichtgesetz (HPflG), quasi-contractual liability according to § 280 Abs. 1 BGB analog or government liability according to § 839 BGB in conjunction with Art. 34 GG. With the help of case studies, the following article displays which aspects are relevant from a legal point of view for the municipal liability for damages caused by backwater. We will give some advice on which steps a municipality should take to protect itself against claims for damages in this regard. The article is split between the issue at hand and the following issue. The first part concentrates inter alia on the landowner's obligation to install a backing-up valve. In general, there is no municipal liability if the landowner omitted to install such a valve. Besides, the municipal duties of care owed to the landowners will be examined, e. g. regarding the dimensioning of the canalisation. A municipality may be subject to a pro rata liability if it breaches a duty of care it owes to the landowner, for example the duty to inform the landowner about modifications of the canalisation which increase the risk of backwater. Source

In the first part of the article (issue 10/2015, gwf-Wasser|Abwasser), we already established that - according to the jurisdiction of the Bundesgerichtshof - a canalisation, which is dimensioned for a calculated rainfall of one year, is not sufficient. As a general rule, damages due to an insufficient canalisation have to be compensated by the municipalities. Apart from that, the first part dealt with the obligation of landowners to install backing-up valves, whose missing excludes the municipal liability wholly or at least partially. The second part concentrates inter alia on exclusions of liability for damages caused by backwater in a municipal ordinance. Such an exclusion of liability is only effective regarding a quasi-contractual basis for a claim, it is not possible to exclude the statutory liability. Besides that, the article deals with the topic of whether and under which circumstances a heavy rain event can be classified as force majeure, which excludes the liability. The jurisdiction is inconsistent in this regard. The last part of the article highlights which factors have to be considered in communal planning of land-use areas to avoid being liable for water damages due to flooding. Taking the topographical characteristics of the surrounding areas into account is of vital importance. As in the previous part of the article, we explain these aspects with the help of case studies and with regard to the relevant statutes. Source

The compatibility of particular components in elastomer recipes determine the distribution and dispersity in the rubber compound, which is responsible for miscibility, processing behaviour in production and last but not least the technical properties of the end-applications. As example of the emulsive system polymer matrix and plasticiser, the three-dimensional Hansen-solubility parameters (HSP) will describe the compatibility. This work explains the practical way, started from contact angle measurements, over the parts of the surface tension to reach over a further empirical calculation model the disperse, polar and hydrogen contents of the solubility parameter. The measured results from a broad spectrum of synthetic plasticiser, means differrent sub-groups, and from HNBR-grades with different concentrations of acrylonitrile are safed over defined volume swelling trials, like swell-tests in solvents with known solubility parameters. Otherwise through swell-tests of all chemical crosslinked HNBR-grades in the broad spectrum of plasticisers, which will confirm the grade of compatibility exactly. In addition, comparisons through literature studies about solubility parameters and a theoretical derivation over the Hoy increment system, for the parts of solubility parameter, completed informations away. The results of elastomer-plasticiser-favourites in compatibility are discussed for typical targets like low-temperature flexibility and heat resistance. Source

The description of the compatibility between synthetic plasticizers and the elasto-meric matrix through the components of the solubility parameter is a relatively old concept, which was developed decades ago. But the easy way of looking at things by using this concept makes it possible for users and innovation leaders to form with limited effort a specific knowledge with scientific depth. This work will show through the correlation between theoretical and practical results, that the solubility parameter concept can thoroughly answer questions of compatibility. Crucially, however, is a multilateral combined approach, as shown in this publication by the example of the swelling of elastomeric materials in media like solvents and plasticisers, by the theoretical derivation of solubility parameter components with the Hoy increment system, and the practical way to find solubility parameter components over determined surface tension components of the emulsive constituent parts: plasticiser and polymer. Source

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