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The building to be utilized should undergo regular inspections and performance testing to determine whether it can function and operate according to its intended use. Compliance with administrative and technical regulations governing the utilization of buildings is demonstrated through the issuance of a Building Worthiness Certificate (SLF). This study aims to assess the compatibility of the building's function with the conditions during the planning phase and evaluate the structural feasibility of the building. It also seeks to implement the provisions of Government Regulation No. 16 of 2021 regarding the Implementation of Law No. 28 of 2002 on Buildings. Based on the research conducted, it can be concluded that the structural suitability of the MSC Indosat Baturaden building has changed compared to the planned building. Initially designed as a battery storage building, it is currently used as an MSC building or a facility for storing batteries and servers. Additionally, there are discrepancies in the area specified in the original Building Permit (IMB) compared to the current building. Further analysis of the building's structure and the application of current regulations regarding structural serviceability, including dynamic load analysis (earthquake), inter-story drift analysis, P-Delta analysis, and structural cross-section checks, concluded that the building is safe as it meets the requirements specified in SNI 1726:2019 and SNI 2847:2019. The highest structural cross-section capacity ratio was 0.2 < 1, and the inter-story drift value was 0.023 < 0.07. The existing concrete material meets the structural standards, with a characteristic compressive strength of 28.98 MPa. The results of the rebar scan detector test showed that the type of reinforcement used complies with the standards specified during the planning phase, referring to SNI 07–0408–1989. Overall, the structural analysis results for the MSC Indosat Baturaden building indicate that the building is safe and remains fit for use.    

Water absorption test and compressive strength test were conducted to determine the quality standards of paving blocks. This research was conducted by using a mixture of fly ash, bottom ash and cement. The tests carried out in this study were water absorption test and compressive strength test using 3 compositions of 5%, 8% and 12%. In each composition using 3 samples for testing. Tests were carried out with a vulnerable time between 7 days, 14 days and 28 days. The highest water absorption results in the 8% composition with water absorption of 1.467%. The highest compressive strength results in the 8% composition with a compressive strength of 10.479 Mpa.

Indonesia is an area rich in sea sand. The aim of this research is to determine the comparison of the compressive strength of mortar derived from sea sand and river sand, as well as the feasibility of using sea sand as a material in construction in coastal areas. The results of the research showed that the compressive strength of the mortar from the two materials tested at 28 days had a difference in compressive strength of up to 37.45%, the mortar made from sea sand aggregate produced a mortar compressive strength of 14.13 Mpa which can be categorized as type S mortar with minimum value 12.5 MPa, meanwhile, mortar made from fine river sand aggregate produces a mortar compressive strength of 22.59 MPa and is included in the type M mortar category which has a minimum value of 17.2 Mpa.  

Parepare City is located on the coast with significant fisheries and maritime potential. The processing and consumption of shellfish in this city produces a lot of shellfish waste, which is often not utilized and accumulates into an environmental problem. To improve the properties of concrete, several types of additives that have certain functions are added to the concrete mixture, namely increasing the workability, durability, and hardening time of concrete. This study aims to determine the compressive strength of concrete and the composition of coarse aggregate of shells with superplasticizer added materials that are optimally produced. Using an experimental method carried out at the Laboratory of Structure and Materials, Muhammadiyah University of Parepare. The results showed that substitution of coarse aggregate with 5% shellfish waste and 0.5% superplasticizer increased the compressive strength of concrete at the ages of 7, 14, and 28 days. The 10% substitution still meets the compressive strength requirements at 28 days, although slightly lower than normal concrete. Substitution of shells up to 5% increases the compressive strength of concrete, and the 10% content is optimal, reaching the maximum value without significant decline. It is recommended that the use of shells as a substitute for coarse aggregate does not exceed 10% for optimal results and meets the planned compressive strength of 25 MPa.

Increased economic growth in the city of Parepare with the presence of buildings around the estuary. In general, the composition of concrete making materials is taken from good materials. The problem encountered in the field is that the quality of concrete in construction decreases due to brackish water, causing structural elements in the construction to become porous. Meanwhile, preventive measures are rarely or never taken. As a result, the construction life is very short. Brackish water is one of the causes of structural failure. This is due to the content of sulfate and chloride ions in water containing salt/salts that react with chemical elements in reinforcing steel resulting in corrosion of the reinforcement. The purpose of the study was to analyse the compressive strength of concrete with a mixture of clean water against the percentage of brackish water with a maintenance age of 7, 14, 21, and 28 days. The results showed that brackish water had an impact on reducing the compressive strength of concrete due to the high chemical content in brackish water such as Sulfate (SO²¯) of 52.5 in brackish water in Kenjeran and 62.5 in brackish water in mangrove. Dissolved Solids (TDS) of 15188 mg/l in kenjeran brackish water and 3436 mg/l in mangrove brackish water. Organic Content (KMnO) of 8.05 mg/l in kenjeran brackish water and 6.69 mg/l in mangrove brackish water is too high, so the chemical content contained in brackish water can damage the compounds in the cement content and decrease the strength of the materials contained in the concrete. In this case it can result in concrete having a very low durability.

The development of concrete making technology has developed rapidly nowdays, the innovations in terms of material use and workmanship. The implementation of construction work carried out today pays attention to aspects of strength, rigidity, and high durability, as well as sustainability. To support these two things, research can be carried out on making concrete using granite waste. The research method used in this study is an experimental method. The concrete mix design uses variations of granite waste with successive levels of  0%, 15%, 30%, and 45%. The test specimen used for tensile strength testing is cylindrical with a diameter of 15 cm and a height of 30 cm, the test uses 12 specimens where each variation uses 3 specimens. The test is performed when the specimen has reached the age of 28 days. The test specimen tested has met the planned compressive strength requirements at a concrete life of 28 days where the results are greater than 20 MPa. Results of testing the tensile strength of concrete variations of granite waste as a partial substitution of coarse aggregate with variations of granite waste of 0%, 15%, 30%, and 45% respectively; 2.43 MPa; 2.50 MPa; 2.97 MPa; and 2.78 MPa.

The availability of sea sand on the beach of Ujung Tape Pinrang is in very large quantities that can be used as materials in making concrete. The purpose of the study is to analyze the characteristics of beach sand, compressive strength and tensile strength produced. An experimental research method in the Civil Engineering Laboratory, University of Muhammadiyah Parepare with a treatment system for ordinary water immersion and analysis of the characteristics of concrete mechanical properties using a compression machine test. The results of the study at the maintenance age of 28 days with a planned compressive strength of 20 MPa produced a compressive strength of 28.29 MPa and a tensile strength of 7.78 MPa, a planned compressive strength of 24 MPa resulted in a compressive strength of 29.98 MPa and a tensile strength of 8.22 MPa, and a planned compressive strength of 28 MPa produces a compressive strength of 31.40 MPa and a tensile strength of 8.44 MPa. The results of the study on compressive strength and tensile strength showed an increase in each increase in planned compressive strength.

In the process of designing mine slopes, drilling or tunneling, to determine the level of strength and brittleness factors of rock on a slope, it is necessary to carry out a uniaxial compressive strength test or indirect tensile strength test of the rock. Compressive strength testing is carried out to determine how long the rock maintains its strength or elastic properties when pressure is applied. This data can be used as information to understand the analysis of factors that influence the physical properties of rocks on the compressive strength of rocks from physical properties and compressive strength testing activities. and indirect tensile strength testing is carried out to determine the stress value contained in the rock. To determine the level of rock brittleness, it can be done by comparing the uniaxial compressive strength value and the indirect tensile strength value. This data can be used as information and reference for companies that will design a mine slope, drill and tunnel, how strong the strength and level of brittleness of rocks in areas dominated by sandstone. This research uses quantitative methods, so that to obtain accurate calculation data, testing methods are used in the form of uniaxial compressive strength tests and indirect tensile strength tests, in this case tested on sandstone samples obtained from 2 rock formations including the Pulaubalang formation and the Balikpapan formation, so that accuracy The test result values ​​can be obtained well. And after testing, a comparison is made between the uniaxial compressive strength test value and the indirect tensile strength test to obtain the Brittleness Index value.Based on the observation results, it can be concluded that when the brittleness of the rock becomes greater, the performance of the cutting digger increases several times.    

Uniaxial Compressive Strength is a test method to classify the strength and characterization of intact rock. Where it is important information in determining the strength and characteristics of a rock obtained by testing using the UCS tool. In this research, an alternative is made in determining the UCS value precisely and easily, namely by using the schmidt hammer test and compressive strength test. Therefore, this research aims to obtain the correlation value between the results of the compressive strength test and the schmidt hammer test on sandstone. Based on the results of observations and calculations that have been carried out, it can be concluded that the compressive strength value in the Balikpapan formation is lower than the compressive strength value in the Pulaubalang formation where the compressive strength value in the Balikpapan formation is 3.3 MPa-4.3 MPa, while the compressive strength value in the Pulaubalang formation is 4.3-5.57 MPa. The rebound number in the Balikpapan formation is lower than the rebound number in the Pulaubalang formation, where the rebound number in the Balikpapan formation is 16-17.8, while the rebound number in the Pulaubalang formation is 18-22.3. The correlation of the uniaxial compressive strength value with the rebound number of the schmidt hammer shows a positive linear correlation between the UCS value and the rebound number of the schmidt hammer, in this case it can be seen that when the uniaxial compressive strength value is higher, the rebound number of the schmidt hammer is also higher.

The current technology for using recycled materials in road preservation work is very helpful in maintaining the sustainability of the materials used. Waste from road materials that will be repaired can be reused for new foundation layers. The aim of this research is to obtain a design for the percentage of cement, percentage of emulsified asphalt, unconfined compressive strength and optimum water content in accordance with the applicable engineering specifications so that it can be proven that the existing material from the top foundation layer and asphalt layer can still be used as a new foundation layer. The research method involves conducting experiments on existing materials by conducting laboratory tests on samples of top foundation layer aggregate and existing asphalt in the Cikarang Industrial Area. The experiment was carried out at the Jakarta State Polytechnic Civil Engineering Laboratory with 9 test samples. The results obtained for the recycled foundation layer were that the design cement required was 30.8 grams and 53.1 grams of emulsified asphalt for an area of ​​1m2 with a 7 day unconfined compressive strength obtained from nine samples for variations in cement content of 1%, 3%, and 5% maximum 2.81MPa, so the optimum cement content is 3.6%.

To determine the mineral content and composition of a rock, a petrographic test is carried out using a thin section method. Petrographic test is known as an efficient test of time and energy with accurate results in obtaining the composition and mineral content of rocks. The Point Load test is an index test that has been widely used to predict the UCS value of a rock indirectly in the field. This is due to the simple test procedure, easy sample preparation and can be done in the field, so that the strength of the rock can be quickly known in the field before testing in the laboratory.

Rock strength has an important role in the mining industry. These forces can determine many aspects of mining such as slope geometry, excavation, blasting, and drilling. Rock strength can include tensile strength, compressive strength, and shear strength. In this case, the test is carried out to determine the correlation of uniaxial compressive strength and indirect tensile strength. The method used to determine the correlation of compressive strength and indirect tensile strength is by linear regression approach, which will then be analyzed for accuracy through Root Mean Square Error (RMSE), and Mean Absolute Percentage error (MAPE). This study used quantitative and qualitative methods, starting from the coordinate data of rock sampling locations, physical properties and mechanical properties. In this study, there were 6 sampling locations located in 2 different areas, namely Loa Janan and Sanga-sanga. The secondary data used are regional geological maps and maps of the area where the study is located. Furthermore, secondary data is processed using Arcgis software for mapping, and using Microsoft Excel software to assist in calculations in determining the value of physical and mechanical properties of rocks. The results of the compressive and tensile strength tests in this study showed a perfect corelation using linear regression, namely UCS= 3.9582 σt - 0.4004, with a correlation coefficient (R) of 0.972 and a determination coefficient (R2) of 0.945. and obtained RMSE 0.033 and MAPE 5.89%.

The uniaxial compressive strength value is one of the important parameters that is widely used in rock engineering projects in determining rock mass. The strength of rocks is greatly influenced by the water content and degree of saturation in the rock. Reduction of strength in rock is associated with an increase in water content, a slight increase in water content will cause a significant deviation in the compressive strength test value.This research is quantitative research, so to obtain accurate calculation data, testing methods are used in the form of compressive strength tests on rocks and physical properties tests in the treatment of samples of original rock, saturated rock and dry rock before testing. In this research, 2 types of rock were used, including limestone and sandstone in 2 rock formations, namely the Balikpapan formation and the Pulaubalang formation, so that the accuracy of the test result values ​​could be obtained well. Based on the results of observations and calculations that have been carried out, the water content values ​​of limestone in natural, saturated and dry conditions in the Balikpapan formation are obtained with average values ​​of 1.709%, 2.262% and 0.961% respectively. The water content of sandstone in natural, saturated and dry conditions is the Pulaubalang formation with average values ​​of 2.491%, 9.425% and 0.463% respectively. The UCS value of limestone in natural, saturated and dry conditions in the Balikpapan formation has an average value of 25.29 Mpa, 37.57 Mpa and 40.70 Mpa respectively. The UCS value of sandstone in natural, saturated and dry conditions in the Pulaubalang formation has an average value of 9,565 Mpa, 6,537 Mpa and 12,730 Mpa. It can be concluded that the correlation between uniaxial compressive strength values ​​and water content values ​​in limestone and sandstone shows a positive linear correlation, which means they have a strong relationship. The higher the compressive strength value of limestone and sandstone, the lower the water content value.    

Drilling capability, is one of the most important considerations in rock excavation, which can be defined as the ease of drilling a rock mass at a certain time for a long period of time with a drill bit. Rock drilling capabilities are influenced by various factors related to drilling machine working parameters and geotechnical characteristics of the rock mass (Yenice, 2019). Based on the above, this research was carried out to determine the UCS value in rock samples and the relationship formed by the DRI test value with the value produced in the UCS test using a regression analysis graph.    

Rock strength is the ability of a rock to maintain its strength until it breaks when a force is applied. Rock compressive strength is a very important parameter in the world of mining. The compressive strength of the rock determines the mining method that will be used. Several things that influence the compressive strength of rock include porosity, true specific gravity, and water content. With the same volume, if the porosity value is high, the true specific gravity value will be low because of the large number of pores in the rock. This allows the compressive strength value to be low because the rock will crumble more easily when pressure is applied. After testing, the highest compressive strength value was in the Pulaubalang Formation, location 2, with a value of 2.19 MPa. Meanwhile, the lowest compressive strength value was in the Kampungbaru Formation, location 1, with a value of 1.49 MPa. In accordance with the stratigraphic layers in the Kutai Basin, the Pulaubalang Formation is older than the Kampungbaru Formation.    

Uniaxial Compressive Strength is a test method to classify the strength and characterization of intact rock. Where it is important information in determining the strength and characteristics of a rock obtained by testing using the UCS tool. In this research, an alternative is made in determining the UCS value precisely and easily, namely by using the schmidt hammer test and compressive strength test. Therefore, this research aims to obtain the correlation value between the results of the compressive strength test and the schmidt hammer test on siltstone.This research is a quantitative research, so that to obtain accurate calculation data, testing methods are used in the form of compressive strength tests on rocks and schmidt hammer tests, which in this case are tested on siltstone samples. In this study, 2 rock formations were used, including the Pulau Balang formation and the Kampung Baru formation, so that the accuracy of the test results can be obtained properly.  Based on the results of observations and calculations that have been made, it can be concluded that the correlation of the uniaxial compressive strength value with the rebound number schmidt hammer value shows a positive linear correlation between the UCS value and the rebound number schmidt hammer value, in this case it can be seen when the uniaxial compressive strength value is higher, the rebound number schmidt hammer value is also higher.

This paper investigates the mechanical properties of eco-friendly concrete incorporating recycled aggregates and industrial by-products. An experimental program was conducted to assess the compressive strength, tensile strength, and durability of various concrete mixes. The results reveal that the use of recycled materials can produce concrete with comparable mechanical properties to conventional concrete. This study highlights the potential of eco-friendly concrete in reducing environmental impacts while maintaining structural integrity.

This research aims to determine the effect of adding the additive Sika Fume on the compressive strength of concrete. This research uses a type of quantitative research with experimental methods, namely by carrying out several tests on test objects in the laboratory. The results of this research show that the compressive strength of concrete with the addition of sika fume varies 0%, 3%, 5%, 7% and 8% of the cement weight, so the experimental results show that the average compressive strength at the age of 28 days of concrete has a variation of 0 % of 26.14 Mpa, 3% variation of 25.01 Mpa, 5% variation of 27.08 Mpa, 7% variation of 24.16 Mpa, 8% variation of 23.40 Mpa. The concrete compressive strength variation of 5% with an average of 27.08 Mpa is the variation with the highest compressive strength value and reaches the design compressive strength. Meanwhile, a variation of 8% with an average of 23.40 Mpa is the lowest compressive strength value and does not reach the design compressive strength.

Porous concrete has high porosity so that water can pass through the cavities in the concrete. The application of porous concrete is usually for parking areas, pedestrian sidewalks, road shoulders, drainage, roads with low traffic volume. Indonesia is an archipelagic country, most of Indonesia's territory is by the sea so it is very possible to use sea water as a substitute for fresh water for porous concrete. This research aims to determine the comparison of compressive strength of porous concrete mixed with sea water and normal porous concrete with variations in the water cement (fas) factor. In this study, a concrete mixture with a water cement (fas) factor of 0.30 and 0.35 was used. The test object used was a 15x30 cm cylindrical concrete test object for the compressive strength test. The test on porous concrete was carried out during the curing period of 28 days. The test results for the compressive strength of normal porous concrete with a water cement (fas) factor of 0.30 and 0.35 are 6.658 Mpa and 4.435 Mpa, then for porous concrete mixed with sea water with a water cement (fas) factor of 0.30 and 0, 35, namely 6,700 Mpa and 3,374 Mpa. The test results show that the sea water mixture in porous concrete does not affect the compressive strength of porous concrete, whereas the use of variations in the water cement factor (fas) shows that the compressive strength of porous concrete, both normal porous concrete and porous concrete mixed with sea water, has decreased. as the value of the water cement (fas) factor used increases.

PLTU produces coal-burning residues in the form of fly ash waste, which is constantly increasing. Fly ash is an industrial waste that is hazardous to the environment and human health but can be exploited because it has the characteristics of pozzolan. We conducted research on the use of fly ash as a cement substitute in the making of paving blocks. The aim of the research was to find out the strong pressure paving block method in British Standard 6717 with SNI 03-0691-1996 against the use of fly ash and how much of the fly ash is used against the strength of the optimum pressure. The research used an experimental method, with a comparison of 1 cement with 4 sand and variations in the use of air ash at 0%, 10%, 20%, and 30%. Tests were conducted when paving the block through the process of curing for 28 days. This study resulted in a strong average pressure paving block (PB) using the British Standard fly ash method 6717, with PB beam variations of 10%, 20%, and 30% in succession of 14.23 MPa, 13.49 MPa, and 11.14 MPa. While the SNI method 03-0691 1996 is PB cube variation at 10%, 20%, and 30%, respectively, of 12.27 MPa, 10.63 MPa, and 8.67 MPa. The strong result of pushing PB beams using the optimum fly ash is found at a 10% variation of 14.23 MPa and a 10% cubic variation PB of 12.27 MPa.