bluuebunny/crossref_metadata_2025 huggingface dataset:
Load-deflection curve prediction of RC beams strengthened by externally bonded CFRP wraps and strips
Authors: Khan Asad-ur-Rehman  , Masood Fawwad
Published: February 2025

Increasing emphasis on serviceability and limit design has created a need for better understanding of the moment-curvature relationship of Reinforced Concrete (RC) beams cross-section. Non-linear characteristics of stress-strain curve of steel and concrete has been the major concern for many researchers, and accurate load versus deflection response can only be predicted by incorporating the same. In addition, Fibre Reinforced Polymers (FRP) has emerged as a viable solution to enhance the performance of RC beams both in terms of loads and deflection. An analytical tool has been developed in the present study to predict load-deflection and moment-curvature characteristics of RC beams (normal and strengthened by externally bonded FRP). The developed tool predicts complete load-deflection response of RC beams, with and without externally bonded CFRP system, using strain compatibility and force equilibrium technique with emphasis on cracked, yield and ultimate behaviour of such beams with shear span to depth (a/d) ratios varying from 2 to 6. Range of a/d ratios is selected to cover flexure and shear dominant loading regimes. Good agreement is found between predicted load-deflection curves with experimental data available in literature.
Cold-formed circular hollow sections under axial compression
Authors: Dundu Morgan  , Chabalala Vongani
Published: February 2025

Two series of experiments were carried out to investigate the behaviour of pinned-ended circular hollow section (CHS) columns, subjected to axial compressive load. A total of 30 columns were tested in this investigation; 20 columns in Series 1 and 10 columns in Series 2. The outside diameter-to-thickness ratio (d/t) and the slenderness ratio (KL/r) ranged from 29.7 to 46.4 and 20.8 to 82.2 for Series 1, respectively, and from 55.0 to 62.9 and 10.7 to 34.9 for Series 2, respectively. In general, Series 1 columns failed by overall flexural buckling and, whilst Series 2 columns failed by local ring-type buckling. The test strengths of the columns were compared with the strengths predicted by the South African design standard (SANS10162-1) and the European design standard (EN 1993-1-1).
Moisture transfer in three hemp concretes
Authors: Othmen Ines  , Poullain Philippe  , Leklou Nordine
Published: February 2025

The immense stress on the world's environment means that measures must be taken today to safeguard natural resources for tomorrow. This is the challenge the construction industry faces. For that, recent research has found a solution in the use of bio-based materials. Hemp has renewed popularity due to its potential as a sustainable, eco-friendly resource. It's fast-growing, renewable, biodegradable and recyclable. The study investigates the measurement of the capillary absorption coefficient for three different hemp concretes. This coefficient will focus on the hydrophilic nature of these plant-derived particles and consequentely the risk of mould growth.
Precast concrete fencing units in low cost domestic housing in South Africa – a case study
Authors: Mlasi Stella M.
Published: February 2025

The rectangular flat concrete precast panels which are widely used as building blocks in fencing construction, have been introduced in the design and construction of low cost domestic housing. The use of masonry units has been the main option in the design and construction of domestic houses in South Africa. However, the use of precast concrete fencing panels, as an alternative, in domestic housing construction is spreading and undergoing improvement.
Performance measurement of quality of houses: development of a building quality index for houses
Authors: Mahachi Jeffrey
Published: February 2025

The risk of structural failures of residential housing in South Africa is determined by the effectiveness of implementation of the relevant technical regulations. This risk has to be managed proactively in order to ensure consistent quality of the product. However, internationally, very little has been done to quantify the quality of a housing product. In this paper, a quality assessment system is presented, referred to as the Building Quality Index for Houses (BQIH). The quality assessment is carried out by measuring the constructed works against the workmanship standards and specifications. The measurements are comprehensive, straight-forward, consistent and effective. Furthermore, the assessments are carried out systematically and within reasonable cost and time. Of particular importance in the development of this system is the research and involvement in Conquas 21, the internationally acknowledged quality system for commercial buildings which was developed by CIDB in Singapore. A study into the applicability of Conquas 21into the South African home construction market was carried out and the information which was obtained formed the basis for developing the BQIH.
Blended cement utilizing ceramic wall tiles waste
Authors: Sadek Dina M.  , Amin Sh.K.  , Youssef N.F.
Published: February 2025

In order to reduce the footprint over the environment, regarding the great energy consumption required to produce cement, it was allowed in the International, European and Egyptian standards to produce the blended cement known as CEMII. This work could successfully utilize the fired ceramic wall tiles waste rejected in industry to partially replace cement up to 35% by weight to produce one of the allowed types of CEMII, depending on the fact that Egyptian standards of ceramic wall tiles allows only the 1stgrade to be delivered to the market. The obtained blended cement was found to be in good conformity to the standards.
Nanoparticle modified concrete materials: opportunities, challenges and prosperities
Authors: Wang Kejin  , Lomboy Gilson R.
Published: February 2025

Research and applications of nanoparticles in concrete materials are rapidly increasing because fundamental properties of concrete (such as rheology, strength, transport properties, fracture behavior, etc.) are strongly influenced by the material properties at the nanoscale. Use of nanomaterials in concrete can also enhance sustainability and reduce negative environmental impact through reduction in cement use, energy and natural material consumptions during production and service. In this paper, the needs and opportunities of use of nanoparticle modified concrete are highlighted. The challenges in nanoparticle processing (such as dispersion and stabilization) are addressed. Recent developments in characterization methods (such as Raman spectroscopy, nanoindentation, modulus mapping, peak-force quantitative nanomechanical mapping and atomic force microscopy) are reviewed. Effects of nanoparticles (such as nanosilica, nanolimestone and nanoclay) on concrete rheology, hydration, microstructure development, mechanical properties, and durability are discussed.
Utilization of ceramic wastes as replacement of portland cements
Authors: Rahhal Viviana  , Irassar Edgardo  , Castellano Cristina  , Pavlík Zbyšek  , Černý Robert
Published: February 2025

The possible applicability of ceramic waste as partial replacement of Portland cement was studied. For this purpose, two ceramic wastes and two Portland cements of different countries (Argentine and Czech Republic) were analysed. After characterization of the materials used (chemical and mineralogical composition and specific surface), the effect of ceramic waste replacement (8, 16, 24, 32 and 40 % by mass) was analyzed. The pozzolanic activity, the heat released rate and the hydration products were determined at 2, 7 and 28 days. Results show that ceramic wastes have pozzolanic activity with both portland cements. At early age, the dilution effect governs the properties and finally the pozzolanic reaction improves the performance of blended cements.
Assessing the effect of procurement source of scoria rocks on the pozzolanic properties of the cementitious system
Authors: Fares Galal  , Alhozaimy A.  , Al-Negheimish A.  , Alawad Omer A.
Published: February 2025

Arabian Peninsula possesses large deposits of scoria rocks (SR) of different grain sizes around pyroclastic volcanic cones along the Arabian shield. SR grains are commonly used as lightweight aggregates in the production of lightweight concrete. Mineral admixtures from local resources are unavailable in the Arabian Peninsula; therefore, searching for local alternatives becomes a necessity. In this study, SR is proposed for the use as natural pozzolan. Three SR samples procured from different sources, defined by GPS international coordinates, were characterized using stereomicroscope and FESEM techniques. SR samples were then ground for a definite time of 120 min. The SR powders obtained were investigated using laser particle size, X-ray diffraction analysis (XRD), X-ray fluorescence (XRF) and field emission scanning electron microscope -energy dispersive X-ray spectroscopy (FESEM-EDS) analyses. The strength activity indices of mortars with water-to-binder (W/B) ratio of 0.5 and a replacement level of 20% ground SR powders at curing ages of 28 and 180 days were determined. The strength activity index was found to depend on SR physico-chemical properties. FESEM analysis has shown how SR particles react in the cementitious system. It is concluded that SR particles react according to the chemical and physical nature of their constituting phases (silicic, aluminic and ferric). The particle size is not the only parameter that controls the pozzolanic activity of SR powders. It is verified that SR grain surface contamination greatly affects the microstructure of the cementitious system. SR samples are found to provide different latent pozzolanic properties. SR3 powder has shown the best potential for use as an alternative supplementary cementitious material in the Arabian Peninsula.
Study of particle packing in self-consolidating mortar systems
Authors: Rizwan Syed Ali  , uz Zaman Qamar  , Bier Thomas A.
Published: February 2025

This paper reports the results of self-consolidating cementitious systems using Dinger & Funk (D &F) particle packing model which is a refinement of Anderson & Andreasen model (A & A) in the sense that it contains both minimum and maximum particle sizes in the expression for cumulative percent finer than a given size “d” (CPFT-percent passing a given sieve size “d”). D & F packing model seems to be fairly applicable to the particle packing in cementitious systems using fine mineral admixtures. Better particle packing results in reducing voids and hence total paste volume requirement of self-compacting cementitious systems is also reduced translating into improved economy, durability and volume stability. Several formulations based on such models were designed and tested. Flow of self-consolidating mortar (SCM) systems was found to be depending on particle size distribution of the matrix. The self-consolidating mortar system incorporating mineral admixtures showed better packing at distribution modulus ‘q’ = 0.205 and displayed improvement in strengths. It appears that with the additions of fine powders the value of ‘q’ reduces.
A new structural sand lightweight concrete mix design
Authors: Bogas J. Alexandre  , Gomes M. Glória  , Real Sofia  , Pontes Jorge
Published: February 2025

A simplified design method is proposed for structural Lightweight aggregate concrete (SLWAC) made with natural sand. The major advantages of the proposed method are that it is easy to apply and it can be generalized to any type of lightweight aggregate (LWA). For this, three additional design parameters are needed: the strength of LWA in concrete; the limit strength; the SLWAC potential strength. At most, two experimental mixtures are needed to determine these parameters. A biphasic model to estimate the strength of SLWAC is evaluated and high correlations are obtained. The good performance of the suggested method is demonstrated by the comparison with experimental results reported by the authors.
The effect of different PPC binders, partially replaced by fly ash properties, on self-compacting concrete
Authors: Almuwbber Omar  , Haldenwang Rainer  , Masalova Irina
Published: February 2025

The effect of different CEM I 52.5N cements produced at different factories on Self-Compacting Concrete (SCC) is currently not well understood. The effect of four cements tested and one type of superplasticiser (SP) and partially replaced with two types of fly ashon an SCC mix were studied. Mix design and tests were done according to the European Specification and Guidelines for Self Compacting Concrete (2005). The cementsreacted differently with addition of the SPs and partial replacement of fly ash. Although the differences can be distinguished from the SCC tests, it is not yet understood what causes these differences.
Geopolymer concrete: a practical approach
Authors: Attwell Cyril
Published: February 2025

High production costs of concrete in combination with the high CO2footprint of cement has instigated the research, development and application of concrete utilizing by-products and wastes as partial or entire binder replacements. The literature research progressed through the myriad of definitions and theses available to define two distinct paths of activation, notably alkali- and acid-activations. The alkali-activated path was chosen as the operating risks with alkali materials within the construction industry are known. Experimental work progressed in the laboratory using this base concept to achieve a predictable material with properties similar to both resin and concrete systems depending on the balance of chemistry. The experimentally-defined chemical system has been applied in trials for concrete slabs to study the properties in dry and wet plastic states and their respective hardened properties. The hardened properties tested include shrinkage, durability, compressive and flexural strengths under different curing regimes. Plastic properties were reviewed through the placing, consolidation and finishing of the products. Differences in consolidation and finishing were established with wet-plastic applications. The majority of hardened state properties were improved except for a marginal decrease of flexural strength. Due to the benefits in the plastic and hardened state of the geopolymer concrete, further applications on several sites with improvements to the chemical process are being considered to evaluate the viability of replacing conventional portland cement concrete with the geopolymer concrete on a structural basis.
The development of sustainable geopolymer mortar from fly ash-palm oil fuel ash based binder and manufactured sand
Authors: Bashar Iftekhair Ibnul  , Alengaram Ubagaram Johnson  , Jumaat Mohd Zamin  , Islam Azizul
Published: February 2025

The use of alternative binder from industrial waste product, namely palm oil fuel ash (POFA) to replace conventional fly ash (FA) and the effect on the use of processed quarry waste, alternatively known as manufactured sand (M-sand) as fine aggregate replacement for conventional mining sand (N-sand) in the development of compressive strength of POFA-FA based geopolymer mortar is investigated. The variable investigated includes the quantities of replacement levels of M-sand with N-sand. The alkaline solution, water, POFA/FA ratio and curing condition remained constant. The results show that the silica rich POFA and FA increased the rate of strength development of the mortar and an average of 76% of the 28-day compressive strength was found at the age of 3-day. Based on the compressive strength, it can be seen that the use of alternative addition of 100% M-sand shows that comparable strength as that of mortar prepared with mixes of 100% N-sand. The particle size of fine aggregates play significant role in the strength development due to the filling and packing ability. The use of industrial waste materials such as POFA-FA and M-sand as binders and fine aggregate, respectively could be viable alternative to conventional concrete that could lead to sustainable geopolymer material.
Simple criteria for evaluating sulphate attack in concrete
Authors: Ekolu Stephen
Published: February 2025

This paper attempts to analyse results from the standard test methods employed for sulphate attack and evaluates their correlations, consistency and contrasts, as well as physical observations. Data from expansions and mass change of 25 x 25 x 285 mm mortar prisms and 75 x 75 x 285 mm concrete prisms were used. Mortar mixtures consisted of 1: 2.25: 0.5 cement to sand to water while concrete mixtures were of water-cementitious ratio (w/cm) of 0.45, 0.50, 0.65. Mixtures were made using CEM I 42.5N with or without 30, 50, 70% ground granulated blast furnace slag (GGBS) and stored in sodium sulphate solutions of 28 g/L and 50 g/L as SO4. Results show that ASTM C 1012 mortar expansion criteria of 0.10% corresponds to 1.2% mass gain. Similarly, concrete prism expansion criteria of 0.05% is equivalent to 0.75% mass gain. It is proposed that in the absence of expansion monitoring, the use of mass gain criteria of 1.2% mass in mortar prisms or 0.75% in concrete prisms may be sufficient for evaluating sulphate attack.
Green road construction using discarded materials: a holistic overview from the Middle East
Authors: Taha Ramzi
Published: February 2025

Various wastes and by-product materials are generated in the Middle East including reclaimed asphalt pavement (RAP) aggregate, demolition concrete, excavation waste, steel and aluminum slags, cement by-pass dust (CBPD), copper slag, petroleum-contaminated soils (PCS), waste tires, incinerator ash, and others. Recycling of such materials for road construction is not practiced. Research data and field studies on the potential use of selected materials in road construction applications are limited. This paper presents an overview of the different waste materials generated in many countries in the Middle East, their potential applications in road construction and the impediments to recycling initiatives. Representative results of several laboratory studies on the use of PCS in asphalt concrete mixtures; the utilization of CBPD in soil stabilization; and the recycling of RAP aggregates in road bases and sub-bases will be presented. The Laboratory data indicated that it is feasible to partially reuse some of these materials in road construction provided that economic incentives and environmental concerns are taken into consideration.
A model of Air Transport Passenger Incidents and Rights
Authors: Rodríguez-Doncel Víctor  , Santos Cristiana  , Casanovas Pompeu
Published: February 2025

This paper describes a representation of the legal framework in the air transport passenger's rights domain and the foremost incidents that trigger the top of consumer complaints ranking in the EU. It comprises the development of a small network of three ontologies, formalisation of scenarios, specification of properties and identification of relations. The approach is illustrated by means of a case study based in the context of a real life cancelled flight incident. This is part of an intended support-system that aims to provide both consumers and companies with relevant legal information to enhance the decision-making process.
Finding Acceptable Trade-off between Rate and Distortion in Multiple Description Coding based on Zero Padding
Authors: Chang Rong-Hua  , Su Chieh-Wei  , Lin Chow-Sing
Published: February 2025

In the studies related to Multiple Description Coding (MDC), applying zero padding not only improves the spatial correlation between the descriptions but also increases the size. However, as we pad more zeros, the spatial correlation does not improves linearly. Therefore, the distortion is not reduced as the same amount as the size increases. In this paper we focus on how to efficiently find an acceptable trade-off between the number of padded zeros and the increase of distortion. Based on a MDC method named “Multiple Description Coding with Zero Padding based on spatial Quincunx distribution (QZP-MDC)”, in this paper we propose a distortion estimation, which is “Standard Deviation for Distortion Estimation (STD-DE)” to efficiently calculate the distortion with specific padding direction and the number of padded zeros. To search for the acceptable the number of padded zeros, we design two search methods, Naïve Search and Best Division Search, based on the proposed rate-distortion trade-off indicator. Our experiment results show that errors of distortion estimation by STD-DE are all less than 2%, and the executing times by best division search is about twice faster more than those of naïve search for 11 test sequences. To summarize our work, we confirm that the best division search on STD-DE can find the acceptable trade-off between rate and distortion in low computational complexity.
A Solution to Improve Web Application Performance
Authors: Huang Yi-Ming  , Kuo Ching-Wen  , Tsai Ching-Tsorng
Published: February 2025

A new solution for rich Internet application design is proposed. By archiving and compressing page resources to reduce web requests, the proposed architecture can solve page view preparation performance issue. In our experiments, the proposed solution can improve the performance by as much as 55%.
Design of Proxy Signature Schemes Using Self-Certified Public Keys from Pairings
Authors: Hsu Chien-Lung  , Chuang Yu-Hao  , Tsai Pei-Ling
Published: February 2025

This paper designs a system model of flexible proxy signature schemes and introduces some realizations for this model from pairings. The proxy signature scheme allows an original signer to delegate his signing authority to a designated person called proxy signer. With that the proxy signer can sign a message through anonymous or non-anonymous methods alternatively, which is depending on the different demand as well as the property of a message. For these reasons, we introduce message recovery and appendix approaches to satisfy the applications of short message and long message, respectively. From the perspective of any verifier, checking the validity of the proxy signature can be accomplished through the verification of the public key in a logically single step, which is advantageous in communication overhead. Finally, we analyze the proposed proxy signature schemes from several security points of view.
On Reversible Data Hiding Schemes for JPEG Images from the Modified Quantization Table
Authors: Chang Jen-Chun  , Lee Chen-Hsuan  , Wu Hsin-Lung
Published: February 2025

In this paper, we construct a reversible data hiding scheme for JPEG images generated from the modified quantization table proposed previously by Chang et al. in Information Sciences, 2002. Previously, the known data hiding scheme for this class of JPEG images is the high-capacity scheme proposed by Chang et al. However, their scheme is irreversible. We propose a reversible version for this class of JPEG images. Experimental results show that our proposed scheme outperforms other schemes on embedding capacity and stego-image quality for most test images.
Reintroducing the intrinsic self healing properties in reclaimed asphalt
Authors: Qiu Jian  , Schlangen Erik  , van de Ven Martin  , Scarpas Tom  , Shirazi Morteza
Published: February 2025

In the Netherlands, 4 million tons of reclaimed asphalt (RA) were produced per year according to the European Asphalt Pavement Association (EAPA). Over 90% of the total reclaimed asphalt was reused into new asphalt constructions. However, for the most used new porous asphalt surface layer on the Dutch motorway system, the allowable RA percentage is only 25%. With the increasing needs of high percentage (up to 100%) and high performance (surface-to-surface) recycling due to both economic and environmental issues, it is of high importance to investigate the possibility to recycle the high quality surface layer (porous asphalt, stone mastic asphalt, etc.) RA back to the surface layers. The ultimate goal is to realize a 100% surface-to-surface asphalt recycling. In this research, a high performance material system (namely, rejuvenator) was developed to regenerate the flexibility and self-healing capability into the RA, which are the most important elements guaranteeing the long service life of asphalt mixtures. Based on the knowledge on the chemical/mechanical responses on the rejuvenated and re-aged bituminous materials, together with the in-situ diffusion analysis with Computer Tomography (CT) scan and Fourier Transform Infrared Spectroscopy (FTIR) measurements, a rejuvenator with excellent rejuvenating capability was developed. To evaluate the rejuvenating capability of the developed rejuvenator in a real application, a trial production was performed with a highly ecologic asphalt recycling (HERA) system by our project partners with high RA percentages, and a trial section was then constructed in 2014 with success. Experiments carried out on the cores drilled from the section indicated good performance. Now it is important to monitor the test section over time in order to gather more useful real service data. Based on the laboratory and field trial section results, it is expected that the developed rejuvenating product can guarantee a high performance surface-to-surface recycling.
Modelling crack propagation in particle-dispersed self healing thermal barrier coatings
Authors: Ponnusami Sathiskumar A.  , Turteltaub Sergio  , Zhang Xun  , Xiao Ping
Published: February 2025

A computational study to identify the critical material properties and optimal spatial distribution of capsules containing a reactive healing agent for a brittle (ceramic) matrix is presented. The study focusses on the so called self-healing thermal barrier coating (TBC) system in which suitable healing particles are dispersed in the coating layer with the goal of improving the lifetime of the TBC systems. For successful triggering of the healing process, a primary requirement is that the initiated micro cracks in the TBC matrix should get attracted to the healing particles and, in addition, the cracks should open the particles. Consequently, the interaction between a crack and a healing particle becomes the crucial issue governing the behavior of such systems. The key objective of this chapter is to identify and assess the critical parameters that control the fracture process in the healing particle-matrix system. To achieve this, cohesive element-based finite element fracture analyses were conducted on two different particle/matrix systems, namely an idealized single healing particle-matrix system and a microstructure based system with a random distribution of healing particles in the matrix. The effect of mismatch in elastic and fracture properties between the healing particle and the matrix and the effect of particle/matrix interface properties on the crack path were examined quantitatively. Optimal configurations in terms of mechanical properties of the particles and the particle/matrix interface relative to the matrix material (fracture strength, toughness) to trigger the healing reaction were identified.
Stimulated healing of a proton exchange membrane fuel cell catalysts
Authors: Latsuzbaia Roman  , Negro Emanuela  , Koper Ger
Published: February 2025

We propose a novel idea of in situ fuel cell catalyst stimulated-healing, which involves in situ dissolution of the catalyst and then redeposition on the same catalyst support. We study the possibilities of rapid fuel cell Pt catalyst dissolution procedures that are non-corrosive to other fuel cell components. As a subsequent step, we studied possibilities to synthesize Pt nanoparticles in situ for the redeposition of the dissolved Pt.
Water Quality and Flux of Bagmati River within Kathmandu Valley, Nepal
Authors: Bhatt Maya P.
Published: February 2025

Water quality degradation is a serious environmental problem in Nepal especially in urbanized basins. Water sampling was carried out along the heavily urbanized Bagmati drainage network within Kathmandu valley during 2010–2011 in order to evaluate the controlling factors of chemical parameters and to estimate the transport of chemicals from different positions of the landscape. The direct inputs of municipal solid wastes associated with high population density appeared as a prime controlling factor for the variation in chemical parameters and their fluxes. Most of the chemical parameters appeared to increase their concentration with distance downstream. The silicon concentration was much higher than the large river systems of the world and world average probably due to high temperature and high population density. The DOC and TDN concentrations appeared much higher than other pristine river systems in the world. The C:N and N:P ratios were found in the range 0.5–2.6 and 0.3–2.0 respectively along the drainage network. Bisiallitization type of weathering appeared dominantly taking place throughout the basin. The 19.8 and 33.6 tons km−2yr−1of dissolved organic carbon (DOC) and total dissolved nitrogen (TDN) were respectively transported from the outlet point. The cationic denudation rates were 106.4 and 19.6 tons km−2yr−1at the outlet of Bagmati within Kathmandu valley and at the headwater area respectively. The apparent weathering rate appeared five times higher than the actual weathering rate in a heavily urbanized Bagmati basin due to high population density.
From Print to Ebooks: A Hybrid Publishing Toolkit for the Arts
Authors: Digital Publishing Toolkit Collective  , Riphagen M.  , Rasch M.  , Cramer F.
Published: February 2025

This article is an excerpt of the outcome of a two-year research and development project on hybrid publishing. The DPT Collective [1] developed a Toolkit which consists of the publication From Print to Ebooks: A Hybrid Publishing Toolkit for the Arts [2] and an online software kit [3] – which is meant for publishers who publish visually oriented books in mostly smaller print runs. This Toolkit focuses particularly (but not exclusively) on EPUB3 as an electronic publication format, and on Markdown [4] as a word processing format. The recommendations stem from our practical experience in collaborating on electronic publication projects with four Dutch art, design and research publishers: BISPublishers, Valiz, nai010 uitgevers and the Institute of Network Cultures.
Determination of Spatial Variability in d
Authors: de Visser M.M.  , Kanning W.  , Koopmans R.  , Niemeijer J.
Published: February 2025

Research to the failure mechanism piping (internal erosion) in the Netherlands shows, that the dikes (levees) require costly berms to meet the required safety standards. According to the piping-formula, the d70(70%-quantile of the grain size distribution) is an important parameter in the resistance against piping. Therefore a better insight in the d70variation in the naturally deposited sand layers beneath dikes is of great importance. High density site measurements (5x5 meters spacing) give insight in local heterogeneity of the d70grain size and the implications for representative design values. Three test sites were developed at locations with distinct geomorphological deposits. The spatial variability in the d70can be large, despite the large amount of data at a very dense measurement grid and there is no obvious spatial correlation in the measurements. The sites have a similar or larger coefficient of variation than the much sparser regional datasets that are normally used to derive the representative d70. Current regulations prescribe the characteristic (5% lower bound) value as the design parameter in the piping formula. Considering the large variation in d70values this approach may not be appropriate. Given the influence of the d70on the dike dimensions, and thus the investment costs, establishing a method for determining a plausible d70value is important. We recommend developing more sites at distinct geomorphological deposits to gain more insight in the spatial variability in grain size distribution and data to improve methods on how to determine representative design values with matching site sampling requirements.
Limit State Imprecise Probabilistic Analysis in Geotechnical Engineering
Authors: Marques Sónia H.  , Beer Michael  , Gomes António T.  , Henriques António A.
Published: February 2025

The treatment of imprecision attracted continuous interest since the origin of probability as the science of uncertainty. As a matter of fact, probability has been developed to deal with uncertainty and the first argument supporting precise rather than imprecise probability counts on the nature of ordinary measurements. Starting from only a few papers wherein imprecise probability has been explored as a marginal alternative to precise probability, a number of devoted works appeared with intensified frequency in the second half of the 20thcentury. From first developments, imprecise probability emerged in the field of engineering by different approaches. The key feature consists in the identification of probability bounds for scenarios of interest with extended application in model validation, provided the ingredients for a systematic investigation of sensitivities. In this way, regardless of the increased interest in probabilistic methods within the geotechnical engineering community, unresolved issues may comprehend a discrepancy in reliability studies regarding the frequency of failure whereas enough tests are very seldom available for a definite choice of the best statistical model. A mixed approach that admits imprecise information as well as probabilistic information is therefore desirable. In this paper the conventional probabilistic approach to uncertainty is extended to include imprecise information in the form of intervals. For demonstration, results are provided for a strip spread foundation designed by the Eurocode 7 methodology, wherein the shear strength parameters of the foundation soil are implemented as intervals and then combined with other uncertain parameters in the form of random variables under dependence.
A Procedure to Determine Resistance Factors for a Newly Developed Rotation Steel Pile
Authors: Otake Yu  , Honjo Yusuke  , Kusano Tomohiro
Published: February 2025

The aim of this study is to establish a procedure to determine resistance factors for newly developed pile products through an example of the rotational intrusion steel pile (RI pile). RI pile is a newly developed steel pile product which has the vane type tip structure to resist reliably against vertical load and to intrude easily by rotating itself. Moreover, the RI pile is environment-friendly, i.e. reduce waste soil and less construction noise, because of the rotating intrusion method. The construction can be done with the small pile driving equipment and the pile can be reliably founded into the bearing ground by monitoring and controlling the torque value during installation. For these reasons, the RI-pile is expected to have the superior bearing capacity against vertical loads. However, the RI-pile has not been adopted in many construction projects yet because the current design method requires applying the same safety factor neglecting the level of the uncertainty of each pile type. In this study, 64 loading test data are gathered to quantify the model error of the RI-pile assisted by Public Works Research Institute (PWRI). Then, Reliability analysis is conducted based on our proposed reliability analysis scheme (GRASP) to specify the reliability level of the current design. Furthermore, the partial factor updating procedure according to the newly developed the RI pile is formulated based on the design value method. From the results, the partial factor is determined and applied to compare the RI steel pile to the traditional piles, i.e. cast in pile and driven steel pile. The difference in construction cost among the three piles has become less, and the RI pile is less expensive when the rate of the pile tip resistance is high.
Limit-State Design of a Steel Storage Tank Foundation on a Crushed Rock Ring Based on Proven Soil Strength
Authors: Reinders K.J.  , Schoenmaker B.  , Nohl W.A.
Published: February 2025

New vertical steel storage tanks founded on a shallow foundation of a crushed rock ring are planned at the same location of former storage tanks. The dimensions, loads and foundation of the new tanks are identical to the old tanks which were erected 40 years ago and demolished a few years ago. Despite the fact that the new tanks are identical to the old tanks, the stability calculation for the foundation of the new storage tanks did not fulfill the requirements of the present Eurocode 7-1. To ensure sufficient stability, additional measures like soil improvement are necessary. This is due to the fact that safety levels have much increased in the last 40 years. In order to optimize the design, it was decided to recalculate the stability using the code for existing structures “NEN 8707”, which is currently being developed. According to NEN 8707 it is allowed to use a lower value for the reliability index β for existing structures compared to new structures, because of proven strength. Thus, lower partial load and material factors can be applied. These calculations with the adjusted partial factors resulted in a sufficient overall safety factor for the ultimate limit state for the hydro-test phase and the operational phase. Thus, using NEN8707, the tanks can be built on a crushed rock ring foundation without an expensive soil improvement.
A Preliminary Study on the Comprehensive Evaluation of the Disaster Prevention System of Large Urban Underground Space
Authors: Xu Haiyong  , Yu Mingjian  , Huang Hongwei  , Fan Yiqun
Published: February 2025

The original urban planning can never meet the requirements of the rapid development and the increasing population in big cities in China. The best way to solve this problem is to develop the underground space (including tunnels). With the exhaustion and saturation of the shallow underground space, the development of urban area is more and more relying on the excavation of deep underground space. Nowadays, the advanced technology of high strength concrete, excavation method in soft soil and ground deformation control make it possible to build underground space with a larger scale, span length and depth. The common disasters and hazards that large urban underground space faces are the same as that of ordinary underground space, but considering the damage and the rescue difficulties, more attention should be paid to the influence of disasters on large underground space. The study and research on the evaluation of the disaster prevention system of underground space still have not raised enough attention yet. The Comprehensive Evaluation of the disaster prevention system is set up based on the study of the characteristics of large underground space itself and disaster effects. The evaluation of the prevention of fire, flood, earthquake and attack are discussed. This is a preliminary study of the future disaster management and emergency rescue of urban underground space.
Geotechnical Ultimate Limit State Design Using Finite Elements
Authors: Brinkgreve Ronald B.J.  , Post Mark
Published: February 2025

Displacement-based finite element calculations are primarily used for serviceability limit state (SLS) analysis, but the finite element method also offers possibilities for ultimate limit state (ULS) design in geotechnical engineering. The combined use of SLS and ULS calculations with partial safety factors according to the different design approaches in the Eurocode 7 can be time-consuming and prone to error. In this paper a Design Approaches facility is presented for an efficient use of partial safety factors in a finite element environment. In addition to a description of the methods used in this facility, an example is elaborated involving the geotechnical design of a sheet-pile wall supported excavation using different design approaches.
Safety Assessment Method of Flood Defences for Flow Sliding
Authors: van der Krogt M.G.  , van den Ham G.A.  , Kok M.
Published: February 2025

Flow sliding of submerged slopes in front of dikes affects flood safety. The occurrence of flow sliding may result, sometimes with delay, in a failure mode and consequent flooding. The current safety assessment method for flow sliding does not consider the interaction between flow sliding and failure modes. Therefore it is unclear whether the safety assessment method is sufficiently safe or too conservative. This paper presents a method to derive a simple safety assessment and design rule based on a number of advanced probabilistic analyses made for four Dutch cases, in which both flow sliding and the relevant direct failure modes have been incorporated. Two methods for the safety assessment of flow sliding are presented: as separate failure mode and coupled to direct failure modes.
Continuous River Levee Safety Assessment based on a Reliability Analysis
Authors: Otake Yu  , Honjo Yusuke  , Hiramatsu Yuuichi  , Lee Keita  , Kodaka Takeshi
Published: February 2025

A design scheme is proposed to evaluate the safety of continuous linear structure i.e. river levee. The scheme is developed to establish a procedure to continuously evaluate the stability failure of embankment during flood runoff by seepage, and to identify locations for reinforcement of river levee. A 20km stretch of a fairly large river running through one of the major cities in Japan is chosen for a case study. First all the information available for this river levee for the both side of river have been collected and complied. The data include river levee configurations for every 200m, all the soil investigation results done in the past and the results of levee safety inspection by MLIT. The strength parameters of the embankment and the foundation are obtained from about 50 triaxial test results (CUbar). The permeability coefficient is estimated from about 300 grain size distribution and 15 permeability test results. The configurations of the levee sections are analyzed, and the ranges of various dimensions, such as slope inclinations, crown width, height of retaining wall at edge of slope etc., are obtained. Based on these information, detailed seepage and stability analyses for the possible dimensions of levee sections and material properties are carried out to get the response function (RS) for the safety assessment. Based on this information, the response surface (RS) for the river levee is developed. In developing RS, the experimental design technique is applied for efficiency. MCS is applied to evaluate the failure probability of the levee based on the parameters obtained from the all the analyses explained above for every 200m interval along the levee because all the configuration dimensions of the levee is available at these sections. Results of MCS are presented along the levee, which immediately shows less safe sections.
Utilization of EPS Geofoam for Bridge Approach Structure on Soft Bangkok Clay
Authors: Vardhanabhuti Barames  , Chantawarangul Korchoke  , Seawsirikul Sorasak
Published: February 2025

Differential settlement along bridge approach structure is one of the continuing problems for highway construction in Bangkok and its vicinities due to soft ground foundation. To minimize the differential settlement and serviceability failure, an approach slap on piles with varies pile length is a current geotechnical engineering practice for the bridge approach structure construction. Instead of ground reinforcement by piles as a bearing unit, EPS Geofoam could be utilized as a lightweight embankment along the bridge approach, and could be an alternative solution to reduce differential settlement problem and repair works in the city area in which fast construction time is the main requirement. Two case studies of bridge approach structure were investigated, and different types of bridge approach structure, including approach slap on pile with different pile length distributions, and application of EPS, were evaluated in terms of engineering performance and construction and maintenance cost, and time. The results show that utilizing domestic EPS Geofoam for bridge approach structure could increase the construction cost by 20 to 30%, however, it could save construction period and could reduce the long-term maintenance cost.
Soil Displacement Induced Laterally Loaded Piles Test Embankments Bloemendalerpolder – GeoImpuls Program
Authors: Schadee L.W.  , Hoefsloot F.J.M.
Published: February 2025

In the Bloemendalerpolder two test embankments were constructed in 2010 to study the long term behaviour of embankments on very soft soils with respect to settlement and lateral pile loading resulting from horizontal soil deformations. A detailed description of the test embankments, performed soil investigation, laboratory tests and instrumentation is given in an accompanying paper. This paper provides a brief description of both test embankments consisting of sandfill with a height of 3.0 m and a ground area 26 x 36 m2with slopes 1:2. At one embankment – overlying 5.7 m of peat/clay – wick drains are installed at a triangular spacing of 1.0 m. The second embankment – overlying 4.0 m of peat/clay – is not provided with any additional drainage accelerating measures. In each embankment two steel H-beam piles have been installed, one located at the crest of the slope and one 4 m from the crest. Both piles have been installed 3 weeks after completion of the final fill increment. The pile bending stiffness represents a prefabricated concrete pile square 0.26 m. The piles were equipped with a steel square guiding tube to perform inclinometer measurements. Inclinometer readings were performed at regular time intervals, each reading at depth intervals of 0.1 m. The small interval was selected to improve interpretation with respect to pile curvature and therefore the derivation of pile bending moments. Although horizontal soil deformations after pile installation are significant the resulting bending moments remain limited.
Geo Risk Management Results for a Public Client Organization
Authors: Van Staveren Martin  , Litjens Paul  , Heerema Jan Jaap
Published: February 2025

Rijkswaterstaat is the executive agency of the Ministry of Infrastructure and the Environment, responsible for development and maintenance of the Dutch main road network, main waterway network and main water systems. Managing and realizing these networks, not only within time, budget, safety margins and quality standards, but also with a minimum of public inconvenience during construction, are key success factors. In this respect subsoil conditions imply great risks and therefore are of major importance. For these reasons Rijkswaterstaat initiated the Dutch Geo-Impuls program for reducing geotechnical failure. This joint industry programme aims to strengthen the geotechnical community by substantially reducing geotechnical failures in all types of construction projects. It started in 2009 and was completed in 2015. All of the more than 40 Geo-Impuls participants embraced Geotechnical Risk Management (GeoRM) as the preferred geotechnical working method. Parallel to, and in close cooperation with, the evolvements within the Geo-Impuls program, Rijkswaterstaat developed its own processes and practices, keeping Geotechnical Risk Management (GeoRM) and its associated GeoPrinciples in mind. Our paper for the ISGSR2013 addressed the implementation of GeoRM working methods in the organization. This paper aims to provide an overview of the unique set of GeoRM tooling that has been developed within RWS. These tools include an organization specific GeoRM guideline, which entirely fits the existing project management approach, the so-called Geo Project Sieve for quickly assessing and addressing the geotechnical risk profile of a new infrastructure projects. And furthermore an approach for risk-driven quality assurance and control after contract award, during design as well as construction of infrastructure projects. In addition to the descriptions of these tools, this paper gives specific attention to the results and benefits of the application of tool-supported GeoRM in a number of projects of RWS. It also addresses several activities that were carried out to implement GeoRM within the internal organisation. The results contribute for example to better cooperation between contract partners, in-time assessment and control of geotechnical risks, and therefore improved control of costs, time, and quality of services and civil works.