scholarly journals COMPRESSIBLITY OF PEAT SOIL IMPROVED WITH POLYURETHANE

2019 ◽  
Vol 31 (1) ◽  
Author(s):  
Ismacahyadi Bagus Mohamed Jais ◽  
Diana Che Lat ◽  
Tengku Nur Dalila Tengku Endut
Keyword(s):  
Polyurethane Foam ◽  
Peat Soil ◽  
Optimum Ratio ◽  
Overburden Pressure ◽  
Lightweight Material ◽  
Oedometer Test ◽  
Pu Foam ◽  
Foam Stabilization ◽  
Underlying Soil ◽  
Very High

This research investigated the compressibility of natural peat soil and peat soil improved with polyurethane foam. High natural moisture content, high compressibility, low bearing capacity and medium to low permeability is a problem and characteristic of a peat soil. This problem can be solved by reducing the compressibility of the peat soil. The objective of this study is mainly to prove whether the presence of polyurethane foam as a lightweight material on peat soil can reduce the compressibility of peat soil or otherwise. Fifteen samples of peat soil taken from Johan Setia, Klang were tested using Oedometer test with load is doubled at each increment until it reaches the maximum required load which is 10kPa, 20kPa, 40kPa, 80kPa, 160kPa, 320kPa and 640kPa. Polyurethane foam is a lightweight material, therefore reduces the overburden pressure to the underlying soil, hence future settlement can be minimized to a tolerable settlement value. Based on the data obtained from analysis of Oedometer test, the compressibility parameters including void ratio, compression index and swelling index of the peat soil alone are very high which denoted extremely poor condition of the peat soil. The compressibility parameters improved significantly with the PU foam stabilization as PU act as a void filler for peat soil. A slight increase in the compressibility parameters are recorded with higher ratio of isocyanate.  However, the maximum pre-consolidation pressure recorded was with PU ratio of 1:1. Therefore, the optimum ratio for PU peat stabilization is in the ratio of 1:1.

scholarly journals CONSOLIDATION INTEGRATED BUOYANCY EQUATION FOR SOFT GROUND IMPROVED WITH LIGHTWEIGHT POLYURETHANE FOAM

2022 ◽  
Vol 23 (1) ◽  
pp. 1-12
Author(s):  
Diana Che Lat ◽  
Ismacahyadi Bagus Mohamed Jais ◽  
Nazri Ali ◽  
Nor Zurairahetty Mohd Yunus ◽  
Nor Hibatul Wafi Nor Zarin ◽  
...  
Keyword(s):  
Laboratory Test ◽  
Polyurethane Foam ◽  
Ground Improvement ◽  
Marine Clay ◽  
Overburden Pressure ◽  
Lightweight Material ◽  
Pu Foam ◽  
Consolidation Settlement ◽  
Alternative Equation ◽  
Rowe Cell

ABSTRACT: Consolidation settlement occurs when a saturated soil is subjected to an increase in overburden pressure that causes a volume change in the soil. When a lightweight material is used as a ground improvement, the stress is reduced as the soft soil is partially removed and replaced by the lightweight material. In addition, the improved ground with lightweight material has a potential to uplift due to the buoyancy of lightweight material. The uplift force reduces the stress imposed on the underlying soil as it acts in the upward direction, thus further reducing the consolidation settlement. This study is executed to produce an alternative equation for consolidation settlement incorporating the buoyancy effect for lightweight polyurethane (PU) foam as a ground improvement method. A Rowe Cell consolidation laboratory test was conducted on untreated marine clay soil as well as on improved marine clay with different thicknesses of lightweight PU foam. Validation of the laboratory test results was done by finite element analysis, PLAXIS 2D. The thickness of PU foam governs the buoyancy and the hydrostatic pressure of water displaced by PU foam, which is incorporated in the alternative equation.  The alternative consolidation settlement equation is applicable for ground improved with lightweight polyurethane foam and found to be more economical and practical as the buoyancy is taken into account in the equation. ABSTRAK: Mendapan pengukuhan berlaku apabila tanah tepu mengalami peningkatan tekanan beban yang menyebabkan perubahan isipadu tanah. Apabila bahan ringan digunakan sebagai penambahbaikan tanah, tekanan akan berkurang kerana sebahagian tanah lembut dikeluarkan dan diganti dengan bahan ringan. Selain itu, tanah yang diperbaiki dengan bahan ringan berpotensi untuk terangkat ke atas keranan daya apung bahan ringan. Daya angkat bahan ringan mengurangkan tekanan yang dikenakan ke atas tanah kerana daya bertindak ke arah atas, dan seterusnya megurangkan mendapan pengukuhan. Kajian ini dijalankan untuk menghasilkan persamaan alternatif bagi mendapan pengukuhan dan digabungkan dengan kesan daya apung untuk busa poliuretena ringan (PU) sebagai kaedah penambahbaikan tanah. Ujian makmal mendapan pengukuhan menggunakan peralatan Rowe Cell dilakukan pada tanah liat marin yang asal serta yang diperbaiki dengan ketebalan busa PU ringan yang berbeza. Pengesahan hasil ujian makmal dilakukan dengan analisis elemen terhingga, PLAXIS 2D. Ketebalan busa PU mempengaruhi daya apung dan tekanan hidrostatik bagi kedalaman air yang disesarkan oleh busa PU dan digabungkan dalam persamaan alternatif. Persamaan alternatif mendapan pengukuhan tersebut boleh digunapakai untuk pembaikan tanah menggunakan bahan ringan busa poliuretena dan didapati menjimatkan kos dan praktikal kerana keapungan diambilkira didalam persamaan tersebut.

Crush Response of Polyurethane Foam-Filled Aluminium Tube Subjected to Axial Loading

2014 ◽  
Vol 875-877 ◽  
pp. 534-541 ◽  
Author(s):  
Chawalit Thinvongpituk ◽  
Nirut Onsalung
Keyword(s):  
Energy Absorption ◽  
Polyurethane Foam ◽  
Testing Machine ◽  
Axial Loading ◽  
Asymmetric Mode ◽  
Pu Foam ◽  
Universal Testing ◽  
Collapse Mode ◽  
Empty Tube ◽  
Foam Filled

In this paper, the experimental investigation of polyurethane (PU) foam-filled into circular aluminum tubes subjected to axial crushing was presented. The purpose of this study is to improve the energy absorption of aluminium tube under axial quasi-static load. The aluminium tube was made from the AA6063-T5 aluminium alloy tubes. Each tube was filled with polyurethane foam. The density of foam was varied from 100, 150 and 200 kg/mP3P including with empty tube. The range of diameter/thickness (D/t) ratio of tube was varied from 15-55. The specimen were tested by quasi-static axial load with crush speed of 50 mm/min using the 2,000 kN universal testing machine. The load-displacement curves while testing were recorded for calculation. The mode of collapse of each specimen was analyzed concerning on foam density and the influence of D/t ratio. The results revealed that the tube with foam-filled provided significantly increment of the energy absorption than that of the empty tube. While the density of foam and D/t ratios increase, the tendency of collapse mode is transformed from asymmetric mode to concertina mode.

Uplift and Settlement Prediction Model of Marine Clay Soil e Integrated with Polyurethane Foam

2019 ◽  
Vol 9 (1) ◽  
pp. 481-489
Author(s):  
D.C. Lat ◽  
I.B.M. Jais ◽  
N. Ali ◽  
B. Baharom ◽  
N.Z. Mohd Yunus ◽  
...  
Keyword(s):  
Polyurethane Foam ◽  
Clay Soil ◽  
Ground Improvement ◽  
Soft Soil ◽  
Soft Clay ◽  
Effective Thickness ◽  
Marine Clay ◽  
Uplift Pressure ◽  
Pu Foam ◽  
Improvement Method

AbstractPolyurethane (PU) foam is a lightweight material that can be used efficiently as a ground improvement method in solving excessive and differential settlement of soil foundation mainly for infrastructures such as road, highway and parking spaces. The ground improvement method is done by excavation and removal of soft soil at shallow depth and replacement with lightweight PU foam slab. This study is done to simulate the model of marine clay soil integrated with polyurethane foam using finite element method (FEM) PLAXIS 2D for prediction of settlement behavior and uplift effect due to polyurethane foam mitigation method. Model of soft clay foundation stabilized with PU foam slab with variation in thickness and overburden loads were analyzed. Results from FEM exhibited the same trend as the results of the analytical method whereby PU foam has successfully reduced the amount of settlement significantly. With the increase in PU foam thickness, the settlement is reduced, nonetheless the uplift pressure starts to increase beyond the line of effective thickness. PU foam design chart has been produced for practical application in order to adopt the effective thickness of PU foam within tolerable settlement value and uplift pressure with respect to different overburden loads for ground improvement works.

Study on Multi-Axial Mechanical Properties of a Polyurethane Foam and Experimental Verification

2011 ◽  
Vol 311-313 ◽  
pp. 301-308
Author(s):  
Shou Hong Han ◽  
Zhen Hua Lu ◽  
Yong Jin Liu
Keyword(s):  
Mechanical Properties ◽  
Constitutive Model ◽  
Polyurethane Foam ◽  
Axial Compression ◽  
Axial Loading ◽  
Hydrostatic Compression ◽  
Model Parameters ◽  
Loading Conditions ◽  
Three Point Bending ◽  
Pu Foam

In order to investigate the multi-axial mechanical properties of a kind of PU (polyurethane) foam, some experiments in different loading conditions including uni-axial tension, uni-axial compression, hydrostatic compression and three-point bending were conducted. It is shown that the hydrostatic component influences yield behavior of PU foam, the yield strength and degree of strain hardening in hydrostatic compression exceed those for uni-axial compression. In terms of the differential hardening constitutive model, the evolution of PU foam yield surface and plastic hardening laws were fitted from experimental data. A finite element method was applied to analyze the quasi-static responses of the PU foam sandwich beam subjected to three-point bending, and good agreement was observed between experimental load-displacement responses and computational predictions, which validated the multi-axial loading methods and stress-strain constitutive model parameters. Moreover, effects of two foam models applied to uni-axial loading and multi-axial loading conditions were analyzed and compared with three-point bending tests and simulations. It is found that the multi-axial constitutive model can bring more accurate prediction whose parameters are obtained from the tests above mentioned.

scholarly journals Liquefaction of waste pine wood and its application in the synthesis of a flame retardant polyurethane foam

RSC Advances ◽  
2017 ◽  
Vol 7 (48) ◽  
pp. 30334-30344 ◽  
Author(s):  
Dizhu Yue ◽  
Oluwasola Oribayo ◽  
Garry L. Rempel ◽  
Qinmin Pan
Keyword(s):  
Flame Retardant ◽  
Polyurethane Foam ◽  
Sustainable Forestry ◽  
Pine Wood ◽  
Sustainable Resources ◽  
Pu Foam

The utilization of sustainable forestry waste resources in the production of polyurethane (PU) foam is a promising green alternative to the use of un-sustainable resources.

scholarly journals Recovery of Flexible Polyurethane Foam Waste for Efficient Reuse in Industrial Formulations

Polymers ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 1533 ◽  
Author(s):  
Gabriel Kiss ◽  
Gerlinde Rusu ◽  
Francisc Peter ◽  
Ionuț Tănase ◽  
Geza Bandur
Keyword(s):  
Polyurethane Foam ◽  
Atmospheric Pressure ◽  
Air Permeability ◽  
Hydroxyl Number ◽  
Pu Foam ◽  
Flexible Polyurethane Foam ◽  
Flexible Polyurethane ◽  
The Relationship ◽  
Pu Foams ◽  
Glycolysis Process

Ester polyurethane (PU) foam waste was reacted at atmospheric pressure in an autoclave and using microwaves with diethylene glycol (DEG) at different PU/DEG ratios in the presence of diethanolamine as a catalyst to find the glycolysis conditions that allow for the improved recovery of the PU foam waste and enable the recycling of the whole glycolysis product in foam formulations suitable for industrial application. The recycled polyol was characterized by dynamic viscosity, hydroxyl number, water content, and density, while thermal stability was assessed using thermogravimetric analysis. In the PU foam formulation, 1% and 5% of the glycolyzed material was reused. The relationship between the reuse level of the recycled polyol and the physical properties of the foam was thoroughly investigated. It was observed that both hardness and air flow decreased with increasing recycled polyol content, particularly for the polyester type foam, while tensile strength and compression strength increased. Depending on the amount of recycled polyol and catalyst used, polyether-based foams could be obtained with a low air permeability, needed in special applications as sealed foams, or with higher air permeability desirable for comfort PU foams. The results open the way for further optimization studies of industrial polyurethane foam formulations using a glycolysis process without any separation stage.

Ultrasonication assisted preparation of carbonaceous nanoparticles modified polyurethane foam with good conductivity and high oil absorption properties

Nanoscale ◽  
2014 ◽  
Vol 6 (22) ◽  
pp. 13748-13753 ◽  
Author(s):  
Hengchong Shi ◽  
Dean Shi ◽  
Ligang Yin ◽  
Zhihua Yang ◽  
Shifang Luan ◽  
...  
Keyword(s):  
Polyurethane Foam ◽  
Oil Absorption ◽  
Absorption Properties ◽  
Pu Foam ◽  
Flexible Pu Foam

A compressible, conductive, oil absorptive PU foam was facilely fabricated by ultrasonication induced carbonaceous nanoparticles onto flexible PU foam.

Preparation of Rigid Flame Retardancy Polyurethane Foam Material with Difficult Combusted Degree

2012 ◽  
Vol 535-537 ◽  
pp. 1151-1157
Author(s):  
Zhen Hui Qiu ◽  
Yuan Bao Sun ◽  
Zhan He Du
Keyword(s):  
Synergistic Effect ◽  
Polyurethane Foam ◽  
Flame Retardancy ◽  
Flame Retardants ◽  
Oxygen Index ◽  
Orthogonal Experiment ◽  
Foam Material ◽  
Pu Foam ◽  
Series Of Experiments

The flame retardants used for the rigid PU foam material were studied systematically in this paper and a series of experiments were carried out to test the oxygen index (OI) of it. The synergistic effect in the different flame retardants also be verified to achieve a well flame retardancy performance. The best ingredients were found out by an orthogonal experiment which can give the PU foam maeterial a difficult combusted degree with the oxygen index higher than 34.

scholarly journals Soil physicochemical and ethnobiological studies on the peat swamp forests of Southern Papua, Indonesia

2020 ◽  
Vol 21 (4) ◽  
Author(s):  
AKHMAD KADIR ◽  
ROSYE H.R. TANJUNG ◽  
SUHARNO SUHARNO ◽  
BASA T. RUMAHORBO ◽  
MUHAMMAD A. REZA
Keyword(s):  
Agricultural Research ◽  
Soil Analysis ◽  
Human Life ◽  
Peat Soil ◽  
Swamp Forest ◽  
Total N ◽  
Organic C ◽  
Peat Swamp ◽  
Very High

Abstract. Kadir A, Tanjung RHR, Suharno, Rumahorbo BT, Reza MA. 2020. Soil physicochemical and ethnobiological studies on the peat swamp forests of Southern Papua, Indonesia. Biodiversitas 21: xxxx.  Peatlands play an important role in human life, particularly its direct impact for the locals. People in peatlands depend on the availability of natural resources, including in Papua. The purpose of this research was to determine the important role of peatland areas in the lives of locals in southern Papua. The survey was conducted using the purposive sampling method. Peat soil samples were analyzed at the Balai Penelitian dan Teknologi Pertanian (Agricultural Research and Technology Center) (BPTP) Yogyakarta. The results showed that peatlands in the southern part of Papua, specifically Mappi District, belong to the fibric peats category. Soil analysis results showed that the average pH is 4.04 (acidic), organic C is 16.39% (high), total N is 1.12% (very high), and C/N ratio is 14.69(moderate). In general, the local’s knowledge about peat swamp is still low (26.98%), most of them (73.02%) do not know the existence of peat swamp forest. So far, people only know the forest as swamp forest. The locals still depend on forest areas to fulfill their daily needs, therefore peat areas land-use must be followed by wise management so that they can be made sustainable.

Plantar Pressure Analysis on Polyurethane Foam Materials in Footwear Exclusive for Overweight/Obese

2015 ◽  
Vol 749 ◽  
pp. 56-64
Author(s):  
Selvaraj Mathivanan ◽  
Gautham Gopalakrishna ◽  
Bhabendra Nath Das ◽  
Jagath Krishna
Keyword(s):  
Body Weight ◽  
Polyurethane Foam ◽  
Pressure Measurement ◽  
Plantar Pressure ◽  
Human Locomotion ◽  
The Body ◽  
Flat Foot ◽  
Pu Foam ◽  
High Bmi ◽  
Pressure Analysis

The overweight/obese individuals, in general, develop varied foot consequences during walk of life. The body weight and the prevalence of flat foot on the plantar surface are the primary indicators for the discomfort in respect of high BMI individuals. The body weight has been implicated as a factor in plantar heel [4, 11, 12]. The role of PU foam materials is of greater importance to render therapeutic advantages in footwear. The PU foam materials are widely used as varied elements in footwear and the consumers’ gain benefits and sense of satisfaction on comfort parameters. The main objective of research is to scientifically investigate the characteristics PU foam materials and explore these materials for plantar pressure analysis using In-shoe pressure measurement device on footwear designed and developed exclusively for overweight/obese individuals. The foot or thoses are commonly used in the conservative treatment of plantar fasciitis and are helpful to reduce the symptoms of strain during standing and ambulation [1,5,6,7].The investigation on PU foam materials and their efficacy as footwear inserts to provide therapeutic solutions especially for high BMI individuals has been not scientifically attempted in the domain of footwear research. Hence, the investigation on choosing ideal material thereby minimising the foot related problems being experienced by high BMI individuals is aimed at using plantar pressure analysis in this paper. The polyurethane foam materials possessing uniform substance of 4mm with varied densities such as D55, D75, D95 and D120 have been assessed on a range of physical characteristics such as Density, Hardness, Compression set followed Resiliency and cushioning behaviours. These materials are employed as foot inserts in footwear specifically designed and developed for overweight/obese individuals and the pressure analysis has been carried out using In-shoe pressure measurement method in the phase of human locomotion. Based on the results obtained on pressure analysis experiments, the ideal material aid in alleviating foot problems of high BMI individuals has been scientifically revealed and recommended to the beneficiaries.

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