Civil Engineering Dimension (E-Journal)
Not a member yet
443 research outputs found
Sort by
Comprehensive Investigation on the Potential of Fly Ash from New Source as Construction Material
Full text linkFly ash has been highly advocated to be re-utilized as a construction material. The most common utilization is to partially replace cement in a low-percentage scheme. However, there are several other schemes available to potentially use fly ash as binder in concrete that have not been widely exercised, especially those utilizing it in high to very high volume. In those schemes, high-volume fly ash (HVFA) concrete might use more than 50% fly ash to replace cement. To exploit its self-cementing properties, with or without the addition of other compounds, such as calcium hydroxide, fly ash might be used in very high percentage of cement replacement. In geopolymeric system, fly ash acts as the precursor of a stable binder, with the presence of highly alkaline solution. This paper demonstrates a model to investigate the potential of fly ash in several binder systems. The results show that fly ash from a good source can be utilized as an alternative binder in several different schemes
Performance of a Cold Formed Steel Pedestrian Bridge under Static and Dynamic Loads
Full text linkThis paper summarizes new application of CFS in bridge constructions where a seven meters long pedestrian bridge was constructed. The bridge has 1.2m width, 0.8m depth, and is composed of CFS Warren truss and bondek floor systems. Natural frequency of the bridge considering only dead load application was found as 8.54 Hz and decreased to 7.08 Hz when the live load was included. Under static load test, the application of dead load only and both dead and live loads yielded a maximum deflection of 3.53 and 8.1 mm, respectively. Normal walking and running pedestrian loads were carried out created a maximum acceleration equaled to 0.11g. Lastly, sinusoidal waves application facilitated through a three-phase induction motor having self-weight of 24.86 kgf at frequency equal to 8.5 Hz was performed for one hour resulting no decrease of the natural frequency, thus the bridge can be assumed to experience no noticeable stiffness degradation
Performance of Six- and Ten-story Reinforced Concrete Buildings Designed by using Modified Partial Capacity Design (M-PCD) Method with 70% Shear Force Ratio
Full text linkOne design alternative of earthquake resistant building is Partial Capacity Design (PCD) method. Unlike the commonly used capacity design method, PCD allows a safe failure mechanism which is called partial sidesway mechanism. In this mechanism, all beams and some columns are allowed to experience plastic damages while some selected columns are designed to remain elastic (called elastic columns). A new approach to predict the required strengths needed to design each structural member, called modified-PCD (M-PCD) is proposed. In this research six- and ten-story reinforced concrete buildings were designed using M-PCD, and their seismic performances are investigated. The base shear force resisted by the elastic columns was set to approximately 70% of the total base shear. Both nonlinear static procedure (NSP) and nonlinear dynamic procedure (NDP) are used to analyze the structures. The results show that the expected partial side sway mechanism is observed, and the drifts of the buildings are acceptable
The Utilization of Milk as a Catalyst Material in Enzyme-Mediated Calcite Precipitation (EMCP) for Crack-Healing in Concrete
Full text linkThis study discussed the applicability of the calcite precipitation method to repair the concrete's crack. The grouting solution of Enzyme-Mediated Calcite Precipitation (EMCP) was modified by adding milk as a catalyst in calcite formation. Cracks in concrete samples were made when the concrete was 28 days with a width of 0.1-0.3 mm. The EMCP solution composed of urease, urea, CaCl2, and milk was injected into the cracked concrete sample, and its effect on permeability and compressive strength tests were evaluated. The result shows that the optimum composition of milk used in the formation of calcite had a concentration of 5 g/L with an initial preparation temperature of 70oC, which produced 26% higher than the initial EMCP solution. The mechanical test results show that the reduction of coefficient of permeability of 92.23% compared to the cracked sample and the improve strength up to 98.75% of the non-cracked sample were obtained by three circles injection. This study elucidated that milk utilization as a catalyst material in repairing cracks with the EMCP method is a potential method for crack-healing concrete
Climate Change Impact in Flores Island, a Dry Region in Indonesia
Full text linkClimate change impacts have gained great attention to be studied in various fields. In this paper, an investigation of rainfall pattern change is performed using three statistical methods, i.e., simple linear regression, t-test, and Mann-Kendall’s test. The analysis is performed at 10- and 20-year time scales of daily, monthly, and annual rainfall in Flores Island, a dry region in Indonesia. In general, an increasing monthly rainfall trend is detected in the rainy season (October – April) at a 20-year period, using all three methods. Specifically, a significant increasing trend in March 1989 – 2008 is observed, and it contributes to the significant increasing trend of annual rainfall. The findings presented in this paper should be an alert for potential climate change impacts in the region. The positive consideration of having more rainfall in a dry region might turn into a negative reality when adaptation measures are not well-prepared
Guideline for Survey, Investigation, and Design of Black Spot Location (SID-BSL) and Its Application in Lampung Province, Indonesia
Full text linkIn connection with the government's obligation to take responsibility for ensuring the safety of traffic and road transport for road users, it is necessary to conduct Surveys, Investigations, and Design of Black Spot Location (SID-BSL) to reduce traffic accident. Hence a guideline in conducting SID-BSL is needed. In this study, the author compiled a simple technique of prioritization for SID-BSL procedure and applies it to a research on National Roads in the Lampung Province. The technique of prioritization is simplified with four phase activities namely Preparation, Initial Analysis, Detail Survey, and Detail Analysis. The analysis technique is based on the ranking of Black Spot Locations using weighted accident number (WAN). Application procedure is applied on 237 events of accident on the National Roads in Lampung Province resulting five selected BSLs to be treated according to the availability of funds
Absorption Characteristics of Cement Combination Concrete Containing Portland Cement, fly ash, and Metakaolin
Full text linkThe resistance to water penetration of cement combination concretes containing Portland cement (PC), fly ash (FA), and metakaolin (MK) have been investigated at different water/cement (w/c) ratios, 28-day strengths, and depths of water penetration using their material costs and embodied carbon-dioxide (eCO2) contents. Results revealed that, at equal w/c ratio, eCO2 content reduced with increasing content of FA and MK. MK contributed to the 28-day strengths more than FA. Compared with PC, FA reduced cost and increased the depth of water penetration, MK increased cost and reduced the depth of water penetration, and their ternary combinations become beneficial. At equal strengths and levels of resistance to water penetration, most of the cement combination concretes are more environmentally compatible and costlier than PC concrete. Only MK binary cement concretes with 10%MK content or more and ternary cement concretes at a total replacement level of 55% with 10%MK content or more have higher resistance to water penetration than PC concrete
Predicting the Response of Shear-critical Reinforced Concrete Beams using Response-2000 and SNI 2847:2013
Full text linkThis study investigates the accuracy of Response-2000 in predicting the response of shear-critical reinforced concrete beams. The experimental data selected was that obtained by Vecchio and Shim in 2004 on twelve reinforced concrete beams which sought to replicate beams originally tested by Bresler and Scordelis in the early 1960s. This study also aims to compare the results obtained to the predictions of SNI 2847:2013. It is demonstrated that Response-2000 is capable of providing accurate predictions of load-deflection responses up to the peak load, but underestimates the ductility of beams that exhibit a mixed flexure-shear failure mode. It is also shown that both methods provide conservative predictions of the shear strength of beams with no shear reinforcement, with the software providing more consistent and reliable predictions of shear strength of beams containing shear reinforcement
The Application of Statistical Design of Experiments to Study the In-Plane Shear Behaviour of Hybrid Composite Sandwich Panel
Full text linkThis paper presents a statistical aspect of experimental study on the in-plane shear behaviour of hybrid composite sandwich panel with intermediate layer. The study was aimed at providing information of how significant the contribution of intermediate layer to the in-plane shear behaviour of new developed sandwich panel. The investigation was designed as a single factor experimental design and the results were throughly analysed with statistics software; Minitab 15. The panels were tested by applying a tensile force along the diagonal of the test frame simulating pure shear using a 100 kN MTS servo-hydraulic UTM. The result shows that the incorporation of intermediate layer has sinificantly enhanced the in-plane shear behaviour of hybrid composite sandwich panel. The statistical analysis shows that the value of F0 is much higher than the value of Ftable, which has a meaning that the improvement provided by the incorporation of intermediate layer is statistically significant
Effect of Cement Replacement with Carbide Waste on the Strength of Stabilized Clay Subgrade
Full text linkCement is commonly used for soil stabilization and many other ground improvement techniques. Cement is believed to be very good to improve the compressive and split-tensile strength of clay subgrades. In some application cement could be partly or fully replaced with carbide waste. This research is to study the effectiveness of the cement replacement and to find the maximum carbide waste content to be allowed for a clay subgrade. The quantities of cement replaced with the carbide waste were 30, 50, 70, 90, and 100% by its mass. The results show that replacing the cement with carbide waste decreased both the compressive and split tensile strength. Replacing cement content with carbide waste reduced its ability for stabilization. The carbide waste content should be less than 70% of the cement to provide a sufficient stabilizing effect on a clay subgrade