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Within the Master's course "Civil Engineering" at TU Darmstadt, a project has to be carried out. In the winter term 2018/2019 this was the design and fabrication of a bridge spanning 6 m and made entirely from paper. Students had to find bridge types suitable for the use of paper, develop and optimise cross sections and bracing systems and furthermore prove the load bearing capacity. This included the use of experimental methods explicitly. Finally, the bridge had to be erected crossing a small creek. No materials other than paper, cardboard and glue were allowed. [ABSTRACT FROM AUTHOR]

This paper introduces a novel, cost-effective deployable tool for the construction of highly skewed and curved steel girder bridges that will provide the necessary geometrical adjustments to the adjacent girders for the fit-up and installation of cross-frames. This tool consists of two cables and one hydraulic jack and would be deployed near the location where a cross-frame needs to be installed. The jack would be extended or contracted to rotate the girders such that they are approximately parallel to one another to achieve the desired geometry for the installation of the cross-frame without requiring force-fitting. After the cross-frame is installed, the deployable tool would be released and reused elsewhere. This paper presents a numerical investigation of the efficacy of this deployable tool in facilitating the installation of cross-frames for two prototype bridges: a highly skewed and a curved steel girder prototype bridge. Three-dimensional (3D) finite-element (FE) analyses of the prototype bridges under steel dead load at the construction increment just before the cross-frames would be installed were performed to first understand the challenges in cross-frame fit-up. The deployable tool was then incorporated into the developed FE model to determine the forces in the system throughout its deployment and the installation of the cross-frames. A control sequence for the deployment was developed and evaluated. For the prototype bridges considered in this research, the peak force in the hydraulic jack was 26.6 kN (5.97 k), meaning that off-the-shelf technologies could be used. The peak von Mises stress in the installed cross-frame was 22.4 MPa (3.25 ksi), indicating that the procedure is not overstressing the system. Overall, this research demonstrates the promise of a new tool to facilitate cross-frame installation in highly skewed and curved steel girder bridges and culminates in recommendations on the use of this technology in the field. [ABSTRACT FROM AUTHOR]

Despite wide use of terms such as "digital manufacturing" and "digital fabrication" in the constructional steel industry, actual use to date is mostly limited to research and development activities. In contrast, other heavy industries, such as automotive and aerospace have moved much faster and implemented many aspects of digital manufacturing and fabrication in product creation and traditional workflows. As a foil to the current state of the industry, this paper presents the erection, and disassembly of a simple, two‐storey frame that employs an alternative steel connection that can be manufactured using current plasma, laser, and water jet technologies, referred to as the intermeshed steel connection (ISC). The field demonstration described in this paper shows the connection's ability to reduce on site erection time, substantially reduce the number of site bolts, eliminate site welding, and allow for easy deconstruction. The connection has been under testing and development through a consortium of the University College Dublin, Queens University Belfast and, the University of Minnesota. [ABSTRACT FROM AUTHOR]

This paper discusses the unique replacement of three historical bridge spans across the Hracholusky dam in the Czech Republic. The erection of the bridge was performed using longitudinal launching of a new bridge structure onto the old one, connecting and rotating the structure around a longitudinal axis before removing the old span. [ABSTRACT FROM AUTHOR]

This paper intends to study William Golding's 1964 novel The Spire as a post-empire novel having tell-tale signature of a colonialist mind at work behind the primary motive of erecting a spire. The novel is fraught with post-Freudian understanding of human psychology of building phallic structures which also carries the colonialist motive of domination and self-aggrandisement. The architectural aspect of colonialism is a symbolic one of imposition and authority. One can interpret the event of 9/11 as a symbolic destruction of hegemony and neo-imperialism, as represented through the destruction of Twin Towers by the third world terrorists. Golding's novel The Spire can profitably be read against the backdrop of decolonisation and the post-empire hangover of the colonialist mind. [ABSTRACT FROM AUTHOR]

The exponential growth of e‐commerce in the last decade boosts the need of large logistic centers. Steel rack supported warehouses (SRSWs) are one of the most competitive solutions for such infrastructures. The execution phase of SRSWs is challenging, as the stability of the structure has to be ensured throughout the different erection stages. The wind action is here particular important. The density of structural elements and the incompleteness of the SRSWs structure, is a vulnerable condition under wind loads. The determination of wind forces during execution according to the EN 1991‐1‐4 is very limited when dealing with open frame structures, and in particular, with structural systems such as SRSWs. In order to overcome this lack, the wind action on SRSWs during execution has been subject of a recent concluded RFCS research project "STEELWAR". This paper presents the proposal of a method to determine the wind forces on SRSWs under construction. The method is derived from a series of wind tunnel tests. Subsequently, given the inherent limitation of such experimental program, the extension of the method to a range of practical cases is proposed. Finally, an application to a real case study is used to assess the vulnerability of the SRSWs during the execution. [ABSTRACT FROM AUTHOR]

Structural grouting between load-bearing elements is a critical component of precast concrete erection stability planning. Engineers, construction managers, precast concrete erectors, and grout installers require critical education and training to avoid localized structural failures and, in extreme cases, catastrophic collapses of total structures. Although current building codes and standards provide no specific requirements and limited guidance for installation or special inspection of these grouted joints, steps must be taken by responsible entities to begin to develop and formalize procedures to ascertain the quality and extent of installed grout, especially in nonvisible places. Each project must have a dependable methodology and procedure to ensure that all grouting required by the precast concrete engineer is properly installed, and this procedure must include mechanisms to mark completion for all inspector/ reviewer entities to visibly see (such as buried columns or grouted couplers). The procedure must also require certain individuals (such as the precast concrete erection supervisor, main grouter, or field engineer or manager) to be accountable for following the erection stability plan and its corresponding grouting and welding requirements. Companies responsible for installing structural grout must ensure that their workers are well trained on proper grout mixing, placing restraints, and associated challenges and are retaught whenever significant time passes between projects. Training must also be conducted whenever new members join field crews. As demonstrated throughout this white paper, the industry must consistently produce and adhere to project-specific erection stability plans that incorporate allowable building progress with welded and grouted completion points and issue stop work directives, without exception, if not achieved. Moreover, each project must have a dependable methodology and procedure to ensure that all grouting required by the precast concrete engineer is properly installed. It is imperative that lessons learned from the historical lack of consistent attention to this highly critical building connective element be shared so that the industry can move forward from these past issues while maintaining a permanent mindset of the risk to life safety if grout is not given the utmost attention. [ABSTRACT FROM AUTHOR]

Structural grouting between load-bearing elements is a critical component of precast concrete erection stability planning. Engineers, construction managers, precast concrete erectors, and grout installers require critical education and training to avoid localized structural failures and, in extreme cases, catastrophic collapses of total structures. Although current building codes and standards provide no specific requirements and limited guidance for installation or special inspection of these grouted joints, steps must be taken by responsible entities to begin to develop and formalize procedures to ascertain the quality and extent of installed grout, especially in nonvisible places. Each project must have a dependable methodology and procedure to ensure that all grouting required by the precast concrete engineer is properly installed, and this procedure must include mechanisms to mark completion for all inspector/ reviewer entities to visibly see (such as buried columns or grouted couplers). The procedure must also require certain individuals (such as the precast concrete erection supervisor, main grouter, or field engineer or manager) to be accountable for following the erection stability plan and its corresponding grouting and welding requirements. Companies responsible for installing structural grout must ensure that their workers are well trained on proper grout mixing, placing restraints, and associated challenges and are retaught whenever significant time passes between projects. Training must also be conducted whenever new members join field crews. As demonstrated throughout this white paper, the industry must consistently produce and adhere to project-specific erection stability plans that incorporate allowable building progress with welded and grouted completion points and issue stop work directives, without exception, if not achieved. Moreover, each project must have a dependable methodology and procedure to ensure that all grouting required by the precast concrete engineer is properly installed. It is imperative that lessons learned from the historical lack of consistent attention to this highly critical building connective element be shared so that the industry can move forward from these past issues while maintaining a permanent mindset of the risk to life safety if grout is not given the utmost attention. [ABSTRACT FROM AUTHOR]

Sexual motivation is an abstract concept referring to the mechanisms determining the responsivity to sexually relevant stimuli. This responsivity determines the likelihood of producing a sexual response and the intensity of that response. Both responsivity to stimuli and the likelihood of making a response as well as the intensity of response are characteristics of an individual. Therefore, we need to assume that the concept of sexual motivation materializes in physiological mechanisms within the individual. The aim of the present communication is to analyze the requisites for the endeavor to materialize sexual motivation. The first requisite is to provide an operational definition, making the concept quantifiable. We show that parameters of copulatory behavior are inappropriate. We argue that the intensity of sexual approach behaviors provides the best estimate of sexual motivation in nonhuman animals, whereas the magnitude of genital responses is an exquisite indicator of human sexual motivation. Having assured how to quantify sexual motivation, we can then proceed to the search for physiological or neurobiological underpinnings. In fact, sexual motivation only manifests itself in animals exposed to appropriate amounts of gonadal hormones. In female rats, the estrogen receptor α in the ventrolateral part of the ventromedial nucleus of the hypothalamus is necessary for the expression of sexual approach behaviors. In male rats, androgen receptors within the medial preoptic area are crucial. Thus, in rats sexual motivation can be localized to specific brain structures, and even to specific cells within these structures. In humans, it is not even known if sexual motivation is materialized in the brain or in peripheral structures. Substantial efforts have been made to determine the relationship between the activity of neurotransmitters and the intensity of sexual motivation, particularly in rodents. The results of this effort have been meager. Likewise, efforts of finding drugs to stimulate sexual motivation, particularly in women complaining of low sexual desire, have produced dismal results. In sum, it appears that the abstract concept of sexual motivation can be reliably quantified, and the neurobiological bases can be described in non-human animals. In humans, objective quantification is feasible, but the neurobiological substrate remains enigmatic. [ABSTRACT FROM AUTHOR]

The sexual dysfunction in males is, therefore, the result of the disorder of the normal sexual function continuously and over a certain period of time. The term "dysfunction" comes from the Greek "dis" - a prefix with a negative sense of the term sickness and "function", replacing the name of sexual impotence (Latin impotentia, ae), signifying the impotence of a person to achieve certain things. [ABSTRACT FROM AUTHOR]

Steel structure plays a significant role in civil engineering. However, there are many factors affecting steel erectors and contractors to have a successful erection of steel structures. Thus, this study seeks to examine the factors affecting steel structure erection in construction projects within the context of a developing country. The study adopted a survey research method; a questionnaire to identify 47 factors, were assessed. A purposive sampling approach was used to identify 20 construction companies specialising in steel structures erections in Lagos, Nigeria. Sixty-three (63) questionnaires were distributed to the targeted population, which included 32 project managers, 14 project engineers and 17 site engineers of current and past steel structure projects carried out by the selected companies in Lagos. The data collected were analysed using descriptive and inferential statistics. The results revealed skills and experience, job site planning, availability of electrical power for tools, insufficient supervision and method of construction as the top most five factors affecting steel structure erection in construction project in Nigeria. The findings provide in-depth insight of the factors affecting steel structure erection in construction project that can help project managers in development of strategies for improving the erection of steel structure in the construction industry. [ABSTRACT FROM AUTHOR]