The natural sand which excavated from river bed is used to produced conventional concrete. Depletion of natural sand cause the environmental problem and hence sand excavating is restricted by government which resulted in shortage and drastically increase in its cost. In order to fulfil the necessity of fine aggregates, an alternative material like M sand can be used in concrete. M sand is obtained by crushing the rocks. In this paper, conventional mix 1:2.32:2.82 (M20) with water to binder ratio is maintained as 0.55 was used in this present study. Here the River Sand is partially and fully replaced with M Sand with different percentages like 0%, 45%, 50%, 55% and 100%. Fresh and hard concrete properties were studied with natural sand substitute by M-Sand. Properties of concrete in fresh state such as workability and in hardened state such as compression test, split tensile test and flexural test were considered in this study.

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High amount of reactive silica is ubiquitous in pozzolanic reaction for concrete strength increment. Rice husk ash (RHA) is proven contains high content of amorphous silica that is essential in the pozzolanic reaction of effective additive in concrete. Nevertheless, incorporation of RHA as cement replacement material (CRM) or additive is very minimal in current concrete industry. Therefore, improvement on the RHA properties by introduction of thermal and chemical pretreatment prior to incineration process is considered as a promising way in order to achieve the goal. This treatment process has been reported widely in literature. In this paper, the effect of treated rice husk ash (TRHA) and non-treated rice husk ash (NTRHA) incorporated mortar in terms of its compressive strength and microstructure properties are examine subsequently. The strength activity of TRHA from the optimum treatment process was measured by testing the compressive strength of mortars. The highest compression value obtained was 50.73MPa with 3% UFTRHA replacement at 28 days. At a longer curing period i.e. 90 days, it was recorded that 3% of UFTRHA mortar had the highest compression value at 53.87MPa. As for microstructure properties, a denser microstructure with excellent aggregate bonding and cement matrix in the interfacial transition zone (ITZ) was observed.

This, research work was to study the potential of M-sand as compared to river sand in concrete, here M-sand is replaced by river sand 0%,45%,50%,55% and 100% in the concrete mix, Mix design is designed as per IS Standards. In this research a mix 1:2.32:2.82 (M20) was considered. The test specimen was casted for 7days, 28 days and 90days. The performance of M-sand was determined by several experiments such as slump test, impact strength test, flexural Strength, and compressive strength test. The results attained from each test states that as M-sand increases the slump value decreases. flexural strength, compressive strength and impact test of concrete at 7 days, 28 days and 90 days is greater at 100% and 50% replacement of M sand by river sand.

This paper investigates the effects of the properties of fresh concrete incorporating shredded Polyethylene Terephthalate (PET) bottles and Manufactured Sand (M-sand) together as fine aggregates replacement in concrete mixtures. The investigation to determine the correlation of the fresh properties of concrete were mainly experimental based and the experiments involved were Slump Test, VeBe Test and Compaction Factor Test. There were two different concrete batches were prepared, in which the first batch was partially replaced by M-sand and the second batch was partially replaced by M-sand and shredded PET bottles as fine aggregate replacements. The proportion of M-sand content and M-sand with shredded PET bottles were 25%, 50%, 75% and 100% (for M-sand) and 1.5% proportion of shredded PET bottles respectively. The mix design was prepared in accordance to the Department of Environment (DOE) method and utilizes M30 as the Class of Concrete. A novel empirical relationship between slump, VeBe, and compaction factor for the shredded PET bottles and M-Sand based M30 concrete was proposed. The outcomes of this research has proven beneficial to the construction industries as the utilisation of waste and recycled materials has the potential for sustainable construction.

A measure of how easy it is to transport, cast, compact and surface finish of fresh concrete without any segregation is directly proportional to workability of concrete. The consistency of fresh concrete indirectly measures its workability. VeBe test, slump test and compaction factor test are some of the methods that can be used to study the consistency of concrete. A quick determination of the concrete strength and fresh properties is an important element on large construction sites for mass concreting to save time and cost. It is important to develop a machine learning model to predict the strength and workability of concrete with the help of available data. This paper aims to develop the machine learning model with the help of experimental data such as slump, VeBe and compaction factor of concrete incorporated with shredded Polyethylene Terephthalate (PET) bottles, Manufactured Sand (M-sand) and River sand as fine aggregates replacement in concrete mixtures. The machine learning model is developed by using different machine learning techniques such as Multiple Linear Regression (MLR) and Decision Tree Regression (DTR). As per the results obtained the DTR model is performed well than MLR model.

Urbanisation have given significant impact on escalating the traffic volume as the tremendous traffic congestion daily, especially during peak hours in weekdays. The objective of this paper is to assesses the impact of on-time performance towards quality of urban bus services in Malaysia. Therefore, this study was conducted at 11 state capitals in Peninsular Malaysia. The main local bus terminals had been designated in this study. The Transit Capacity and Quality of Service Manual (TCQSM, 2013) was chosen as the guideline used in this study. The results showed that Johor Bahru recorded a total 648 departure daily which considered the highest departure. There were 4 state capitals that recorded more than 80% of overall on-time departure for each route, such as Kuala Terengganu (94.39%), Shah Alam (82.45%,), Ipoh (80.74%) and Kangar (80.06%). The overall quality of services for on-time performance in state capitals of Peninsular Malaysia was classified as QOS D. Based on the study results, several rectifications on bus services in state capitals of Peninsular Malaysia is highly required.

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