scholarly journals Development and Application of Precast Concrete Double Wall System to Improve Productivity of Retaining Wall Construction

2020 ◽  
Vol 12 (8) ◽  
pp. 3454
Author(s):  
Seungho Kim ◽  
Dong-Eun Lee ◽  
Yonggu Kim ◽  
Sangyong Kim

The construction of most apartment underground parking lots utilizes reinforced concrete (RC) structures composed mainly of rebar work and formwork. RC structures lower construction efficiency and significantly delay the construction because they require a large number of temporary materials and wooden formwork. In this study, a precast concrete double wall (PCDW) system was developed to address the existing problems of RC structures and to improve the productivity of retaining wall construction. PCDW is a precast concrete (PC) wall in which two thin concrete panels are connected parallel to each other with truss-shaped reinforcement between them. PCDW can contribute to securing integrity, reducing the delay in construction, and improving quality. An overall process for the member design and construction stage of the PCDW system was proposed, and its improvement effects were examined regarding various aspects in comparison to the RC method.

PLoS ONE ◽  
2021 ◽  
Vol 16 (2) ◽  
pp. e0246407
Author(s):  
Fa Che ◽  
Chao Yin ◽  
Xingkui Zhao ◽  
Zhinan Hu ◽  
Lu Sheng ◽  
...  

Although embankment seismic damages are very complex, there has been little seismic fragility research yet. Researches on seismic fragility of bridges, dams and reinforced concrete (RC) structures have achieved fruitful results, which can provide references for embankment seismic fragility assessment. Meanwhile, the influencing degrees of retaining structures, such as retaining walls on the embankment seismic performances are still unclear. The K1025+470 embankment of the Xi’an-Baoji expressway was selected as the research object, and the finite difference models of the embankment fill-soil foundation system and embankment fill-soil foundation-retaining wall system were established. The ground-motion records for Incremental Dynamic Analysis (IDA) were selected and the dynamic response analysis were conducted. Probabilistic Seismic Demand Analysis (PSDA) was used to deal with the IDA results and the seismic fragility curves were generated. Based on the assessment results, the influences of the retaining wall on the embankment seismic fragility were further verified. The research results show that regardless of which seismic damage parameter is considered or the presence or absence of the retaining wall, larger PGAs always correspond to higher probabilities of each seismic damage grade. Seismic damages to the embankment fill-soil foundation-retaining wall system are always lower than those of the embankment fill-soil foundation system under the same PGA actions, thus, the retaining wall can decrease the embankment seismic fragility significantly.


2011 ◽  
Vol 9 (2) ◽  
pp. 241-259 ◽  
Author(s):  
Radomir Folic ◽  
Damir Zenunovic ◽  
Nesib Residbegovic

The available experimental and numerical results of many studies of behavior of reinforced concrete connections for different stages of loading, up to fracture loading, are presented and analyzed in this paper. The problem of beam-column connection (or plate-wall connection) in prefabricated monolithic structures is emphasized. Fracture mechanisms of RC structures, the theoretical basis for their analysis, and the use of fracture mechanics in RC structures were also considered, as well as the mathematical models of prefabricated connections. In order to formulate an adequate mathematical model for calculating the connections, the dominant parameters influencing the behaviour of these connections were analyzed. A failure model for the prefabricated wall - monolithic RC plate connection was formulated. In building the model, the results of implemented experimental and numerical research of prefabricated connection in the MMS system from 2007 were used. Experiences with the implementation of the aforementioned construction system in structures in Tuzla, in the 1980's last century, were additionally used. The proposed mathematical models provide a sufficiently accurate failure assessment of prefabricated reinforced concrete connections.


2017 ◽  
Vol 1 (1) ◽  
pp. 138-167 ◽  
Author(s):  
Lucas Rosse Caldas ◽  
Júlia Santiago de Matos Monteiro Lira ◽  
Rosa Maria Sposto

O setor da construção civil é apontado como um grande consumidor de recursos naturais e causador de diversos impactos ambientais. Neste sentido, verificam-se, nos últimos anos, iniciativas do setor para melhoria da qualidade e aumento da eficiência de seus processos, entre eles o desenvolvimento de sistemas construtivos mais racionalizados e industrializados, podendo ser citados a alvenaria estrutural e painéis pré-moldados de concreto armado. No entanto, o setor ainda carece de formas de avaliar os reais impactos ambientais desses diferentes sistemas, ao longo de seus ciclos de vida. Assim, o presente estudo buscou aplicar a metodologia de Avaliação do Ciclo de Vida (ACV) para a comparação de impactos ambientais de dois projetos de habitação de interesse social (HIS), sendo um de alvenaria estrutural de blocos cerâmicos e outro de painéis pré-moldados de concreto armado, considerando o impacto dos diferentes desempenhos térmicos desses sistemas em seis zonas bioclimáticas brasileiras. O estudo apresentado é do tipo “berço ao portão com opções”, em que os estágios de produção, substituição dos materiais e uso de energia da habitação foram considerados. Foram utilizados dados secundários, modelagem ambiental no software SimaPro e simulação termoenergética no software DesignBuilder. A habitação de painéis pré-moldados de concreto apresentou maiores impactos ambientais nas seis zonas bioclimáticas estudadas, sendo que a cidade de Teresina foi a maior e Curitiba a menor. O estágio de uso se mostrou o mais significativo para todas categorias de impacto ambiental avaliadas. Conclui-se a importância de se avaliar o desempenho térmico em diferentes zonas bioclimáticas para estudos de ACV aplicados às edificações brasileiras.Resumen El sector de la construcción es señalado como um grande consumidor de recursos naturales por consiguiente de diversos impacto ambientales. En este sentido, se observan en los últimos años iniciativas para beneficio de la calidad y la eficiencia en sus procesos, como por ejemplo el desarrollo de sistemas constructivos más racionalizados e industrializados, pudieran citarse la albañilería estructural y paneles pre-fabricados de hormigón armado. Sin embargo, este sector aún carece de caminos para evaluar los reales impactos ambientales de los diferentes sistemas a lo largo de su ciclo de vida. En este contexto, el presente estudio busco aplicar la metodología de Análisis de Ciclo de Vida (ACV) para comparar los impactos ambientales de dos proyectos de viviendas de interés social (HIS), siendo en este caso uno de ellos de albañilería estructural utilizando bloques cerámicos y el otro, con utilización de paneles pre-fabricados de hormigón armado. El presente estudio es un “cuna a la puerta con opciones” en donde cada etapa que comprendía producción, substitución y el uso de energía en la vivienda fue considerada. Fueron utilizados para procesar los datos, para el modelo ambiental el software SimaPro y para la simulación termo energética DesignBuilder. La vivienda de paneles pre-fabricados de hormigón presentó mayor impacto ambiental en las seis zonas bioclimáticas estudiadas, donde en el caso de la ciudad de Teresina se presento el mayor impacto y en Curitiba el menor. La etapa de uso se mostró lo más significativo para todas las categorías de impacto ambiental evaluadas. Se concluye que evaluar el desempeño térmico en diferentes zonas bioclimáticas es de grande importancia para estudios de ACV aplicados en las viviendas brasileiras. Abstract The construction industry is a large consumer of natural resources and is responsible for several environmental impacts. In this sense, it is verified, in recent years, initiatives of the sector to improve the quality and increase the efficiency of its processes, among them the development of more rationalized and industrialized construction systems, such as structural masonry and precast reinforced concrete panels. However, the sector still lacks ways to assess the real environmental impacts of these different systems, throughout their life cycles. Thus, the present study aimed to apply the Life Cycle Assessment (LCA) methodology for the comparison of environmental impacts of two social housing projects (HIS), one of ceramic brick structural masonry and another one of precast reinforced concrete panels, considering the impact of the different thermal performances of these systems in six Brazilian bioclimatic zones. The study presented is “cradle-to-gate with options” type, including the stages of production and replacement of materials and energy use of the house were considered. Secondary data were used, environmental modeling in SimaPro software and thermal-energetic simulation in DesignBuilder software were done. The precast concrete panel’s house presented larger environmental impacts in the six bioclimatic zones, since the city of Teresina was the largest and Curitiba the smallest. The use stage was the most significant for all environmental impact categories assessed. We conclude the importance of evaluating the thermal performance in different bioclimatic zones for LCA studies applied to Brazilian buildings.


PCI Journal ◽  
1994 ◽  
Vol 39 (1) ◽  
pp. 20-36 ◽  
Author(s):  
Sidney Freedman

PCI Journal ◽  
2012 ◽  
Vol 57 (3) ◽  
pp. 33-46 ◽  
Author(s):  
Nemkumar Banthia ◽  
Vivek Bindiganavile ◽  
John Jones ◽  
Jeff Novak

PCI Journal ◽  
2000 ◽  
Vol 45 (5) ◽  
pp. 20-29
Author(s):  
Gar Muse ◽  
Anthony Di Giacomo

Sign in / Sign up

Export Citation Format

Share Document