42 research outputs found
Investigations of steel elements with intumescent coating connected to space-enclosing elements in fire, Fire tests on intumescent coated steel members
The current status of the research program “Optimized use of intumescent coating systems on steel members” (AiF 17200) is presented.The aim of the project is to quantify the influence of space-enclosing elements on the thermal behaviour of supporting steel members. Those elements cause partially restrained expansion of the fire protection system. Experimental investigations on beams and columns directly connected to space-enclosing elements are presented. Additionally, numerical simulations are performed for temperature field calculations of steel elements with intumescent coating. As a new development, the numerical model takes into account the expansion process of intumescent painting. The setup of the numerical model is introduced
Validation of the Dynamic Amplification Factor in Case of Historic Railway Steel Bridges with Short and Medium Spans
AbstractOne of the significant parameters in design as well as fatigue assessment of railway bridges is the dynamic factor. The dynamic factor, also called dynamic amplification factor (DAF), must be applied to the static load model in order to take account of dynamic magnification of stresses and vibration effects in the bridge. The dynamic factor which actually enhances the static load effects depends on many parameters that are difficult to take into account with reasonable accuracy. The maximum bridge-span, train speed, self-weight, expansion joints if any is placed in bridge, the type of bridge supports and finally soil–structure interaction are among these parameters. This paper studies the variations of the analytical and experimental observations on steel railway bridge dynamics. For this purpose the measured stresses due to passing a locomotive through a historical steel railway bridge in Germany are compared with the calculated stresses contemplating the dynamic factor proposed by EN1991-2 [1] applied to the static load model of the same locomotive
Experimental investigations on the load bearing behaviour of an innovative prestressed composite floor system in fire
[EN] In Germany, regulations for hollow spaces in slab systems require 30 minutes standard fire resistance of the load-bearing steel construction. Within a current national research project a natural fire scenario for the hollow space was developed based on realistic fire loads and ventilation conditions in the hollow space. Assuming this realistic fire scenario in the hollow space, two large scale tests on an innovative composite floor system were performed to evaluate the influence on the load bearing behaviour of the floor system. The integrated and sustainable composite floor system consists of a prestressed concrete slab, an unprotected, bisected hot rolled I-profile with composite dowels either in puzzle or clothoidal shape, and removable floor panels on the top of the I-profile. This floor system ensures the opportunity to adjust the technical building installations in accordance with the use of the building. This integrated and sustainable composite floor system was developed in several research projects. The standard fire resistance R90 for the fire scenario below the slab system has already been proven successfully. In this paper, experimental investigations regarding the heating and load bearing behaviour of the innovative composite floor system under the newly developed natural fire scenario of hollow spaces are presented. In doing so, the special test set-up to realise the fire tests for the fire scenario hollow space will be described in detail. After the fire scenario for the hollow space, the specimen was subjected to the ISO standard fire curve to establish the failure temperature of the unprotected I-profile. In addition to the temperature development and the load bearing behaviour inside the innovative floor during the heating phase, the cooling phase and the influence of a web opening on the load bearing behaviour will be discussed.This IGF project (IGF-Nr. 18894N) of the FOSTA is supported via AiF within the programme for promoting the Industrial Collective Research (IGF) of the German Ministry of Economic Affairs and Energy (BMWi), based on a resolution of the German Parliament.Schaumann, P.; Meyer, P.; Mensinger, M.; Koh, SK. (2018). Experimental investigations on the load bearing behaviour of an innovative prestressed composite floor system in fire. En Proceedings of the 12th International Conference on Advances in Steel-Concrete Composite Structures. ASCCS 2018. Editorial Universitat Politècnica de València. 811-818. https://doi.org/10.4995/ASCCS2018.2018.7020OCS81181
Оценка устойчивости системы аварийного водоснабжения на предприятии ООО «ВОДСНАБ»
Целью данной работы, является: разработка комплекса мер по повышению устойчивости функционирования предприятия ООО "ВОДСНАБ" в случае аварии. В ходе выполнения работы был проанализирован уровень развития систем водоснабжения. Были выявлены проблемы связанные с износом оборудования. Был произведен расчет и разработка схемы насосной станции первого подъема.The purpose of this work is: development of a set of measures to improve the sustainability of the operation of the enterprise LLC "VODSNAB" in the event of an accident. In the course of the work, the level of development of water supply systems was analyzed. Problems related to equipment wear were identified. The calculation and development of the scheme of the first lift pumping station was carried out
Eating disorders in weight-related therapy (EDIT): Protocol for a systematic review with individual participant data meta-analysis of eating disorder risk in behavioural weight management
The Eating Disorders In weight-related Therapy (EDIT) Collaboration brings together data from randomised controlled trials of behavioural weight management interventions to identify individual participant risk factors and intervention strategies that contribute to eating disorder risk. We present a protocol for a systematic review and individual participant data (IPD) meta-analysis which aims to identify participants at risk of developing eating disorders, or related symptoms, during or after weight management interventions conducted in adolescents or adults with overweight or obesity. We systematically searched four databases up to March 2022 and clinical trials registries to May 2022 to identify randomised controlled trials of weight management interventions conducted in adolescents or adults with overweight or obesity that measured eating disorder risk at pre- and post-intervention or follow-up. Authors from eligible trials have been invited to share their deidentified IPD. Two IPD meta-analyses will be conducted. The first IPD meta-analysis aims to examine participant level factors associated with a change in eating disorder scores during and following a weight management intervention. To do this we will examine baseline variables that predict change in eating disorder risk within intervention arms. The second IPD meta-analysis aims to assess whether there are participant level factors that predict whether participation in an intervention is more or less likely than no intervention to lead to a change in eating disorder risk. To do this, we will examine if there are differences in predictors of eating disorder risk between intervention and no-treatment control arms. The primary outcome will be a standardised mean difference in global eating disorder score from baseline to immediately post-intervention and at 6- and 12- months follow-up. Identifying participant level risk factors predicting eating disorder risk will inform screening and monitoring protocols to allow early identification and intervention for those at risk
Eating disorders in weight-related therapy (EDIT): protocol for a systematic review with individual participant data meta-analysis of eating disorder risk in behavioural weight management
The Eating Disorders In weight-related Therapy (EDIT) Collaboration brings together data from randomised controlled trials of behavioural weight management interventions to identify individual participant risk factors and intervention strategies that contribute to eating disorder risk. We present a protocol for a systematic review and individual participant data (IPD) meta-analysis which aims to identify participants at risk of developing eating disorders, or related symptoms, during or after weight management interventions conducted in adolescents or adults with overweight or obesity. We systematically searched four databases up to March 2022 and clinical trials registries to May 2022 to identify randomised controlled trials of weight management interventions conducted in adolescents or adults with overweight or obesity that measured eating disorder risk at pre- and post-intervention or follow-up. Authors from eligible trials have been invited to share their deidentified IPD. Two IPD meta-analyses will be conducted. The first IPD meta-analysis aims to examine participant level factors associated with a change in eating disorder scores during and following a weight management intervention. To do this we will examine baseline variables that predict change in eating disorder risk within intervention arms. The second IPD meta-analysis aims to assess whether there are participant level factors that predict whether participation in an intervention is more or less likely than no intervention to lead to a change in eating disorder risk. To do this, we will examine if there are differences in predictors of eating disorder risk between intervention and no-treatment control arms. The primary outcome will be a standardised mean difference in global eating disorder score from baseline to immediately post-intervention and at 6- and 12- months follow-up. Identifying participant level risk factors predicting eating disorder risk will inform screening and monitoring protocols to allow early identification and intervention for those at risk