Masonry: Building Pathologies and Design

Cities across world are affected continuously with terrorist attacks. These attacks happens particularly on Embassies, Parliaments, trade centres and others significant buildings. The nature of the blast intensity in case of terrorist attach depends upon the detonator used and its distance from the ground zero. The research here present a design of blast resistant building planned in Mumbai, India. The design showcase a model blast resistant method that can be applied for the design of similar buildings affected by terrorist attacks. Some of the key aspect of this model methods are blast intensity, blast load and retaining wall. Moreover, the chapter, illustrates how does the structural components of building reacts during the blast? How can we plan for safer cities? How the important institutional buildings can be protected in event of terrorist attach? What kind of urban planning is essential for blast resistant cities. Furthermore, a case illustrates the details design for blast resistant buildings.

The facade of blast resistant buildings are important for safety during the event of blast in cities and industrial complexes. The design of these buildings includes design of blast wall and estimation of intensity of blast. Blast wall plays significant role in reducing the blast waves on the building. Generally, this blast wall faces towards the source of blast. Significantly, these are main facades of the building viewable by visitors. So, it is indeed important to design these wall to make aesthetically appealing for visitors. Many of these building are located at important locations in cities and industrial complexes. So, making a landmark design is required for these types of the buildings. The research here illustrate a design of facade for the blast resistant building with use of innovative material made from concrete by use of polyurethane formliner. Moreover, it looks into the questions like how the blast wave affect the exterior of building? How to rehabilitate the old building facade? How concrete can be used as a material for making aesthetic in blast resistant building? Furthermore, it also illustrate the design criteria for the blast resistant buildings with emphasise on the architectural design.

Geometric patterns in interior and exterior of building provides an appealing aesthetic. The chapter here illustrates a project for rehabilitation of the cafeteria in an administrative building. In this project the rehabilitation of old interior was undertaken through use of innovative aesthetic consideration of design. Geometric patterns are parts of design combinations used by many designers in exterior and interiors. The research here investigates how geometric patterns can be applied in the architectural design process? What is the process of rehabilitation in small spaces in buildings? How materials are designed in rehabilitation of interior spaces? What are the architectural considerations for design of interiors? How structural criteria are assessed before rehabilitation of old interiors? Indeed, it is important to combine aesthetic and structural knowledge in rehabilitation. So, the research here illustrates an application of hexagonal patterns in the architectural design process for rehabilitation of old interiors.

In this work a novel seismic outer coating applied to masonry structures are studied in order to investigate obtained benefits both from seismic and energetic points of view. The innovative seismic coat consists of a frame made up of Cold-Formed Steel (CFS) members, within which a thermo-acoustic alveolar insulation is inserted. OSB (Oriented Strand Board) panels are bolted to the frame on the outside. The system is completed with an ultra-thin heat reflective insulation, a ventilated wall and a brick finishing. In this way, the CFS frame acts as system withstanding vertical loads, OSB panels provide the seismic action dissipation and the remaining elements are responsible for energy efficiency. The system is connected by bolts on the perimeter walls of masonry buildings and covers the entire facades starting from the foundations. The aim of this research is to find a solution to combine the increase both in term of seismic safety and energy efficiency with a light, flexible and economical system which can replace the traditional thermal coat thanks to both the higher energy performance and an additional seismic resistance, which is not provided by the traditional envelope systems. Firstly, an experimental test on a masonry wall has been simulated by ABAQUS code and, afterwards, the seismic benefits deriving from using the novel coat have been shown in the implemented FEM model through a parametric analysis. Finally, the coat system has been applied to a case study building hosting the high school “Leccisotti”, in the district of Foggia, Italy, with the aim to evaluate the increase of seismic safety and energy behaviour deriving from its use.

The paper discusses the structural behaviour of concrete struts deteriorated by internal swelling reactions due to delayed ettringite formation (DEF). To assess this behaviour, non-linear finite elements analyses were performed using CDP model of ABAQUS, which was calibrated and validated. The effects of the internal swelling reactions were simulated numerically using a strategy of decreasing mechanical properties of concrete. MATLAB scripts were developed to automate the process of determining the CDP model parameters, especially those related to the damage in tension and compression with few input data. Decreases in the first crack and failure loads of 78 and 56% were observed which means that DEF expansions are an important issue in the load capacity of concrete structures. Besides, it was also observed a significant increase in cracks openings width, even for low expansion level, with values of 3.65 mm, and for high level of expansion with values of 4.51 mm. This is a relevant aspect for the durability of concrete structures that is severely affected by DEF expansions.

In this work, it was analyzed in detail the problem of the extensive cracking in the pile cap foundation originated by the delayed ettringite formation, possibly from a high heat of hydration coming from the concreting of the large volume of concrete. Laboratory tests were performed to evaluate the transport properties of concrete samples, as well as their physical and chemical composition using advanced analyses. The tests performed were apparent porosity, gas permeability, scanning electron microscopy, X-ray diffraction and Raman spectroscopy. The presence of crystalline products of the alkali-aggregate reaction was proven through physical–chemical analyses, such as Raman spectroscopy and EDS. As well as the ettringite crystals found in XRD standards, SEM images and the chemical composition of EDS. The porosity showed a high value (between 9 and 10%), as well as the concrete permeability (10^–16 and 10^–15), determining the negative influence of ISR on the transport properties. Therefore, the methods used have proven to be effective in understanding the problem encountered and have the potential to be used in the design and execution of pile cap blocks.

Early deterioration of foundations of reinforced concrete building has been reported with relative frequency in last years. This this deterioration process is often characterized by an extensive mapping cracking process on concrete surfaces that occurs due to several types of internal swelling reaction. In this paper, a real case study of a tall reinforced concrete building that presented a severe process of deterioration of its deep foundations is discussed. Laboratory tests were performed in drilled concrete cores extracted from a deep pile cap block after 19 years of the begin of the construction. Test to evaluate compressive strength, static and dynamic modulus of elasticity as well gas permeability and scanning electron microscopy using advanced analyses were performed to assess information to find out the main mechanism responsible by the strong deterioration found in field inspections performed. Chemical alterations of material were observed, mainly by DEF, which significantly affected the integrity and durability of the structure. Dynamic modulus of elasticity showed to be a best indicator of damage induced by ISR in the concrete than the it’s compressive strength. Rehabilitation procedures executed using strengthening procedures to provide the complete restoration of the structural integrity of the element deteriorated proved to be a good solution to retrofit pile cap deteriorated by expansions due to ISR in concrete.

Waterproofing membranes are subjected to thermal, physical, chemical, and mechanical actions, which generate interactive stresses in the cover system. These interactions, which affect life expectancy of membranes, depend on the chosen technical solution of the flat roof system, materials used, geographical locations, climate and weather conditions, construction method and usage. Therefore, waterproof membrane is subjected to stresses varying over time and space, which depend on decisions and actions taken during planning, construction, and management phases. As for other engineering fields, the definition of procedures for the analysis of stress phenomena, which occur mainly on the waterproofing element, would be desirable. Of course, this would imply the development of focused experimental test methods based on more sophisticated instruments like DMA. Modelling of aging phenomena and early decay may serve as a tool of knowledge, able to ameliorate materials and direct and optimize the design towards more reliable construction systems, avoiding a blind and exclusive reference to codes of practice.