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This article investigates the cause of the failure of some parts of a two-storey building under construction, in Oba-Ile, Akure, Ondo State, Nigeria. The article examines the effect of the quality of sand used for concrete production on the quality of concrete produced from them. The article also investigates whether the provided main and shear rei...
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... as a matter of responsibility, the Federal Government, Ministry of Works and Housing, State and Local Governments, including private individuals and professional bodies should be concerned. Figure 1 shows the collapsed part of the building under investigation, whereas Figures 2 and 3 show the reconstructed combined footing with the column reinforcement of the collapsed part of the building. ...
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Confining reinforcement for concrete columns have been standardized in building standards ACI 318-11 and SNI 03-2847-2013. The observation of building collapse by earthquake normally caused by malfunction of the building columns as bearing elements. The columns were failed because they did not meet the standard of confining reinforcement. In most c...
The use of substandard materials, particularly low quality concrete has been identified in literature as the leading cause of building collapse in Nigeria. The roadside artisans/bricklayers usually produce concrete for building construction without taking the aggregate source into consideration. This paper presents a comprehensive data on the compr...
Most of the seismic damage of existing traditional buildings is due to the absence of practical beam and column structures as the main reinforcement of the building. While a masonry wall as a structural component is commonly negligible due to their relatively low strength in contributing to the frame structure. As a result, when the earthquake stru...
3D steel wire sandwich panels can form an effective alternative construction system. Application and demand for light weight construction in diverse structural elements using 3D panels are enlisted. Non-linear variation of normal strain unveiling the fact that "Plane section remains plane after bending" assumption is not valid for reinforced concre...
Citations
... Например, повышенное содержание ила/глины в песке для бетона привело к снижению качества бетона и, возможно, стало одной из причин обрушения здания в Нигерии [2]. Кроме того, есть исследования, указывающие на то, что низкое качество строительства и плохое управление также являются одними из причин дефектов зданий [3]. ...
This paper presents a novel deep learning framework specifically tailored for the identification of structural defects using high-resolution remote sensing data. Central to this approach is a supervised learning method that employs a comprehensive training dataset to discern the intricacies of various structural defects. A subsequent post-processing step utilizing a Markov Random Field (MRF) model ensures the assignment of optimal labels, allowing for a more accurate differentiation between defect and non-deffect regions in the observed scenes. Quantitative evaluations and experimental results highlight the effectiveness and potential of this method in the realm of structural defect detection.
... Damage assessment is an indispensable process in the field of civil engineering. It entails assessing the severity and extent of structural damage, infrastructure, and buildings caused by natural disasters, accidents, or other events [1][2][3][4]. The necessity for damage assessment in civil engineering may be seen when there are fatalities from sudden accidents. ...
... In the Support Vector Classifier (SVC) module of the SVM, data sets derived from the experimentation data are employed during both these phases. The information is then classified as undamaged (0) and damaged (1). The mean is calculated using the gathered data and provides the foundation for training and testing. ...
... The study revealed that a total of 225 buildings collapsed due to various reasons, with construction and maintenance flaws being the most common factors contributing to the failures. Another research conducted by Olanitori [3] focused on building collapses in Nigeria over different time periods. According to the study, 30 Garg et al. [4] presented a study on bridge failures in India, reporting that over 2130 bridges collapsed between 1977 and 2017. ...
The field of structural health monitoring (SHM) has gained significant attention from academia and industry, particularly in the realm of damage detection. This approach allows continuous monitoring of the structural integrity of systems and structures throughout their operational lifespan, leading to reduced dependence on periodic inspections and lower maintenance costs. Importantly, this method enables the assessment of structural degradation without causing actual damage to the structure itself. Over the past four decades, various evaluation methods for SHM have been developed, with concrete buildings benefiting greatly from their implementation. Among these methods, vibration-based techniques provide a quick and efficient way to assess the overall health of a structure. Specifically, frequency-based techniques are commonly employed within the vibrations-based SHM (VBSHM) framework, although extracting these parameters through algorithm development can be a complex and time-consuming task. This research aims to review VBSHM with a focus on modal parameters, exploring both traditional and modern methodologies to enhance the accuracy of structural assessment. Additionally, the study highlights the current limitations of research in this field and identifies available studies for further exploration.
... The rate of structural failure and collapse of buildings has raised global concern and there is now a demand for a lasting solution [3]. The causes of these failures especially in developing countries such as Nigeria are attributed to poor structural designs by non-professionals (quacks), use of substandard materials [4], [5], negligence of the use of appropriate personnel in building construction supervision, poor workmanship/supervision and most importantly the ineffective use of structural health monitoring (SHM) data [6]. ...
... The beams in the building have the lowest average rebound compressive strength of 33.2 compared to the columns and slabs which have 42. 3 and 42.5 respectively (Figs. 15 and 16). The values of the beam and slabs are spread away from the mean value while the values for the column strength are spread close to the mean value showing a standard deviation of 2.1 and a coe cient of variance of 4.9% (Table 9). ...
This research explores the use of non-destructive equipment (Schmidt Rebound Hammer) to investigate the state of reinforced concrete buildings. A total of 138 Slabs, 266 Beams and 210 Columns were assessed as structural elements spread across six (6) different buildings. The columns, beams and slabs for the residential buildings have overall mean rebound compressive strength of 26.15 N / mm ² , 20.18 N / mm ² and 32.2 N / mm ² respectively. For the institutional buildings, the overall average rebound compressive strength for the columns, beams and slabs is 25.71 N / mm ² , 27.22 N / mm ² and 34.92 N / mm ² respectively. The columns, beams and slabs for the industrial buildings have overall mean rebound compressive strength of 30.27 N / mm ² , 24.23 N / mm ² and 39.87 N / mm ² respectively. Rebound compressive strength values reduce as the height of the building increases. The standard deviation and coefficient of variance for a set of structural elements in the buildings showed high level of uncertainties and disparities which is an established factor in the use of the rebound hammer. This is a clear indication that a more robust method of analysis is needed for the interpretation and drawing of conclusions from the rebound hammer assessment.
... The rate of structural failure and collapse of buildings has raised global concern and there is now a demand for a lasting solution [3]. The causes of these failures especially in developing countries such as Nigeria are attributed to poor structural designs by non-professionals (quacks), use of substandard materials [4], [5], negligence of the use of appropriate personnel in building construction supervision, poor workmanship/supervision and most importantly the ineffective use of structural health monitoring (SHM) data [6]. ...
... There are few incidents of structural collapse due to lack of maintenance and construction faults worldwide. For example according to author, Olanitori [1] there were 42 buildings collapsed from 1976 to 2006 in Nigeria. Kumalasari Wardhana [2] has presented information about the building failures in United States from 1989 to 2000 and major reasons for the failure of these 225 buildings are majorly due to construction faults, maintenance deficiencies and natural calamities like rain, wind, snow, vehicular impact, and collision. ...
Structural health and condition assessment have become an important part of infrastructural life, due to continuous deterioration caused by nature or human activities. It ensures public safety and saves the economy if carried out properly. Even though deterioration is the natural process of a structure, the rate depends on the functional utility and its maintenance. So, poor maintenance of commercial structures, public buildings, and historical constructions can lead to major damages to sudden collapse. There are several methodologies to predict the health of the structures like destructive, Non-destructive, and sensor-based evaluations, but there is a huge scarce of experienced engineers in interpreting and evaluating the condition of the structures. In this paper, an attempt is made to help engineers in a robust way with fast-moving models to predict the condition at a global level of the structure using Machine Learning for the data obtained from Non-Destructive Tests (NDT) which are in general carried on local level structural elements. In conclusion, a model is proposed which connects between local elemental properties to global behaviour.KeywordsStructural Health AssessmentNon-Destructive TestingMachine LearningConcrete structuresCompressive strength
... The quantity of study on SHM has increased dramatically in last ten years, as seen by the huge rise in papers published on the subject. The necessity for this topic issue stems from the growing interest in SHM and its potential for major life-safety and economic advantages due to sudden failures of structures all over the world [3][4][5][6]. ...
Recent advancements in sensor technology, as well as fast progress in internet-based cloud computation; data-driven approaches in structural health monitoring (SHM) are gaining prominence. The majority of time is utilized for reviewing & analyzing the data received from various sensors deployed in structures. This data analysis helps in understating the structural stability and its current state with certain limitations. Considering this fact, integration with Machine Learning (ML) in SHM has attracted significant attention among researchers. This paper is principally aimed at understanding and reviewing of vast literature available in sensor-based data-driven approaches using ML. The implementation and methodology of vibration-based, vision-based monitoring, along with some of the ML algorithms used for SHM are discussed. Nevertheless, a perspective on the importance of data-driven SHM in the future is also presented. Conclusions are drawn from the review discuss the prospects and potential limitations of ML approaches in data-driven SHM applications.KeywordsStructural health monitoringData drivenMachine learningVibration-basedVision-based
... Recently, the Nigerian construction industry has faced many challenges, of which defects and collapse of buildings are inclusive. Most building defects and collapses ensued mainly due to non-compliance of the construction industry's professionals to the national standard on selected construction materials (Windapo and qualified professionals (Olanitori, 2011). Studies have shown that the Nigerian building construction industry is dominated by informal construction activities, in which operations are not professionally monitored. ...
... As stated earlier, cement acts as a binding agent in concrete (Odigure, 2009). Cement grade is a significant factor that contributes to concrete quality (Olanitori, 2011). It is essential in determining the compressive strength of concrete. ...
... This is usually among quacks that rely on experiences from previous similar projects where stability was achieved and sustained. This finding aligns with Olanitori (2011), who linked building collapse to the inappropriate placement of steel reinforcement. Many professionals in the industry rarely use admixtures except in extreme situations; this could account for using superplasticisers as concrete admixtures. ...
The incessant collapse of high-rise buildings has necessitated research into the compliance of materials — structural components and elements — to standards. This study evaluated compliance of concreting materials with standards in building project delivery. It examined the factors that influence compliance with standards of materials used for producing concrete elements. A quantitative approach was adopted in the study where structured questionnaires were administered to designers and constructors (such as architects, engineers/site supervisors and quantity surveyors) in consulting and contracting organisations in Lagos State, Nigeria. The data were analysed using frequency distribution, mean score, standard deviation, factor analysis and Kruskal Wallis test. Factors affecting compliance of materials with standards were categorised into construction site-based and procurement-based. These are technical, regulation, procurement, capacity, performance, and skill. The study provides implications for quality building production through improved compliance of concreting materials to standards. It also found the neglect of the use of structural engineers' services and limited standards observance on site. These lead to substandard components and elements production. It, therefore, recommends efficient regulatory policies, enforcement mechanisms, improved training and instilling ethical standards among project stakeholders. . Keywords – Building projects, Compliance, Concreting materials, National standards, Project delivery
... On the basis of this, the soils except MCS fall into the category and therefore they have good potential in the construction industry as they will be suitable for use as road sub-base material. Furthermore, various authors have affirmed that lateritic soil might be useful as landfill liners if the fine component is greater than 30% [13,[21][22][23][24][25][26][27][28][29][30] . Thus, all the studied soils are useable as landfill in sanitary. ...
... This is because of the ability of these soils to absorb high moisture. Both the amount of swelling and magnitude of swelling pressure are known to be dependent on the clay minerals, the soil mineralogy and structure, fabrics and several physic-chemical aspects of the soil [24][25][26] . Based on the free swell test result shown in Table 1, the studied soil samples with the exception of sample MCS, tend to be non-expansive. ...
This study investigate the geotechnical and mineralogical properties of differently sourced lateritic soils in order to determine their suitability for engineering construction purposes. In addition, attempts were made to establish the relationships between mineralogy and some geotechnical/engineering properties. Five lateritic soil samples derived from quartzite, mica schist, amphibolite, sandstone and migmatite-gneiss in parts of the southwestern Nigeria were collected in the field for geotechnical tests as well as determine their mineralogical compositions using x-ray diffraction (XRD). Result from grain size analysis shows that the soils are generally fine to medium grained consisting mainly of clayey silty sand. The Atterberg consistency limits revealed that the soils contain inorganic clay of low to intermediate plasticity, with linear shrinkage limit between 7% and 10%, indicating medium shrink potential. Based on the Skempton's activity chart, the soil can be classified as active to moderately active soils. The maximum dry density values of the samples at standard proctor energy of compaction range from about 1.46 g/cm 3 to 1.96 g/cm 3 , while those obtained at modified proctor energy vary between 1.57 g/cm 3 and 2.09 g/cm 3. The shear strength tests give angle of internal friction between 31 o and 33 o and cohesion values ranging between 59kPa and 70kPa for the standard and modified proctor compaction, respectively. These values indicate that the soils will have high bearing capacity and could support a moderately steep slope. The coefficient of permeability of the soils is low with k ranging from 0.7 x 10-8 m/sec to 8.79 x 10-8 m/s, which falls within the range considered to be impermeable. The soaked and unsoaked California Bearing Ratio (CBR) values vary from about 1% up to 6%. Based on the geotechnical analysis, the soils can be used as liners in landfill system, fill materials in embankments and earthfill dam construction as well as subgrade and fill materials for road pavement in highway construction. The mineralogical analysis showed that the soils are mostly composed of illite, kaolinite, quartz, feldspar, hematite and goethite.
... The quantity of study on SHM has increased dramatically in last ten years, as seen by the huge rise in papers published on the subject. The necessity for this topic issue stems from the growing interest in SHM and its potential for major life-safety and economic advantages due to sudden failures of structures all over the world [3][4][5][6]. ...
Recent advancements in sensor technology, as well as fast progress in internet-based cloud computation; data-driven approaches in structural health monitoring (SHM) are gaining prominence. The majority of time is utilized for reviewing & analyzing the data received from various sensors deployed in structures. This data analysis helps in understating the structural stability and its current state with certain limitations. Considering this fact, integration with Machine Learning (ML) in SHM has attracted significant attention among researchers. This paper is principally aimed at understanding and reviewing of vast literature available in sensor-based data-driven approaches using ML. The implementation and methodology of vibration-based, vision-based monitoring, along with some of the ML algorithms used for SHM are discussed. Nevertheless, a perspective on the importance of data-driven SHM in the future is also presented. Conclusions are drawn from the review discuss the prospects and potential limitations of ML approaches in data-driven SHM applications.
