Effect of Specimen Size on the Tensile Strength Behavior of the Plastic Waste Fiber Reinforced Soil – Lime – Rice Husk Ash Mixtures

Improvement of tensile strength in fiber reinforced soil is an important research topic. A study has been undertaken to investigate the strength of stabilized clay-soil reinforced with randomly distributed discrete plastic waste fibers by carrying out split tensile strength test. In this study, the clay soil was stabilized with lime and rice husk ash mixtures. The main purpose of this research is to investigate the effect of specimen size to the tensile strength behavior. Testing procedure was formulated using extended ASTM C496 standard. The laboratory investigation results showed that split-tensile strength of reinforced specimens increased with increase in size. The limitations of the dataset indicate that specimen size of 70 mm in diameter is the threshold to produce reasonable representative strengths

Lightweight Masonry Block from Oil Palm Kernel Shell

A large amount of waste produced in the processing of palm oil is one of the main contributors to the environmental problem. This paper presents an experimental study on the development of the shellcrete masonry block that made of oil palm kernel. The study was focused on the physical, compressive strength and flexural strength of shellcrete. The eco-efficiency of the shellcrete was also evaluated by measuring the carbon footprint. The shellcrete was made by mixing the Portland cement (PC), sand, and oil palm kernel shell (PKS). A control specimen made of PC and sand mixture (sandcrete) was also prepared. The specimen size was 220 mm length, 110 mm width and 80 mm in thickness. The maximum strength obtained was 22 MPa by mixing proportion of 1 PC:1 Sand:1 PKS, but the recommended mix proportion of the shellcrete for building materials was 1 PC:1 Sand:2 PKS as an optimum mix design for eco-friendly shellcrete

Influence of Rainfall Patterns on the Instability of Slopes

The assessment of rainstorm-induced shallow landslides is still a research topic of wide concern for scientists and engineers. This paper examined the effect of rainfall intensity distribution on shallow landslides. Four synthetic rainfall distributions comprising uniformed, delayed, centralized, and advanced, were selected to examine the effect of rainstorm patterns on slope failure. The infiltration was modeled using Green-Ampt equation, while an infinite slope was selected to model the shallow landslide. Monte Carlo Simulation was applied to analyze the failure probability of the slopes. Two landslide cases were selected to examine the proposed model. The results indicated that among the four representative rainstorm patterns, the advanced rainfall pattern caused worst slope stability. The advanced rainfall pattern resulted in the shortest rainfall duration threshold for landslide occurrence, followed by the central, uniform, and then delayed rainfall pattern. The probabilistic analysis method was suitable to estimate the time of failure for the evaluated landslide cases

Effect of Cement Replacement with Carbide Waste on the Strength of Stabilized Clay Subgrade

Cement 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

Stabilization of residual soil with rice husk ash and cement

Stabilization of residual soils is studied by chemically using cement and rice husk ash. Investigation includes the evaluation of such properties of the soil as compaction, strength, and X-ray diffraction. Test results show that both cement and rice husk ash reduce the plasticity of soils. In term of compactability, addition of rice husk ash and cement decreases the maximum dry density and increases the optimum moisture content. From the viewpoint of plasticity, compaction and strength characteristics, and economy, addition of 6-8 cement and 10-15 rice husk ash is recommended as an optimum amount

Self Compacting Concrete from Uncontrolled Burning of Rice Husk and Blended Fine Aggregate

This paper presents an experimental study on the development of normal strength Self Compacting Concrete (SCC) from uncontrolled burning of Rice Husk Ash (RHA) as a partial replacement to cement and blended fine aggregate whilst maintaining satisfactory properties of SCC. Experiments on the fresh and hardened state properties have been carried out on RHA based SCC from uncontrolled burning. The dosages of RHA are limited to 0%, 20%, 30% & 40% by mass of the total cementitious material in the concrete. The experiments on fresh state properties investigate the filling ability, the passing ability and the segregation resistance of concrete. The experiments on hardened state properties investigate the compressive and the splitting tensile strengths. The water absorption level of the concrete with changing RHA levels has also been monitored. The experimental studies indicate that RHA based SCC developed from uncontrolled burning has a significant potential for use when normal strength is desired

Performance of Masonry Blocks Incorporating Palm Oil Fuel Ash

This paper presents an experimental study on the development of masonry block with Palm Oil Fuel Ash (POFA) as a partial replacement to cement whilst maintaining satisfactory properties of masonry block. The dosages of POFA are limited to 0%, 20%, 40% and 60% by mass of the total cementitious material in the masonry block. The experiments on masonry block investigate the compressive strength and the breaking load for mechanical properties and water absorption and efflorescence for its durability. The compressive strength and the breaking load of the masonry blocks reduce with increasing percentage of POFA replacement. However, it satisfies the requirements of Class 1 and Class 2 load-bearing masonry block according to Malaysian Standard MS76:1972. In terms of durability of the masonry block, water absorption for all the masonry blocks satisfies the requirement of ASTM C55-11 and there is no any sign of efflorescence on all the masonry blocks. POFA based masonry block are also found to be cheaper than the cement sand masonry blocks. The experimental studies indicate that POFA based masonry block has a significant potential for application in the construction industry

Satellite-derived rainfall thresholds for landslide early warning in Bogowonto Catchment, Central Java, Indonesia

Satellite rainfall products for landslide early warning prediction have been spotlighted by several researchers, in the last couple of decades. This study investigates the use of TRMM and ERA-Interim data, for the determination of rainfall thresholds and the prediction of precipitation, respectively, to be used for landslide early warning purposes at the Bogowonto catchment, Central Java, Indonesia. A landslide inventory of 218 landslides for the period of 2003–2016 was compiled, and rainfall data were retrieved for the landslide locations, as given by 6 ground stations, TRMM, and ERA-Interim data. First, rainfall data from the three different sources was compared in terms of correlation and extreme precipitation indices. Second, a procedure for the calculation of rainfall thresholds for landslide occurrence was followed consisting of four steps: i) the TRMM-based rainfall data was reconstructed for selected dates and locations characterized by landslide occurrence and non-occurrence; ii) the antecedent daily rainfall was calculated for 3, 5, 10, 15, 20 and 30 days for the selected dates and locations; iii) two-parameter daily rainfall-antecedent rainfall thresholds were calculated for the aforementioned dates; after analysis of the curves the optimum number of antecedent rainfall days was selected; and (iv) empirical rainfall thresholds for landslide occurrence were determined. The procedure was repeated for the entire landslide dataset, differentiating between forested and built-up areas, and between landslide occurrence in four temporal periods, in relation to the monsoon. The results indicated that TRMM performs well for the detection of very heavy precipitation and can be used to indicate the extreme rainfall events that trigger landslides. On the contrary, as ERA-Interim failed to detect those events, its applicability for LEWS remains limited. The 15-day antecedent rainfall was indicated to mostly affect the landslide occurrence in the area. The rainfall thresholds vary for forested and built-up areas, as well as for the beginning, middle and end of the rainy season