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Misconstruing that buried pipelines do not lead to catastrophic failures while other constructed structures are deemed susceptible to failure is not uncommon. This paper presents some innovative research methodology underpinned by case studies to endorse that design and construction of buried pipelines need amenable interdisciplinary communications between materials, hydraulic, geotechnical, structural, and construction engineers. An initial outline sets the scene for the gravity of consequences from buried pipeline failures. The paper proceeds to expound related reasons and intelligent infrastructure solutions arising from forensic investigations of such failures. The inevitable influences from material aging and geo-environmental effects on a variety of pipeline projects are then presented. It is more the reason that smart contractors need to vigilantly adhere to contract specifications of a project, appreciating the significance of the variability in the foundation soil, geo-environmental, and construction hazards. Further attempts were made to distinguish between pipeline failures consequential to factors over and above soil–pipeline interaction influenced by soil loads surrounding the pipe. Shortsighted, hasty decisions in construction practice to economize on time and construction costs will lean toward collapse, resulting in unforeseen ancillary costs. The author shares his expert evidence experience and innovative, sustainable research solutions covering different failure scenarios. The paper further presents unorthodox geotechnical and material investigations and smart engineering solutions carried out by his numerous postgraduate researchers and others within a pipeline research group in the UK. The cases cited will hopefully enthuse the quest of interested readers to develop further through the references cited, the need for lateral and logical thinking “outside the box” for forensic geotechnics and pipeline engineering.

Moisture and heat management properties of Hemp and Stone Wool insulations were studied by mounting them between a hot and a cold climate chamber. Both insulations were exposed to identical hygrothermal boundary conditions. Quasi steady state and dynamic tests were carried out at a range of relative humidity exposures. The likelihood of interstitial condensation was assessed and equivalent thermal conductivity values of the insulations were determined. The adsorption-desorption isotherms of the insulations were also determined in a dynamic vapour sorption (DVS) instrument. It was observed that the likelihood of condensation was higher in Stone Wool insulation than in Hemp insulation. Hemp insulation performed better in managing moisture due to its high hygric inertia and water absorption capacity. It was observed that the equivalent thermal conductivity of Stone Wool insulation was dependent on enthalpy flow and phase change of moisture. The equivalent thermal conductivity of Hemp insulation was close to its declared thermal conductivity in dynamic conditions when high relative humidity exposures were transient. In quasi steady state boundary conditions, when the insulation was allowed to reach the equilibrium moisture content at ranges of relative humidity, there was a moisture dependent increase of thermal conductivity in Hemp insulation.

This paper presents the use of software modelling as a tool to study the impact of hydraulic “resistivity” on the contaminant transport through bentonite-based containment barriers. A sensitivity analysis on the predicted data was carried out by varying the boundary conditions as well as the hydraulic resistance to flow through varying contaminant transport parameters. Accordingly, both advective and diffusive flow processes are considered as that which resists the flow. In particular, the effect on the contaminant migration due to desiccation cracking is explored. Laboratory evidence is provided and discussed to show how the initial microstructure of the clay influences the development of subsequent macro structural features such as shrinkage crack patterns. The effect of these cracks and the intensity of cracking on the contaminant migration are modelled and pragmatically discussed. Additionally, the effect on the hydraulic conductivity of bentonite-based barriers, when permeated with non-standard liquids is discussed and a typical analytical output is presented.

An in situ experiment on a full-scale timber frame test building was carried out to study the hygrothermal performance of wood-hemp composite insulation in timber frame wall panels with and without a vapour barrier. The heat transfer properties and the likelihood of mould growth and condensation in the panels were compared. Step changes in the internal relative humidity were performed to explore the effects of high, normal and low internal moisture loads on the wall panels. No significant difference in the average equivalent thermal transmittance (U-values) between the panels with and without a vapour barrier was observed. The average equivalent U-values of the panels were close to the U-values calculated from the manufacturers’ declared thermal conductivity values of the insulation. The likelihood of condensation was higher at the interface of the wood-hemp insulation and the oriented strand board (OSB) in the panel without a vapour barrier. In terms of the parametric assessment of the mould germination potential, the relative humidity, the temperature and the exposure conditions in the insulation-OSB interfaces of the panel without a vapour barrier were found to be more favourable to the germination of mould spores. Nonetheless, when the insulations were dismantled, no mould was visually detected.

This paper compares some geotechnical properties of Kaolin, Laterite and Peat. Laterite was collected from Bukit Banang while Peat sample was collected from Parit Nipah, both locations were in Batu Pahat, Johor. Meanwhile, kaolin that was used in this research was manufactured kaolin. These soil samples were subjected to routine laboratory analysis and resulting data were analyzed statistically using a correlation analysis. A laboratory testing program consists of “Basic properties test” to obtain general information on the materials (e.g Natural moisture content, Atterberg Limit, Specific gravity, grain size analysis, chemical composition and pH) and “Geotechnical properties tests” to measure specific properties that characterize soil behaviour for design and constructability assessments (e.g Standard Proctor Test, Unconfined Compressive Strength and CBR).The results showed that the Natural/initial moisture content for laterite, peat and kaolin is 22.54%, 480.61% and 0.22% respectively. Meanwhile Specific gravity for each soil was in the range 1.50-2.79.It was also found that the pH of all soil is acidic which lay in the range of 3.76-5.95.The UCS for the optimally compacted sample of laterite is 445.77 kPa, kaolin is 199.23 kPa and for peat is 58.70 kPa. This paper summarizes the result of analysis performed on all tests conducted. Based on the results, the geotechnical property of the soil is a highly dependent with the type of soil and therefore, determining the soil characterization and the soil strength should be considered during the planning phase of any earthwork construction operation.

Innovative developments of hollow cellular mat for lightweight structure must satisfy sustainability, fit for purpose and optimize design concepts. However, such materials necessitate appropriate cutting technology to allow trimming and shaping operations to be easily carried out on an excessive porous and perhaps non uniformity nature. This paper presents a work that aims at studying the machinability of porous cellular mat using a newly innovative cutting technology. A large structure of vertical bandsaw has been fabricated to cut the product with the size of 1m (width) x 1m (height) x 1m (long). The systems also equipped with a feeding table and strong structure frame to avoid product shifting during the cutting operation. The surface integrity showed minimum deformation with uniformed direction of surface removal marks. The cutting technology developed in this study is suitable for the hollow cellular mat for its simple trimming and shaping process and fine surface profile.

Strength and deformation parameters of compacted soil are known to be related to soil type and moisture. However, little attention has been directed towards understanding the influence of compaction energy on soil type and moisture. This study considers the effect of different compaction energy on certain geotechnical properties of Kaolin and Laterite soil. This paper describes a laboratory study conducted to evaluate the relationship between soil type, soil moisture content with different compaction energy and strength characteristic. Specimens were compacted with impact energy at levels of 596 kg/m3(Standard Proctor) and 2682 kJ/m3 (Modified Proctor) over a wide range of moisture contents to determine dry unit weight, and Unconfined Compression Strength Test (UCS). Result shows that compaction energy is an important factor in determining soil strength that should be considered during the planning phase of any earthwork construction operation.

In this study, a laboratory investigation was conducted to examine the performance of TerraZyme on different soil types. Laterite and kaolin were treated with 2% and 5% TerraZyme to determine changes in the soils’ geotechnical properties. The obtained results were analysed and investigated in terms of compaction, Unconfined Compressive Strength (UCS) and California Bearing Ratio (CBR). The changes in geotechnical properties of the stabilised and unstabilised soils were monitored after curing periods of 0, 7, 15, 21 and 30 days. Changes in compaction properties, UCS and CBR were observed. It was found that laterite with 5% TerraZyme gave a higher maximum dry density (MDD) and decreased the optimum moisture content (OMC). For kaolin, a different TerraZyme percentage did not show any effect on both MDD and OMC. For strength properties, it was found that 2% TerraZyme showed the greatest change in UCS over a 30-day curing period. The CBR value of stabilised kaolin with 2% TerraZyme gave a higher CBR value than the kaolin treated with 5% TerraZyme. It was also found that laterite treated with TerraZyme gave a higher CBR value. Lastly, it can be concluded that TerraZyme is not suitable for stabilising kaolin; TerraZyme requires a cohesive soil to achieve a better performance.

Migration of liquids lead to embarrassing post construction scenarios such as that of leaks from roofs, potable water leaking from water tanks/ reservoirs, rising damp in walls with groundwater seeping into basement structures, leakage of water from ornamental lakes and ponds or leachate leakage into the environment from MSW landfill sites. Such failures demand immediate and expensive maintenance. A stringent control on structural and waterproof stability is deemed necessary for long term service life of structures and in particular underground and near surface structures. On a micro scale and over a longer time scale, the phenomenon of rising dampness occurs in older buildings with the groundwater rising up through walls, floors and masonry via capillary action. Even slower rates of contaminant fluid migration occur through landfill base liners. In this paper a variety of hydraulic barrier technologies is critically discussed against a backdrop of relevant case studies. The choice of an appropriate hydraulic barrier technology for a given scenario will depend also on the sustainability, financial affordability and subjective aesthetics.

Purpose – The purpose of this paper is to describe and discuss initial work to assess the moisture buffering performance of selected bio-insulations in lofts that suffer from excessive moisture following refurbishment. Design/methodology/approach – These conditions were then reproduced in a physical lab-based experiment such that the comparative performance of the bio-insulations and stone wool could be measured. Findings – It was found that the bio-insulations could remove over 60 per cent of the moisture in the loft air, and therefore reduce the risk of condensation and its severity. Research limitations/implications – The initial work reported here is indicative of the buffering potential of bio-insulations but further work is required to better quantify this performance. There is a need to further examine lofts with moisture problems and to produce reliable testing methods and protocols to be used when retrofitting loft insulation. Practical implications – Installers and specifiers of loft insulation should ensure that insulation is installed correctly, as with the drive to increase loft insulation levels the risks of damaging the building fabric through condensation are increasing. Social implications – Excessive moisture can damage the building fabric and create health problems. Using insulations that perform well across a range of performance criteria tend to favour bio-insulations, which have a far less harmful impact on the environment than do typical fossil-fuel based insulations. Originality/value – The paper presents preliminary findings that support arguments for specifying bio-insulations.

Past applications of electrical resistivity surveying have particularly focused on areas of subsurface ground investigations to locate boulder, bedrock, water table, etc. Traditionally, electrical resistivity surveys were directed by an expert geophysicist for data acquisition, processing and interpretation. The final outcome from the electrical resistivity technique was an anomaly image that helped describe and demarcate zones of challenging ground conditions. The anomalies highlighted uncertain geotechnical conditions that were often irregular and dependent on individual site condition, yielding a site-dependent electrical resistivity value (ERV) for the ground. This study therefore identifies co-relationships between ERV and some basic geotechnical properties (BGP) such as soil moisture content, grain size of geomaterial, density, porosity, void ratio, and Atterberg limit. Different soil samples were collected and tested under both field and laboratory conditions. Basic geotechnical properties of the samples were obtained immediately after the electrical resistivity measurements were made. It was shown that the electrical resistivity value was greatly influenced by the geotechnical properties, and thus the resistivity surveying technique is applicable to support and enhance the conventional stand-alone anomaly outcome that is traditionally used in ground investigation interpretation.

Applications of lightweight construction materials enable the design and construction in challenging, difficult and demanding scenarios. Construction materials with enhanced stiffness as in sandwich panels, large portable structures and floating foundations are examples of such materials. The advent of cellular structure technology has actively introduced innovation and enabled design and construction, meeting engineering requirements such as in the construction of the body of air crafts. Cellular mat structures present in the minimum, triple benefits in being lightweight, load sharing and minimising non-uniform deformation. This paper further explores the use of recycled plastic waste as the base material for an innovative geomaterial. The combination of cellular structure, mat structure and use of recycled waste material is a desirable development in manufacturing. Paper also outlines the techno social benefit of adopting such material in construction. Other application-specific benefits related to cellular mats are those like noise reduction, energy absorption, thermal insulation, mechanical damping. This paper specifically presents the development of a new multifunctional lightweight material is been proposed as an invective innovation for highway construction on challenging ground condition.

Plastic waste is a current major environmental concerns leading to long-term hazards. Recycling concept is the best practice to minimise the amount of plastic waste in the environment. This initiative promotes development of sustainable technology. Recently, plastics are gaining more recognition in construction field and are being applied widely due to its improved performance, versatility, durability and lightweight. In this study, the use of recycled polypropylene (rPP) and recycled high density polyethylene (rHDPE) as an alternative material for construction are investigated. The thermal degradation and mechanical properties were studied using thermogravimetric analysis (TGA) and tensile testing method respectively. TGA analysis conducted on recycled and virgin PP and HDPE showed that they have a stable composition. Moreover, TGA was also done to compare recycled and virgin material to assess the degradation process with respect to the total weight loss of samples. The results obtained indicate that the composition of rPP gives higher tensile strength. 100% rPP/rHDPE blend gave the best performance in mechanical properties and have a lower degradation temperature which are requirements for the sintering process necessary in this research study, to produce new lightweight product.

In the past, most of the soil electrical resistivity charts were developed based on stand-alone geomaterial classification with minimal contribution to its relationship to some of geotechnical parameters. Furthermore, the values cited a very wide range of resistivity with sometimes overlapping values and having little significance to specific soil condition. As a result, it created some ambiguities during the interpretation of observations which were traditionally based on qualitative anomaly judgments of experts and experienced people. Hence, this study presents soil resistivity values based on laboratory experiment with a view to predict the soil moisture content and density in loose and dense soils. This study used a soil box and a resistivity meter to test a clayey silt soil, increasing its water usage from 1-3% based on 1500 gram of dry soil. All the moisture contents and density data were observed concurrently with 25 electrical soil resistance observations being made on the soil. All testing and formula used were in accordance with that specified in BS1377 (1990). It was apparent that the soil resistivity value was different under loose (L) and compact (C) condition with moisture content (w) and density (ρbulk) correlations being established as follows; ρbulk(C) = 2.5991ρ-0.037, ρbulk (L) = -0.111 ln (ρ) + 1.7605, w(L) = 109.98ρ-0.268, and w(C) = 121.88ρ-0.363 with determination coefficients, R2 that ranged between 0.69 0.89. This research therefore contributes a means of predicting these geotechnical parameters by related persons such as geophysicist, engineers and geologist who use these resistivity techniques in ground exploration.

Natural soils are an intimate mixture of solid, liquid and gas phases. This study establishes a correlation for moisture content and density of a soil with its electrical resistivity. In the past, most of the conventional geotechnical site investigation required bulky and heavy equipment to determine the geotechnical parameters necessary for design and construction purposes. Consequentially, time and cost of the project is increased especially when dealing with some difficult site such as on mountainous terrain. This study is based on laboratory soil box resistivity meter observations made on soils mixed with additions of consistent increments of 1-5 % of water to 1500 gram of remolded soils in loose condition. At least 24 repetitive resistivity test observations were made and the moisture content and soil density was determined concurrently for each of the tests. The observations showed that the electrical resistivity variation decreased in a curvilinear manner with increasing percentage of moisture content. A regression equation and coefficient of determination, R2 for moisture content against soil electrical resistivity value was established by moisture content, w = 152.87ρ-0.312 (ρ = soil electrical resistivity) and R2 = 0.7718 respectively. While a regression equation and R2 value for bulk density versus soil electrical resistivity value was observed to be ρbulk = -0.107 ln (ρ) + 1.7249 and 0.7016 respectively. Hence, a viable method is demonstrated where the electrical resistivity value was applicable and has a great potential for geotechnical data prediction of parameters such as moisture content and soil density.

This paper discusses the resilient behaviour of various materials of high rigidity, high elasticity and of particulate materials. The resilient behaviour is measured by the resilient modulus (Mr) test which is the mechanical response of soils to a dynamic cyclic load which simulates traffic loading conditions and it is an important parameter in the design of both flexible and rigid pavements. The materials used are of a concrete cylinder, a rubber sample and particulate materials which are sands of different particle size and shape classification. The design resilient modulus follows a constitutive model and it is used to compare the resilient behaviour of each material. The constitutive model shows that the design resilient modulus is affected by the particulate characteristics and how it can be related to a stiff and flexible material.

Morphology properties of naturally occurring sandy soil deposits are a consequence of the past geological transport history which gives rise to their different shape and size distributions. Five sand samples with different particle size and shape distributions were analysed statistically. Cluster analysis, performance indicators and probability distributions were used to find a representative shape parameter value. Static and dynamic tests were also contemporarily done to study the shear characteristics of the samples. Dimensionless relationships of the critical shear stress (τcr) normalised with respect to the normal stress (σN) against the representative values are presented. Dynamic testing on the samples showed that the modulus reduction curve (G/Gmax) and damping ratio (D) were also dependent on the morphology characteristics of the sand samples.

The science of the particle level interaction of sandy soil on the macroscale behaviour is governed by the particle shape and size. Sands are cohesionless and the characteristics of its shear strength (A˜peak and A˜cr) are entirely dependent on the density, normal stress and the interparticle reaction of the soil structure. The shearing deformation of sand has also led to a phenomenon called dilatancy (Iˆ). In this study, well graded sand (SW), poorly graded uniform sand (SPuKahang), gap graded sand (SPg) from Kahang Malaysia and also (SPuL.Buzzard) uniform Leighton Buzzard sand from United Kingdom were tested in a direct shear box apparatus. The shapes of the sand particles were quantified using the images obtained from a digital microscope. Results from published studies were also analyzed. It was found that the A˜peak, A˜cr and Iˆ was the highest for (SW) when compared to the others with similar relative densities (Dr). High normal stresses gave very little variations in dilation angle (Iˆ) between the samples tested as compared to the lower normal stress. The correlation between (A˜peak - A˜cr) and Iˆ is also a useful measure of the enhancement of strength due to dilatancy. This research also contributes to predicting potential dilatancy occurrence based on the sand morphology. (Keywords: Sand, direct shear box test, friction angle, angle of dilatancy, size and shape)

Moisture desorption observations from two bentonite clay mats subjected to ten environmental zones with individually different combinations of laboratory-controlled constant temperatures (between 20 °C and 40 °C) and relative humidity (between 15% and 70%) are presented. These laboratory observations are compared with predictions from mathematical models, such as thin-layer drying equations and kinetic drying models proposed by Page, Wang and Singh, and Henderson and Pabis. The quality of fit of these models is assessed using standard error (SE) of estimate, relative percent of error, and coefficient of correlation. The Page model was found to better predict the drying kinetics of the bentonite clay mats for the simulated tropical climates. Critical study on the drying constant and moisture diffusion coefficient helps to assess the efficacy of a polymer to retain moisture and control desorption through water molecule bonding. This is further substantiated with the Guggenheim–Anderson–De Boer (GAB) desorption isotherm model which is presented.

Challenging, problematic and non-uniform ground conditions are a night mare to geotechnical engineers tasked with the design and construction of buildings and transport infrastructure. These often suffer undesirable structural settlements. Designing within the current understanding of geotechnics; settlement in peat and organic soils need to be recognised to include the known “primary and secondary consolidation characteristics” and the lesser known “tertiary consolidation phase”. These eventually contribute cumulatively to the consequential uneven and hazardous “bumpy road” surfaces. Undulating flexible road pavements result primarily from the transference of the heavy self-weight of the embankment fill to yielding and non-uniform subgrade. The adoption of conventional design/repair methods such as pile, vertical drain, soil replacement and soil stabilisation are expensive and inappropriate in very soft ground conditions. These then lead to unjustifiably high and repetitive maintenance costs. There being no one quick fix solution for all; pragmatic research must necessarily identify the best/progressively improved practical and sustainable solution. A viable solution is to develop criteria and explore the concept of a “masonry arch bridge structure/lintel-column structure” and adopting sustainable materials through pragmatic searching for appropriate recyclable waste materials. This will lead to the basis for a sustainable, innovative, strong, stiff, permeable composite mat structure that can be used on soft and/or yielding ground conditions. Conceptual lightweight fill technology including the popularly used expanded polystyrene (EPS) and the innovative composite mats recently being developed by the research team are outlined.

Soils at many sites do not always have enough strength to bear the structures constructed over them and some of the soil may need to be stabilized in order to improve their geotechnical properties. In this paper, routine laboratory tests were critically carried out to investigate the efficacy of lignin in improving the strength behaviour of the soils. Two different soil samples (laterite and kaolin) were studied and mixed with different proportions of lignin (2% and 5% of dry weight of soil), respectively. Unconfined Compressive Strength (UCS) characteristics evaluated in this study were done on samples at their maximum dry density and optimum moisture content (obtained from compaction tests). The UCS tests on all the specimens were carried out after 0, 7, 15, 21 and 30 days of controlled curing. The research results showed that the addition of lignin into kaolin reduced its maximum dry density while giving progressively higher optimum moisture content. Contrarily, with the laterite soil, both maximum dry density and optimum moisture content simultaneously increased when lignin was added into the soils. The UCS results showed that the the stabilized laterite with 2% lignin continued to gain strength significantly at a fairly steady rate after 7 days. Unfortunately, lignin did not show a significant effect in kaolin.

One of the key properties of hemp insulation is its moisture adsorption capacity. Adsorption of moisture can increase both thermal conductivity and heat capacity of the insulation. The current study focuses on the effect of moisture induced thermal mass of installed hemp insulation on the whole building energy use. Hygrothermal and thermal simulations were performed using the CIBSE TRY weather data of Edinburgh and Birmingham with the aid of following simulation tools: WUFI and IES. Following simplified building types were considered: building-1 with dry hemp wall and loft insulations, building-2 with moistened hemp wall and loft insulation and building-3 with stone wool insulation. It was observed that the overall conditioning load of building-1 was 1.2 to 2.3% higher than building-2 and 3. However, during the summer season, the cooling load of building-2 was 3-7.5% lower than the other buildings. It implies that, moistened insulation can potentially mitigate the effect of increasing cooling degree days induced by global warming.

Conceptual developments are underpinned by the intellectual process of constant reviewing and developing innovative research ideas into realistic design. There exists no one quick fix, fit for purpose solution to ensure stability of structures being constructed on a wide range of demanding ground conditions and variety of project constraints. Routine highway design and construction technology conformingly adopt only conventional fill methods and thus fail even to address adequately the less favoured conditions in challenging situations: a high initial construction cost arising from a full replacement of existing unfavourable soil conditions or an unsustainable construction design leading to a condition of rapid disintegration requiring regular expensive and disruptive highway maintenance activity. Undulating road embankment surfaces result from the transference of heavy self-weight of the embankment fill on yielding and non-uniform subgrade such as in peat soils. The Manitoba Water Services Board [1] specifies four classes of fills (viz; common, compacted common, compacted select granular backfill and unshrinkable backfill) for backfilling of pipeline trenches. Both conventional and alternatively sustainable backfills are discussed in this paper with new and appropriate technology opening doors with other tangible benefits for innovative and cost saving outcomes for differing construction scenarios.

An in situ experiment in a full scale timber frame test building was carried out to compare the hygrothermal performance of Hemp and Stone Wool insulations of identical thermal conductivity. Hemp and Stone Wool insulations were installed in timber frame wall panels without vapour barrier. The comparison was made in terms of heat transfer properties, likelihood of mould growth and condensation. Step changes in internal relative humidity were performed to explore the effect of high and normal internal moisture load on the wall panels. No significant difference between the average equivalent thermal transmittance (U-values) of the panels incorporating Hemp and Stone Wool insulations was observed. The average equivalent U-values of the panels were closer to the calculated U-values of the panels based on the manufacturers’ declared thermal conductivity of Hemp and Stone Wool insulations. It was observed that the placement of heat flux sensor along the depth of the insulation had significant influence on the measured equivalent U-value of the panels during high internal moisture load. The frequency and likelihood of condensation was higher in the interface of Stone Wool and Oriented Strand Board (OSB). In terms of the parametric assessment of mould germination potential, relative humidity, temperature and exposure conditions in the insulation-OSB interfaces were found to be favourable to germination of mould spore. However, when the insulations were dismantled, no mould was visually detected.

The paper presents the results of a laboratory investigation on the hygric properties of five hemp insulation materials commercially available in the UK. The hemp fibre content varies between 30% and 95% in the total fibre content of the insulation materials examined. The adsorption–desorption isotherm, moisture buffer value, vapour diffusion resistance factor and water absorption coefficient were determined for the insulation materials investigated. The results showed that the hygric properties of the hemp insulation materials could vary widely depending on the constituents and fibrous structure. The considerable differences noted in the hygric properties of the insulation materials examined could potentially influence their hygrothermal performance as part of a building thermal envelope.

Electrical resistivity technique has become a famous alternative tool in subsurface characterization. In the past, several interpretations of electrical resistivity results were unable to be delivered in a strong justification due to lack of appreciation of soil mechanics. Traditionally, interpreters will come out with different conclusion which commonly from qualitative point of view thus creating some uncertainty regarding the result reliability. Most engineers desire to apply any techniques in their project which are able to provide some clear justification with strong, reliable and meaningful results. In order to reduce the problem, this study presents the influence of basic physical properties of soil due to the electrical resistivity value under loose and dense condition. Two different conditions of soil embankment model were tested under electrical resistivity test and basic geotechnical test. It was found that the electrical resistivity value (ERV, ρ) was highly influenced by the variations of soil basic physical properties (BPP) with particular reference to moisture content (w), densities (ρbulk/dry), void ratio (e), porosity (η) and particle grain fraction (d) of soil. Strong relationship between ERV and BPP can be clearly presents such as ρ ∞ 1/w, ρ ∞ 1/ρbulk/dry, ρ ∞ e and ρ ∞ η. This study therefore contributes a means of ERV data interpretation using BPP in order to reduce ambiguity of ERV result and interpretation discussed among related persons such as geophysicist, engineers and geologist who applied these electrical resistivity techniques in subsurface profile assessment.

This paper outlined the important role played by public transport to meet the demand of business and social life. The paper reviewed the type of bus services, quality of service in the bus operation that influences the passenger decision and also the role of bus provider and bus driver. An improved understanding of the bus operation is important for a well managed bus services. Maintaining a high standard of quality in service and performance is of paramount importance to encourage people to make public transport their preferred choice.

Climate change issues have a significant impact on our environment. In this paper, development and use of innovative green technology products to meet the current pressing geo environmental challenges are presented. The environments addressed include contaminated water streams, landfills, challenging foundations, recycling wastes, highway slope failures and manufactured aggregates. Green technology develops and supports a strategy to address sustainability in the environment.

Electrical resistivity technique has become a popular alternative tool by the geotechnical engineers in subsurface investigation. This study presents the influence of soil electrical resistivity value (ERV) due to the different types of electrical resistivity array used in practice. The dissimilarity of ERV was become a popular debate by the engineers which posses less fundamental knowledge in this area. In the past, the theory of electrical resistivity technique was less being discovered by the engineer which creates lots of black boxes during the utilization of electrical resistivity method (ERM) in engineering purposes. Hence, the result which produced from the ERM was difficult to deliver in a sound of definitive ways due to lack of knowledge and experienced of most engineers. Hence, this study presents the influence of soil ERV due to the different types of array used with particular reference to as Dipole-dipole and Pole-dipole. A line of electrical resistivity imaging was performed on small embankment of sandy and lateritic soil with different types of array using ABEM SAS (4000) equipment. Three in line of soil samples were tested for moisture content (w) test immediately after the electrical resistivity data acquisition was completely measured. Moreover, particle size distribution test also was performed for all soil samples in order to support the findings. It was found that the ERV was never be the same for each types of array used even on the same particular location of the survey line. However, it was found that there was a consistent relationship between ERV and moisture content for both types of soil tested which can be represent by ERV 1/w. Hence, it was found that ERV produced was relative to the types of array used during the field measurement. Each types of array were applicable to be used in subsurface profiling and its selection was subjected to the target of interest.