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.

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.

The impact of Manufacture sand on UPV, compression strength and modulus of rupture has been experimentally investigated and discussed in this paper. Concrete grade 30 (30Mpa) were produced with different percentage of M sand substitution ranging from 25%, 50%, 75% and 100% by volume were selected as concrete mix design in this project. The strength for different percentage of M-sand incorporation was measured by the destructive test which are compression strength test and modulus of rupture test and nondestructive test which is UPV test for curing ages of 90, 28 and 7 days. Furthermore, the highest compression strength of concrete and modulus of rupture was found on the 90th day containing a proportion of 75% of M-sand as a substitution for natural fine aggregate. A novel empirical equations 1 & 4 are proposed for the relation of compression strength with the modulus of rupture and UPV.