bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis of the feasibility of small-biomass power generation from the palm oil mill – study case: palm oil mill in Riau-Indonesia
Authors: Nuryadi Agus P , Pratomo Teguh B , Raksodewanto Alfonsus A
Published: October 2019

Solid waste from a palm oil plant in Indonesia is a tremendous potential for power generation, especially on Riau-Sumatra. The potential of electrical energy that can generate is determined by measuring or calculating the calorific value and amount of solid waste palm oil available. To be burned in the boiler continuously and more efficiently, the solid waste water content of palm oil must reduce to no more than 30%. The conservative substantial waste palm oil calorific value (HHV) is 3,500 kcal/kg. As a result, the mass and power plant balance are capable of producing a gross power of 4.6 MW using 80% efficient fluidised bed boilers and a steam turbine capacity of 5 MW with an isentropic efficiency of 85% with assumption percentages combination fibre: 30 % shell: 70 % fibre. The environmental impacts of power generation from empty fruit bunch (EFB) based on steam turbine generator technology evaluated. The results revealed that EFB utilisation for power generation is environmental friendly than fossil fuel power plants regarding global warming potential and acidification potential with GWP are 89.5 kg CO2 eq per MWh, and 0.515 kg SO2 eq per MWh. Also, the financial analysis of the Biomass Power Plant with a lifetime duration of 25 years, which the project is feasible to implement because IRR is 22.70%, higher than Weighted Average Cost of Capital (WACC) which amounted to 15.61%.
Regional heat capacity changes on oil palm plantation development in 1994-2010 based on Landsat-5 TM satellite data
Authors: Risdiyanto Idung , Ariyani Winda , Sujatnika Odjat
Published: October 2019

Regional heat capacity change is calculated from the ratio between the addition or subtraction of heat (ΔQ) with the increase or decrease in temperature (ΔT) region. The purpose of this study is to calculate the regional heat capacity change due to the changes of land cover composition with forest, shrubs, oil palm plantation and bare soil using Landsat-5 TM satellite data on 1994, 2000 and 2010. The total area used in this study is 12971 ha. In 1994-2000, 4 % of forest area and 2% shrubs were increased, followed by addition biomass forest 4.01 tons/ha and 2.83 tons/ha for shrubs. The increased of forest area and biomass (tons/ha) caused by forest and shrubs growth processing towards a climax that added the canopy volume. So that, the regional heat capacity in 1994 amounted 19384 MJ °C−1 increased to 19929 MJ°C−1 in 2000. Data observation for 2000-2010 showed that forest area decreased by 66% due to forest’s clearing into oil palm plantations (47%), shrubs (8%) and bare soil (11%). However, plant’s biomass continues to increased, i.e. 1.48 ton/ha for the forest, 2.73 tons/ha for shrubs and 4.63 tons/ha for bare soil. Before 2000, there was no land cover by oil palm plantations, so the increasing rate from this land was the biggest than the three other lands, amounting to 122.29 tons/ha. Decreasing in the percentage of forest area does not cause a decrease in the heat capacity of the region. Intensive maintenance on oil palm plantation such as water management, fertilizer, and planting space made it biomass productivity, and ability to save the heat is greater than the forest. As a result, in 2010 regional heat capacity increased to 22508 MJ °C−1.
Impact of oil palm plantation on mammal and herpetofauna species diversity
Authors: Santosa Yanto , Rejeki Sani Sari Sri
Published: October 2019

Since 2008, Indonesia has succeeded in becoming the largest palm oil producer in the world. However, this success has drawn some accusations that oil palm plantations come causing deforestation and decreasing biodiversity. The research has been carried out in the topic of "the origin of the status and type of land cover and variations in the wildlife species diversity in oil palm plantations” in Province of Riau, South Sumatra, Central Kalimantan and West Kalimantan. The results of the interpretation of Landsat imagery coverage of 1 year before being oil palm plantation and interviews with resource persons showed that the type of land cover of the 8 study locations was 5 in the form of secondary forest, 2 bushes and the rest in the form of rubber plantations. The status of the land as a whole APL or customary land. Furthermore, the results of the comparison of the number and composition of species of mammals and herpetofauna before and after being oil palm plantations show that the impact of oil palm plantations on these two variables of diversity species according to the origin of land cover types. For the origin of the type of land cover in the form of shrubs or rubber plantations, the impact of oil palm plantations is positive because it increases the number of species both mammals and herpetofauna (except the number of species of herpetofauna on KJNP estate plantations). As for the origin of the type of land cover in the form of secondary forest, the existence of oil palm plantations increase the number of mamalia in 2 locations and herpetofauna in 4 locations The presence of oil palm plantations is thought to have caused changes in the composition of species with a range of 50 to 100% for mammals and 23 to 76% for herpetofauna.
Does oil palm plantation establishment cause loss/gain of bird species? (Case study: KGP oil palm plantation, West Kalimantan)
Authors: Karuniyanti Diah Eres Dwi , Santosa Yanto
Published: October 2019

Oil palm plantation expansion in Indonesia always been associated as the cause of deforestation and loss of biodiversity. This research was conducted aiming to verify that allegation. The study was conducted from July to August 2018 and carried out in an independent oil palm plantation company, KGP in West Kalimantan. To identify the loss and gain of the bird species, an observation about the bird diversity was conducted. Five transects were laid out in each land covers (4 in the oil palm plantation and 1 in the shrub [baseline]). The analysis showed that the bird species found in the shrub was slightly smaller (22 species) then the species found in the oil palm plantation land covers (27 species). A total of 3 species were found only in shrubland cover which later is assumed as the loss. On the other side, 18 species were only found in the oil palm plantation assumed as a gain. These could be happening as 60% of the bird species composition found in shrub were almost the same as those in the High Conservation Value (HCV) land covers which belong to oil palm plantation land cover. Hence, the existence of oil palm plantation did cause a loss to the bird species but also happen to gain some other new species.
Loss and gain of the bird species after the establishment of oil palm plantation in South Sumatra
Authors: Erniwati  , Santosa Yanto
Published: October 2019

The development of oil palm has been documented as one of factor caused deforestation leading to the loss of biodiversity, however, to what extent the impacts of oil palm conversion on biodiversity in South Sumatra remain little-known. To answer this issue, we studied the diversity of bird in the area before and after oil palm established by calculating species number, richness, evenness, similarity, and composition. Secondary forest, shrubs and rubber plantation were identified as area before oil palm establishment through Landsat image analysis, while in the established oil palm plantation area, we classified into the young, mature and old stand of oil palm. We recorded 49 bird species, 25 families and 298 individuals. Our result showed that conversion secondary forest, shrubs and rubber plantation to oil palm plantation resulted in the variation of losing, gaining, and persisting of bird species at both habitats. Losses of bird species varied about 16%-38%, but the loss of bird species was more drastic in shrubs. Gaining of bird species also varied about 12.5% to 45% where conversion rubber plantation to oil palm impacted the highest bird species procuration. Meanwhile, bird species persistence ranged between 38%-50%. Secondary forest as the habitat condition before the establishment of oil palm had the highest bird diversity (33 species), while the palm oil plantations had the lowest bird species (11 species). The most of bird species lost were insectivorous birds. However, bird species gain was also dominated by insectivorous birds. Declines in insectivorous bird species that are important for an ecosystem process service in this study area may not significantly decline in that process service because of the other species in the similar functionally group increase in the response. Calculation of loss and gain of biodiversity as a result of land use change is necessary as a strategy for biodiversity conservation in an agricultural landscape.
Impact of oil palm plantations on herpetofauna species diversity in KGP and CNG, West Kalimantan
Authors: Rahmadiyanti Putri , Santosa Yanto
Published: October 2019

Palm oil (Elaeis guineensis Jacq) is one of the fastest growing in the tropics so that the development of oil palm plantation is the one threats of the decrease of biodiversity including herpetofauna. That is why this research becomes important to study the impact of oil palm plantation on diversity and composition of herpetofauna. This research was conducted in July 2018 in Ketapang District, West Kalimantan Province in two oil palm plantation companies (KGP and CNG). Data collecting were using Visual Encounter Survey (VES) method combined with Strip Transect Method, in five lands covers (young-aged, middle-aged, old-aged oil palm plantation, high conservation value, and shrubs area) taken simultaneously with three repetitions. The results of this study showed that the establishment of oil palm plantations has impacted species diversity and species composition of herpetofauna. This research showed that the species number of herpetofauna in oil palm plantations is higher than the baseline area. The result of this study also showed that the species diversity and richness of herpetofauna in the high conservation value area is higher compared to another land cover. However, the overall results showed that oil palm plantation has positive impacts to increased and loss of herpetofauna species, there are losing one species and gaining seven species in CNG oil palm plantation, and losing two species and gaining fifteen species in KGP oil palm plantation.
Track Me & Unlock: Secured Mutual Authentication System of Integrating Phone Unlock & Women’s Safety Application using MEMS
Authors: Vengaten S. , Wilferd Roshan M. , Prince Mary S. , Usha Nandini D.
Published: October 2019

In the Existing System, Mobile must be unlocked before using. The widely usage of unlocking types are PIN, password and graph. In the Proposed System, we propose a novel token-based mobile device unlocking approach: transferring the authentication state between two devices by briefly shaking them conjointly. In this system; we propose 4 attributes for phone unlocking. 1. Hand waving pattern in mobile, 2. Creating information from embedded hardware through Bluetooth, 3. MEMS waving pattern by the hardware device, 4.Synchronization of both the device. The unlocking pattern of the mobile will be changing every time for safety reasons, It will be changing randomly. The major advantage of this system, even if hacker knows one of the above specified unlocking password, he have to provide answer based on the required pattern so this is more secured application. We also implement Women’s Safety application along with this implementation. We include two patterns for this application. Pressing the switches in the hardware or Phone’s waving pattern is matched immediately system will understand that Women safety application is initiated. GPS is initiated to save the women by sending location info both to the Guardian and Police.
Secured User Behaviour Based Access Framework for Web Service
Authors: Joseph Manoj R. , Anto Praveena M.D. , Anvesh Manchikalapudi , Pujith Murarisetty
Published: October 2019

There are many web applications around us providing their services using web services. In order to prevent malicious users from accessing the web services is an important challenge now. Hence this proposed access control model provides the user an effective way to prevent the malicious user by calculating the trust value of every user based on their behaviours such as success rate, failure rate, frequent of access, transaction timeout etc., in the web application. This model also notices and precludes IP address spoofing, SQL injection to allow only the authorized users and access appropriate information. Prototype implementation and simulation results show the proposed model is the effective one when it is compared with existing models.
Design and Development of Sensor Based Intelligent Auto Irrigation System
Authors: Asha P. , Ambati Anusha , Anuhya R.
Published: October 2019

The quick improvement and scaling down of sensor gadgets, current advances sensor innovations, are enabling researchers and specialists to grow little sensors that can be utilized to ceaselessly screen the wellbeing and steadiness of the Plants Environment.Sensors with figuring, handling and correspondence abilities that can persistently detect and Triggers Solenoid esteem, where naturally can be prepared and seen progressively. This venture gives a nitty gritty investigation and usage of a sensor for checking of Green House parameters like moistness, water levels, etc.… A Sensor network was implemented using an Aurdino based AVR the microcontroller.
Review on Non Invasive Glucose and Cholesterol Measurement System
Authors: Joseph Devakumar V. , Ravi T. , Karthikeyan S.
Published: October 2019

Diabetes and Cholesterol has become a common disease all over the world. Continuous monitoring of the glucose and cholesterol levels is needed in case of physically disabled and unconscious people where it is hectic to take measurements invasively or through blood samples. The proposed model brings out an idea of measuring glucose and cholesterol levels without the need of blood samples or involving contact. This is done with the help of simple IR sensors and Arduino UNO. The patient’s fingers are placed on the IR sensor and power LED sockets with one involving in the measurement of cholesterol and other in measurement of glucose. For the diabetic patients and pregnant ladies have to monitor the glucose and cholesterol level frequency. The minimum level of cholesterol in blood is causes to the cardiovascular disease, that leads to stoke and heart attack. Based on the reflection of power LED light through the blood cells, the values are fed to the Arduino UNO. With the help of program dumped in the Arduino UNO, glucose and cholesterol values are calculated. In addition to that Hemoglobin and also LDL and HDL values are also calculated which is a further advantage. The proposed model costs less and saves more time. Further advancements can be done by employing this project by using IoT which can feed the measured data online. Non invasive measurement methodology of measuring glucose and cholesterol is not implemented anywhere which describes the uniqueness and innovation involved in this method. The model is not affected by external interrupts such as external sources of light etc and works efficiently under every conditions.
Wireless Power Transmission
Authors: Bhavya Keerthi V. , Swetha V. , Annadevi E.
Published: October 2019

In recent days, Wireless Power Transfer (WPT) and harvesting energy received lots of attentions due to the necessity of having a flexible, suitable and secure source of energy. With the explosion of wireless technologies including wireless sensor network (WSN) like internet of things, such intelligent systems had highlighted this need. Wireless power transfer is a key technology to enable any device operation without replacing their batteries, often challenging due to cost of replacement and the difficulty to reach inaccessible areas. Anyhow wireless power transfer is being considered as eco-friendly. This also removes the need to dispose dead batteries. Inductive coupling can be used to charge the low power devices quickly and effectively without the help of wires. This method is done by using charging a resonant coil from AC and then transmitting subsequent power to the resistive load. In this case, oscillating circuit is used in the conversion of DC to AC in order to transmit the magnetic field by passing frequency and inducing the receiver coil. The system is designed and constructed as two parts. They are Transmitter part and Receiver part. To calculate the inductive coupling between the transmitter oil and receiver coil, Ampere’s Law, Biot-Savart’s Law and Faraday’s Law are used as per the requirement.
Weather Prediction Using Multi Linear Regression Algorithm
Authors: Anusha N , Sai Chaithanya M , Jithendranath Reddy Guru
Published: October 2019

Weather forecasting is one of the applications of science and technology, used to predict the weather condition depending on the input attributes. Most of the existing systems are implemented using statistical approaches for Support Vector Machine (SVM), which are incapable of giving the accurate prediction as they cannot capture sudden changes in weather conditions. The proposed technique uses the concept of Multi-Linear regression which can produce better results than existing methods.
A Survey Paper on Colour Detection System for Industrial Applications Using Arduino
Authors: Baron Sam B. , Ekka Abhilash , Ashfaq Hingora M.
Published: October 2019

A Colour Sensor, as the name recommends, is a gadget that faculties or recognizes hues. A shading sensor makes utilization of an outer wellspring of discharging light (a variety of four light transmitting diodes to be exact) and afterward breaks down the light reflected over from the protest with a specific end goal to decide the question’s shading. Shading sensors will give a precise shade of the question. An extensive variety of uses can be done utilizing shading sensors like arranging of items in light of their shading, quality evaluation frameworks, shading improvement in printers and so on. In this project, we intend to design an Arduino Colour Sensing and detection application, which has the capability to detect distinct colours. We have utilized TCS3200 shading sensors for this reason. Prologue to shading sensor, circuit chart and working of the Arduino Colour Sensor venture are clarified further.
Design and Fabrication of Micro Strip Antenna for Cubesat Applications
Authors: Tharun K , Vivekanand V , Ravi T. , Sugadev M.
Published: October 2019

In this work we have designed an antenna for 450 MHz in UHF band using rectangular micro-strip patch antenna. It is used for most complex multi band characteristics. Micro-strip antenna has two elementary systems for cubesat. Micro-strip antenna consists of conducting patch on a ground plane separated by dielectric substrate radiation from ground plane has different dielectric configurations. Two antennas are including slot and micro-strip patch antenna. Slot antennas can be placed around solar cells and the slots are narrow enough to be fit into the space between solar cells. Launching the large conventional satellite takes more time and expensive to design the satellite. Cubesats has been proposed to serve the purpose in satellite application cubesat has no more than 1.33kg/unit which reduces the size of satellite and make it less expensive. The proposed antenna at 450Mhz in UHF band and we have achieved 4.2771 of average of gain with parameters of 60*60*1.6mm.
Cut Node Recovery Protocol for Wireless Sensor Network
Authors: Anna Devi E. , Martin Leo Manickam J.
Published: October 2019

In wireless sensor network (WSN), energy efficiency and network lifetime are the important attributes to be improved for enhancing the performance of the network. Due to the failure or cut of a node, performance of the network is affected. So cut node detection and recovery are presented in this paper. Initially, sensor nodes in the search area are clustered using the node weight of the sensor nodes. The node with maximum weight is selected as cluster head (CH) and this CH performs as a monitor node which monitors all non-CH members in a cluster. Backup nodes (BNs) are selected in each cluster using Particle Swarm Optimization (PSO) algorithm. Cut node in the network is detected based on its hop-count and link cost value. This cut node is recovered by the selected backup nodes and mobile nodes (MNs) in the network. Simulation results show that the performance of the proposed approach outperforms that of the existing approach in terms of overhead, energy efficiency, network lifetime and BN selection time.
Quantitative assessment of interfacial condition of cold joint using surface wave group velocity profile
Authors: Lin Y-C , Cheng C-C , Chiang C-H , Hsu K-T
Published: October 2019

Improperly constructed cold joints lead to poor water tightness. Water, chloride ions, and other harmful substances can therefore enter through the joint, causing the accelerated corrosion of steel bars. In this study, the surface wave group velocity profile, which can identify velocity at variant depths beneath concrete surfaces, was used to determine the interfacial condition of a cold joint. The proposed test method performed a single test with one impacting source and one receiver placed on a concrete surface across the joint. The short-time Fourier transform (STFT) and the reassignment technique were used to process the received signal and obtain the image of the group velocity spectrogram. The surface wave group velocity profile was then extracted from the spectrogram. A 0.4 m-thick reinforced concrete wall containing a cold joint was constructed for the experimental studies. The experimental results revealed a sudden decrease in wave speed for wavelengths larger than 0.2 m: the Rayleigh wave speed dropped from 2,000 m/s for normal concrete to 1,300 m/s for concrete including a cold joint. These results suggest that the rebars near both sides of the wall surface constrained the joint from separating up to the depth of 0.1 m; however, a poor interfacial condition was found near the center of the wall.
Study on the optimum nano-natural pozzolan content in the concrete binder
Authors: al-Swaidani A M , Meziab A
Published: October 2019

The objective of this study is to investigate the optimum nano-natural pozzolan (NNP) content in the NNP-based binder concrete. NNP was obtained by grinding a local volcanic scoria for six hours. Twenty-four concrete mixes with four w/b ratios (0.4, 0.5, 0.6 and 0.7) and six-replacement levels of NNP (0%, 1%, 2%, 3%, 4%, and 5%) have been produced. The investigated concrete properties were the compressive strength, the water penetration depth, the concrete porosity and the chloride ion permeability. The efficiency factor (k) of NNP in terms of compressive strength was calculated using the Bolomey equation. Durability indicators have been used to globally evaluate the behavior of NNP-based binder concrete versus control concrete. The results revealed that the efficiency factor (k) decreased to some extent when the NNP content was more than 4%. The calculated durability indicators showed that NNP contents of 3-4% had approximately the highest indicators values. These indicators would be helpful for concrete mix designers. Some correlations between the investigated properties were derived from the analyzed data. The modification of the microstructure of NNP-based cement paste has been observed, as well.
A framework for ethical procurement of construction projects in Nigerian Federal Universities
Authors: Abdullahi N Z , Gambo N , Mohammad S A
Published: October 2019

Procurement of construction projects in Nigerian Federal Universities has been affected by unethical procurement practices amongst the stakeholders and projects parties concern. This study aims at developing a framework to mediating the large negative effects of unethical procurement practices on construction projects development. Conflict of interest factors, especially at the tender and bid evaluation stages, were identified as the major unethical practices affecting construction procurement processes of infrastructure projects negatively. Data were collected using a survey questionnaire distributed to construction procurement stakeholders of nine randomly selected Nigerian Federal Universities. Mediation effect of ethical procurement practices was tested between the conflict of interest factors and procurement of construction and infrastructural projects. The findings revealed that conflict of interest factors were found to have large negative effects on procurement of construction and infrastructural project, and ethical procurement practices identified and introduced as mediating variables were tested and verified to possibly mitigate the effects of conflict of interest factors affecting the procurement of construction and infrastructural projects in Nigerian federal universities. Hence, the study recommends that procurement entities concern should ensure compliance with Public Procurement Guidelines (PPGs), which highlights ethical requirements for tendering, bid evaluation and construction processes for the procurement of construction and infrastructural projects.
Influence of material spatial variability on slope stability in soft rock
Authors: Hsu S C , Hsieh T P , Tsai P H
Published: October 2019

Impacts of material spatial variability usually are not considered in traditional slope stability analyses. However, most geotechnical materials are not uniform inside a slope. The objective of the present study was to evaluate the impact of material spatial variability on slopes in soft rocks. The random field model was used to obtain the material spatial variability. The numerical analyses of slopes in soft rock mass were performed using a distinct element method based program UDEC. After that, Monte Carlo simulation, UDEC, and random field models were used together to analyze the impact of material variability and the slope stability. A series of numerical experiments were performed to understand the effect of joint spacing, joint angle, and size of scale fluctuation (δ). Also, failure types and mechanisms were synthesized and evaluated. The probability of failure became higher as the slope considered horizontal spatial variability of the material. The influence of the horizontal size of δ on slopes without joints was much higher than the slopes with joints. In addition, the slopes with joints yielded fewer failures as δ increased. The results of the analyses could be used for prevention of slope failure, future support system, and geotechnical exploration.
Pressurized clay injection method using kaolinite for controlling groundwater of a saturated sand layer
Authors: Komatsu M , Takahashi K , Takimoto K
Published: October 2019

In tunnel construction in the city area, NATM method is adopted for construction by the limitation of the construction condition. When classifies roughly in supporting method of construction, there are against the spring water, face stability, ground surface subsidence, cement, water glass and urethane are usually used for grouting material against the spring water, but there is the concern, such as expensive and high load on the environment because of artificial materials. On the other hand, Kaolinite is a natural material, there is less load on the environment, and many merits in the processing of the excavated muck. Therefore, we focused a pressurized clay injection method by using the above-mentioned characteristics and applied this to the construction of the underground. In this paper, the availability of the injection a fluid with a dispersion of kaolinite was discussed to summarize the applicability for controlling groundwater of the saturated sand layer. Specifically, a one-dimensional column test was conducted under the high hydraulic gradient. As a result, it was shown the possibility of effecting of decreasing hydraulic conductivity at less than one-order. Consequently, it is concluded hydraulic conductivity of sand layer was able to be reduced by Kaoline clay suspension.
The potential of using performance information in the assessment of existing quay walls
Authors: den Adel N , de Gijt J G , Wolters H J , Schweckendiek T
Published: October 2019

The design of new and assessment of existing quay walls is subject to large uncertainties. Dealing with these uncertainties is a crucial part of the engineering process. The way uncertainties are addressed has a large impact on construction and maintenance costs and on the reliability ultimately obtained. Especially in the assessment of existing structures the uncertainties can be large. An existing structure allows us to use actual performance information in the assessment, such as the structural response to loading. One way to obtain the structural response is test loading assisted by monitoring. In this research Bayesian updating is used to reduce uncertainties and to more effectively use the obtained measurement data. We present a case study of an existing quay structure along with fictitious measurement data to demonstrate the potential effects of test loading on the reliability of the structure. The results show that Bayesian updating successfully reduces the uncertainty (i.e. standard deviation) of the model prediction. Using monitoring data and Bayesian updating provides a more realistic model of the capacity of the existing quay structure and thus a more accurate reliability assessment. Which may lead to extension of the structure’s lifetime or that higher loads can be accepted.
Some learning cases in the Port of Rotterdam
Authors: de Gijt J G , Brassinga H E , Roubos A A
Published: October 2019

This paper present several cases in the Port of Rotterdam where both in the design and construction phase several different did not marched as expected. These cases are interesting for both the design as well the construction phase of a project. People will make mistakes however the mistakes describes in this paper have to be judged in time as not always everything was understood during the design and construction and the people of that time still these huge structures.
Constructing uncertainty budget for a two-dimensional hydraulic model
Authors: Ozbey N , Gül U S
Published: October 2019

In this study the combined uncertainty of a two-dimensional (2D) hydraulic model expanded at 95% confidence level is estimated and the uncertainty budget for the model outputs is attempted to be constructed. It has been shown that many uncertainty sources in the inputs as well as the procedure applied have a significant impact on the accuracy of two-dimensional hydraulic modelling: the uncertainties in the model inputs due to variations in Manning’s ‘n’ Coefficient assigned, the bridge modelling methods, the equation sets; Diffusion Wave and Full Momentum Equations employed and the geometric data sets for the same river system in the Black Sea Region of Turkey are assessed. To estimate an appropriate M‘n’C and other model inputs of model for a river system with a wide 2D flow area is a daunting task. Therefore, any attempt to quantify uncertainties in the assigned values must be based on the samples large enough to obtain statistically significant results. To achieve this task, Monte Carlo Method is utilized to estimate the contribution of the likely variations of model inputs onto ‘the combined expended uncertainty at 95% confidence level in two-dimensional hydraulic modelling’.
Parametric study of factors influencing the thermal distribution and load-bearing capacity of bonded anchors directly exposed to fire
Authors: Al-Mansouri O , Mege R , Pinoteau N , Lahouar M A , Guillet T , Rémond S
Published: October 2019

Pull-out has been proved to occur more often for bonded anchors under tensile loads at high temperatures than at ambient temperature. The existing evaluation method of bonded anchors under fire only covers steel failure mode. Due to the absence of guidelines for evaluating the pull-out of bonded anchors directly exposed to fire, only the evaluation method for mechanical anchors (without resin) is applicable. This paper presents an experimental study on the influence of different parameters linked to the existing evaluation method by means of pull-out fire tests. Additional unloaded fire investigation tests were conducted to compare different configurations of pull-out fire tests. This paper highlights the level of accuracy of load prediction using the resistance integration method based on temperature profiles of bonded anchors directly exposed to a standard ISO 834 fire. Results showed that parameters such as the existence of metallic fixtures on the rod barely influence the predicted load-bearing capacity and failure time. However, parameters such as adopting concrete element temperature along the thickness instead of steel temperature along the embedment depth, and the existence of insulation around the fixture have a greater influence and may result in a false estimation of the load-bearing capacity and failure time.
Determining fragility of urban low-to-mid rise masonry infilled building
Authors: Sangadji S , Kritiawan S A , Prastiwi S I
Published: October 2019

In seismic analysis of building, infill wall is usually modelled as non-structural elements and, hence, are not taken into account in analytical models. In general, engineers and scientists model these widely used structural system of masonry infilled reinforced concrete frame by considering the infill wall as load applied to the open confining frame. The presence of masonry infills, however, may significantly alter both the stiffness and the strength of the overall structural frame system. This present study aims to evaluate seismic performance of this type of building by developing fragility functions of the structure. Masonry wall was modelled as diagonal strut within the concrete frame. The masonry constituents and its composite properties were determined for the model. Then, the structure was subjected to incremental static lateral loading while adaptive pushover analysis was utilized to predict the response of the structure. As the damage states were defined from the spectral capacity curves, the fragility functions were developed for the structure. Effect of masonry wall included in the analysis was then compared to the results of open frame. The result of the eigen value analysis shows, the period for modelling a structure with an infill wall is smaller compared to modelling a structure without infill wall (open frame). This shows that the existence of infill wall elements in modelling increases the value of structural stiffness so that it reduces the period of the structure. Whereas, the results of the fragility curve in both structural modelling show that at some level of damage, the probability of damage for modelling structures with infill walls is smaller when compared to open frame. Realistic and rational results is presented in this work which show that modelling masonry wall with compression strut is beneficial.
Truss structure optimization for two design variable elements using Genetic Algorithm with stress and failure probability constraints
Authors: Kurniawan Mahadi , Adha Augusta
Published: October 2019

This paper presents the results of a study on trusses which are need to satisfy optimal conditions, i.e. the lowest Cost possible cost with maximal performance. The trusses considered were statically indeterminate steel structures with a multi-system loading. The cost is represented by the material volume of the structure and the maximal performance is reflected by the high working stresses reflect the maximum performance within allowable stress limits. The material strength was modeled as a random variable with a Log Normal distribution. The structures are also required to meet a failure probability of Pf =10-3, which may occur locally within the elements as well as globally on the structure as a whole. The complexity of optimization problems depends in general on the number of the considered variables. The larger the number of variables considered, the more complicated becomes the solution process. Therefore, cases of single variable elements such as multi variables ones were considered in this study. Optimization problems are usually solved by applying iterative procedures, frequently resorting to mathematical programming. In these procedures the process usually converges to unreliable solutions; it even may completely bogged down with no solution. To circumvent this problem, iteration was carried out by applying Genetic Algorithms where the process proceeds in a stochastic manner.
Flexural performance of full and partially steel fibre reinforced self-compacting concrete (SCFRC) ribbed slab
Authors: Ahmad H , Hashim M H M , Bakar A A , Rahman F A
Published: October 2019

This paper studies the influence of steel fibre distribution and the flange thickness on the flexural behaviour of steel fibre reinforced self-compacting concrete (SCFRC) ribbed slab. Six (6) ribbed slab panels that were fully and partially reinforced with steel fibres with the dimension of 2.8 x 1.2 m were fabricated for the purpose of this study. Variations were also made in terms of the flange thicknesses, i.e. 80, 100 and 120 mm. All slab panels were loaded under four-point bending. Hooked end steel fibres were incorporated in the mix with the volume fraction of 1% (80 kg/m3). The ultimate load of the fully reinforced panels showed 15-52% higher values than partially reinforced panels. The highest difference was exhibited by the sample with 120 mm flange thickness. Significant difference was observed in the fully reinforced samples, with the 120 mm sample showing the highest ultimate load. The influence was however less imminent as for the partially reinforced sample. The load-deflection curves for the SFWS panel showed smooth deflection hardening curve while SFT samples exhibited steeper curves. As a whole, it can be concluded that better performance was demonstrated by the fully reinforced sample with the highest flange thickness.
Structural reliability of RC elements with electric arc furnace slag as recycled aggregates
Authors: Zanini M A , De Stefani E , Faleschini F , Pellegrino C
Published: October 2019

Sustainable development issues have become very important in the recent years, and the increased sensibility on sustainability of civil engineering structures are inducing to set the attention in recycling operations, also in the context of building materials. Concrete is the most used construction material in the world and its production requires a considerable demand of energy and raw materials, inducing significant gases emissions and huge quantity of natural materials and non-renewable resources exploitation. Electric Arc Furnace Concrete (EAF concrete) is a kind of recycled concrete in which its aggregates are the by-product of steel and iron producing processes, the so called Electric Arc Furnace (EAF) slag: while its environmental positive effect is easily understandable and intuitive, its effective usefulness and reliability in the building field is more difficult to accept. From the literature data, it seems that EAF concrete presents higher values of compressive and tensile strengths and modulus of elasticity than the natural concrete ones, and this might induces one to think that a higher structural reliability could be expected. However, it is worth recalling that this material is characterized by also a higher self-weight, thus, increasing the dead-load values. Hence, in this study, a reliability-based analysis of the structural load-carrying capacity of EAF reinforced concrete (RC) elements is carried out, through a fully probabilistic approach based on Monte Carlo simulations improved by Latin Hypercube method (LHS). The analysed RC elements are designed according to the Italian current construction code, and then, considering all the uncertainties included in the random variables definition, failure probability and relative reliability index are estimated and compared to the reliability of the same RC elements with natural concrete. Results indicate that, for the analysed cases, when EAF slag is used as coarse recycled aggregate, it is possible to guarantee the same reliability level than in RC elements realised with natural concrete.
Influence of concrete humidity on the temperature development under fatigue compressive loading
Authors: Markert M , Birtel V , Garrecht H
Published: October 2019

Due to research activities on the topic of concrete mixtures during the last decades concrete compressive strength could be increased significantly. At the same time the lifespan of concrete structures has been continuously extended. Therefore, the fatigue behavior of modern High Performance Concrete (HPC) becomes more important with respect to service life. Previous studies on normal strength concrete have shown that the number of cycles to failure under pure compressive cyclic loading mainly depends on frequency and amplitude. An increase of the loading frequency leads to a higher number of load cycles to failure. Recent research work shows that the humidity of the specimen is also influencing the fatigue behavior of concrete. Conditioning of the test specimen to high humidity led to significant lower fatigue life. Other research activities on high strength concrete point out the effect of the loading frequency on load induced heat effects of the concrete. The experimental study presented here aims on the influence of the humidity on the temperature development under fatigue compressive loading and on the number of cycles to failure. It comprises three fatigue test series at a test frequency of 10 Hz with sealed cylindrical specimens of the same concrete with different degrees of humidity. In addition, destructive and non-destructive tests were carried out on damaged and undamaged concrete.
Low heat concrete hydration thermal reduction with bioconc
Authors: Basoeki M , Koespiadi  , Ekaputri J J
Published: October 2019

This paper presents the experimental study on the control of the heat of hydration of mass concrete using the concrete bio-admixture, bioconc. The basic issue of mass concrete is thermal cracking, because of the heat of hydration of the cement content in mass concrete. This paper reports on the research results of using the concrete bio admixture, bioconc as a micro filler. To control the heat of hydration of mass concrete the cement content was reduced significantly up to 40 percent. The product is called bioconc low heat concrete. In order to control the researched object, it was compared with: pre-coolingmasscon and fly ash based low heat masscon. There were three parameters to be compared for asessing the product: hydration heat control effectiveness, cost of raw materials and the environmental impact. In this research, the concrete was made with fc’ 25 and the size of the mass concrete mock-up was 1000x1000x2500 mm3. Research result written in series of following data: the peak temperature, duration to reach peak temperature, thermal gap between core-edge off masscon and masscon raw material cost. The peak temperature at bioconc low heat concrete was 63.5 °C within 29.5 hours after pouring. It has thermal different at 19.5 °C. The cost of material was US$ 54.6 per cubic meter.
Characteristics of geopolymer hybrid concrete in peat water
Authors: Wijaya M F , Olivia M , Wibisono G , Saputra E , Wang S
Published: October 2019

Geopolymer hybrid is a combination of geopolymer and Ordinary Portland Cement (OPC) or other binders to produce an alternative binder. This type of binder could be used to transform low-quality fly ash into multi-purpose concrete. Ordinary Portland Cement (OPC) concrete subjected to an acidic organic environment such as peatland, is more prone to deterioration in long-term than concrete using the supplementary cementitious material. In this research, the geopolymer was made by activating low-quality fly ash (contains more than 5% carbon) with the alkaline activator. The inclusion of OPC and Portland Cement Composite (PCC) as a fly ash replacement material is intended to promote curing at ambient temperature and immobilization of heavy metals in fly ash. The specimens were cast and cured at ambient temperature up to 28 days. OPC was used as a control mix. Subsequently, the concrete was immersed in fresh peat water in the laboratory up to 28 days. Characteristics of the geopolymer hybrid such as compressive strength, porosity, and leaching were determined. Microstructure analysis, such as SEM-EDX and FTIR, were conducted. Results show that the geopolymer hybrid has a good strength development at early days. At 28 days, there was a reduction of strength and increase of porosity, probably due to the attack of calcium from the OPC concrete. There was a transformation of aluminosilicate gel into C/N-A-S-H that is advantageous for the strength development at the early days. However, a weaker material has formed in the long term that cannot resist further acid attack. It can be concluded that the geopolymer hybrid is a promising binder, but it is essential to design the material appropriately to have better strength, durability and environmental properties in the long term.
Resilient modulus values of Western Australia asphalt pavement
Authors: Wibisono G , Nikraz H R
Published: October 2019

Resilient modulus (MR) is a property to measure the material’s stiffness in designing asphalt pavement thickness. The value is usually calculated from an Indirect Tensile Test (ITT) for decades since it is considered efficient and more practical in most applications, and it only uses a single loading time and temperature. The Austroads 2008 still included the resilient modulus values from ITT as an input value at the initial pavement design stage due to its practicality in the application, although this conventional approach has no longer been used in a mechanistic-empirical design guide by NCHRP. In this research, three asphalt mixtures with variables of aggregates diameter and type of asphalt using Western Australia materials were investigated. The mixes, i.e. AC10-320, AC14-320, and AC20-320, were cast in cylinders with a dimension of 75×100mm at a reference temperature of 25°C. The indirect tensile strength used triplicate samples. Research shows the resilient modulus values increase with an increase of nominal maximum aggregate size and a decrease of air voids percentage. The highest MR values were given by mix AC-320 with 3% air voids compared to other mixtures variation. The reasons are an improvement in particle-to-particle contact between the aggregates and density with low air voids in the mixes. From this study, the resilient modulus values of Western Australian asphalt mixtures still meet the lower part of the range of the Austroads presumptive values and recommend as indicative values for design input in pavement thickness calculation.
Determining stiffness modulus by means of different mechanical testing
Authors: Pramesti F P , Poot M R , Van de Ven M F C , Molenaar A A A
Published: October 2019

Many research on mechanistic testing have come to likely conclusion that different test setup results in different performance. The aim of this paper is to analyse the stiffness modulus resulting from three different test setups, namely; Monotonic Uniaxial Tension Test (MUTT), Monotonic Uniaxial Compression Test (MUCT), and Indirect Tensile Test (ITT). They are monotonic tests. This paper will elaborate if there is any significant difference among the result of the first three tests. Master curves of stiffness modulus as a function of strain rate at reference temperature of 15°C were developed. The results show that there is no significance difference between the modulus resulting from the three tests performed at high strain rates. It’s also shown that at low strain rate, the elastic modulus resulting from compression tests is in between indirect and uniaxial tension test’s elastic modulus.