Risk-Cost Optimized Maintenance Strategy for Steel Bridge Subjected to Deterioration

This paper aims to develop a deteriorated bridge maintenance strategy that ensures the safe operation of steel structures and minimizes the total risk. Five common failure modes are considered for the deteriorated bridge: flexure, shear, deflection, fatigue failure for girder, and chloride attack for the concrete deck. Time-dependent and system reliability analyses are carried out to find the probability of failure under these failure modes. Risk-cost optimization is then used to determine the maintenance strategy. This method was applied to a working example. It was found that the developed maintenance strategy can predict when, where, and what to maintain for a bridge to ensure its safe and serviceable operation during its lifespan. The proposed methodology can help structural engineers and asset managers repair and maintain bridges under deterioration.

A People’s process: Post-tsunami self-build housing in Tamilnadu (2005-08)

This essay elucidates some of the lessons learnt from the community participatory process adopted by Artes, in the Post- Tsunami housing reconstruction project at Nagapatinam, Tamilnadu (2005-08). The program was a self-build process, respectful of gender. A pragmatic assessment of regional technologies, materials and skills was undertaken. The technological assessment was conducted by the community, in collaboration with structural engineers. Projects under consideration are in Sirkazhi Taluk and Akkaraipettai, Nagapatinam region in Tamilnadu, which had been adversely affected. The projects were nominated as best practices by the UNDP, India (2008) for community participatory processes. It inspired a new sense of belonging and confidence in the community. Besides indigenous construction practices, the community was provided an opportunity to learn new construction skills that they desired, which were beneficial in the longer term. The new construction skill sets ensured the community was independent to build their own dwellings incrementally in later years. The community was no more at the mercy of external contractors. The design of the dwellings also enabled future incremental growth. This research highlights some of the lessons in capacity building of communities; using construction skills to enable them to rebuild their own homes, as well as be self-reliant in future extensions and additions

Seismic Response of Large span slab in Horizontal Setback Building

The demand for multi-storey buildings is increasing day by day. Residential plus commercial building is mainly used for wide span needs. Wide span required for Flat slab, Waffle slab and ribbed slab stands An excellent option for architects when larger openings in a building need to be covered with as few columns as possible. The use of different types of plates is developing as a new trend and is becoming a major challenge for structural engineers. Therefore, it is necessary to study about its structural behavior. The project is carried out under earthquake zone III under the earthquake analysis of G+9 storey building. For this study, four different types of large span slab structure are modelled in C-shape (Horizontal Setback Building) having 10-stories i.e. G+9 storied buildings with 3.50 meters height for each story is modelled and analysed. The plan area of all four buildings is same i.e. 2859 square meters (49.50 m x 82.50 m) each. These buildings were designed in compliance with the Indian Code of Practices for earthquake resistant design of buildings. Base of the building were fixed. The square sections are used for structural elements. The height of the buildings is considered constant throughout the structure. The buildings are modelled using ETABSvr.2016. Keywords: large span slab, ETABSvr.2016, Horizontal Setback Building, Flat slab, Waffle slab and ribbed slab

Slope and Landslide Stabilization: A Review

Slope stabilization is the one of important fundamental aspect for preventing landslides. For a safer design of the structure, slope stabilization is very important. There are various studies conducted on slope stabilization and landslide mitigation. Geotechnical Engineers and Structural Engineers play an important role in analyzing and designing slope stabilization and landslide mitigation and prevention. This study is also helpful for the design of slopes. The study also helps for quick assessment of slopes. This paper also explained stabilization methods and techniques for slope. This study is also helpful in improving the shear strength of the slope of soil. This paper helps to understand basic knowledge on slope stabilization and landslides for every Engineer easily.

Slope and Landslide Stabilization: A Review

Slope stabilization is the one of important fundamental aspect for preventing landslides. For a safer design of the structure, slope stabilization is very important. There are various studies conducted on slope stabilization and landslide mitigation. Geotechnical Engineers and Structural Engineers play an important role in analyzing and designing slope stabilization and landslide mitigation and prevention. This study is also helpful for the design of slopes. The study also helps for quick assessment of slopes. This paper also explained stabilization methods and techniques for slope. This study is also helpful in improving the shear strength of the slope of soil. This paper helps to understand basic knowledge on slope stabilization and landslides for every Engineer easily.

Assessment of moisture and mould of hempcrete and straw panels

At present buildings contribute a third of total greenhouse gas emissions. There is a need for sustainable solutions and natural materials, which offer low-embodied energy and their low impact has a promising potential as construction alternatives. Hempcrete is a lightweight insulation material, which provides natural, airtight, and vapor-permeable insulation. Straw panels are also natural construction materials and they consist of extruded wheat straw and are surrounded with recycled paper on all sides. There are some risks, which can be associated with the use of such materials - infestation, biological degradation, presence of moisture, and structural degradation. The aim of the study is to determine the critical moisture level and mould resistance of hempcrete and straw panels. The results of this study are valuable to both scientists and structural engineers.

Optimization of steel roof trusses using machine learning-assisted differential evolution

A steel truss is a preferred solution in large-span roof structures due to its good attributes such as lightweight, durability. However, designing steel trusses is a challenging task for engineers due to a large number of design variables. Recently, optimization-based design approaches have demonstrated the great potential to effectively support structural engineers in finding the optimal designs of truss structures. This paper aims to use the AdaBoost-DE algorithm for optimizing steel roof trusses. The AdaBoost-DE employed in this study is a hybrid algorithm in which the AdaBoost classification technique is used to enhance the performance of the Differential Evolution algorithm by skipping unnecessary fitness evaluations during the optimization process. An example of a duo-pitch steel roof truss with a span of 24 meters is carried out. The result shows that the AdaBoost-DE achieves the same optimal design as the original DE algorithm, but reduces the computational cost by approximately 36%.

Seismic Response of Large span slab in Horizontal Setback Building: A Review

The demand of multistory Building is increases day by day. The residential plus commercial building predominantly used for the need of large span. The large span is needed for Flat slab, Waffle slabs & ribbed slab stands as an excellent option for architects when larger spans in a building has to be covered with the least possible number of columns. The use of different types slabs are evolving as a new trend and are becoming a big challenge for structural engineers. Therefore it is necessary to study about its structural behavior. The paper is review the behavior of different types slab for large span type of building. Final aim to gets the suitable type of slab for large span for effective manner. It is found that very less work is taken setback building with large span, it is required to analysis on the setback building with large span. Keywords: Flat slab, Waffle slabs, ribbed slab, multistory Building, large span.

RESEARCH ON FORCE AND MODAL ANALYSIS OF THE CANTILEVER ROOF MODEL OF A STADIUM

The large-span roof structure is favored by architects and structural engineers all over the world for its novel architectural shape and reasonable structural characteristics. It has been widely used in large public buildings such as sports buildings, memorial buildings and cultural buildings. Based on the structure design of the fourth national college students’ competition winning entries for the model, this paper introduces the stadium upper cantilever roof structure model selection, process design, interface, etc. Using the finite element software ANSYS to analyze the model structure under different load conditions of the static performance, we acquire its natural frequency. The results show that the model meets both the strength and stiffness requirement.

The influence of transformational leadership, digital technology and work culture diversity on the effectiveness of the construction implementation team

The construction project implementation team generally consists of clients, project managers, financiers, legal consultants, design leaders (architects or structural engineers), other specialized consultants, main contractors, subcontractors, cost consultants and suppliers, who must work together effectively to realize project goals. Leadership, the use of digital technology and cultural diversity characterize the effectiveness of the project implementation team. This study aims to determine the positive effects of transformational leadership, digital technology (digitization), and cultural diversity on the effectiveness of the project implementation team. This research is a survey research, involving 200 company respondents, members of the construction industry professional association in Jakarta. Multiple regression is used to analyse data. The results showed that transformational leadership, digital technology (digitization) and cultural diversity had a significant positive effect on the effectiveness of the project implementation team.