One of the jobs that have a high complexity in civil works is foundation pile work. Practitioners are often faced with many choices and various conditions in the field in making decisions about the types of piles and ...
One of the jobs that have a high complexity in civil works is foundation pile work. Practitioners are often faced with many choices and various conditions in the field in making decisions about the types of piles and methods of piling. The selection of the type of piles and the method of piling will have environmental, economic and social impacts. Many conditions need to be considered when making this selection. This paper presents a literature review in the study of influence in the selection of pile type and foundation piling method in problem identification and approaches. The results of this study support the influence factor used by case studies of decision-making taking into triple constraint in project management.
Design and construction of road embankment presents several challenges, including the possibility of bearing capacity failure, large total settlement, differential settlement, and slope instability, which may result f...
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The foundation erection work is a job that has a high enough complexity. In making the decision of the type of pile and the method of erection, practitioners have many choices with various conditions in the field. Dec...
The foundation erection work is a job that has a high enough complexity. In making the decision of the type of pile and the method of erection, practitioners have many choices with various conditions in the field. Decision making will result in an impact during the foundation erection process. This study aims to analyze what are the impacts caused by the choice of pole type and piling method. A preliminary survey was conducted together with four experts to verify and reduce the 11 impact indicators obtained from the literature study, obtained 6 impact indicators which are quite relevant according to experts and will be used in the questionnaire survey. The questionnaire survey was conducted on 45 practitioner respondents who had carried out foundation building work. Data analysis validity and reliability tests were carried out on the questionnaire data. It was concluded that there were three main impacts that occurred due to the choice of the type of foundation pile and the piling method, namely environmental impact, economic impact, and social impact. The main impacts are broken down into six impacts including the use of fuel, ground vibration, fuel and material costs, equipment and labor costs, workplace safety, and noise.
This study focused on the modulus of rupture (MOR) for high strength self-compacting concrete (SCC) using varied metakaolin (MK) composition. The MOR significantly contributes to the resilience and mechanical performa...
This study focused on the modulus of rupture (MOR) for high strength self-compacting concrete (SCC) using varied metakaolin (MK) composition. The MOR significantly contributes to the resilience and mechanical performance of the rigid pavement, and is enhanced by modifying the regular concrete material. In addition, the MK is known to be potentially economical and occurs abundantly as natural resources. Plain concrete beams with dimensions 400 x 100 x 100 mm3, were tested in the laboratory in an effort to measure the MOR from varied MK composition for each specimen or modified concrete type. The result showed the MOR increase is exclusively as a result of additional metakaolin. Also, the newly modified material was proven to offer more advantages when applied as rigid pavement material. Furthermore, the analytical laboratory result showed the optimum MK dosage was estimated at 20% of the binder weight. This subsequently enhances the MOR by 17.28% compared to non-MK concrete.
An acidic environment commonly found in peat soils or expansive soil will harm the quality of rigid pavement by considering its use at long-life plan, traffic load, and minimization of damage to the crossroad due to v...
An acidic environment commonly found in peat soils or expansive soil will harm the quality of rigid pavement by considering its use at long-life plan, traffic load, and minimization of damage to the crossroad due to vehicle braking. As a concrete provider, chemical admixture as mixed materials today is widely used with the reasons of workability, initial strength, as well as saving of material used. This research aimed to find out the durability of concrete admixture using sika-NN and plastocrete (retarding and water reducing admixture) at the acid environment and knowing the displacement that occurred using ABAQUS software modeling. It used the laboratory experimental method and the cube concrete sample 15×15×15 cm with the compressive strength of 33.2 MPa. A total of 18 concrete samples were immersed using normal pH water and H2SO4 at pH 1 ± 1 tested at 3, 7, 14, 28, 60, and 90 days using the Duplo method. In this research, the concrete durability was carried out using, Ultrasonic Pulse Velocity Test (UPVT) to test the density, compressive test, and modeling concrete displacement on peat soils with vehicle loads in acidic environments using software ABAQUS. The mixed design results show an average setting time value of about 112 minutes. Coarse aggregate and cement decrease due to additives is approximately 24% and 18% respectively, increasing the use of fine aggregate to 16.49%, but the value of concrete density increases base on soaking time. Besides that, there is a decrease in compressive strength up to 16% at the age of 90 days. The value of displacement in the modelled pavement uses a maximum load of 8 tons each 2.994 mm for concrete with normal water and 3.045 mm for concrete with an acid environment respectively. Concrete soaked in acid water is the greatest deformation that occurred in rigid pavement using ABAQUS and indicates that acid water has an impact on decreasing concrete quality.
Synthetic zeolite is considered a more effective adsorbent due to its high purity and high removal efficiency. On the other hand, acid mine drainage contains various metal ions, such as zinc, copper, iron, and mangane...
Synthetic zeolite is considered a more effective adsorbent due to its high purity and high removal efficiency. On the other hand, acid mine drainage contains various metal ions, such as zinc, copper, iron, and manganese which are toxic for the ecosystem in a certain concentration. One of the solutions to remove these metal ions is through adsorption. Therefore, the study of adsorption and desorption of zinc and copper onto synthetic zeolite was conducted. The synthetic zeolite was synthesized from coal fly ash and the acid mine drainage was prepared artificially. The adsorption experiment was carried out using a batch system. NaCl, H2SO4, and HNO3 were used as desorption agent. The adsorption studies revealed that the removal efficiency of both Zn2+ and Cu2+ onto the studied adsorbent decrease with the increase of adsorbate concentration. While the adsorption selectivity for multi-system synthetic AMD solution by the studied adsorbent were found to the order of Fe2+> Cu2+> Zn2+> Mn2+.After being reused three times, the synthetic zeolite shows a decrease in for Zn2+ and Cu2+ adsorption efficiency of about 10%. Furthermore, the desorption study shows the ineffective use of NaCl, H2SO4, and HNO3 as desorption agents in this study.
Acid mine drainage (AMD) sludge is by-product from AMD treatment that formed by iron deposition. This sludge has a potential to be used as an active adsorbent to remove phosphate from domestic wastewater. The adsorben...
Acid mine drainage (AMD) sludge is by-product from AMD treatment that formed by iron deposition. This sludge has a potential to be used as an active adsorbent to remove phosphate from domestic wastewater. The adsorbent that was used in this research is AMD sludge from PT Bukit Asam Tbk., Tanjung Enim that majorly composed of Si, Fe and Al compound (determined by the XRD test). Phosphate adsorption was done by AMD sludge and MD sludge that was activated by hydrogen peroxide. Activation process by hydrogen peroxide affected the chemical and physic characteristic of sludge and it showed from the results that the concentration of Si, Fe and Al were shifted by 7.33%, 7.03%, and 1.49%, respectively. Meanwhile for the physical characteristic; specific surface area, pore volume, and pore size were shifted by 19.51 m2/g, 0.0635 cm3/g, and 142.694 nm, respectively. Phosphate removal by AMD sludge has a greater result than activated sludge. Adsorption capacity of AMD sludge was well described by Freundlich isotherm model, which is equal to 6.358 mg P/g. Meanwhile, adsorption capacity of activated sludge was well described by Langmuir isotherm model, which is equal to 0.48 mg P/g. Results in this study indicated that the activation process with hydrogen peroxide affects the ability of phosphate adsorption that was showed by the difference of removal percentage.
Acid mine drainage (AMD) treatment leaves residue in the form of sludge that contains large amounts of metal, silica, ferric, and alum. This research aims to determine the capabilities that AMD sludge-synthesized coag...
Acid mine drainage (AMD) treatment leaves residue in the form of sludge that contains large amounts of metal, silica, ferric, and alum. This research aims to determine the capabilities that AMD sludge-synthesized coagulant has in reducing COD and TSS concentration in domestic wastewater. The domestic wastewater sample used in this research is an artificial domestic wastewater with a COD concentration of 285 mg/l and a TSS concentration of 245.31 mg/l. After going through Acidification process, AMD sludge coagulant contains Si (43.66%), Fe (30.02%), dan Al (12.35%). A jar test is then performed in order to determine the optimal coagulant dosage. In this process, a coagulant dosage of 40 mg/; 60 mg/l; 80 mg/l; 100 mg/l; 140 mg/l; 180 mg/l; and 200 mg/l was used with 100 mg/l being the optimal coagulant dosage. The AMD sludge containing the optimal coagulant dosage of 100 mg/l is found to be able to reduce COD concentration by 34.74% and TSS concentration by 95.63% from the tested domestic wastewater sample. This research can illustrate the vast potential that the AMD sludge has as a coagulant.
Along with the increasing of infrastructure development in Indonesia especially in jepara, so the necessary of material also increase, for example: sand. Nowadays, muntilan is the sand that often be used in making inf...
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This paper presents a case study of reconstructing past landslide failure models in a napal geological formation by undertaking a series of geoelectrical tomographies and geotechnical bor-SPT surveys. study area is lo...
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