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Land Procurement for Public Interest Against Destroyed Land: Natural Events and Legal Certainty
Based on a case study on the construction of the Semarang-Demak Toll Road, this study aims to investigate and investigate land acquisition for the public interest for land that has been destroyed as a result of natural events and its legal certainty. The research method used is socio-legal with primary data in identification, field measurements, and other supporting data. Semarang-Demak Toll Road property acquisition demonstrated tidal inundation on the north shore. Subsidence exacerbates Semarang's flooding. On flooded land, sea dikes and retention ponds prevent tidal floods. If just for transportation, the Semarang-Demak Toll Road can be built in flood-free areas or over the sea, like Bali's Mandra Toll Road. Land acquisition concerns delayed the Semarang-Demak Toll Road. Lack of land limitations has delayed land purchases. In the Semarang-Demak Toll Road land acquisition, destroyed land is not a problem under Indonesian law. 2021's Regulation 18 defines destroyed land. Destroyed land will drive people to take better care of their land and be more concerned about global warming or land subsidence. The state honors the landowner's emotional connection by paying for spiritual care. Doi: 10.28991/CEJ-2022-08-06-06 Full Text: PD
Applications of Nearest Neighbor Search Algorithm Toward Efficient Rubber-Based Solid Waste Management in Concrete
Indeed, natural processes of discarding rubber waste have many disadvantages for the environment. As a result, multiple researchers suggested addressing this problem by recycling rubber as an aggregate in concrete mixtures. Previously, numerous studies have been undertaken experimentally to investigate the properties of rubberized concrete. Furthermore, investigations were carried out to develop estimating techniques to precisely specify the generated concrete's characteristics, making its use in real-life applications easier. However, there is still a gap in the conducted studies on the performance of the k-nearest neighbor algorithm. Hence, this research explores the accuracy of using the k-nearest neighbor's algorithm in predicting the compressive and tensile strength and the modulus of elasticity of rubberized concrete. It will be done by developing an optimized machine learning model using the aforementioned method and then benchmarking its results to the outcomes of multiple linear regression and artificial neural networks. The study's findings have shown that the k-nearest neighbor's algorithm provides significantly higher accuracy than other methods. This kind of study needs to be discussed in the literature so that people can better deal with rubber waste in concrete. Doi: 10.28991/CEJ-2022-08-04-06 Full Text: PD
Punching Shear Strength Prediction for Reinforced Concrete Flat Slabs without Shear Reinforcement
Failure of flat slabs usually occurs by punching shear mode. Current structural codes provide an experience-based design provision for punching shear strength which is often associated with high bias and variance. This paper investigates the effect of adding a horizontal reinforcement mesh at the top of the slab-column connection zone on punching the shear strength of flat slabs. A new equation considering the effect of adding this mesh was proposed to determine the punching shear strength. The proposed equation is based on the Critical Shear Crack Theory combined with the analysis of results extracted from previous experimental and theoretical studies. Moreover, the equation of load-rotation curves for different steel ratios together with the failure criterion curves were evaluated to get the design points. The investigated parameters were the slab thicknesses and dimensions, concrete strengths, size of the supporting column, and steel ratios. The model was validated using a new set of specimens and the results were also compared with the predictions of different international design codes (ACI318, BS8110, AS3600, and Eurocode 2). Statistical analysis provides that the proposed equation can predict the punching shear strength with a level of high accuracy (Mean Square Error =2.5%, Standard Deviation =0.104, Mean=1.0) and over a wide range of reinforcement ratios and compressive strengths of concrete. Most of the predictions were conservative with an underestimation rate of 12%. Doi: 10.28991/CEJ-2022-08-01-013 Full Text: PD
Co-valorization of Tuff and Sandy Residues in Roads Construction
In recent years, the use of local materials in pavements has developed to compensate for the lack of normalized standard materials in the Algerian arid regions. The main objective of this research is to assess the co-valorization of two local materials to design a road material with satisfactory characteristics. In this context, the use of tuff in combination with sand residues is explored. The evolution of the characteristics of tuffs mixed with sand residues according to percentages ranging from 0% to 50% is highlighted. The used materials were subjected to physical and mechanical tests. Then, a series of mechanical tests were carried out on mixed samples compacted at the optimal characteristics that were deduced from the modified Proctor test. The obtained results highlight the existence of an optimal formulation composed of 70% tuff and 30% sandy residues, which presented an unconfined compressive strength (UCS) of 5.16 MPs and a CBR index (CBRI) of 42.6 %. Moreover, the results show clearly the evolution of the measured characteristics with time (drying) and without the addition of binders. The possibility of the use of studied mixtures in pavements has been verified regarding the recommendations in use (CTTP 2001) and the Saharan Road Technique (SRT). Doi: 10.28991/CEJ-2022-08-05-013 Full Text: PD
Seismic Pounding Response of Neighboring Structure using Various Codes with Soil-Structure Interaction Effects: Focus on Separation Gap
Due to the high cost and less availability of land, the buildings are constructed adjacent to each other with a significantly smaller separation gap. Whenever seismic forces act on adjacent structures, they collide and cause significant structural and architectural damage. Soil-Structure Interaction (SSI) effects cause more complications in the adjacent structures. This paper assesses the gap distance between RC bare frame adjacent structures of varying heights in medium and soft soil with and without SSI to avoid the pounding effect of an earthquake. The main objectives are to find the separation distance between adjacent buildings by the provisions of FEMA 356, IS 1893 (Part 1):2002, IS 1893 (Part 1):2016 and EN 1998-1:2004. The separation gap between different codes was then compared to determine the minimum separation required to prevent pounding between the structures. The maximum lateral displacement on the roof and the time period of the adjacent buildings are compared with and without SSI. There is a significant increase in lateral displacement, separation distance, and time period considering SSI. It is found that the Indian code overestimates the separation distance. Thus, this study guides structural engineers to maintain a minimum separation distance between buildings erected on medium and soft soils in high seismic zones of India. Doi: 10.28991/CEJ-2022-08-02-09 Full Text: PD
Rehabilitation of Hybrid RC-I Beams with Openings Using CFRP Sheets
This research presents an experimental investigation of the rehabilitation efficiency of the damaged hybrid reinforced concrete beams with openings in the shear region. The study investigates the difference in retrofitting ability of hybrid beams compared to traditional beams and the effect of two openings compared with one opening equalized to two holes in the area. Five RC beams classified into two groups, A and B, were primarily tested to full-failure under two-point loads. The first group (A) contained beams with normal weight concrete. The second group (hybrid) included beams with lightweight concrete for web and bottom flange, whereas the top flange was made from normal concrete. Two types of openings were considered in this study, rectangular, with dimensions of 100í—200 mm, and two square openings with a side dimension of 100 mm. A full wrapping configuration system for the shear region (failure zone) was adopted in this research. Based on the test results, the repaired beams managed to recover their load carrying capacity, stiffness, and structural performance in different degrees. The normal concrete beam regains its total capacity for all types of openings, while the hybrid beams gain 84% of their strength. The strength of hybrid concrete members compared with normal concrete is 81 and 88% for beams of one opening and two openings, respectively. Doi: 10.28991/CEJ-2022-08-01-012 Full Text: PD
Multidimension Analysis of Autonomous Vehicles: The Future of Mobility
The level of investment in AVs technology has been increasing over the years as both researchers and developers are cooperating with the objective of developing AVs and understanding their behaviors and implications. Despite the enthusiastic speculation about AVs, little is known about the implications of AVs on our lives and the intertwined relationships between the implications. Thus, the main objective of this paper is to reveal the benefits and risks of AVs and sketch out the main trends in this area in order to provide some directions and recommendations for the future. This study focuses on analyzing the impact of AVs on the required fleet size, vehicle utilization, cost of mobility, public transit service, public behavior, transportation network, land use, economy, environment, society, and public health. Furthermore, the paper analyzes the intertwined relationship between the implications of AVs. Additionally, the paper sheds light on the potential benefits and challenges of the deployment of AVs in developing countries. The analysis shows that while AVs offer multiple benefits, they also pose new risks. The degree to which AVs can affect our plant mainly depends on regulatory actions, as the broader implications of AVs are mainly dependent on how the technology will be adopted, which can be controlled by regulatory actions. Doi: 10.28991/CEJ-SP2021-07-06 Full Text: PD
High Strength Concrete Beams Reinforced with Hooked Steel Fibers under Pure Torsion
A study of the behavior of fibers in high-strength reinforced concrete beams is presented in this paper. Twelve reinforced concrete beams were tested under a pure torsion load. Different compressive strengths (45.2, 64.7, and 84.8 MPa) and fiber volume fractions (0, 0.25, 0.5, and 0.75) with variable spacing between transverse reinforcements have been used. It was discovered that the maximum torque of a high-strength concrete beam is increased by about 20.3, 25.6, and 27.1% when the fractional volume of fiber is increased from 0 to 0.25, 0.5 and 0.75 respectively (when the compressive strength is 45.2 MPa and the transverse reinforcement spacing is 100 mm). The test results show that the ultimate torsional strength becomes higher when the concrete compressive strength increases, and this percentage increase becomes higher with increasing steel fiber volume fraction. When the spacing between transverse reinforcements decreases from 150 to 100 mm, the ultimate torque increases by 19.9%. When the spacing between transverse reinforcements decreases from 100 to 60 mm, the ultimate torque increases by 17.0%. In these beams, the fibers' compressive strength and volume fraction were kept constant at 45.2 MPa and 0.75, respectively. Doi: 10.28991/CEJ-2022-08-01-07 Full Text: PD
Slenderness in Steel Fibre Reinforced Concrete Long Beams
Slenderness influences in steel fibre reinforced concrete (SFRC) long beams are not adequately addressed in current concrete design regulations. The present guidelines are confined to semi-empirical formulations for limiting slenderness ratio, but largely restricted to RC beams. Many scholars have already examined RC long beams and successfully presented the slenderness ratio formula for RC long beams. This article proposes a novel term for limiting the slenderness ratio for SFRC long rectangular beams based on the fundamental principle of mechanics and taking into account the slenderness impact of RC long beams as well as the flexural moment capacity of SFRC beams. The suggested formulation for limiting slenderness ratio agrees closely with experimental data and may reliably forecast the mode of collapse. The proposed limiting slenderness ratio formulation takes into consideration beam end circumstances, loading conditions, concrete strengths, steel, tension and compression reinforcement ratios, and transverse reinforcement ratios, among other factors. It is revealed that a wide variety of slenderness limits may be achieved for varied sets of design parameters. The researchers' predictions and the suggested equation are compared to the test results of 9 SFRC beams. The suggested equation fits well with the results of the tests that have been done so far. Doi: 10.28991/CEJ-2022-08-06-011 Full Text: PD
Impact of Climate Change on Crops Productivity Using MODIS-NDVI Time Series
Climate change is the single biggest threat facing the global food system. Irrefutable impacts of climate change on the food systems are recently acknowledged. Therefore, extensive scientific efforts around the globe are dedicated to investigating and evaluating the short and long-term effects of climate change on the development of global food systems. In this study, an integrated approach of two methodologies, including Moderate Resolution Imaging Spectroradiometer (MODIS) Data and Normalized Difference Vegetation Index (NDVI), was employed to extrapolate the long-term changes in agronomic areas from 2000 to 2020 in the Dukan Dam Watershed (DDW), Northern Iraq. The link between agricultural areas and the primary production of essential crops (Wheat, Barley, Rice, Maize, and Sunflower) is proposed to be altered due to the impact of climate change. According to the Intergovernmental Panel on Climate Change (IPCC) report, Iraq is one of the semi-arid regions in the world that has recently been characterized by water scarcity and limited agronomic areas. Three independent variables (rainfall, temperature, and agriculture area) were used in the multiple regression analysis to understand the impact of the main drivers affecting the production of crops in DDW. Obtained results showed an increasing trend in crop production as a result of the frequent use of groundwater and surface water sources along with the implementation of greenhouse cultivation. Correlation analysis shows that the crop production was significantly related to the annual precipitation with a 59–63% in winter crops like wheat and barley, but was less sensitive to the temperature with a 20–40% in summer crops like rice, maize, and sunflower. Doi: 10.28991/CEJ-2022-08-06-04 Full Text: PD