scholarly journals Simulation of Kalirejo Road Side Slope based on Altered Andesite Characters, Kulon Progo Regency, Indonesia

2021 ◽  
Vol 5 (2) ◽  
pp. 101
Author(s):  
Hnin Thandar Phyu ◽  
Heru Hendrayana ◽  
I Gde Budi Indrawan ◽  
Toshitaka Kamai

ABSTRACT. This study is performed to investigate the characteristics of intrusive andesite rock consisting of Kalirejo Road Side Slope located in Kulon Progo Mountains. The rocks consisting the slope are identified by visual observation of hand specimens in the field, petrographic and X-ray Diffraction (XRD) analyses of the rock samples in the laboratory, upon which genetic rock classification is determined. The altered rock types are determined by the presence of specific minerals identified in the petrographic and XRD analyses. The alteration intensity is examined by comparing the amount of secondary minerals to the primary minerals observed in the petrographic and XRD analyses. The developments of rock weathering are determined in the field GSI classification based on the visual characteristics and in the laboratory-based on the Chemical Index of Alteration (CIA) and engineering properties of the altered rocks. The results show that the rocks typically consisted of 33.2 to 59.2% plagioclase, 1.4 to 5.1% quartz, therefore, are classified as andesite. The presence of halloysite, montmorillonite, and kaolinite as secondary minerals in the altered andesite indicated that the parent andesite rocks have undergone argillic alteration. Meanwhile, the percentages of primary minerals to secondary minerals indicate that the andesite rocks have undergone moderate to high alteration intensity. Based on the visual characteristics, the research area consisted of fresh, slight weathered andesite rocks and complete weathered residual soil. The CIA values of the samples are increased with the increase in rock weathering. Identification of visual characteristics of rock weathering appeared to be in good agreement with those classified based on the CIA and engineering properties analysis results. The uniaxial compressive strength (UCS) of rocks and soils is determined by point load tests. Engineering properties of the residual soils are performed by using ASTM standard procedures. In the lower part of the roadside, slope consists of fresh and slightly weathered andesite rocks, which have relatively high strength and are classified as medium strong rocks. Meanwhile, the upper part of the slope profile contained completely weathered residual soil, which had very low compressive strength, are classified as very weak soil.Keywords:  andesite, argillic alteration, Geological Strength Index (GSI), hydrothermal alteration, roadside slope, weathering

2020 ◽  
Vol 5 (1) ◽  
pp. 25
Author(s):  
Heru Hendrayana ◽  
Hnin Thandar Phyu ◽  
I Gde Budi Indrawan ◽  
Toshitaka Kamai

This study was carried out to investigate mineralogical, geochemical, and mechanical characteristics of intrusive igneous rock andesite consisting of Sangon 2 Slope located in Kulon Progo Mountains. Mineralogical characteristics of the rocks consisting of the slope were identified by visual observation of hand specimens in the field and petrographic and X-ray Diffraction (XRD) analyses of the rock samples in the laboratory, which rock genetic classification was determined. Types of rock hydrothermal alterations were determined by the presence of key minerals identified in the petrographic and XRD analyses. Hydrothermal alteration intensity was determined by comparing the number of secondary minerals to the primary minerals observed in the petrographic analyses of thin sections by point counting method. Rock weathering degrees were determined in the field based on the visual characteristics and in the laboratory-based on the Chemical Index of Alteration (CIA) of the rock samples. The rock uniaxial compressive strength (UCS) was determined by point load and compression tests. The results showed that the rocks typically consisted of 6.37 to 74.3% plagioclase, 1.52 to 6.82% quartz, 7.81 to 17.2% hornblende, and 4.81% pyroxene minerals and, therefore, were classified as andesite. The presence of chlorite and calcite as secondary minerals in the andesite rock samples indicated that the parent andesite rocks had undergone prophylactic hydrothermal alteration. Meanwhile, the percentages of primary minerals to secondary minerals indicated that the andesite rocks had undergone weak to high alteration intensity. Based on the visual characteristics, the research area consisted of fresh, slightly, moderately, highly, and completely weathered andesite rocks, and residual soil. The CIA values of the rock samples increased with the increase in rock weathering degree. Rock weathering degrees identified by the visual characteristics appeared to be in good agreement with those classified based on the CIA. The lower part of the mine slope profile consisted of fresh and slightly and moderately weathered andesite rocks, which had relatively high strength and were classified as very strong rocks. Meanwhile, the upper part of the slope profile consisted of highly and completely weathered andesite rocks, which had low compressive strength.Keywords:  andesite, hydrothermal alteration, kulon progo,  prophylactic alteration, weathering


2014 ◽  
Vol 597 ◽  
pp. 345-348 ◽  
Author(s):  
Yeong Nain Sheen ◽  
Li Jeng Huang ◽  
Duc Hien Le

This paper aims to employ combination of residual soil and Class F fly ash in developing a controlled low-strength material (CLSM), primarily used as backfilling material. In the mixture, surplus soil and concrete sand was blended well together with a given proportion of 6:4 by volume. Three levels of binder content (i.e. 80-, 100-and 130 kg/m3) and different percentages fly ash (i.e., 0%, 15%, 30%, and 45%) substituting to Portland cement were previously chosen for mix design. Several major engineering properties of the CLSM such as fresh density, flowability, setting time, water bleeding, unconfined compressive strength, and elastic modulus were investigated via a laboratory study. Testing results indicate that most of the proposed CLSM mixtures satisfy the requirements of excavatability as the 28-days compressive strength ranges from 0.3 to 1.4 MPa. In addition, increase in FA substituting to OPC resulted in workability improvement, setting time extension as well as compressive strength and elastic modulus reduction.


Author(s):  
P .S.K.Murthy ◽  
Sachin Gupta ◽  
Dhirendra Kumar ◽  
Mahabir Dixit

The interconnection of vesicles in basaltic flows greatly affects the engineering properties such as uniaxial compressive strength, modulus of elasticity, Poisson’s ratio, tensile strength and sonic velocities. Sometimes these vesicles are filled with secondary minerals such as quartz/olivine/calcite form as amygdules (which are impermeable). In the present study, to understand effect of porosity, vesicular and amygdular basaltic flows collected from central and west-central India were investigated for these engineering properties and correlated with apparent porosity of core samples. It is observed that a good level of correlation is obtained for uniaxial compressive strength (UCS), elastic modulus (E) and Poisson’s ratio in vesicular basalts when porosity >8-10%. In case of Brazilian strengths a linearly downward trend is observed with the increase in porosity values. And, no significant correlation is observed for waves’ velocities in both variants of basalts.


2018 ◽  
Vol 53 ◽  
pp. 04021
Author(s):  
SHAO Yong ◽  
LIU Xiao-li ◽  
ZHU Jin-jun

Industrial alkali slag is the discharge waste in the process of alkali production. About one million tons of alkali slag is discharged in China in one year. It is a burden on the environment, whether it is directly stacked or discharged into the sea. If we can realize the use of resources, it is a multi-pronged move, so alkali slag is used to improve solidified marine soft soil in this paper. The test results show that the alkali residue can effectively improve the engineering properties of marine soft soil. Among them, the unconfined compressive strength and compressive modulus are increased by about 10 times, and the void ratio and plasticity index can all reach the level of general clay. It shows that alkali slag has the potential to improve marine soft soil and can be popularized in engineering.


2018 ◽  
Vol 8 (8) ◽  
pp. 1324 ◽  
Author(s):  
How-Ji Chen ◽  
Chung-Hao Wu

Expanded shale lightweight aggregates, as the coarse aggregates, were used to produce lightweight aggregate concrete (LWAC) in this research. At the fixed water-cement ratio, paste quantity, and aggregate volume, the effects of various aggregate gradations on the engineering properties of LWAC were investigated. Comparisons to normal-weight concrete (NWC) made under the same conditions were carried out. From the experimental results, using normal weight aggregates that follow the specification requirements (standard gradation) obtained similar NWC compressive strength to that using uniform-sized aggregates. However, the compressive strength of LWAC made using small uniform-sized aggregates was superior to that made from standard-grade aggregates. This is especially conspicuous under the low water-cement ratio. Even though the workability was affected, this problem could be overcome with developed chemical additive technology. The durability properties of concrete were approximately equal. Therefore, it is suggested that the aggregate gradation requirement of LWAC should be distinct from that of NWC. In high strength LWAC proportioning, following the standard gradation suggested by American Society for Testing and Materials (ASTM) is optional.


Author(s):  
Burhan Afzal

Abstract: Portland cement is used by the construction industries, which is known to be a heavy contributor of carbon dioxide emissions and environmental damage. Adding of industrial wastes like demolished old concrete OF structures, silica fume (SF) fly ash (FA) as additional cementing materials (SCMs) could result in a substantial reduction of the overall Carbon dioxide trace marks of the final concrete product. Use of these additional materials in construction industry especially in the making of concrete is highly challenging. Remarkable research efforts are needed to study about the engineering properties of concrete incorporating such industrial wastes. Present research is an effort to study the properties of concrete adding industrial wastes such as demolished concrete, FA and SF The improvement of properties of RCA concrete with the incorporation of two ureolytic-type bacteria, Bacillus subtilis and Bacillus sphaericus to improve the properties of RCA concrete. The experimental investigations are carried out by experts evaluate the improvement of the compressive strength, capillary water absorption and drying shrinkage of RCA concrete adding bacteria. Seven concrete mixes are manufactured using Portland slag cement (PSC) partially changed with SF ranging from 0 to 30%. The mix proportions were obtained as per Indian standard IS: 10262-2009 with 10% extra cement when SF is taken as per the above the construction practice by experts. Optimal dosages of SF for maximum values of compressive strength, tensile splitting strength and flexural strength at 28 days are determined. Keywords: Bacillus subtilis, Bacillus sphaericus, RCA, PSC, Silica Fume.


2012 ◽  
Vol 204-208 ◽  
pp. 4101-4104 ◽  
Author(s):  
Tzong Ruey Yang ◽  
Ta Peng Chang ◽  
Chun Tao Chen ◽  
Yuan Kai Lee ◽  
Bo Tsun Chen

In this paper, the metakaolin is used as the raw material with aluminosilicate compounds to produce the geopolymer. The effects of three levels of two major controlling factors, the degree of polymerization of the activating solution (weight ratio of SiO2 to Na2O) of 0.4, 0.7 and 1.0 and the weight ratio of liquid to solid (L/S) of 0.7, 0.85 and 1.00 on the engineering properties of geopolymer are investigated. The experimental results show that, at age of 28 days, the compressive strength increases from the lowest 37.33 MPa (SiO2/Na2O = 0.4 and L/S = 0.7) to the highest 71.21 MPa (SiO2/Na2O = 0.7 and L/S = 0.7). While, the thermal conductivity increases from the lowest 0.39 w/mk (SiO2/Na2O = 0.4 and L/S = 1.0) to the highest 0.761 w/mk (SiO2/Na2O = 1.0 and L/S = 0.7).


Author(s):  
Robert F. Keefer

Micronutrients needed by plants are Cu, Fe, Mn, Zn, B, Mo, Cl, Ni, Co, V, Si, and Na. The required amounts of each of these elements is very small but still essential for desirable plant growth and reproduction. These elements must be applied to soils cautiously for the range between deficient and toxic is very small. It is unwise to use a fertilizer containing all of these micronutrients. Any one of them may already be high enough in soils to cause toxicity from that particular element. If a micronutrient is suspected of being deficient, it would be wise to get soil tests and plant tissue tests to corroborate your suspicions. If a micronutrient is deficient, one should apply only the amount recommended but no more. Sometimes a toxicity of an element is more difficult to correct than a deficiency. Copper, iron, manganese, cobalt, and zinc can be present in soils as (a) several types of precipitates, (b) adsorbed onto the surface of soil particles, (c) present in primary minerals (rocks) and secondary minerals (clays), and (d) present as complex ring compounds. These forms may or may not be available to plants. Precipitates of Cu, Fe, Mn, or Zn often form in soils at high pH (after liming Fig. 14.1). This may occur in soils near buildings from the lime used in the mortar. Soil acids dissolve the lime into Ca++ or Mg++ that migrate into the soil raising the pH and cause these micronutrients to precipitate. Often an Fe deficiency is evident, particularly on acid-loving plants, such as azaleas, rhododendrons, or hollies. If this is extensive, the soil near the buildings may need to be replaced. With limited areas, the soil can be acidified by adding elemental S near the plants affected. The elements Cu, Fe, Mn, and Zn can exist as soluble forms or precipitates, depending on the pH of the soil. The soluble forms as cations are present when soils have poor internal drainage (poorly drained soils), whereas the oxides of these elements are present where the soil is well aerated.


2020 ◽  
Vol 10 (21) ◽  
pp. 7726
Author(s):  
An Thao Huynh ◽  
Quang Dang Nguyen ◽  
Qui Lieu Xuan ◽  
Bryan Magee ◽  
TaeChoong Chung ◽  
...  

Geopolymer concrete offers a favourable alternative to conventional Portland concrete due to its reduced embodied carbon dioxide (CO2) content. Engineering properties of geopolymer concrete, such as compressive strength, are commonly characterised based on experimental practices requiring large volumes of raw materials, time for sample preparation, and costly equipment. To help address this inefficiency, this study proposes machine learning-assisted numerical methods to predict compressive strength of fly ash-based geopolymer (FAGP) concrete. Methods assessed included artificial neural network (ANN), deep neural network (DNN), and deep residual network (ResNet), based on experimentally collected data. Performance of the proposed approaches were evaluated using various statistical measures including R-squared (R2), root mean square error (RMSE), and mean absolute percentage error (MAPE). Sensitivity analysis was carried out to identify effects of the following six input variables on the compressive strength of FAGP concrete: sodium hydroxide/sodium silicate ratio, fly ash/aggregate ratio, alkali activator/fly ash ratio, concentration of sodium hydroxide, curing time, and temperature. Fly ash/aggregate ratio was found to significantly affect compressive strength of FAGP concrete. Results obtained indicate that the proposed approaches offer reliable methods for FAGP design and optimisation. Of note was ResNet, which demonstrated the highest R2 and lowest RMSE and MAPE values.


2020 ◽  
Vol 998 ◽  
pp. 323-328
Author(s):  
Achmad Bakri Muhiddin ◽  
Marthen M. Tangkeallo

In remote areas, most roads still use pavements that are very sensitive to climate change, especially those using clay pavements with high plasticity. In addition to the issue of cost, the difficulty of obtaining a proper source of material is another problem that has led to soaring prices for materials. In this regard, a study was conducted using local materials, namely zeolite as a stabilizing material added with waterglass as activating agent. The research began with samples of laterite soil and natural zeolite for XRD test (microstructure testing), and then testing for laterite soil’s index properties and engineering properties, namely Unconfined Compressive Strength and CBR value. The purpose of the test is to determine the correlation between the Unconfined Compressive Strength (UCS) and the soil bearing capacity (CBR) caused by adding zeolite as stabilizer material and waterglass as activator with increasing curing time. Laterite soils contain a brownish red iron oxide. The stabilizing material zeolite contains a crystalline mineral of alumina silicate SiO2. While waterglass composed of sodium meta silicate. Stabilization carried out by mixing 4%, 8%, 12%, 16%, and 20% of zeolite with addition of 2% waterglass, percentage was measured based on soil dry weight. Specimens were tested at curing time of 0, 7, 14, and 28 days. The test result shows increasing UCS and CBR values with increasing percentage of zeolite. At mix of 20% zeolite and 2% waterglass, the unconfined compressive strength reaches 23.54 kg/cm2 with CBR value 58% at 28 days of curing time.


Sign in / Sign up

Export Citation Format

Share Document