Abstract: Foundation of tower crane serves to ensure stability
against vertical and horizontal forces. If foundation stress is not
sufficient, tower crane may be subject to overturning, shearing or
foundation settlement. Therefore, engineering review of stable support
is a highly critical part of foundation design. However, there are not
many professionals who can conduct engineering review of tower
crane foundation and, if any, they have information only on a small
number of cranes in which they have hands-on experience. It is also
customary to rely on empirical knowledge and tower crane renter-s
recommendations rather than designing foundation on the basis of
engineering knowledge. Therefore, a foundation design automation
system considering not only lifting conditions but also overturning
risk, shearing and vertical force may facilitate production of foolproof
foundation design for experts and enable even non-experts to utilize
professional knowledge that only experts can access now. This study
proposes Automatic Design Algorithm for the Tower Crane
Foundations considering load and horizontal force.
Abstract: In this paper, transversal vibration of buried pipelines
during loading induced by underground explosions is analyzed. The
pipeline is modeled as an infinite beam on an elastic foundation, so
that soil-structure interaction is considered by means of transverse
linear springs along the pipeline. The pipeline behavior is assumed to
be ideal elasto-plastic which an ultimate strain value limits the plastic
behavior. The blast loading is considered as a point load, considering
the affected length at some point of the pipeline, in which the
magnitude decreases exponentially with time. A closed-form solution
for the quasi-static problem is carried out for both elastic and elasticperfect
plastic behaviors of pipe materials. At the end, a comparative
study on steel and polyethylene pipes with different sizes buried in
various soil conditions, affected by a predefined underground
explosion is conducted, in which effect of each parameter is
discussed.
Abstract: The UK Government has emphasized the role of Local Authorities as a key player in its flagship residential energy efficiency strategies, by identifying and targeting areas for energy efficiency improvements. Residential energy consumption in England is characterized by significant geographical variation in energy demand, which makes centralized targeting of areas for energy efficiency intervention difficult. This paper draws on research which aims to understand how demographic, social, economic, urban form and climatic factors influence the geographical variations in English residential gas consumption. The paper reports the findings of a multiple regression model that shows how 64% of the geographical variation in residential gas consumption is accounted for by variations in these factors. Results from this study, after further refinement and validation, can be used by Local Authorities to identify areas within their boundaries that have higher than expected gas consumption, these may be prime targets for energy efficiency initiatives.
Abstract: Infrastructure investments are important in developing
countries, it will not only help to foster the economic growth of a
nation, but it will also act as a platform in which new forms of
partnership and collaboration can be developed mainly in East Asian
countries. Since the last two decades, many infrastructure projects
had been completed through build-operate-transfer (BOT) type of
procurement. The developments of BOT have attracted participation
of local and foreign private sector investor to secure funding and to
deliver projects on time, within the budget and to the required
specifications. Private sectors are preferred by the government in
East Asia to participate in BOT projects due to lack of public
funding. The finding has resulted that the private sector or promoter
of the BOT projects is exposed to multiple risks which have been
discussed in this paper. Effective risk management methods and
good managerial skills are required in ensuring the success of the
project. The review indicated that mitigation measures should be
employed by the promoter throughout the concession period and
support from the host government is also required in ensuring the
success of the BOT project.
Abstract: The article presents analysis results of maps of
expected subsidence in undermined areas for road repair
management. The analysis was done in the area of Karvina district in
the Czech Republic, including undermined areas with ongoing deep
mining activities or finished deep mining in years 2003 - 2009.
The article discusses the possibilities of local road maintenance
authorities to determine areas that will need most repairs in the future
with limited data available. Using the expected subsidence maps new
map of surface curvature was calculated. Combined with road maps
and historical data about repairs the result came for five main
categories of undermined areas, proving very simple tool for
management.
Abstract: Because of the reservoir effect, dynamic analysis of concrete dams is more involved than other common structures. This problem is mostly sourced by the differences between reservoir water, dam body and foundation material behaviors. To account for the reservoir effect in dynamic analysis of concrete gravity dams, two methods are generally employed. Eulerian method in reservoir modeling gives rise to a set of coupled equations, whereas in Lagrangian method, the same equations for dam and foundation structure are used. The Purpose of this paper is to evaluate and study possible advantages and disadvantages of both methods. Specifically, application of the above methods in the analysis of dam-foundationreservoir systems is leveraged to calculate the hydrodynamic pressure on dam faces. Within the frame work of dam- foundationreservoir systems, dam displacement under earthquake for various dimensions and characteristics are also studied. The results of both Lagrangian and Eulerian methods in effects of loading frequency, boundary condition and foundation elasticity modulus are quantitatively evaluated and compared. Our analyses show that each method has individual advantages and disadvantages. As such, in any particular case, one of the two methods may prove more suitable as presented in the results section of this study.
Abstract: Considering the merits and limitations of energy dissipation system, seismic isolation system and suspension system, a new earthquake resistant system is proposed and is demonstrated numerically through a frame-core structure. Base isolators and story isolators are installed in the proposed system. The former “isolates" the frame from the foundation and the latter “separates" the frame from the center core. Equations of motion are formulated to study the response of the proposed structural system to strong earthquake motion. As compared with the fixed-base building system, the proposed structural system shows substantial reduction on structural response.
Abstract: Natural pozzolan (NP) is one of the potential
prehistoric alternative binders in the construction industry. It has
been investigated as cement replacement in ordinary concrete by
several researchers for many purposes. Various supplementary
cementitious materials (SCMs) such as fly ash, limestone dust and
silica fume are widely used in the production of SCC; however,
limited studies to address the effect of NP on the properties of SCC
are documented. The current research is composed of different SCC
paste and concrete mixtures containing different replacement levels
of local NP as an alternative SCM. The effect of volume of paste
containing different amounts of local NP related to W/B ratio and
cement content on SCC fresh properties was assessed. The variations
in the fresh properties of SCC paste and concrete represented by
slump flow (flowability) and the flow rate were determined and
discussed. The results indicated that the flow properties of SCC paste
and concrete mixtures, at their optimized superplasticizer dosages,
were affected by the binder content of local NP and the total volume
fraction of SCC paste.
Abstract: This study is to evaluate the behavior of integral and
segmental specimens through static and cyclic tests. Integral
specimens were made with the same size to be compared with
segmental specimens that were made by connected precast members.
To evaluate its bending performance and serviceability, 1 integral and
3 segmental specimens were tested under static load. And 1 integral
and 2 segmental specimens were tested under cyclic load, respectively.
Different load ranges were considered in the cyclic tests to evaluate the
safety and serviceability. The test results showed that under static
loading, segmental specimens had about 94% of the integral
specimen's maximum moment, averagely. Under cyclic loading, the
segmental specimens showed that had enough safety in the range of
higher than service load and enough serviceability. In conclusion, the
maximum crack width (0.16mm) satisfied the allowable crack width
(0.30mm) in the range of service load.
Abstract: Researchers investigate arious strategies to develop composite beams and maximize the structural advantages. This study
attempted to conduct experiments and analysis of changes in the
neutral axis of positive moments of a Green Beam. Strain
compatibility analysis was used, and its efficiency was demonstrated
by comparing experimental and analytical values. In the comparison of
neutral axis, the difference between experimental and analytical values
was found to range from 8.8~26.2%. It was determined that strain
compatibility analysis can be useful for predicting the behaviors of
composite beams, with the ability to predict the behavior of not only
the elastic location of the composite member, but also of the plastic
location
Abstract: The paper deals with cartographic visualisation of
results of transport accessibility monitoring with the use of a semiautomated
method of unipolar anamorphosis, developed by the
authors in the GIS environment. The method is based on
transformation of distance in the map to values of a geographical
phenomenon. In the case of time accessibility it is based on
transformation of isochrones converted into the form of concentric
circles, taking into account selected topographic and thematic
elements in the map. The method is most suitable for analyses of
accessibility to or from a centre and for modelling its long-term
context.
The paper provides a detailed analysis of the procedures and
functionality of the method, discussing the issues of coordinates,
transformation, scale and visualisation. It also offers a discussion of
possible problems and inaccuracies. A practical application of the
method is illustrated by previous research results by the authors in
the filed of accessibility in Czechia.
Abstract: Structural redundancy is an interesting point in
seismic design of structures. Initially, the structural redundancy is
described as indeterminate degree of a system. Although many definitions are presented for redundancy in structures, recently the
definition of structural redundancy has been related to the configuration of structural system and the number of lateral load
transferring directions in the structure. The steel frames with infill walls are general systems in the constructing of usual residential buildings in some countries. It is
obviously declared that the performance of structures will be affected by adding masonry infill walls. In order to investigate the effect of
infill walls on the redundancy of the steel frame which constructed
with masonry walls, the components of redundancy including redundancy variation index, redundancy strength index and
redundancy response modification factor were extracted for the
frames with masonry infills. Several steel frames with typical storey number and various numbers of bays were designed and considered.
The redundancy of frames with and without infill walls was evaluated by proposed method. The results showed the presence of infill causes increase of redundancy.
Abstract: Cluster analysis is the name given to a diverse collection of techniques that can be used to classify objects (e.g. individuals, quadrats, species etc). While Kohonen's Self-Organizing Feature Map (SOFM) or Self-Organizing Map (SOM) networks have been successfully applied as a classification tool to various problem domains, including speech recognition, image data compression, image or character recognition, robot control and medical diagnosis, its potential as a robust substitute for clustering analysis remains relatively unresearched. SOM networks combine competitive learning with dimensionality reduction by smoothing the clusters with respect to an a priori grid and provide a powerful tool for data visualization. In this paper, SOM is used for creating a toroidal mapping of two-dimensional lattice to perform cluster analysis on results of a chemical analysis of wines produced in the same region in Italy but derived from three different cultivators, referred to as the “wine recognition data" located in the University of California-Irvine database. The results are encouraging and it is believed that SOM would make an appealing and powerful decision-support system tool for clustering tasks and for data visualization.
Abstract: In the paper a detailed analysis of the dynamic
response of a cooling tower shell to mining tremors originated from
two main regions of mining activity in Poland (Upper Silesian Coal
Basin and Legnica-Glogow Copper District) was presented. The
representative time histories registered in the both regions were used
as ground motion data in calculations of the dynamic response of the
structure. It was proved that the dynamic response of the shell is
strongly dependent not only on the level of vibration amplitudes but
on the dominant frequency range of the mining shock typical for the
mining region as well. Also a vertical component of vibrations
occurred to have considerable influence on the total dynamic
response of the shell. Finally, it turned out that non-uniformity of
kinematic excitation resulting from spatial variety of ground motion
plays a significant role in dynamic analysis of large-dimensional
shells under mining shocks.
Abstract: In this paper, a parametric experimental study for producing paving blocks using fine and coarse waste glass is presented. Some of the physical and mechanical properties of paving blocks having various levels of fine glass (FG) and coarse glass (CG) replacements with fine aggregate (FA) are investigated. The test results show that the replacement of FG by FA at level of 20% by weight has a significant effect on the compressive strength, flexural strength, splitting tensile strength and abrasion resistance of the paving blocks as compared with the control sample because of puzzolanic nature of FG. The compressive strength, flexural strength, splitting tensile strength and abrasion resistance of the paving block samples in the FG replacement level of 20% are 69%, 90%, 47% and 15 % higher as compared with the control sample respectively. It is reported in the earlier works the replacement of FG by FA at level of 20% by weight suppress the alkali-silica reaction (ASR) in the concrete. The test results show that the FG at level of 20% has a potential to be used in the production of paving blocks. The beneficial effect on these properties of CG replacement with FA is little as compared with FG.
Abstract: Loop detectors report traffic characteristics in real
time. They are at the core of traffic control process. Intuitively,
one would expect that as density of detection increases, so would
the quality of estimates derived from detector data. However, as
detector deployment increases, the associated operating and
maintenance cost increases. Thus, traffic agencies often need to
decide where to add new detectors and which detectors should
continue receiving maintenance, given their resource constraints.
This paper evaluates the effect of detector spacing on freeway
travel time estimation. A freeway section (Interstate-15) in Salt
Lake City metropolitan region is examined. The research reveals
that travel time accuracy does not necessarily deteriorate with
increased detector spacing. Rather, the actual location of detectors
has far greater influence on the quality of travel time estimates.
The study presents an innovative computational approach that
delivers optimal detector locations through a process that relies on
Genetic Algorithm formulation.
Abstract: The purpose of this study was to suggest some optimal
waterfront scales around small rivers by reviewing domestic and
foreign survey reports about concept and relevant systems of the
ecological cities, analyzing the data collected from a survey about
scales and facilities of waterfront green zones around small rivers. The
questionnaire survey was conducted by sampling professional
designers, developers, the citizens living in the GunpoSanbon district
covered by no river system and the citizens living in such districts
covered by a river system. The question items were about need, uses,
scale and facilities of waterfront in common, and about satisfaction
with waterfront in case of citizen groups. In short, most of the subjects
in 5 groups preferred 10~20 wide waterfront green zone. And it is
judged that the results of this study about uses and facilities of the
waterfront green zone and its scales would provide for some basic data
useful to future waterfront green zone and urban development plans.
Abstract: Effect of high temperature exposure on properties of cement mortar containing municipal solid waste incineration (MSWI) bottom ash as partial natural aggregate replacement is analyzed in the paper. The measurements of mechanical properties, bulk density, matrix density, total open porosity, sorption and desorption isotherms are done on samples exposed to the temperatures of 20°C to 1000°C. TGA analysis is performed as well. Finally, the studied samples are analyzed by IR spectroscopy in order to evaluate TGA data.
Abstract: In this paper a polymer electrolyte membrane (PEM)
fuel cell power system including burner, steam reformer, heat
exchanger and water heater has been considered to meet the
electrical, heating, cooling and domestic hot water loads of
residential building which in Tehran. The system uses natural gas as
fuel and works in CHP mode. Design and operating conditions of a
PEM fuel cell system is considered in this study. The energy
requirements of residential building and the number of fuel cell
stacks to meet them have been estimated. The method involved
exergy analysis and entropy generation thorough the months of the
year. Results show that all the energy needs of the building can be
met with 12 fuel cell stacks at a nominal capacity of 8.5 kW. Exergy
analysis of the CHP system shows that the increase in the ambient air
temperature from 1oC to 40oC, will have an increase of entropy
generation by 5.73%.Maximum entropy generates for 15 hour in 15th
of June and 15th of July is estimated to amount at 12624 (kW/K).
Entropy generation of this system through a year is estimated to
amount to 1004.54 GJ/k.year.
Abstract: Nonlinear finite element method and Serendipity eight
nodes element are used for determining of ground surface settlement
due to tunneling. Linear element with elastic behavior is used for
modeling of lining. Modified Generalized plasticity model with nonassociated
flow rule is applied for analysis of a tunnel in Sao Paulo –
Brazil. The tunnel had analyzed by Lades- model with 16 parameters.
In this work modified Generalized Plasticity is used with 10
parameters, also Mohr-Coulomb model is used to analysis the tunnel.
The results show good agreement with observed results of field data
by modified Generalized Plasticity model than other models. The
obtained result by Mohr-Coulomb model shows less settlement than
other model due to excavation.