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Construction cementitious materials or construction-based materials, such as cement paste, mortar, and concrete, are one of the most utilized materials in building construction today. This material's advantages include its high compressive strength, durability, lower labor costs, and applicability to a wide range of building applications. In its use, this material is susceptible to shrinkage, which produces a decrease in the material's volume because of reduced moisture content and loss of water during the hardening process. In a mixture of cement-based construction materials with a low water-cement ratio, superabsorbent polymer (SAP) is known to be one of the materials with "healing agent" capabilities. In addition, the usage of this material can automatically cover cracks. This study aims to examine the use of superabsorbent polymer in improving the durability of cement-based construction materials, as well as the problems that could occur if this material is applied in Indonesia. Several techniques, including data collection techniques, data reduction, data analysis, data presentation, and drawing conclusions, are used to conduct a literature review. The result of this research is a literature review on the definition of SAP, its durability, and its challenges in Indonesia. [ABSTRACT FROM AUTHOR]

Self-healing concrete (SHC) is a concrete material innovation which can cure a crack on the concrete by microorganism supplementary as a healing agent. Besides, plastic is a material frequently utilized, yet it increases the amount of plastic waste in environment. Thus, the plastic waste has been developed as a synthetic fiber inside the concrete. Plastic waste supplementary in SHC has potential in increasing mechanic characteristics on the concrete. However, research discussing plastic waste substitution in SHC has been uncovered. This research aimed at analyzing load strength value ability accession, elasticity modulus, strength of tensile, and evaluation result resulted from crack cover of SHC Bacillus subtilis bacteria based with the substitution of plastic waste on the concrete was normal. This study employed experimental method by utilizing two compositions of concrete: A's composition (bacteria concrete and plastic fiber) and R (normal concrete). Both of compositions later would be molded consisting of 3 cylinders 150×300 mm and 3 prism 75×75×150 mm. Next, the treatment was undertaken for 28 days before testing. To evaluate the crack, the tested concretes were placed into three different treatments; indoor, outside, and immersed on water. Furthermore, the research showed the elasticity modulus value, and it decreased up to 7.75%, compared with normal concrete. The crack closure evaluation showed that crack closure in concrete by immersed on water by coverage as calcium carbonate sediment in the crack area on the 14th and 28th compared with other treatment. [ABSTRACT FROM AUTHOR]

The reinforced concrete beam structure plays a role in receiving bending force and shear force so that it will undergo deformation during loading. In order to maximize the performance of the beams, reinforcement is added to help in withstanding tensile stresses because the concrete is weak against tensile. If the deflection arising from large loading results in the servisability of the beam is also less comfortable. For this reason, the rigidity of the beam needs to be designed so that the deflection of the beam can be limited. Realizing the importance of rigidity to the behavior of structures, the researchers conducted research on the behavior and characteristics of graded concrete beam. This research was conducted to determine the effect of singly and doubly reinforcement configurations on the rigidity of graded concrete beam. There were six specimens in this study. Each specimen is formed with two concrete mixtures, namely 20 MPa and 40 MPa with a beam shear span ratio of 2.5. Testing was performed numerically using the FEA application. The results showed that the behavior of single-reinforced and double-reinforced graded beams was between their control beams. Then, the double reinforced configuration on the gradation beam results in higher rigidity than the single reinforced gradation beam with an increase of up to 27.51%. The deformation ability of double reinforced gradation beams has increased by up to 38% than that of single-reinforced gradation concrete beams. In addition, with a double reinforcement configuration, the curvature of the gradation concrete beam is reduced to -2.19%. The design of the double reinforcement configuration is more recommended as a reinforcement for gradation concrete beams in subsequent studies. [ABSTRACT FROM AUTHOR]

The expected failure of the structure is an important parameter to consider when designing reinforced concrete beams. The magnitude of tensile and compressive stresses due to loading, which is determined by the reinforcement configuration, has a large influence on structural failures. The addition of reinforcing steel can improve the resistance of reinforced concrete beams to tensile stress, but it reduces the beam's ductility. On the other hand, in recent years, reinforced concrete innovation has been developed in an effort to optimize the performance of beams by grading the quality of concrete. In comparison to normal concrete beams, reinforced graded concrete beams (RGCB) exhibit more complex behavior. Based on this, this study was carried out to investigate the effect of single and double reinforcement on RGCB. In the modeling, RGCB with concrete quality of 40 MPa on compressed fibers and 20 MPa on tensile fibers was modeled. The beam geometry is b=179 mm, h=358 mm, and the a/d ratio is 2.5. All specimens of the test object are designed with a low rebar ratio in the expectation that the beam will be ductile. The study's findings are as follows: (1) the crack pattern created on the RGCG resembles a higher quality control concrete beam; (2) RGCB experience bending failure in the middle of the span followed by shear failure; (3) the use of different concrete strengths in RGCB creates an unsustainable cracking pattern; and (4) the use of double reinforcement on RGCG shows more distributed strain propagation compared to RGCG with single reinforcement. [ABSTRACT FROM AUTHOR]

Concrete is the largest contributor to carbon emissions in the construction sector. However, recently there have been no studies analyzing embodied carbon in normal concrete with specific reviews on one structural element and reinforced concrete buildings with variations in structural configuration. The purpose of this study is to determine the influence of material variables and designs of reinforced concrete beam and reinforced concrete buildings on the value of embodied carbon which can then be used as a consideration of low-emission building design. This research was conducted using parametric analysis methods using Building Information Modeling-based applications and ICE Cement, Mortar, and Concrete Model – V1.1 Beta. Reinforced concrete beam were designed with single reinforcement with minimum and maximum reinforcement ratio and in cross-sectional dimension ratios, namely 1:3, 1:2, and 2:3. Reinforced concrete buildings were designed with 3 variations of column elevation, namely 3000 mm, 3500 mm, 4000 mm, and 3 variations in beam span, namely 3000 mm, 4000 mm, 6000 mm. The results of this study show that the greater the ratio of width to height of the beam (b/h) and the reinforcement ratio, the higher the embodied carbon produced. The denser and higher the elevation of the column used, the greater the embodied carbon produced. In reinforced concrete buildings, the cradle-to-gate stage produces embodied carbon by 49.69%, the construction stage by 2.93% and End of Life by 4.39%. [ABSTRACT FROM AUTHOR]

Based on the empirical equation, the calculation of the bearing capacity of the pile foundation is influenced by the characteristics of the soil indicated by the cone resistance and friction (CPT) and the SPT value. However, determining the bearing capacity is also influenced by the material parameters of the foundation used. Based on SK SNI T-15-1991-03 [1] and ACI 363-92 [2], the determination of the concrete elasticity modulus is influenced by density, concrete compressive strength, and the correction factor. The value of this parameter can affect the bearing capacity and the settlement. Based on this, this study analyzes the behavior of driven single concrete piles at a diameter of 400 mm on the downward and uplift bearing capacity and the settlement with the variation of concrete compressive strength. This parameter can affect the elasticity modulus and the density of the material. The analysis was carried out using the Allpile program and empirical equation. The pile was reviewed at depth of 8 meters on clay soil. The results show that the downward bearing capacity is not affected by the weight, density, concrete compressive strength, and elasticity modulus (pile parameter material). Meanwhile, the result of the uplift bearing capacity is influenced by the alteration in the weight and density which affect the compressive strength and elasticity modulus. The value of the elasticity modulus affects the settlement of the foundation. The relationship that results in a corresponding point between weight, settlement, and uplift bearing capacity occurs approximately at 2.78 kN/m, 0.032 cm, and 94.6 kN. [ABSTRACT FROM AUTHOR]

Connections are often one of the causes of structural failure. The connection structure using cold-formed steel material has been widely studied using 180°straight rod. This study used type C and 90° upright connection. The test objects were joints in various shapes. This study aimed to determine the tensile strength, length increase, and damage with connection in various shapes. This study consisted of six test object variations; each had three repetitions. The variation consisted of rod built in back-to-back and hollow profiles. The second variation was the connection form, consisting of without lip connection, continuous plate, and elbow plate. The cold-formed steel was formed in an I-shaped letter and pulled using UTM. The obtained results were the greatest tensile strength can be held by the rods which are assembled back to back with L plate connection. Back to back connection of rods affects the tensile strength of CFS rods, even though they have the same cross-sectional area. Connection using L plate produces greater tensile strength and less deformation. [ABSTRACT FROM AUTHOR]

Cobalt oxide synthesis with difference stirring time is rarely highlighted because it is considered to have little effect when, in fact, the stirring time influences the final product. Cobalt oxide has multiple applications since almost all modern technologies that use nanotechnology use cobalt oxide with an easy example is the manufacture of the electrodes in supercapacitors. Cobalt oxide in this study was synthesised using the sol-gel auto combustion method with stirring time variations of 15 minutes, 75 minutes, and 135 minutes. The analysis of phase identification and crystal size used XRD. The morphological analysis used SEM, analysis of functional group bonds used FTIR, and three secondary data were used as amplifiers to determine the specific capacitance value. The smallest crystal size of cobalt oxide in this study was 21.2872 nm at a stirring time of 15 minutes with the final sample having a single phase. The synthesised samples' morphology using the sol-gel auto combustion method appeared to have low agglomeration and porosity levels. Based on the FTIR testing, there was a double absorption peak in the fingerprint region, namely 569–671 cm−1. Based on the three secondary data observed, cobalt oxide's specific capacitance values ranged between 235 F/g, 391.4 F/g, and 430.6 F/g. From this statement, comparing each factor, and the obtained results from other studies, it showed that the synthesised cobalt oxide in this study had the feasibility and potential to be applied in the manufacture of the electrodes of a supercapacitor. [ABSTRACT FROM AUTHOR]

Graded concrete technology could be the best solution to promote the green building concept in the construction industry. The failure behaviour and flexural strength of a RC beam are influenced by various factors, including beam dimension, number and arrangement of reinforcement bars, the shape of the beam cross-section, properties of steel and concrete, and beam span ratio. In this research, the researchers intend to conduct further studies related to the behaviour of graded concrete (GC) beam using various cross-sectional dimension ratios and rebar ratios. This study used 8 (eight) GC beam specimens which mainly made of two concrete mixes, namely the concrete strength of 40 MPa and 20 MPa. The cross-sectional dimension ratio used is 2/3 and 1/2. Two types of rebar ratios were examined which are minimum rebar ratio (0.35% and 0.45%) and maximum rebar ratio (1.59% and 4.78%). The flexural test was carried out by the four-point bending method. The results show that the change in cross-sectional dimensions from 2/3 to 1/2 increases the ultimate load capacity to 62.47% and the deflection decreases to 48.72%. Furthermore, the change of rebar ratio increases load-carrying capacity up to 118.59% and decreases the deflection up to 52.40% along with the increase in the rebar ratio. In the future, it is recommended to design a GC beam using a ratio of 1/2 in cross-sectional dimensions and using a minimum rebar ratio with the respect to the higher concrete strength as the reference. [ABSTRACT FROM AUTHOR]