Türme unter Glocken‐ und Erdbebenlast nach alter und neuer DIN 4178 und 4149

Towers under Bell and Earthquake Loads according to the old and new DIN 4178 and 4149 Due to their slenderness and their function bell towers are especially exposed to dynamic loads. These loads are the dynamic loads due to the ringing of the bells (DIN 4178 of 1978) and earthquake loads (DIN 4149 of 1981). The two for these load cases relevant codes have been updated to the current technical state of knowledge and have been published in April 2005. In this article the differences between the old and new versions of the codes are explained by two selected examples. The consequences of rehabilitation measures of the bells are also considered. It was found that the new versions of the codes lead to higher loads of the towers. To design new towers and to investigate existing ones it is therefore required to use the updated versions of the codes to obtain reliable results.     

Fügen und Verbinden mit UV‐ und lichthärtenden Acrylaten

Joining and connecting with the help of uv‐ and lighthardening acrylates. At the moment in the field of construction adhesively bonded joints are only carried out by the use of silicones. On the other hand alternative adhesives offer many advantages. Beside a higher strength also thinner adhesive bonded joints with completely transparent or coloured joints are possible. To apply adhesively bonded glass the design and calculation of these connections must be ensured. In a current joint research project transparent adhesives of higher strength, will be investigated for their suitability for structural glass. Typical glass constructions, which require transparent, elastic and non‐ageing adhesive bonded joints are subject for investigation.     

Überwachungsmaßnahmen und Bauwerkszuverlässigkeit – Zusammenhänge und Auswirkungen

Monitoring Measures and the Reliability of Structures – Connections and Effects The quality of structures is reflected by its reliability. In case of quality control during the production process lower variations of enclosed parameters like the tolerances of dimensions or material strength will occur. Different variations of these random variables are considered in reliability analysis depending on different intensities of inspection. Hence the intensity of inspection ca be judged with respect to failure probability and resulting safety elements.     

Bauzeit und Baukosten für Stahlbetonarbeiten – Berechnungsmethoden und Anwendung

Construction Time and Cost of Reinforced Concrete Works – Calculation Methods and Application Construction time is of crucial importance when it comes to utilizing the production factors in an effective and efficient way. Construction periods that are too short usually result in higher cost, poorer quality and a larger number of disputes. This paper sets out to demonstrate the calculation of construction time whilst considering key construction management parameters. Beyond a simple, deterministic method, other options for calculation are shown that rely on probability calculus. The approaches described to determine construction time and cost are illustrated by a building project example. The deterministic method results in one value per each calculation process (calculation mode 1). In calculation mode 2, probability calculus is applied in a simple fashion. Both range and probability of occurrence can be considered for the relevant input variables. For the third calculation mode, the Monte‐Carlo method is applied using the @RISK software. For each of the parameters to be determined, this method shows a probability distribution.     

Stabwerke und Teilflächenbelastung nach DIN 1045‐1 und Eurocode 2 – Modelle und Anwendungen

Strut‐and‐Tie Models and Concentrated Loading according to DIN 1045‐1 and Eurocode 2 – Modelling and Application Strut‐and‐tie models are efficient tools for the demonstration of load‐bearing characteristics and for the design of reinforced and prestressed concrete structures. The illustration and determination of so called D‐regions is one of the most common areas of application. Another related problem is concentrated loading. In comparison to bending or shear design, the standards DIN 1045‐1 and Eurocode 2 (DIN EN 1992‐1‐1) provide only limited requirements and information for application of strut‐and‐tie models and concentrated loading problems. In praxis, the Engineer has to find possible solutions on basis of the principles given in the standards. The following paper compares the basic information of DIN 1045‐1 and Eurocodes 2 (DIN EN 1992‐1‐1) concerning strut‐and‐tie‐models and concentrated loading problems and gives additional proposals for certain application issues.     

Einheitliches Fachwerkmodell für Stahlbeton‐ und Spannbetonbauteile unter Querkraft‐ und Torsionsbeanspruchung

Uniform framework model for reinforced and prestressed concrete structural members under shear and torsion loading. Following the design provisions for shear and torsion according to DIN 1045‐1 the following two principle questions are raised: For a lot of situations in standard design praxis the allowable inclination of the concrete strut is determined to an angle as small as about 18° – while such a gentle strut angle in tests could only be proved in case of a high level additional compression force. Additionally, with the given two different design approaches a smooth transition between structures with and without required shear reinforcement is lacking. For the purpose of a general review experimental as well as theoretical investigations for beams under shear loading and torsion loading have been conducted. As consequence of the obtained results a uniform strut‐and‐tie model with simply application has been derived.     

Preisaufschlags- und Preisnachlassverfahren; Kalkulierbarkeit; Eignungsnachweise

Die Erneuerung der übergeordneten Leittechnik in Kraftwerken ist eine Sektorent?tigkeit im Bereich der Elektrizit?t, die von der Anwendung des BVergG ausgenommen ist.     

Trag‐ und Ermüdungsverhalten liegender Kopfbolzendübel unter Quer‐ und Längsschub

Structural and fatigue behaviour of horizontally lying shear studs subjected to vertical and longitudinal shear. In consideration of structural, manufacturing and economic aspects new interesting composite cross sections for buildings and bridges consisting of reinforced concrete and structural steel lead to a horizontally lying arrangement of headed shear studs influenced by edge proximity. Compared to common vertical shear studs the relatively small distance of horizontally lying shear studs from the edge of the slab leads to different bedding conditions of the connectors within the surrounding reinforced concrete material, which results in differing structural and fatigue behaviour of this type of shear connection. For future applications of horizontally lying shear studs on the basis of experimental and theoretical investigations design rules for the shear connection subjected to monotonic vertical shear, monotonic vertical and longitudinal shear and cyclic longitudinal shear are presented.     

Lager‐ und Abfüllanlagen in Biogasanlagen – Zulassungen für Bauprodukte und Bauarten

Biogas‐storage‐ and Biogas‐filling‐facilities – Approvals for construction products and techniques In accordance with the building and water regulations, assessments of fitness for use pursuant to the Building Codes can be issued for construction products and techniques used in storage and filling facilities of biogas plants since September 2015. The article explains which building and water regulations apply to construction products and techniques intended for such use. The requirements in both legislative areas have considerable effects on the characteristics of construction products and techniques intended for contact with fermentation substrates and fermentation residues. In particular, the water regulations set out strict requirements for construction products intended for use in such facilities, which are reflected in high verification requirements for functional reliability and fitness for use. The paper focuses on general aspects, which apply to all approval elaboration and granting processes for construction products and techniques used in the before‐mentioned areas of biogas plants. More specific aspects of approval elaboration will also be addressed, using the example of selected construction products and techniques. The article provides guidance for product manufacturers and for qualified planning and design. It also explains certain specific provisions to be met by specialised firms and qualified professionals within the meaning of water legislation and by operators of biogas storage and filling facilities.