Use of Sea Sand as an Alternative to Fine Aggregate in the Construction Industry of Sri Lanka - A Review

Background/Objectives: In this study, the construction industries expect a serious shortage of sand in the near future due to over exploitation of river sand. This paper deals with the use of sea sand as substitute for conventional river sand. Methods/Statistical Analysis: M20 concrete mix was designed with sea sand as fine aggregate and the workability, strength in compression and split tension and water absorption characteristics are determined and compared with conventional concrete. Findings: The sea sand, as available, is inferior to conventional river sand but proper washing for two times make it feasible for making concrete. For M20 grade concrete, two times washed sea sand can be used as fine aggregate totally replacing river sand as the workability and strength characteristics reach within the limits of acceptable level. Sea sand utilization is cost effective in coastal line construction.

Concrete is a major construction material used in the construction now a days. It is a composite material containing cement, fine aggregate, coarse aggregate and water. Fine aggregate is required in large quantities for manufacturing of concrete. Generally river sand is used as a fine aggregate. Due to increase in the utilization of concrete in construction sector, the need for river sand has been increased enormously. Limitations have been laid on the large scale mining of river sand from river beds. In this context there are cases of illegal mixing of sea sand with river sand. This paper mainly presents the practical study of the compressive strength of the concrete in which sea sand was used as fine aggregate is partially or completely replaced. For this study first control specimens were laid for M20 grade concrete. The fine aggregate proportion from the design mix was replaced partially in percentages of 20%, 40%, 60%, 80% and 100% by sea sand. Compressive strength test was conducted on the various concrete specimens with various fine aggregate proportions and the results were tabulated. The compressive strengths of concrete specimens for respective mix proportions were tested at 7, 14 and 28 days of water curing. The behavior of concrete by partial replacement of fine aggregate with sea sand has been studied. With the increase in the percentage of sea sand replacement in concrete, the compressive strength of the concrete significantly reduced.

The carbonation behavior of seawater sea sand recycled aggregate concrete (SSRAC) was investigated in this study. Considering different added water, fine aggregates, and coarse aggregates, the specimens were divided into 12 groups for the accelerated carbonation test by 7 days, 14 days, and 28 days. Among them, river sand, sea sand, and mixed sand (the proportion of sea sand and shell sand was 4:1) were used as fine aggregates. The results show that the carbonation depths of concretes with different mixtures all increase over time. When the replacement ratio of recycled coarse aggregate (RCA) is not less than 50%, sea sand is the most suitable fine aggregate to acquire best carbonation resistance, while river sand is the worst. On the contrary, when the replacement ratio of RCA is not more than 30%, river sand is the most suitable fine aggregate, while sea sand is the worst. It can also be speculated that the most appropriate replacement ratio of RCA is 50% when sea sand is applied as fine aggregates in SSRAC. At the same time, 30% replacement ratio of RCA is appropriate when mixed sand is applied as fine aggregates in SSRAC.

Concrete is a composite building material made from a combination of aggregate and cement. The limitation of concrete material, in this case, is a fine aggregate (river sand). The utilization of sea sand as an alternative to fine aggregate in the manufacture of concrete is motivated by the availability of sea sand in nature in very large quantities. This study aims to determine the comparison and how much the compressive strength of concrete produced when using sea sand. The test was carried out when the specimens were 7, 14, and 28 days old with the specimens used in this study were concrete cylinders with a diameter of 15 cm and a height of 30 cm. The results showed that the use of sea sand as a substitute for fine aggregate showed an average compressive strength in 7 days of 18.86 MPa, an average compressive strength of 14 days of 25.52 MPa, an average compressive strength of 28 days of 29.00 MPa. Then for the average compressive strength value of the use of river sand in 7 days is 17.17 MPa, the average compressive strength of 14 days is 23.24 MPa, the average compressive strength of 28 days is 26.41 MPa.

Not all areas have sufficient resources for concrete needs. Coastal areas are areas that are difficult to obtain suitable sand for concrete needs. One of these coastal areas is Lontar Village, Kotabaru Regency, because of this, the people of Lontar Village, Kotabaru Regency, choose to use sea sand as a concrete material. The use of sea sand in Lontar Village, Kotabaru Regency is not subject to any treatment even though sea sand has a high salt content and uniform and fine grains, this can reduce the strength of the concrete. In this study, several treatments were carried out, namely no treatment, washing treatment and flush treatment, and using percentage variations of 0%, 30%, 50%, 70% and 100% sea sand. The parameters reviewed in this study were the compressive strength of concrete, split tensile strength of concrete and flexural strength of concrete.Concrete mix planning follows SNI 7626-2012. With untreated sea sand as a control, the sea sand treatment was followed by washing and flushing to reduce the salt content in the sea sand. Using several percentages of sea sand to add variety to the grain of sea sand. The treatment method used is fresh water immersion. The sample used was a mortar mixture in the form of a cube of 5 cm x 5 cm x 5 cm, and a concrete mixture in the form of a cylinder of 15 cm x 30 cm and a beam of 50 cm x 10 cm x 10 cm.The results showed that the highest compressive strength of mortar was in 30% sea sand washing treatment with 29.71 MPa. The highest compressive strength of concrete is at 0% sea sand with 20.38 MPa. The highest split tensile strength of concrete is at 30% sea sand with 1.92 MPa. And the highest flexural strength of concrete is at 30% sea sand with a flexural force of 3.05 MPa. Keywords: Sea Sand, Compressive Strength, Split Tensile Strength, Flexural Strength.

Investigation on behaviour of M-sand and sea sand based concrete

With the rapid development of urban infrastructure, building sand resources are increasingly scarce. China is rich in sea sand resources, which provides an alternative material for sustainable development. However, the effect of high chloride ion content in sea sand on reinforcement corrosion must be solved, which is the most important factor to popularize the use of sea sand. The electrochemical method was carried to investigate characteristic parameters of steel corrosion in concrete with sea sand and washed sea sand, under wetting-drying regime in which the 3.5% NaCl solution and sea water were selected as aggressive resource. The results show that the development of absolute corrosion potential has two steps, decrease first then increase, corrosion current density increase gradually with time. The development process of concrete with washed sea sand is obviously slower than that of sea sand concrete. The experimental results show that the corrosion characteristics of steel bars in desalted sea sand concrete vary obviously with time, and the electrochemical method is an effective method to investigate the corrosion of steel bars. Besides, the comparison experiment between river sand and desalted sea sand should be carried out to show the feasibility of desalted sea sand engineering application.

Abstract: Consumption of concrete has grown rapidly over a year, and it is also becoming one of the basic constructionmaterials. Since, it is a composite mixture of the constituents containing cement, fine aggregate, coarse aggregate and water. For manufacturing the concrete the fine aggregate are required more quantity. In general, river sand and RIVDER SAND is used as fine aggregate in construction industry. Due to this increase in use of river sand and RIVDER SAND the requirement has been increasing massively day by day in building sector. The government also have given some limitation on mining of river sand from the river beds. The treatment needed to remove the salt content in sea sand and sea water is difficult on time oftreatment and cost. So, the untreated sea sand is used in this test. The work on this study evaluates the different comparisons of mechanical properties of complete RIVDER SAND , complete sea sand (SS) and50% of RIVDER SAND with 50% of sea sand (MSSS). Main intention to consider the sea sand based concrete is to preserve the environmental resource in economical and sustainable development in construction and concrete sector. The experimental test results of sea sand based concrete shows adverse increase in strength compared to RIVDER SAND based concrete specimens

In this period of very scarce river sand resources for construction activities, the use of sea sand and salt-contaminated sand to replace river sand in roller-compacted concrete is necessary and suitable to the needs of actual demand. This article presents some research results on the possibility of using the sea sand of "Can Gio" to produce roller-compacted concrete for rural road surface layers. The roller-compacted concrete mix composition is designed according to ACI 211.3R standards with a fly ash-to-cement ratio by volume of 0.3. The required compressive strength value of the roller-compacted concrete sample is 27 MPa at the age of 28 days. The technical requirements of roller-compacted concrete using sea sand have been evaluated including the hardness of the concrete mixture, compressive strength, and abrasion resistance of tested concrete, using the ratio of sea sand- aggregate by volume ranges from 0.41 to 0.50. The study also compared the physical properties of "Can Gio" sea sand according to the technical requirements of standard TCVN 13754:2023 to provide recommendations when using salt-contaminated sand and sea sand for roller compacted concrete mixture.

This research was motivated by the use of sea sand to the availability of large amounts in Bengkulu city. The purpose of this study was to determine the quality of sea sand physically and to compare the compressive strength of concrete with the dunes and river sand. Sea Sand which were used in this study wereSelolongSea Sand, LakokSea Sand and Air Padang Sea Sand. The specimens were the cubical size 15 cm x 15 cm x15 cm of 40 samples with 2 types of treatment namely salt water and fresh water treatment. The planning of concrete used 0,5fasand 60-100 mmslump, The testing was done at 28 days. The result of this study showed that for doing the inspection of sand quality physically, all the tests fulfilled the requirement setexcept in the inception of sieve analysis for Air Padang sea sand, which has a very fine grain. The highestincreased of concrete compressive strength was atLakok Sea Sand, which was 3.86% of the dunes, and 4.77% for the treatment of river sand for freshwater. For the treatment of Lakoksalt water on the dunes increased to 2.22% and on the river sand increased 3.74%. Air Padang Sea Sand has the biggest reduction the compressive strength of concrete, most notably in the treatment of fresh water on the dunes of 10.33% and 9.54% of the river sand. For salt water treatment, Air Padang Sea Sand had a greater reduction which was 14.61% of the dunes and 13, 33% of the river sand.

Constructions across seashore increasing day by day (likely road pavements, bridges, hotels etc.,) But these are facing so many challenges by less availability chances of normal sand, water and huge amount of availability of saline sand, water. Sea water has 35ppt of an average salinity but in some places around shoreline salinity of ground water may vary from 0 to 35ppt due to humidity and temperature of ground surface. It will effect on durability of constructions at shore. In this investigation, the effect of saline content on M40 grade concrete(for road pavements)made by river sand and sea sand with partial and complete replacement of sea water specimen strength was studied. Total 216 specimens were casted using PPC cement in that 108 were casted using river sand and 108 were casted using sea sand with partial and complete replacement of sea water to test 7,14,28 days compressive & split-tensile strength of concrete specimens. Compressive strength test was conducted on cubes and Split-tensile strength was conducted on cylinders. PPC (fly ash based) cement is preferable for marine constructions due to its low heat of hydration and it has good resistance against saline attack. Sea water replaced as by 20%, 40%, 60%, 80% and 100% with normal water for different salinity ranges of water. Salinity was tested by Salinity Refractometer. River sand was collected from Vamsadhara River near srikakulam and sea water and sand was collected from kalingapatnam near srikakulam.

Nowadays there is a demand for river sand for construction. To avoid these conflicts, we are up to a solution of using sea sand along with granite granules as fine aggregate in concrete. Granite granules are the waste product obtained while cutting granite which is cost effective and sea sand is abundantly available in coastal areas when compared to river sand. This full replacement can be used in Plain Cement Concrete (PCC). Concrete cube is cast to test the compression strength for M5 grade concrete (since it is for PPC). As a result, strength is obtained related to cube cast using river sand in concrete. Using this result, we have figured out that granite granules can also be a better replacement with sea sand. Further studies are going on to use it in Reinforced cement concrete (RCC) by refining chloride from sea sand or by adding admixtures with concrete to prevent corrosion of reinforcement.

This study investigates the effect of using sea sand as fine aggregate on the compressive strength of concrete. The experimental research involved preparing concrete samples with varying proportions of sea sand, comparing their performance against conventional river sand. Compressive strength tests were conducted on the samples at 14 days, revealing that samples containing river sand exhibited significantly higher compressive strength than those with sea sand. The average compressive strength for concrete with 100% river sand was found to be 18.23 N/mm², while the presence of chlorides in sea sand, despite washing, adversely affected the strength. Statistical analysis confirmed a significant difference in strength between the control and sea sand mixtures. While sea sand presents an environmentally sustainable alternative, particularly in coastal regions, its use requires careful consideration of chloride content to prevent corrosion of steel reinforcement. This study concludes that sea sand can be a viable option for non-load-bearing or temporary structures, provided that appropriate measures are taken to mitigate potential risks.

SNI 03-6861-1-2002, states that the fine aggregate used in concrete structures should use river sand. However, the use of fine aggregate in Fakfak regency in general is still dependent on sea sand potential is quite large. The purpose of this study were: 1) determine the characteristics of sea sand in Fakfak regency as a component of the concrete mix; 2) determine the strength of concrete resulting from the use of sea sand. This research is an experimental research laboratory by means of sample testing and analysis of the characteristics of aggregates and concrete compressive test using a compression test machine. Results of testing the characteristics of fine aggregate to quarry in Fakfak regency consisting of quarry Kampung Seberang, quarry Kampung Sungai, quarry Tanjung Wagom and coarse aggregate from the quarry Kayuni can generally be used for a mixture of concrete for eligible characteristics of concrete aggregate but fine aggregate (sand) it is best to Tanjung Wagom quarry because of the fineness modulus 2.93 and included in zone 2. Compressive strength characteristics resulting from the quarry Kampung Seberang 122.84 kg/cm2 quarry Kampung Sungai 129.59 kg/cm2 and quarry Kampung Tanjung Wagom 144.27 kg/cm2 of the planned concrete quality 250 kg/cm2 or down 50.86% , quarry Kampung Sungai 48.16% and quarry Tanjung Wagom 42.29% down or strength is only reached at quarry Kampung Seberang 49.14%, quarry Kampung Sungai 51.84% and quarry Tanjung Wagom down 57.71%

A review on the physical & chemical properties of sea sand to be used a replacement to fine aggregate in concrete