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The building sector is a significant contributor to global carbon emissions, primarily due to the production of cement, a crucial construction material. The need for sustainable building practices has spurred research into alternative materials to traditional cement and sand. Two such materials, ultrafine coal bottom ash (uCBA) and spent garnet (SG), have shown potential as substitutes for cement and fine aggregate, respectively. This research examines the effectiveness of uCBA as a partial replacement for cement and SG as a partial replacement for fine aggregate in concrete, at varying levels of 3%, 6%, and 9% for uCBA and 10%, 20%, and 30% for SG. Initially, the chemical composition analysis was conducted using an X-ray fluorescence spectrometer (XRF), and the particle morphology of uCBA, OPC, and SG was examined through field emission scanning electron microscopy (FE-SEM). Then, the study evaluates the performance of these materials based on slump value, compressive strength, and splitting tensile strength, with specimens undergoing 28, 56, and 90-day curing periods. Results indicate that integrating uCBA and SG in concrete at levels of 3% and 10%, respectively, enhances compressive and splitting tensile strength while decreasing environmental impact. Moreover, workability improves with higher substitution levels. Overall, this research indicates that uCBA and SG hold great potential as replacements for cement and fine aggregate in concrete, providing a means to mitigate the environmental impact of construction.

Today, the subject of a building's resistance to lateral loads is one of the most important concerns of structural engineers. The partitions and infilled walls are non-structural elements that are important due to their effects on the lateral resistance of the building frame. Recently, it has been observed that great damage is occurring to infilled walls, partitions, and buildings in an earthquake-prone area. Infilled walls are effective at increasing the hardness and resistance of building frames, which changes the seismic properties of structures. Therefore, the study of interactions between the structural frame and the infilled walls is essential for a better understanding of structural behaviors. In this paper, the effect of infilled walls is investigated on the behaviour of steel frames using ABAQUS software. Modeling is carried out for different types of infilled materials, including brick and panel, as well as different thicknesses of the infills. It was observed that with an increase in the thickness of infills from 7 to 20 cm, the final capacity and energy absorption increased by 78%. Also, the panel-infilled frames have 18% more capacity and 3.8% more energy absorption than the brick-infilled frame in the same full state. As a result, panel-infilled frames outperform brick-infilled frames in terms of performance.&nbsp

Garnet is ideal for many commercial uses due to its potential to be recycled. The dumping millions of tons of spent garnet in landfills, quarries, oceans and waterways will cause the creating environmental concerns. In this study, spent garnet as a sand replacement is produced to innovate sustainable concrete. The research objectives are to study the effects of strength of spent garnet as sand replacement in concrete mix at high temperature and to evaluate its physical properties of spent garnet. Several laboratory experiments were conducted to determine the physical and its compressive strength before and after exposed to high temperature. Furthermore, the test for the physical properties that had been conducted were, specific gravity, bulk density and water absorption test. Other than that, the compressive strength of 30MPa at 28 days for trial mix design were prepared accordingly. The cube specimens of 100 × 100 × 100 mm were provided with substitution of 0%, 10%, 20%, 30% and 40% of spent garnet as sand replacement with 0.45 of water cement ration. All the concrete mixes containing spent garnet were produced slump of 30-60mm. Based on the test result, the cube specimen of 40 percent of spent garnet after heated started decrease in term of strength due to the present of the excessive of spent garnet particles in the concrete which can weaken the bond between aggregates and the cement paste. Thus, it reduces the concrete strength in term of less compaction of concrete has lower bonding strength.

Sand is the non-renewable resource which has been over-exploited from rivers in sync with the rapid development of construction industries to produce concrete. This affected the morphology of rivers and interrupted the functionality of riverine ecosystems by pollution. Meanwhile, the unrecyclable spent garnets were disposed of on a large scale and led to waste pollution. Therefore, this study aimed to determine the compressive and flexural strengths of concrete consisting of spent garnet as sand replacement. The specimens were prepared with consisting of spent garnet as sand replacement by weight in 0%, 10%, 20%, 30% and 40%. They were tested under compressive strength test at the age of 7 and 28 days while flexural strength test was conducted on the 28days. The findings revealed that the workability of fresh concrete was enhanced by an incremental amount of spent garnet. However, the compressive and flexural strengths of concrete consisting of spent garnet were discerned to be lower than control samples at all levels of replacement. Overall, the replacement with 20% spent garnet showed the optimum compressive and flexural strengths. It is concluded that the usage of spent garnet is considered as a promising resource for reducing consumption of sand and thus, improving the environmental problems.

This research studied the water absorption of concrete containing spent garnet and determine the durability of concrete containing spent garnet in acidic environment. The materials used along the experiment works were spent garnet, river sand, crushed stone, ordinary Portland cement and water. In this study, spent garnet were used as sand replacement with 0%, 10%, 20%, 30% and 40% in concrete mix designs. First and foremost, the water absorption test was conducted on three (3) set of water-curing cube specimens with dimension 100 mm cube for the plain concrete and for each percentage of spent garnet concrete mixes and was done in compliance with the BS 1881: Part122 (1983) specification. After that, the durability tests under 5% of hydrochloric acid attack and 5 % of sulphuric acid attack were conducted by preparing corresponding sets of concrete specimens which were three (3) set of 28 days water-curing specimens for each percentage of spent garnet in different acid immersion according to Standard ASTM C1898 – 20 while the compressive strength was under standard in BS EN:12390-3: 2019. In the end of the study, the physical appearances of the samples were observed and the weight loss for each sample was tested and recorded accordingly. From the results obtained, the highest percentage of water absorption of concrete was C20 which was 7.80%. However, the stronger average concrete strength of concretes from both acids with the achieved target compressive strength was concrete C20 but also with lowest weight loss. The concrete containing with 20% of spent garnet had better acid resistant in terms of visual assessment not only toward sulphuric acid attack but also toward hydrochloric acid attack. The application of 20% of spent garnet as sand replacement was hence can provide stronger acid resistant in maintaining the supporting strength of concrete. In conclusion, the durability of normal concrete should be investigated over a longer length of time to mimic the real-wo

Smart phones are an indispensable tool in modern day-to-day life. Their widespread use has spawned numerous applications targeting diverse domains such as bio-medical, environment sensing and infrastructure monitoring. In such applications, the accuracy of the sensors at the core of the system is still questionable, since these devices are not originally designed for high accuracy sensing purposes. In this thesis, we investigate the accuracy limits of one of the commonly used sensors, namely, a smart phone accelerometer. As a use case, we focus on utilizing smart phone accelerometers in structural health monitoring (SHM). Using the already deployed network of distributed citizen-owned sensors is considered a cheap alternative to standalone sensors. These devices can capture floors vibration during disasters, and consequently compute the instantaneous displacement of each floor. Hence, damage indicators defined by government standards such as peak relative displacement can be estimated. In this work, we study the displacement estimation accuracy and propose a zero-velocity update (ZUPT) method for noise cancellation. Theoretical derivation and experimental validation are presented, and we discuss the impact of sensor error on the achieved building classification accuracy. Moreover, in spite of the presence of sensor error, SHM systems can be resilient by adopting machine learning. Several algorithms such as support vector machine (SVM), K-nearest neighbor (KNN) and convolutional neural network (CNN) are adopted and compared. Techniques for addressing noise levels are proposed and the results are compared to regular noise cancellation techniques such as filtering.Finally, since most previous work focused on modelling the sensor chip error itself, we study other sources of error such as sampling time uncertainty which is introduced by the device operating system (OS). That type of error can be considered a major contributor to the overall error, specially for sufficien

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