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The present research was performed aiming to develop gel with the characteristic of reversible thermosensitive in adsorbing heavy metal ions from its solution. There were three gels used in this study to adsorb heavy metal ion from salt solution provided Zn(NO3)2; copolymer gel consisting of zwitterionic betaine N,N-dimethyl(acrylamidopropyl)ammonium propane sulfonate (DMAAPS), N,N-dimethyl(acrylamidopropyl)ammonium butane sulfonate (DMAABS), and DMAAPS copolymerized with thermosensitive N-isopropylacrylamide (NIPAM) gels. The aforementioned gels were employed to examine its ability in adsorbing and swelling after being synthesized through free radical polymerization before being affected by methylene spacer number, copolymerization, and temperature given. This research found that as the temperature increases, the ability of the gel in adsorbing the ions decreases. In the case of DMAAPS and DMAABS gel, the swelling degree value increases when the temperature also increases. Meanwhile, sulfobetaine which has larger spacer has higher adsorption ability but not with its swelling degree. In spite of having more spacer than DMAAPS, DMAABS found to have the smallest swelling degree value. In addition, NIPAM-co-DMAAPS was found to have both the highest adsorption ability and swelling degree value. Even though copolymer has less amount of sulfobetaine than DMAAPS and DMAABS gels’, the copolymer gel was found to have higher ability of adsorption as many as ten times of other gels.

Roads are made up of both pavement and off pavement components. In many cases, only road pavement is subjected to maintenance, leaving out accessory road components even though these components also contribute to overall road performance. Hence, the assessment of both road pavement and road components is vitally important in keeping roads safe and enhancing their overall performance. This study was conducted to know the performance of a select road as well as relevant handling recommendations. The research was carried out on 16 road sections of Magetan Regency, East Java Province with a total length of 85.60 km. The Kabupaten Road Management System (KRMS) Software was used in gathering precise road performance information. Weighting of road components was done using AHP (Analytical Hierarchy Process) while priority handling was determined using Analysis Network Process (ANP) with Super Decision software. A camera was used for the observation of both road and off pavement conditions. From research results after analyzing 16 Straight Line Diagrams, all road segments were in good condition. However, routine maintenance recommendations have been provided after a 16 Strip Map Diagram analysis of road segments. The first priority is Genengan-Lembeyan road segment followed by the Tamanarum-Lembeyan road.

There are two methods of road assessment, ie, visually and using tools. Visual assessment makes use of the PCI (Pavement Condition Index), while assessment with the Roadroid app can be used to obtain the value of IRI (International Roughness Index) with less cost. Functional assessment of roads in the field more use of visual methods. This method is influenced by the subjectivity of surveyors. Therefore, the assessment using the visual method should be correlated with the assessment method using tools, in order to reduce the subjectivity of road assessment. The research location used is Magetan District Road consisting of 5 road segments. The result shows that the r road assessment using the PCI method has a very good condition, and using IRI Roadroid has a Medium condition. There is a negative (r) correlation between PCI and IRI Roadroid, valued at -0.23. The negative correlation shows that both judgments reversed. Comparison of PCI assessment with IRI Roadroid has a low correlation value and with ttest, yields no comparison of correlation. This result is because the PCI and IRI equally assess the pavement, using different methods.

This paper presents the results of creep tests of Laminated Veneer Lumber Sengon (LVL Sengon) beams, aiming to determine the creep factor and to establish the prediction beam deflection based on the initial creep test data. The LVL Sengon beams have a cross section of 40 mm by 80 mm and a clear span length of 2,000 mm, they were loaded at midspan for three different stress levels: 30%, 40%, and 50% of the ultimate load within 30, 60, and 90 days. Each loading level consists of four repetitive beams where one beam was wrapped with a plastic sheet. The test results showed that for 90 days the bending creep test can not determine the secondary creep yet. Curve fitting of bending creep test data indicated that the parameters of the Modified Burger creep model of the first 30 days can be accurately used to predict the beam deflection curve up to 60 and 90 days of loading.

Kedung Uling earthfill dam locates at Wonogiri Regency, Central Java, Indonesia. The dam encountered sliding and settlement at the embankment wall. To minimize sliding and settlement and to optimize the dam, both field investigation and laboratory tests have been proceeded for slope stability analysis and remedial embankment wall. Soil and rock investigation around the dam, which is followed by 10 core drillings, have been conducted. Laboratory tests such as direct shear and index properties have also been carried on. The results were further used for dam slope stability model using slide 6.0 and were used to analyzed factor of safety (FS) of Kedunguling dam. 10 conditions of dam were simulated and strengthening body of dam with grouting was designed. The results showed two conditions, which are condition of maximum water level with and without earthquake at downstream, were unsatisfy Indonesia National Standard (SNI) for building and infrastructure. These conditions can be managed by using grouting for increasing stabilization of embankment wall. By setting up grouting, factor of safety increases and meet the SNI standard requirement.

The 10 mm thick Aluminum 6061 plates have been corner joined using varied design and those were 45° Corner Butt and Corner Lap Joints (CB-45 & CL). Friction tool was hardened EMS 45. True experimental method was used with independent parameters is feed rate which varied at 10 mm/min, 15 mm/min and 30 mm/min respectively. Other parameter such as rotating speed was kept constant. Experiment results show that, CB-45 yields better properties than CL. The tensile strength of CB-45 reaches 163.7 MPa for 10 mm/min feed rate. Whilst CL produces joint with tensile strength equal 120 MPa for equal parameters. Microstructure observation showed that CB-45 produces fine and homogenous appearance of MgO compared to CL. This phenomenon is caused by the pin of CB-45 joint which fully penetrates the nugget zone which is not found in CL design. This microstructure in turn promotes higher tensile strength of CB-45.

Irrigation water shortages have the potential to limit agricultural development otherwise arable land. To resolve such irrigation water shortages, accurate evaluations focusing on the assessment of the irrigation system’s physical condition, the functionality of the infrastructure components, and the irrigation efficiency are all needed. The assessments of physical condition and functionality are metrics used to establish the performance index value of the irrigation system. The performance index value can be used to identify sections that need maintenance and to define the level of damage that has impacted the irrigation network infrastructure. The irrigation network’s overall performance is analyzed based on the weight of each criterion as defined in the Minister of Public Works Regulation No.32 Year 2007. This research location is Tlatak Irrigation Area, in the District of Parang, Magetan Regency. The results of the analysis showed that the efficiency of irrigation was 74.24%, and the irrigation system performance was only 61.11%. These numbers indicate that the Tlatak irrigation network is categorized as ‘Requiring Attention.' Efforts should be made to resolve the irrigation issues by conducting periodic maintenance, constructing one or more deep wells, and enhancing the role of the Water User Farmers’ Association.

Sustainable construction is a topic that emerges in the world construction as a response to climate change issue. Building construction stage is a stage in sustainable development. Construction concept that confirm to the concept is referred to as green construction. Precast concrete construction is a construction system that meets green construction criteria, because applies the usage of material and construction method that optimize energy consumption and minimize environment impact during construction. This paper describe the qualitative and quantitative research in precast structures as green construction in Indonesia. Qualitative research was conducted on the assessment criteria of Green Building Council of Indonesia (2012-2014). The quantitative researches are in energy consumption and environmental influence of several construction systems which were conducted at low cost housing construction in Batam (2011-2012). Finally the research (2013-2014) and application (2015-2017) of high performance earthquake resistant precast concrete structure at low cost in Indonesia is described. The result of this research is expected to be a contribution to all construction stakeholders, in order to start to consider optimization of energy consumption in construction, and to become part of sustainable earth movement.

The welded joint always contains the microstrain when welding is complete. The microstrain generates distortion and changes of the physical shape of the weld joint. The purpose of the study was to observe the pattern and direction of residual stress before and after welding Q900&T125 and Q900&T175 Steel. The materials used for this study is Hot Rolled Plate Steel made by Indonesia steel industry. Method of this study is 1. Q900&T125 and Q900&T125 Steel machined in V-butt joint. This joints weld by using manual gas metal arc welding, Q900&T125 and Q900&T125 Steel weld joint can be found. 2. Measuring the distance from the lattice planes before and after welding by using Neutron-Ray Diffraction. Then the microstrain can be found. By involving Poisson numbers and modulus of elasticity of material in microstrain obtained residual stress. All the pattern of microstrain is compressive stress and leads to the weld center.

Kedung Uling earthfill dam is located between Eromoko and Wuryantoro district, Wonogiri Regency, Central Java, Indonesia. Water leaked from the dam was found and could decrease volume of dam. The objectives of this study are to identify piping and to recommend for solving piping problem. In order to determine the piping direction and litological pattern, investigation of 10 boreholes with various depth has been carried out. This investigation aim to determine characteristics of soil and rock by analyzing 45 cm of thickness of undisturbed samples and to perform permeability test. Permeability test have been conducted by falling head method with 3 different depths. Leaking at the dam was analyzed by Slide 6.0 software. The results indicated that litology of dam have been identified as claystone, sand and tuff. The piping passed under the eastern abutment of the dam is the accumulation of groundwater in the aquifers formed by 8-10 meters thick layer of sand. The total debit of piping is 17,774 cm3/sec. The Factor of safety of piping is under the minimum of standard namely 3,6. Grouting is one of alternative method to minimize the piping. Grouting was simulated to reduce permeability value and increase soil strength. By grouting, the total debit of piping was reduced to 3.314 cm3/sec.

An aeroelastic interaction always take places in long-span bridge, i.e. the dynamic relationship between wind forces (aerodynamic) and bridge structural motion (dynamics). Wind forces may lead to serviceability and safety problems, and may even cause instability of the whole bridge structure due to the flexibility nature of long span bridge structures.The slimer girder plate will make the structure more unstable as can be seen from the occurrence of lateral deformation. This paper presents the results analysis of cable stayed bridge that has total span of 640 m, two planes configuration of harp-typed hanger cable, the A shape pylons span along 320 m (main span),and side span of 160m. Structural analysis was conducted to determine the optimum ratio between width and spans of cable stayed bridge. The bridge was modeled with various width of 7 to 22 m. Structural modelling was conducted using SAP2000 software to analyze the structural stability of cable stayed bridge under wind load at speed of 35 m/s.The influence of wind loads to the cable stayed bridge stability can be seen based on the bridge deck deformation at the Y-axis (U 2 ), in which for the width of the bridge deck of 7 m, 8 m, 9 m and 10 m, the deformation of U2 are 0.26 m; 0.17 m; 0.12 m and 0.10 m, respectively. Meanwhile, for bridge’s width of 11-22 m, the value of U2 axis deformation is relatively constant between 0.08 m to 0.07 m. This finding suggests that the ratio between width and length of bridge greatly affect the stability of the cable stayed bridge. Cable-stayed bridge, especially for concrete bridge, with two plain system having optimum ratio of width and length show no sign of an aerodynamic instability when fulfills the requirements of B ≥ L / 3.

Data examination regarding historical earthquakes in Indonesia has revealed that damages occurred mostly in non-engineered buildings. Many non-engineered buildings have serious design and construction deficiencies in using concrete of inadequate quality and have poor steel reinforcement detailing especially in their beam-column joints. These joints require an effective strengthening technique which is simple to install. This paper presents steel plates to reinforce concrete beam-column joints through numerical studies. The finite element model was developed using ABAQUS. The FEM results were validated by comparisons with previous experimental tests. For this purpose, two RC beam-column joints were analyzed, including original standard beam columns and non-standard steel detailing strengthened with steel plates. The comparison of the results from numerical model indicated that steel plates could increase lateral strength, ductility, energy dissipation and increase the shear strength of the joints.