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

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.

Self-conscious intelligent technological societies in the universe: a simple direct approach to probable astrosociological realistic scenarios

We present an alternative equation to estimate the probable number N of self-conscious intelligent technological societies (SCITSs) within the radius of the observable universe. This equation has only one poorly-known factor, Pc, the SCITS's formation probability, which can be estimated within an uncertainty by a factor of 102 (10−11 ≤ Pc ≤ 10−9) by applying the restriction imposed by Fermi's Paradox. The SCITS's formation rate for a typical spiral galaxy is then estimated as ≈1 civ Gyr−1. For a very optimistic maximum life expectancy ≈108 yr, the conclusion is that two civilizations never coexist in the same galaxy. Our estimated values for Pc are compatible with current biological and astrophysical evidences. We also propose an alternative astrosociological classification scheme which enables us to speculate about possible evolutionary paths for SCITSs in the universe. The so-called ‘Closed Bottle Neck’ (CBN) scenario suggests that civilizations are no exit evolutionary ways. We argue that simply there would not be interstellar travels nor Galaxy colonization or a Galactic Club. Thus Fermi's Paradox results eliminated, and the perspectives about the future of our own civilization may not be positive.

Experimental and Parametric Study on the Pull-Out Resistance of a Notched Perfobond Shear Connector

To ease the installation of perforating rebars through multi-holes, an alternative notched perfobond shear connector was proposed by cutting out the hole edge. This paper presents the test results of six pull-out specimens with conventional and notched perfobond shear connectors. The objective was to compare the failure modes and pull-out behaviors of perfobond shear connectors using circular holes and notched holes. Furthermore, the explicit finite element method was introduced and validated to generate parametric results for pull-out tests of notched perfobond shear connectors. A total of 33 parametric simulations were performed to further study the influences of several variables, including the hole diameter, the cut width, the perfobond thickness, the concrete strength, the diameter and strength of the rebar, and the strength of the structural steel. The experimental and numerical results were used to evaluate the previous equations for perfobond shear connectors. Finally, an alternative equation was proposed to estimate the pull-out resistance of notched perfobond shear connectors.

Trade Openness, Malnourishment and Income Inequality in South Asia

The paper empirically examines the effects of trade liberalization on undernourishment and income inequality in South Asian countries (sacs). For empirical analysis data is collected for the period 1972-2013 for five South Asian countries which include Bangladesh, India, Nepal, Pakistan and Sri Lanka. Panel fixed effect technique is used to estimate the model. The estimated results reveal that undernourishment has decreased while income inequality has increased in the region after liberalization. Economic development has reduced both undernourishment and income inequality. The results also endorse the role of agriculture factors in reducing undernourishment and the role of education, urban bias, and political democratization in reducing income inequality in sacs. These results are robust to alternative equation specifications and openness measures. The results provide some important policy implications. It is suggested that South Asian countries have to cope with the problem of malnourishment with high agriculture development and economic growth.

AN ALTERNATIVE METHOD OF ESTIMATING SPACE-MEAN SPEED

Average travelling speed usually applied in the traffic analysis as required in the fundamental traffic model. As one type of speed under the space-mean speed, most of the researchers have derived the equation to estimate the space-mean speed. There are a few factors that influence the speed changes along the segment. The fluctuate speed along the segment give an idea to average the spot mean speed from at least two points in order to estimate the space-mean speed. This paper explores an alternative method on how to convert the time-mean speed to space-mean speed that can represent the actual operating speed along segment using the average technique. A total of 18 data sets of time-mean speed and space-mean speed in six segments of uninterrupted two-lane single carriageway road were collected using automatic traffic counter and moving car observer, respectively. Two sets of automatic traffic counter were installed along the segment to record the spot speed and then converted to the time-mean speed, while the moving car observer were conducted concurrently to get the space-mean speed. The data sets were analysed using linear regression analysis. The results of summary of model show a strong relationship with coefficient of determination, R2=0.808, while ANOVA test results show the coefficient of constant and time-mean speed is not zero with p-value is less than 0.05 at confident level of 95%. The error obtained from this alternative equation are lesser than the established equation and it recommends that the alternative equation is acceptable.

Economics approaches the fork in the road. Labor self-financing and tax free compensations or toil of deficit and deflation

<p>The aim of this paper is pointing out the causes of persistent budget deficits, and the emergence of deflation. As a result of the theoretical analysis of capital and labor tandem the phenomenon of labor self-financing is revealed. Discerning the money-goods economy in the form of the two parallel streams of products, and money lead to the alternative equation of exchange, which indicates an acceptable credit size? The main outcome of this study is clarify that deflation is related to funding of work in the public sector by taxes. It results in imbalance between the value of the product and the money streams. If inflation is under control then deflation reveals itself. Additionally it is concluded that economics without deficit, inflation and deflation may exist. It is further claimed that in the present economics there is a correspondence between the amount of necessary issuance of money and the amount of salaries in the public sector.</p>