Abstract: The use of low quality concrete has been identified as one of the main causes of the incessant collapse of buildings in Nigeria. Emphasis has been on the use of poor quality aggregates, poor workmanship and the use of lean concrete mix with low cement quantity as the reasons for the low quality of concrete used for building construction in Nigeria. Surveys conducted revealed that in the construction of most privately owned buildings where concrete trial mixes and concrete compressive strength quality assurance tests are not conducted, concretes used for building constructions are produced using the 1:2:4 mix ratio irrespective of the cement grade/strength class. In this paper, the possible role of the use of inappropriate cement grade/strength class as a cause of the incessant collapse of building in Nigeria is investigated. Investigation revealed that the compressive strengths of concrete cubes produced with Portland-limestone cement grade 32.5 using 1:2:4 and 1:1.5:3 mix ratios are less than the 25MPa and 30MPa cube strengths generally recommended for building superstructures and foundations respectively. Conversely, the compressive strengths of concrete cubes produced with Portland-limestone cement grade 42.5 using 1:2:4 and 1:1.5:3 mix ratios exceed the 25MPa and 30MPa generally recommended for building superstructures and foundations respectively. Thus, it can be concluded that the use of inappropriate cement grade (Portland-limestone cement grade 32.5), particularly for the construction of building foundations is a potential cause of the incessant collapse of buildings in Nigeria. It is recommended that the Standards Organisation of Nigeria should embark on creating awareness for Nigerians, particularly, the home owners and the roadside craftsmen that Portland-limestone cement grade 32.5 should not be used for the construction of building load-carrying members, particularly, building foundations in order to reduce the incessant incidence of collapsed building.
Abstract: Chittagong is the commercial capital of Bangladesh.
Here Agrabad is one of the most commercial activity centers of
Chittagong. Due to many light industry and commercial land use,
Agrabad to CEPZ road at Agrabad is the only major road of
Chittagong port city which encompasses a huge number of vehicles
every day. It has many junctions which distribute traffic flow in
different roads. In these junctions vehicles gather at some conflict
point to create traffic jam and make the performance of the road
downward. This study is parallel focused on the existing level of
service with traffic volume, capacity, and speed by traffic survey.
After all of these analyses the performance of the road is determined
with finding the factors that influences the performance.
Abstract: In this paper, we investigated the effect of real valued transformation of the spectral matrix of the received data for Angles Of Arrival estimation problem. Indeed, the unitary transformation of Partial Propagator (UPP) for narrowband sources is proposed and applied on Uniform Linear Array (ULA).
Monte Carlo simulations proved the performance of the UPP spectrum comparatively with Forward Backward Partial Propagator (FBPP) and Unitary Propagator (UP). The results demonstrates that when some of the sources are fully correlated and closer than the Rayleigh angular limit resolution of the broadside array, the UPP method outperforms the FBPP in both of spatial resolution and complexity.
Abstract: This research aims to study the Zinc (Zn) concentration in fine particulate matter on Rajchawithee roadside in rush hour. 30 Samples were collected in Jun to August 2013 by 8 stage non-avaible cascade impactor. Each samples (filter paper) were digest with nitric acid and analyed by atomic absorption spectrophotometer for Zinc determination. The highest value for the mean fraction (18.00 ± 9.28%) is the size 9.0 – 110.0 micron follow by the range 3.3 – 4.7 micron (14.77 ± 14.66 %) and 1.1 – 2.1 micron (14.01 ± 11.77 %). The concentration of Zn in the particulate matter of range 0.43 – 0.7mm, 0.7 – 1.1 mm, 1.1 – 2.1 mm, 2.1 – 3.3 mm, 3.3 – 4.7 mm, 4.7 – 5.8 mm, 5.8 – 9.0 mm, 9.0 – 10.0 mm, were 41.56 – 217.62 mg/m3 (175.86 ±32.25 mg/m3), 152.60 – 217.24 mg/m3 (187.71 ± 17.42 mg/m3), 142.90 – 214.67 mg/m3(180.95 ± 18.71 mg/m3), 155.48 – 218.19 mg/m3(183.22 ± 19.94 mg/m3), 151.72 – 217.39 mg/m3(181.85 ± 17.57 mg/m3), 133.86 – 220.17 mg/m3 (178.78 ± 23.45 mg/m3), 160.00 – 220.35 mg/m3 (182.58 ± 18.08 mg/m3), 153.30 – 226.70 mg/m3 (181.52 ± 20.05 mg/m3), respectively. The Zn concentration in each size of particulate matter was not statistically significant different (p > .005)
Abstract: Diverse contaminants released into the environment through progress of urbanization and industrialization adversely affect human health. Among various sources of contaminants, especially, in big cities, automobiles play a significant role in aggravating the pollution. Various pollutants viz., heavy metals (Pb, Mn, Ni, Zn, As, Hg, Cd) and Polyaromatic hydrocarbons (Benzo-a-pyrene, fluoranthene, pyrene, benzo-b-anthracene, benzo-b-fluoranthene, acenaphthylene, fluorine, phenantherene, anthracene, chrysene, benzo-k-fluoranthene, benzo-e-pyrene, indenol-1,2,3-cd-pyrene, dibenzo-a,h-anthracene, benzo-ghi-perylene) are released by vehicles. Further, these pollutants are expected to cause severe mutagenic, genotoxic and carcinogenic effects. Considering this, many authors monitored the levels of pollution in roadside soil, water and plants. The present review focuses upon the analysis and effects of heavy metals and polycyclic aromatic hydrocarbons from the roadside samples.
Abstract: Rapid industrialization results in increased use of natural resources bring along serious ecological and environmental imbalance due to the dumping of industrial wastes. Principles of sustainable construction have to be accepted with regard to the consumption of natural resources and the production of harmful emissions. Cement is a great importance raw material in the building industry and today is its large amount used in the construction of concrete pavements. Concerning raw materials cost and producing CO2 emission the replacing of cement in concrete mixtures with more sustainable materials is necessary. To reduce this environmental impact people all over the world are looking for a solution. Over a period of last ten years, the image of fly ash has completely been changed from a polluting waste to resource material and it can solve the major problems of cement use. Fly ash concretes are proposed as a potential approach for achieving substantial reductions in cement. It is known that it improves the workability of concrete, extends the life cycle of concrete roads, and reduces energy use and greenhouse gas as well as amount of coal combustion products that must be disposed in landfills.
Life cycle assessment also proved that a concrete pavement with fly ash cement replacement is considerably more environmentally friendly compared to standard concrete roads. In addition, fly ash is cheap raw material, and the costs saving are guaranteed. The strength properties, resistance to a frost or de-icing salts, which are important characteristics in the construction of concrete pavements, have reached the required standards as well. In terms of human health it can´t be stated that a concrete cover with fly ash could be dangerous compared with a cover without fly ash. Final Multi-criteria analysis also pointed that a concrete with fly ash is a clearly proper solution.
Abstract: There is growing concern over increasing incidences of road accidents and consequent loss of human life in Qatar. In light to the future planned event in Qatar, World Cup 2022; Qatar should put into consideration the future deaths caused by road accidents, and past trends should be considered to give a reasonable picture of what may happen in the future. Qatar roads should be arranged and paved in a way that accommodate high capacity of the population in that time, since then there will be a huge number of visitors from the world. Qatar should also consider the risk issues of road accidents raised in that period, and plan to maintain high level to safety strategies. According to the increase in the number of road accidents in Qatar from 1995 until 2012, an analysis of elements affecting and causing road accidents will be effectively studied. This paper aims to identify and criticize the factors that have high effect on causing road accidents in the state of Qatar, and predict the total number of road accidents in Qatar 2022. Alternative methods are discussed and the most applicable ones according to the previous researches are selected for further studies. The methods that satisfy the existing case in Qatar were the multiple linear regression model (MLR) and artificial neutral network (ANN). Those methods are analyzed and their findings are compared. We conclude that by using MLR the number of accidents in 2022 will become 355,226 accidents, and by using ANN 216,264 accidents. We conclude that MLR gave better results than ANN because the artificial neutral network doesn’t fit data with large range varieties.
Abstract: With the increase in population along with economic prosperity, an enormous increase in the number and types of vehicles on the roads occurred. This fact brings a growing need for efficiently yet effectively classifying vehicles into their corresponding categories, which play a crucial role in many areas of infrastructure planning and traffic management.
This paper presents two vehicle-type classification approaches; 1) geometric-based and 2) appearance-based. The two classification approaches are used for two tasks: multi-class and intra-class vehicle classifications. For the evaluation purpose of the proposed classification approaches’ performance and the identification of the most effective yet efficient one, 10-fold cross-validation technique is used with a large dataset. The proposed approaches are distinguishable from previous research on vehicle classification in which: i) they consider both geometric and appearance attributes of vehicles, and ii) they perform remarkably well in both multi-class and intra-class vehicle classification. Experimental results exhibit promising potentials implementations of the proposed vehicle classification approaches into real-world applications.
Abstract: The main objective of this study was to investigate particulate matter concentration on main and secondary roadsides in urban area and study the concentration of some heavy metals including lead (Pb), zinc (Zn), copper (Cu) and cadmium (Cd) in particulate matter in the Bangkok area.
The averaged particle concentration for main roadsides is higher than secondary roadsides. The particulate matter less than 10 micron concentration contribute the majority of the Total Suspended Particulate matter for main roads and zinc concentrations were higher than copper and lead for both sites.
Abstract: Speed and traffic volume data are collected on different sections of four lane and six lane roads in three metropolitan cities in India. Speed data are analyzed to fit the statistical distribution to individual vehicle speed data and all vehicles speed data. It is noted that speed data of individual vehicle generally follows a normal distribution but speed data of all vehicle combined at a section of urban road may or may not follow the normal distribution depending upon the composition of traffic stream. A new term Speed Spread Ratio (SSR) is introduced in this paper which is the ratio of difference in 85th and 50th percentile speed to the difference in 50th and 15th percentile speed. If SSR is unity then speed data are truly normally distributed. It is noted that on six lane urban roads, speed data follow a normal distribution only when SSR is in the range of 0.86 – 1.11. The range of SSR is validated on four lane roads also.
Abstract: The Romain paths or roads offer a very interesting archaeological material, because they allow us to understand the history of human settlement and are also factors that increase territorial identity. Roman roads are one of the hallmarks of the Roman empire, which extends to North Africa. The objective of this investigation is to attract the attention of researchers of the importance of Roman roads and paths, which are found in Algeria, according to the quality of the materials and techniques used in this period our history, and to encourage other decision makers to protect and enhance these routes because the current urbanization, intensive agricultural practices, or simply forgotten, decreases the sustainability of this important historical heritage.
Abstract: This study investigates the causes, effects and remedies of traffic congestion which has become a common sight in most highways in Nigeria; Mowe/Ibafo section of the Lagos-Ibadan expressway was used as the case-study. 300 Structured questionnaires were distributed among the road users comprising drivers (Private and Commercial), passengers, pedestrians, traffic officers, church congregations, community leaders, Mowe/Ibafo residents, and other users of the road.
300 questionnaires were given out; the average of 276 well completed returned questionnaires formed the basis of the study and was analyzed by the Relative Importance Index (R.I.I.). The result from the study showed the causes of traffic congestion as inadequate road capacity, poor road pavement, poor traffic management, poor drainage system poor driving habit, poor parking habit, poor design junctions/round-about, presence of heavy trucks, lack of pedestrian facilities, lack of road furniture, lack of parking facilities and others. Effects of road congestion from the study are waste of time, delay movement, stress, accident, inability to forecast travel of time, fuel consumption, road rage, relocation, night driving, and environmental pollution. To drastically reduce these negative effects; there must be provision for adequate parking space, construction of proper drainage, enlarging the width of the road, rehabilitate all roads needing attention, public enlightenment, traffic education, hack down all illegal buildings/shops built on the right of way (ROW), create a separate/alternative root for trucks and heavy vehicles, provision of pedestrian facilities, In-depth training of transport/traffic personnel, ban all form of road trading/hawking, and reduce the number of bus-stop where necessary. It is hoped that this study will become the foundation of further research in the area of improve road traffic management on our major highway.
Abstract: Timber-concrete structures were recently introduced in Brazil as a viable option for bridge construction on side roads. Binding between timber and concrete is fundamentally important to assure the rigidity and performance of this structural system. The objective of this study was to assess the structural performance of a timber-concrete bridge prototype with width of 170cm and span of 400cm, whose binding among timber beams and concrete slabs was made with metal pins, obtained from CA 50 construction steel bars of 12.5mm diameter. It was possible to conclude, from the results obtained experimentally in laboratory, that the timber-concrete bridge prototype showed a good structural performance. This structural system provides an economical, rapid implementation solution, which may be used on side roads, favoring regional integration and agricultural production flow.
Abstract: Appropriate and progressive tool for analyzing behavior of low volume roads are probabilistic models used in reliability analyses. The necessary part of the probabilistic model is the deterministic model of structural behavior. The FE model of low volume roads is created in the ANSYS software. It is able to determine the state of stress and deformation in any point of the structure and thus generate data required for the reliability analysis. The paper compares two material constitutive models used for modeling of unbound non-homogenous materials used in low volume roads. The first model is linear elastic model according to Hook theory (H model), the second one is nonlinear elastic-plastic Drucker-Prager model (D-P model).
Abstract: Low volume roads are widely used all over the world. To improve their quality the computer simulation of their behavior is proposed. The FEM model enables to determine stress and displacement conditions in the pavement and/or also in the particular material layers. Different variants of pavement layers, material used, humidity as well as loading conditions can be studied. Among others, the input information about material properties of individual layers made from recycled materials is crucial for obtaining results as exact as possible. For this purpose the cyclic-load triaxial test machine testing of cyclic-load performance of materials is a promising test method. The test is able to simulate the real traffic loading on particular materials taking into account the changes in the horizontal stress conditions produced in particular layers by crossings of vehicles. Also the test specimen can be prepared with different amount of water. Thus modulus of elasticity (Young modulus) of different materials including recycled ones can be measured under the different conditions of horizontal and vertical stresses as well as under the different humidity conditions. Using the proposed testing procedure the modulus of elasticity of recycled materials used in the newly built low volume road is obtained under different stress and humidity conditions set to standard, dry and fully saturated level. Obtained values of modulus of elasticity are used in FEA.
Abstract: The purpose of this study is to analyze the visual
preference of patterns in pedestrian roads. In this study, animation was
applied for the estimation of dynamic streetscape. Six patterns of
pedestrian were selected in order to analyze the visual preference. The
shapes are straight, s-curve, and zigzag. The ratio of building's height
and road's width are 2:1 and 1:1. Twelve adjective pairs used in the
field investigation were selected from adjectives which are used
usually in the estimation of streetscape. They are interesting-boring,
simple-complex, calm-noisy, open-enclosed, active-inactive,
lightly-depressing, regular-irregular, unique-usual, rhythmic-not
rhythmic, united-not united, stable-unstable, tidy-untidy.
Dynamic streetscape must be considered important in pedestrian
shopping mall and park because it will be an attraction. So, s-curve
pedestrian road, which is the most beautiful as a result of this study,
should be designed in this area. Also, the ratio of building's height and
road's width along pedestrian road should be reduced.
Abstract: In this paper the influence of heterogeneous traffic on
the temporal variation of ambient PM10, PM2.5 and PM1
concentrations at a busy arterial route (Sardar Patel Road) in the
Chennai city has been analyzed. The hourly PM concentration, traffic
counts and average speed of the vehicles have been monitored at the
study site for one week (19th-25th January 2009). Results indicated
that the concentrations of coarse (PM10) and fine PM (PM2.5 and
PM1) concentrations at SP road are having similar trend during peak
and non-peak hours, irrespective of the days. The PM concentrations
showed daily two peaks corresponding to morning (8 to 10 am) and
evening (7 to 9 pm) peak hour traffic flow. The PM10 concentration is
dominated by fine particles (53% of PM2.5 and 45% of PM1). The
high PM2.5/PM10 ratio indicates that the majority of PM10 particles
originate from re-suspension of road dust. The analysis of traffic flow
at the study site showed that 2W, 3W and 4W are having similar
diurnal trend as PM concentrations. This confirms that the 2W, 3W
and 4W are the main emission source contributing to ambient PM
concentration at SP road. The speed measurement at SP road showed
that the average speed of 2W, 3W, 4W, LCV and HCV are 38, 40,
38, 40 and 38 km/hr and 43, 41, 42, 40 and 41 km/hr respectively for
the weekdays and weekdays.
Abstract: Vehicular Ad-hoc Network (VANET) is taking more
attention in automotive industry due to the safety concern of human
lives on roads. Security is one of the safety aspects in VANET. To be
secure, network availability must be obtained at all times since
availability of the network is critically needed when a node sends any
life critical information to other nodes. However, it can be expected
that security attacks are likely to increase in the coming future due to
more and more wireless applications being developed and deployed
onto the well-known expose nature of the wireless medium. In this
respect, the network availability is exposed to many types of attacks.
In this paper, Denial of Service (DOS) attack on network availability
is presented and its severity level in VANET environment is
elaborated. A model to secure the VANET from the DOS attacks has
been developed and some possible solutions to overcome the attacks
have been discussed.
Abstract: The radius-of-curvature (ROC) defines the degree of
curvature along the centerline of a roadway whereby a travelling
vehicle must follow. Roadway designs must encompass ROC in
mitigating the cost of earthwork associated with construction while
also allowing vehicles to travel at maximum allowable design speeds.
Thus, a road will tend to follow natural topography where possible,
but curvature must also be optimized to permit fast, but safe vehicle
speeds. The more severe the curvature of the road, the slower the
permissible vehicle speed. For route planning, whether for urban
settings, emergency operations, or even parcel delivery, ROC is a
necessary attribute of road arcs for computing travel time.
It is extremely rare for a geo-spatial database to contain ROC. This
paper will present a procedure and mathematical algorithm to
calculate and assign ROC to a segment pair and/or polyline.
Abstract: For a spatiotemporal database management system,
I/O cost of queries and other operations is an important performance
criterion. In order to optimize this cost, an intense research on
designing robust index structures has been done in the past decade.
With these major considerations, there are still other design issues
that deserve addressing due to their direct impact on the I/O cost.
Having said this, an efficient buffer management strategy plays a key
role on reducing redundant disk access. In this paper, we proposed an
efficient buffer strategy for a spatiotemporal database index
structure, specifically indexing objects moving over a network of
roads. The proposed strategy, namely MONPAR, is based on the data
type (i.e. spatiotemporal data) and the structure of the index
structure. For the purpose of an experimental evaluation, we set up a
simulation environment that counts the number of disk accesses
while executing a number of spatiotemporal range-queries over the
index. We reiterated simulations with query sets with different
distributions, such as uniform query distribution and skewed query
distribution. Based on the comparison of our strategy with wellknown
page-replacement techniques, like LRU-based and Prioritybased
buffers, we conclude that MONPAR behaves better than its
competitors for small and medium size buffers under all used query-distributions.