scholarly journals Long-Term Intruding Effects of Acid Rain on Engineering Properties of Primary and Secondary Kaolinite Clays

2016 ◽  
Vol 2 (3) ◽  
Author(s):  
Zeinab Bakhshipour ◽  
Afshin Asadi ◽  
Bujang B. K. Huat ◽  
A. Sridharan
Keyword(s):  
Acid Rain ◽  
Engineering Properties

Effect of Lime on Compaction, Strength and Consolidation Characteristics of Pontian Marine Clay

2015 ◽  
Vol 72 (3) ◽  
Author(s):  
Siaw Yah Chong ◽  
Khairul Anuar Kassim
Keyword(s):  
Construction Material ◽  
Soft Clay ◽  
Engineering Properties ◽  
Dry Density ◽  
Marine Clay ◽  
Maximum Dry Density ◽  
Stabilization Phase ◽  
Compaction Curve ◽  
Stabilized Soil

Marine clay is a problematic construction material, which is often encountered in Malaysian coastal area. Previous researchers showed that lime stabilization effectively enhanced the engineering properties of clay. For soft clay, both strength and consolidation characteristics are equally important to be fully understood for design purpose. This paper presented the effect of lime on compaction, strength and consolidation characteristics of Pontian marine clay. Compaction, unconfined compression, direct shear, Oedometer and falling head permeability tests were conducted on unstabilized and lime stabilized samples at various ages. Specimens were prepared by compaction method based on 95 percent maximum dry density at the wetter side of compaction curve. It was found that lime successfully increased the strength, stiffness and workability of Pontian marine clay; however, the permeability was reduced. Unconfined compressive strength of stabilized soil was increased by 49 percent at age of 56 days whereas compressibility and permeability was reduced by 48 and 67 percent, respectively. From laboratory tests, phenomenon of inconsistency in engineering characteristics was observed for lime stabilized samples below age of 28 days. This strongly proved that lime stabilized soil underwent modification phase before stabilization phase which provided the long term improvement.

Bridge 1-351 over Muddy Run: Design, Testing, and Erection of an All-Composite Bridge

2000 ◽  
Vol 1696 (1) ◽  
pp. 118-123 ◽  
Author(s):  
J. W. Gillespie ◽  
D. A. Eckel ◽  
W. M. Edberg ◽  
S. A. Sabol ◽  
D. R. Mertz ◽  
...  
Keyword(s):  
Large Scale ◽  
Flexural Rigidity ◽  
Limit State ◽  
Engineering Properties ◽  
Molding Process ◽  
Strength Limit ◽  
Large Scale Testing ◽  
Longitudinal Joint ◽  
Composite Bridge

Bridge 1.351 on Business Route 896 in Glasgow, Delaware, was replaced with one of the first state-owned all-composite bridges in the nation. Composites are lightweight construction materials that do not corrode, which results in benefits such as ease of construction and reduced maintenance costs. A summary of the design, large-scale testing, fabrication, erection, and monitoring of this bridge is presented. The bridge was designed to AASHTO load and resistance factor design specifications. A methodology was developed to incorporate the engineering properties of these unique composite materials into the design. The bridge consists of two 13 × 32 ft (3.96 × 9.75 m) sections joined by a unique longitudinal joint. The sections have sandwich construction consisting of a core [28 in. (71.12 cm) deep] and facesheets [0.4 to 0.6 in. (10.16 to 15.24 mm) thick] that provide shear and flexural rigidity, respectively. The composite bridge was fabricated with E-glass preforms and vinyl-ester resin, which offers excellent structural performance and long-term durability. Each of the sections was fabricated to near-net shape in a single step by a vacuum-assisted resin transfer molding process. The overall structural behavior has been accurately predicted with simple design equations based on sandwich theory for anisotropic materials. Large-scale testing of full-sized subcomponents was conducted to prove that the design satisfied deflection, fatigue, and strength limit states. A redundant longitudinal joint was designed that consisted of both an adhesively bonded vertical joint between sections and splice plates. Assembly procedures were developed, and transverse testing of the full-sized joint was conducted. Final bridge sections were proof-tested to the strength limit state. The construction phase included section positioning, joint assembly, and application of a latex-modified concrete wear surface. The bridge was reopened to traffic on November 20, 1998. Results from the long-term monitoring effort will be documented.

Evaluation of Durability and Permanent Deformation of Modified Road Base Construction Using Rovene® 4045 and Portland Cement Additives

2015 ◽  
Vol 1089 ◽  
pp. 228-234
Author(s):  
Mojtaba Shojaei Baghini ◽  
Amiruddin Ismail ◽  
Mohamad Rehan bin Karim
Keyword(s):  
Portland Cement ◽  
Permanent Deformation ◽  
Engineering Properties ◽  
Weight Changes ◽  
Permanent Strain ◽  
Road Base ◽  
Strain Behaviour ◽  
Wheel Tracking ◽  
Styrene Butadiene

Due to lack of previous study on applying polymer additives in road base construction, this research presents experimental results on the improvement of long-term road base performance by the addition of carboxylated styrene–butadiene emulsion (Rovene® 4045) and Portland cement. The specimens stabilized with Portland cement (0–6%) and Rovene® 4045 (5–10%) and then subjected to different stress sequences to study the wetting and drying (WD) and wheel tracking (WT) tests on the 7-day-cured specimens. Results of tests conducted to assess the specimens’ resistance to WD cycling showed that the addition of a 4% Portland cement–7% Rovene® 4045 mixture resulted in reductions of 86.99% in water absorption, volume changes of 88.55%, and weight changes of 92.84% relative to a sample with only 4% cement after 12 WD cycles. The permanent strain behaviour of the samples was assessed by the WT test. The results of WT test showed that the permanent deformation characteristics of the mixture were considerably improved by utilization of Rovene® 4045 modification, which resulted in reductions of 218.9% at 25 oC, and 356.8% at 50 oC in permanent strain of the mixture respectively. Therefore, this research nominates a new polymer additive having outstanding engineering properties and environmental friendly.

scholarly journals Flexural Strength Prediction Models for Soil–Cement from Unconfined Compressive Strength at Seven Days

Materials ◽  
2019 ◽  
Vol 12 (3) ◽  
pp. 387 ◽  
Author(s):  
Alaitz Linares-Unamunzaga ◽  
Heriberto Pérez-Acebo ◽  
Marta Rojo ◽  
Hernán Gonzalo-Orden
Keyword(s):  
Compressive Strength ◽  
Flexural Strength ◽  
Uniaxial Compressive Strength ◽  
Prediction Models ◽  
Road Construction ◽  
Engineering Properties ◽  
Construction Technique ◽  
Soil Cement ◽  
Over Exploitation

Soil–cement is an environmentally friendly road construction technique for base and subbase materials, which allows employing soils placed in the right-of-way of the road or in the surroundings, by improving its engineering properties. With this technique, it is possible to reduce the over-exploitation of quarries, the necessity of landfills and the pollutant gas emission due to the reduction of aggregate fabrication and transport. The manufacturing of soil–cement is generally controlled by means of the Uniaxial Compressive Strength (UCS) test at seven days, according to the regulations of each country. Nonetheless, one of the properties that best defines the performance of soil–cement is the Flexural Strength (FS) at long term, usually at 90 days. The aim of this paper is to develop new equations to correlate the UCS and the FS at long term and the UCS at seven days and at 90 days. Obtained results validate the proposed models and, hence, the flexural strength can be predicted from the Uniaxial Compressive Strength at seven days, allowing, if necessary, correcting measures (recalculation or rejection) in early stages of the curing time to be taken.

Long-Term Effects of Acid Rain: Response and Recovery of a Forest Ecosystem

Science ◽  
1996 ◽  
Vol 272 (5259) ◽  
pp. 244-246 ◽  
Author(s):  
G. E. Likens ◽  
C. T. Driscoll ◽  
D. C. Buso
Keyword(s):  
Acid Rain ◽  
Forest Ecosystem ◽  
Long Term Effects ◽  
Response And Recovery

Influence of Long-Term Fertilizer Treatments on the Fluorescence Spectroscopic Characterization of DOM Leached by Acid Rain From Red Soil

Soil Science ◽  
2013 ◽  
Vol 178 (11) ◽  
pp. 639-645 ◽  
Author(s):  
Jianchao Zhang ◽  
Weibing Xun ◽  
Zhen Zhu ◽  
Dongchu Li ◽  
Qirong Shen ◽  
...  
Keyword(s):  
Acid Rain ◽  
Spectroscopic Characterization ◽  
Red Soil

Study on the Long-Term Acid Rain Aging Behaviour of Polyamide 6

2009 ◽  
Vol 48 (3) ◽  
pp. 526-536 ◽  
Author(s):  
Ying Shu ◽  
Xiaohe Li ◽  
Lin Ye
Keyword(s):  
Acid Rain ◽  
Polyamide 6

Rethinking justice and fairness: the case of acid rain emission reductions

1995 ◽  
Vol 21 (2) ◽  
pp. 119-143 ◽  
Author(s):  
Cecilia Albin
Keyword(s):  
Distributive Justice ◽  
Acid Rain ◽  
Emission Reduction ◽  
Environmental Issues ◽  
Emission Reductions ◽  
Reduction Strategies ◽  
Systematic Reflection ◽  
Emission Reduction Strategies

A major problem in managing and ultimately resolving many environmental issues, transboundary and global in particular, is how to tackle the fundamental questions of distributive justice and fairness involved. Little systematic reflection and research have been devoted to these issues. The problem of acid rain is a prime example. Strategies to abate acid rain must, among other requirements, be viewed as fair and just if they are to be politically accepted, implemented and honoured in the long term. Research and actual negotiations in this area to date have, by contrast, focused almost exclusively on the generation and analysis of emission reduction strategies which are effective in economic and, more recently, environmental terms.

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