The bowing phenomenon is so relevant that two projects, EU funded, from 1999 studied it and a European Standard to assess the resistance to thermal and moisture cycles (influencing bowing) has been recently adopted. In particular, according EN 16306: 2013, measurements of bowing and flexural strength should be performed before and at the end of the ageing cycles. Additional non-destructive tests are recommended, but are not compulsory for the standard. Moreover, Annex A of EN 16306 contains guidance on the limit values for the selection of marble types suitable for outdoor uses, especially façade applications. Eleven varieties of marble have been tested by means of this laboratory ageing test. Non-destructive tests such as the measurements of ultrasonic pulse velocity (UPV), adjacent grains analysis, open porosity, and water absorption have been executed together with the conventional flexural strength test. The results obtained from image analysis on thin sections indicate that the AGA index may not always be correlated with the other tests: amount of bowing, loss of flexural strength, or loss of UPV. Some consideration of the decrease in mechanical resistance and the bowing in relation to the variety of marble tested and the limit values indicated in Annex A of EN 16306 can be noted. It is known that bowing and rapid strength loss occur in some varieties of marble when used as exterior cladding and other exterior applications. Additional conclusions have been drawn: bowing and flexural strength correlate well and can be used to assess the suitability of the marble to be employed in outdoors.

There is an increasing need for reliable methods to assess load-carrying capacity and remaining service life of existing infrastructure. Several previous research projects have resulted in a verified, simple 1D model for assessment of anchorage in corroded reinforced concrete structures. Previous verification has involved both experiments and detailed 3D NLFE analyses. To further develop the 1D model it needs to be extended to comprise more practical situations. In order to facilitate an efficient extension procedure in the future, the size of 3D NLFE model that is required to capture the bond behaviour between corroded reinforcement and concrete is investigated. Beam-end models and models of sub-sections were studied, and the results in terms of bond stress and crack pattern were compared. Preliminary results indicate good agreement for some situations; however for some cases a section model seems to overestimate the capacity.

Reinforced concrete is one of the most widely used building materials and if it is properly designed and produced, it is an extremely durable material with a service life up to 100 years. However, under certain environmental conditions the service life of reinforced concrete structures is more limited. Deterioration ofconcrete structure is in most cases caused by the penetration of aggressive media from the surrounding environment. Chloride initiated reinforcement corrosion is one of the major causes of deterioration of Concrete structures. One conflicting issue is how replacing Portland cement with mineral additions influences chlorideinitiated reinforcement corrosion. This issue is of immediate interest, as there is a steady growth in the use of cement blended with mineral additions, such as blast-furnace slag, fly ash and limestone filler. This is done by the cement and concrete industry to reduce the CO2 emissions linked to Portland cement manufacturing, bylimiting the use of clinker in the cement.The main objective of this work has been to further clarify the role of limestone filler as partial substitute to Portland cement on the two main decisive parameters for chloride induced reinforcement corrosion: chloride ingress rate and chloride threshold values. In the first part of this work the chloride ingress was studied both with accelerated laboratory methods and also after field exposure. The initial focus for the second part of the study was to determine the chloride threshold values for the binders investigated in the first part, so a comprehensive view of the effect of limestone addition on chloride initiated corrosion could be presented.However, during the work the need for the development of a practice-related method for determining the chloride threshold values was identified and the focus of the research was redirected to meet that need.The efficiency of limestone filler concerning chloride ingress showed to be dependent on replacement ratio, time (age) and on the test method. It was not possible to draw any rigid conclusion of the limestone filler’s efficiency regarding chloride ingress. But part of the inconsistency in the results was identified to be that limestone filler has two opposite effects on chloride ingress, on one hand contribute to a refinement of microstructure and on the other hand diminishing the chloride binding.The steel surface condition was shown to have a strong effect on the corrosion initiation, and can likely be one of the most decisive parameters attributing to the variability in the reported chloride threshold values obtained in laboratory experiments. The chloride threshold value for the sulphate resistant Portland cement fromthe laboratory experiments was estimated to be about 1% by weight of binder. For the concrete with limestone blended cement (CEM II/A-LL 42.5R) tested in this work the chloride threshold value was at the same level as for the sulphate resistant Portland cement. From the field study but with a somewhat different definition ofchloride threshold value, a chloride threshold value of about 1% by weight of binder was also estimated for ordinary Portland cement and sulphate resistance Portland with 5% silica fume exposed to marine environment.

This paper describes the synthesis and characterization of a set of textile reinforced reactive powder concrete (RPC) mixes that have been prepared in the framework of the SESBE project which aims to develop facade panels for the building envelope. In order to reduce the environmental impact, high concentration of type I and II mineral additions were added to the mixtures (up to 40% of cement replacement). The mechanical properties of the materials were analysed showing high values of compression strength thus indicating no disadvantages in the compression mechanical performance (∼140 MPa) and modulus of elasticity. In order to enable the use of these materials in building applications, textile reinforcement was introduced by incorporating layers of carbon fibre grids into the RPC matrix. The flexural performance of these samples was analysed showing high strength values and suitability for their further utilization.

One of the major issues with radiation from the natural isotopes 40K, 226Ra (238U) and 232Th and their decay products is the forthcoming legislation from the European Commission in relation to its Basic Safety Directive (2014). The European legislation is mandatory and could not be overthrown by national legislation. Hence, even though the BSS is still a directive it is foreseen as becoming a regulation in due time.

The reference value of the natural isotopes, from a radiation point of view, set for building materials is 1 mSv per year (EC, 2014). Earlier recommendations (The Radiation Protection Authorities in Denmark, Finland, Iceland, Norway and Sweden, 2000) within the Nordic countries set an upper limit at 2 mSv per year of radiation from building materials.

The main objective within the frame of the thesis was to investigate gamma radiation in relation to Swedish aggregates and their use as final construction products and the applicability and use of a model (EC, 1999) for building materials to calculate the effective dose within a pre-defined room. Part of the thesis also investigates different methodologies that can be used to assess the radiation in a construction material made up of several constituents (building materials) and aims to show that for some purposes as for the construction industries (precast concrete), that a hand-held spectrometer can be used with good accuracy, even though the object is limited in thickness and size. Secondly, the author proposes a simplified way of assessing the radiation in a construction material by use of correlation coefficient of a specified recipe by use of a hand-held spectrometer. Moreover, an understanding of the different building materials´ contribution to the finalized construction product, e.g. concrete is demonstrated, and how to achieve a good control of the radiation levels in the concrete building.

The reference level for effective dose due to gamma radiation from building materials and construction products used for dwellings is set to 1 mSv per year (EC, 1996, 1999), (CE, 2014). Given the specific conditions presented by the EC in report 112 (1999) considering building and construction materials, an I-index of 1 may generate an effective dose of 1 mSv per year. This paper presents a comparison of the activity concentrations of 4 0K, 226Ra and 232Th of aggregates and when these aggregates constitute a part of concrete. The activity concentration assessment tool for building and construction materials, the I-index, introduced by the EC in 1996, is used in the comparison. A comparison of the I-indices values are also made with a recently presented dose model by Hoffman (2014), where density variations of the construction material and thickness of the construction walls within the building are considered. There was a ~16-19% lower activity index in concretes than in the corresponding aggregates. The model by Hoffman further implies that the differences between the I-indices of aggregates and the concretes' final effective doses are even larger. The difference is due, mainly to a dilution effect of the added cement with low levels of natural radioisotopes, but also to a different and slightly higher subtracted background value (terrestrial value) used in the modeled calculation of the revised I-index by Hoffman (2014). Only very minimal contributions to the annual dose could be related to the water and additives used, due to their very low content of radionuclides reported.

Abstract Water-repellent mortars were prepared using different hydrophobic compounds as admixtures. Calcium and zinc stearates, silane/siloxane products (as liquid solution and powder) were mixed into limestone cement mortars for obtaining in-bulk water-repellent mortars suitable for building protection and resistant to the degrading action of water. The influences of the admixtures on the hydration and structure of the designed mortars were investigated by SEM, TG–DSC, FT-IR, XRD, and isothermal calorimetry. The effectiveness of these agents against water action was evaluated by using techniques and methods such as mercury intrusion porosimetry, water absorption tests and contact angle measurements. Siloxane products conveyed good water-repellent effectiveness, without strongly influencing the setting and hydration of the binder, while the zinc stearates slowed down the hydration reactions.

The SESBE research project aims to develop novel smart sandwich façade elements with high insulating capabilities while providing a reduced thickness in conjunction with superior mechanical and durability properties. The present paper mainly focuses on the verification of the mechanical performance of the glass fibre reinforced polymer (GFRP) connectors in the façade element composed of reactive powder concrete (RPC) panels with foam concrete insulation between them. Because of the reduced thickness of the large façade elements, the performance of the connectors is critical for the entire structural concept. A description of structural performance and results based on experimental methods and finite element (FE) analysis are presented.

Ordet renovering existerar inte i något av våra regelverk. Begreppet renovering ingår i det som benämns ändring av en byggnad i vilket ombyggnad ingår som en del.De tekniska egenskapskrav som gäller vid nybyggnad gäller i princip också vid ändring. Vid ombyggnad ska de uppfyllas för hela byggnaden eller, om detta inte är rimligt, den del av byggnaden som påtagligt förnyas genom ombyggnaden. Vid ändring gäller de för ändringen. Enkelt avhjälpta hinder mot tillgänglighet till eller användbarhet av lokaler dit allmänheten har tillträde ska dock alltid avhjälpas.När det gäller ändringar tillkommer dock ett krav på varsamhet, d.v.s. att man tar hänsyn till byggnadens karaktärsdrag och tar till vara byggnadens tekniska, historiska, kulturhistoriska, miljömässiga och konstnärliga värden. En byggnad som är särskilt värdefull från historisk, kulturhistorisk, miljömässig eller konstnärlig synpunkt får inte förvanskas.Kravet på varsamhet och förbudet mot förvanskning innebär att det är nödvändigt att ibland göra avsteg från de rent tekniska egenskapskraven som gäller vid nybyggnad när man genomför en ändring.Ändringsreglerna i BBR och EKS avser att förtydliga vilka av de egenskapskrav som gäller vid nybyggnad som man inte får göra avsteg från och i vilka fall det är möjligt att mot bakgrund av ändringens omfattning och byggnadens förutsättningar göra anpassningar.Vad som avses med ändringens omfattning och byggnadens förutsättningar förtydligas i BBR. När det gäller ändringens omfattning utgås från hur stor del av byggnaden som berörs, konsekvenserna för de tekniska egenskapskraven och byggnadens kulturvär-den. Motiveringar med hänsyn till byggnadens förutsättningar kan dels ha att göra med om det är fråga om omfattande ändringar eller ny användning. I sådana fall finns få skäl till avsteg från nybyggnadsnivån. Är det fråga om en kulturhistoriskt värdefull byggnad finns det större skäl. Tekniska skäl, som t.ex. att utrymme saknas eller att uppfylla ett krav medför att ett annat inte blir uppfyllt på ett godtagbart sätt kan också åberopas. Ekonomiska skäl baserade på byggnadens placering, utformning eller tekniska förutsättningar kan också vara motiveringar. Låg likviditet får dock inte beaktas. Därutöver kan även boendekvaliteter av praktisk eller upplevelsemässig art utgöra skäl för anpassning.Kravnivån vid ändring varierar också beroende på vilket krav det är fråga om. I BBR och EKS används följande terminologi:Ska: I princip inget utrymme för avvikelseSka ...om inte synnerliga skäl: Visst modifieringsutrymme finns om byggnaden ändå kan antas få godtagbara egenskaper och det inte är möjligt att tillgodose kravet fullt ut utan höga kostnader eller påtagligt negativa konsekvenser för övriga tekniska egen-skapskrav eller byggnadens kulturvärden.Ska eftersträvas: Kraven ska tillgodoses om det kan ske till en skälig kostnad och inte medför negativa konsekvenser för övriga tekniska egenskapskrav, byggnadens kulturvärden eller andra boende- och brukarkvaliteter. Har byggnaden redan den eftersträvade egenskapen finns inte utrymme för att försämra den om det inte finns synnerliga skäl.Dock får anpassningar av kraven aldrig medföra en oacceptabel risk för människors hälsa och säkerhetEn hel del av det som står i BBR, EKS och Hissreglerna är allmänna råd och inte absoluta krav, och ger exempel på godtagna konstruktionslösningar. Dessa är inte alltid möjliga att tillämpa vid ändring, utan man måste söka andra lösningar som ändå ger samma säkerhet.Reglerna ger för de olika egenskapskraven vägledning för eventuella anpassningar, förslag på alternativa lösningar t.ex. moderniseringar då äldre byggteknik använts.I hyreslagstiftningen är det främst två aspekter som berör ändringar: Hyresgästinfly-tande vid förbättrings- och ändringsarbete och villkor vid större förändring av hyran. I båda dessa fall krävs godkännande av hyresgäster eller tillstånd av hyresnämnd. Dock står det inget om att hyresgäster kan var med och påverka vad som ska ändras, t.ex. hur omfattande ändringarna ska vara.När det gäller bostadsrätter är det hur stora beslut ska tas som avhandlas. Om alla medlemmar inte är eniga har hyresnämnden en roll även här. En bostadsrättsinneha-vare har rätt att frånträda en bostadsrätt om avgiftsändringarna blir för stora. Bostadssätten återgår då till föreningen, mot skälig ersättning.

The purpose of this paper is to numerically simulate the in-plane behaviour of rammed earth walls under cyclic shear-compression tests. The experimental testing allowed obtaining the maximum horizontal loads, the displacement capacity and the level of non-linear behaviour of the respective load-displacement relationships as well as the failure modes. The calibration of the numerical model (finite element method) was carried out based on the experimental results. Within this framework, a micro-modelling approach was considered. The behaviour of the rammed earth material was simulated using a total strain rotating crack model. A Mohr-Coulomb failure criterion was used to reproduce the behaviour of the interfaces between the layers. Although the numerical results achieved a satisfactory agreement with the experimental results a sensitivity analysis of the parameters involved was performed. The sensitivity analysis aimed at determining which parameters of the model have a significant impact in the model's results. As expected the sensitivity analysis pointed out that the sliding failure occurrence is mainly influenced by two parameters of the interface elements: the interface tensile strength fit and the friction angle φ. Moreover the cohesion c and the layers thickness showed a limited effect on the shear behaviour. It should be noted that the results mentioned above are related to the cases where a significant level of vertical compressive stress σ is employed.

In this paper a modelling approach is presented to reproduce the mechanical behaviour of sandwich panels via finite element analysis. Two types of panels were investigated in this scope of work. The first sandwich element was a textile reinforced concrete (TRC) panel with cellular lightweight concrete insulation and the second configuration was an ultra-high performances concrete (UHPC) panel with aerated autoclaved concrete insulation. The goal was to obtain a reliable numerical strategy that represents a reasonable compromise in terms of sufficient accuracy of the element characteristics and the computational costs. The results show the possibility of describing the composite action in a full sandwich panel. The achieved modelling approach will later be used for the optimization of TRC and UHPC panels in terms of minimizing the thickness, identifying the number and location of connectors, as well as evaluating varying anchorage systems.

The awareness of the environmental impact of the building sector is increasing. Steel reinforced concrete is the most commonly used construction material, though with a high-embodied energy and carbon footprint. Large environmental gains may arise if an alternative to steel reinforced concrete is developed. In this context, ultra-high performance concrete (UHPC) materials are shown to be promising alternatives with advantages such as lower embodied energy and reduced environmental impact. Predictions suggest that UHPC composite elements for building envelopes could have other benefits such as an increased service life, optimised use of building area due to thinner elements and minimised maintenance due to the absence of reinforcement or use of non-corrosive reinforcing materials such as carbon fibres. In the framework of the H-HOUSE project funded by the European Commission, composite elements are developed. The aim is to create facade panels combining an autoclaved aerated concrete or cellular lightweight concrete insulation layer with an external UHPC supporting layer. To enhance occupant comfort and health, hygroscopic materials that are capable to buffer indoor air humidity shall be applied to the inside of such elements. Indoor air humidity levels are expected to be more stable, which shall subsequently improve the indoor climate and minimise potential decay to the construction.

The current paper focuses on the determination of reliable numerical models of earth block masonry wallettes under different loading conditions. Uniaxial compression and diagonal compression tests were performed. Experimental behaviour was modelled with a non-linear model able to describe the cracking behaviour. The simplified approach based on macro-modelling shows a satisfactory accuracy and low computational costs. The results reproducing the uniaxial compression are in good correspondence with the post-elastic behaviour observed in the experimental campaign. The micro-modelling approach adopted to reproduce the shear behaviour, even with high computational cost, represents a suitable tool to predict the masonry collapse mechanism.

The study presents the results from the development of a grouting material based on hydrated lime with addition of pozzolana, which is referred to as hydraulic lime, suitable for the repair of cracks in a variety of earthen building techniques. The goal was to develop a material also compatible with earthen structures exposed to dynamic loads. The grouting mortar was designed to be adaptable in strength properties and at the same time to have sufficient robustness for preparation and use on the construction site. Results showed a satisfactory performance of the grout concerning fresh and hardened mortar properties as well as injectability.

Sustainability is not only a matter of choosing durable stone types for a specific application. It is also about theenergy consumed during the production, transportation and placing of the stone. It is also about dimensioningand shaping of the stone properly for the actual construction and the stone together with other materials in theconstruction. This contribution deals with the latter and is a case study on a failed paving construction.Stone paving is the collective expression for the use of stone slabs, setts and kerbs for exterior paving purposes.There are three European product standards in force; EN 1341, 1342 and 1343 respectively. These standardsdescribe e.g. how to denominate the products, the allowed dimensional tolerances and which technical propertiesto validate. There is little or no information on the actual usage of these products. Such information has generallyto be elaborated by each country.The standard way of construction for pavements is non-bonded laying of elements in crushed sand/splitmixtures. Under special loads and cleaning requirements this traditional, unbound construction method easily failsand a bound construction is needed. The structural integrity of an unbound pavement construction is maintainedon the basis of friction and mechanical interlock. Energy from traffic loading enters the structure via the surfacecourse, some of this energy is dissipated within the surface course itself and some is transmitted into the beddingcourse and thereafter the supporting base layers beneath. There are two structural elements in the surface course,the setts and the jointing medium. The jointing medium has physical properties which are important to consider,such as stiffness modulus, resistance to shear et al, which crucially affect the manner in which the pavementresponds to applied loads.Sufficient friction between the various components is crucial but is not generated and mechanical interlock notexercised without movement of the component parts of the structural model. The unbound paving is not a rigidconstruction and the various parts of this structural model must be mobilised in order that friction is generated.The paving is therefore also heavily dependant upon the unseen surface finishing of the setts (and slabs). In orderto adequately generate friction between the paving element and both bedding and jointing materials the unseensurfaces have to be rough, preferably a cleft or riven surface, to function properly.There are two distinct categories of setts, shallow setts and full setts, each requiring a different approach:Shallow setts are those having depth less than width.Specifying shallow setts makes a more economical use of the raw material used in their manufacture but thepavement construction requires to designed more carefully and there is an upper limit to the level of traffic whichcan be carried. A concrete base must be provided when specifying shallow setts.Full setts are those having depth not less than width.For many centuries the "golden rule" was that setts must be at least as deep as they are wide. The heavier thetraffic loading, the deeper the sett in relation to its width. Before the advent of concrete and mortar, when jointing,bedding and supporting base were all unbound, this rule was very necessary. Even with the development of highperformance mortars and reinforced concrete for a base, we need to use full setts when the traffic loading exceedsa given maximum.The deeper the sett in relation to its width, the more the strength of the pavement is taken by the joints between thesetts. So, with deep, full setts we can sometimes lay over an unbound or a bituminous base, even for heavy traffic.As can be seen, these simple rules given above depend on proper definition of the traffic loads. i.e. numberof vehicles per day and the weight of them. When the general rules are not followed the stones start to move inan uncontrolled manner. Some cases and one in particular will be detailed in this presentation. The case studiesdemonstrate the importance of the necessary knowledge needed to build a paving that can cope with the dynamicand static traffic loads. In addition, it shows the problem that may arise due to a poorly defined border betweensetts and slabs.

Analyses of tested two-way reinforced concrete (RC) slabs were carried out with varying modelling choices to develop better modelling strategies. The aim was to study how accurately the response of a slab subjected to bending could be predicted with nonlinear finite element (FE) analysis using three-dimensional (3D) continuum elements, and how the modelling choices might influence the analysis results. The load-carrying capacity, load-deflection response, crack pattern and reaction-force distribution of the two-way slab studied were compared to experimental data available. The influence of several modelling parameters was investigated, including geometric nonlinearity, element properties, concrete model, reinforcement model and boundary condition. The results show the possibility of accurately reflecting the experimental results concerning load-carrying capacity, load-deflection response and crack pattern giving proper modelling choices. Moreover, the reaction force distribution was found to be highly influenced by the stiffness of the supports.

Failure of reinforced concrete (RC) slabs in punching has been a challenging problem for nonlinear finite element (FE) analysis. To improve the analysis approach, this study was conducted by developing a nonlinear FE analysis method for slabs subjected to punching failure, using three-dimensional continuum elements. The influence of several modelling choices were investigated by comparing such results as load carrying capacity, load-deflection response and crack pattern from the FE analyses with available experimental data. The proposed method show the possibility of accurately predicting the load-carrying capacity and realistically describing the behaviour of slabs.

This study was conducted by carrying out nonlinear FE analysis of RC slabs subjected to punching failure, using three-dimensional (3D) continuum elements. The influence of several modelling choices for concrete material were investigated by comparing results such as load-carrying capacity, load-deflection response and crack pattern from the FE analyses with available experimental data. The analyses of the tested slabs show possibility to accurately predict the load-carrying capacity and realistically simulate the behavior of slabs using the proposed method.

Failure of reinforced concrete (RC) slabs without shear reinforcement in punching has been a challenging problem for nonlinear finite element (FE) analysis. To improve the analysis approach, this study was conducted by developing a nonlinear FE analysis method for slabs subjected to punching failure without shear reinforcement, using three-dimensional continuum elements. The influence of several modelling choices were investigated by comparing such results as loadcarrying capacity, load-deflection response and crack pattern from the FE analyses with available experimental data. The proposed method shows the possibility of accurately predicting the load-carrying capacity and realistically describing the behaviour of slabs.

This paper describes the development of a common Nordic test method for the evaluation ofhydrophobic impregnations for concrete, for protection against chloride ingress. The first stage of theexperimental campaign served to evaluate the influence of the precondition environment before surfacetreatment, curing time and type of surface on the performance of the impregnation agent. In the secondstage, a round robin test involving 3 Nordic laboratories was conducted; the results showed very littlevariation and were compared to results obtained according to previous standards in order to defineperformance requirements. Finally, data from field exposed specimens for more than 5 years was used tovalidate the suitability for use.

This paper describes the initial steps towards the development of a foam concrete-aerogelcomposite for thermal insulation in lightweight sandwich façade elements. Fire safety is an important issuepertaining insulation materials. Therefore, the need for low-density inorganic, non-flammable materials israpidly increasing. Foam concrete is a lightweight material with good thermal characteristics; densities aslow as 400 kg/m3 and thermal conductivities as low as 100 mW/m·K can easily be achieved. The mainadvantage when compared to typical inorganic insulations (e.g. autoclaved aerated concrete or mineralwool) is that foam concrete has a much lower embodied energy, in particular due to the simplicity of themanufacturing process. However, in order to be competitive as an effective insulation material, thethermal conductivity needs to be drastically reduced which can be achieved by reducing the density andby incorporating silica aerogels (both measures affecting the compressive strength).

In assessing existing structures, inspection results need to be linked to the effects on load-carrying capacity; to provide such information, this study has investigated the correlation between splitting crack width, corrosion level and anchorage capacity. The study was based on 13 reinforced concrete beams that had been exposed to natural corrosion for 32 years, 11 beams with splitting cracks and 2 without. The crack pattern and widths were documented before undergoing structural testing of anchorage capacity. Thereafter, the reinforcement bars were extracted and their corrosion levels measured using two methods, gravimetric weight loss and 3D scanning. The corrosion level from the weight loss method was approximately twice as large; possible reasons are horizontal or subsurface corrosion pits, and the cleaning method. Further, for the same corrosion level, the specimens in this study had much larger crack widths and slightly lower bond capacity than the artificially corroded tests in the literature; a possible reason is that these specimens had been subjected to combined corrosion and freezing. However, the corrosion level and reduction in bond capacity related to crack width were both lower in the present than in previous studies in the literature. Thus, by formulating a damage indicator from the damage visible in the form of crack widths from artificial test data, the structural capacity is estimated to be on the safe side.

This paper presents some durability and service life models for reinforced concrete structures with regard to chloride ingress, carbonation and frost attack. In the past years a number of models for durability design of concrete structures have been suggested by relevant organisations or international committees. It is necessary to validate these models against long-term field data for their applicability with respect to exposure climate in order to satisfactorily use the models in the durability design and redesign of concrete structures. In this study, various potential models for concrete resistance to chloride ingress, carbonation and frost attack were briefly reviewed. Three models including the simple ERFC, the DuraCrete and the ClinConc, for prediction of chloride ingress were evaluated using the infield data collected from both the field exposure site after over 20 years exposure and the real road bridges of about 30 years old. A physicochemical model for prediction of carbonation depth was evaluated using the infield data collected from the field exposure site after 11 years exposure and the limited data from the real structures with the age of 7-13 years. For the modelling of frost attack, some problems in measurement of critical saturation degree and actual degree of saturation are discussed. According to the comparison results, the simple ERFC overestimates whilst the DuraCrete model underestimate the chloride ingress in most cases. The ClinConc model on the other hand gives reasonable good prediction for both the short-term (one year) and the long-term (21 years) exposure. The Papadakis model for carbonation also gives fairly good prediction of carbonation depth when compared with the Norwegian infield data classified as exposure class XC3|, but underestimates the carbonation depths when compared with the infield data from Norwegian structures in exposure class XC4.

ACCIONA Infrastructure, a Spanish contractor, uses the caisson method for the construction of breakwater structures. One of its floating docks, Kugira, is one of the largest of its kind in the world and it can produce concrete caissons measuring 70 m long by 36 m wide and 35 m high. Concrete caissons made in floating docks are gradually immersed in sea water as they are built; thus, the set concrete is exposed to sea water at a very early stage, within 18 to 48 hours after casting in sliding formwork. In order to study the durability of slag concrete using this construction method, the properties of concrete exposed to sea water at a very young age have been tested. Specimens were exposed to artificial sea water by the ponding method at different ages (16h, 1, 2, 3, 7 and 28 days) for a period of 6, 18 and 36 (analysis pending) months. The following properties were measured and compared with unexposed specimens: compressive strength, water and oxygen permeability, pore size distribution, migration coefficient DNT492 and chloride profiles. After 6 and 18 months ponding, lower chloride contents were measured for the specimens exposed to sea water after 28 days curing compared to those exposed at early ages. However, this difference significantly decreases within a small depth from the exposed surface. Also the migration coefficient DNT492 decreases significantly with the increase of the age of the concrete. With regards to water and oxygen permeability, no significant differences were found. In this paper, a summary of all these works is presented.                

ACCIONA Infrastructure, a Spanish contractor, uses the caisson method for the construction ofbreakwater structures. One of its floating docks, Kugira, is one of the largest of its kind in the world and itcan produce concrete caissons measuring 70 m long by 36 m wide and 35 m high. Concrete caissonsmade in floating docks are gradually immersed in sea water as they are built; thus, the set concrete isexposed to sea water at a very early stage, within 18 to 48 hours after casting in sliding formwork. In orderto study the durability of slag concrete using this construction method, the properties of concrete exposedto sea water at a very young age have been tested. Specimens were exposed to artificial sea water by theponding method at different ages (16h, 1, 2, 3, 7 and 28 days) for a period of 6, 18 and 36 (analysispending) months. The following properties were measured and compared with unexposed specimens:compressive strength, water and oxygen permeability, pore size distribution, migration coefficient DNT492and chloride profiles. After 6 and 18 months ponding, lower chloride contents were measured for thespecimens exposed to sea water after 28 days curing compared to those exposed at early ages.However, this difference significantly decreases within a small depth from the exposed surface. Also themigration coefficient DNT492 decreases significantly with the increase of the age of the concrete. Withregards to water and oxygen permeability, no significant differences were found. In this paper, a summaryof all these works is presented.Apart from this laboratory analysis, real scale tests were performed at site with the aim to increasedurability by the addition of nanosilica particles. The characterization of these real scale tests are alsodescribed and discussed in this paper.

Textile reinforced concrete (TRC) has emerged as a promising alternative wherein corrosion is no longer an issue and much thinner and light-weight elements can be designed. Although TRC has been expansively researched, the formalization of experimental methods concerning durability arises when attempting to implement and design such innovative building materials. In this study, accelerated ageing tests paired with tensile tests were performed. The change in physico-mechanical properties of various commercially available textile reinforcements was documented and evaluated. The ability for the reinforcements to retain their tensile capacity was also quantified in the form of empirical degradation curves. It was observed that accelerated test parameters typically applied to fibre-reinforced polymer (FRP) bars and grids are generally too aggressive for the textile reinforcement products and alternative boundary conditions are necessary. The developed degradation curves were found to have an overall good correlation with the experimental findings.

Conventional steel reinforced concrete is one of the most commonly used building materials,yet it has shortcomings in terms of weight, thick concrete covers, and durability namely corrosion of thereinforcement. Textile Reinforced Concrete (TRC), a combination of fine-grained concrete and noncorrosivefibre grids, has emerged as a promising alternative; corrosion is no longer an issue and muchthinner and light-weight elements can be designed. Although TRC has been expansively researched,unknowns pertaining to the long-term durability arise when attempting to implement such innovativebuilding materials. The aim of this article is to study the effect of accelerated aging on the tensile strengthof various textile fibre grids according to ISO 10406-1 [1]. Carbon, basalt and alkali-resistant (AR) glassfibre grids were immersed into high alkali environment and elevated temperature for 30 days. Directtensile tests were conducted before and after aging to observe the degree of stiffness and tensile strengthloss. After aging, the carbon fibre grids were marked by an increase in both tensile strength and stiffness,while AR-glass and basalt were degraded to the extent that tensile tests could not be conducted.Specimens were therefore exposed to alternative conditions to identify the governing degradation factor.

In this paper, both experimental and numerical methods are presented to gain an understanding of the structural behaviour related to a TRC sandwich panel with a glass fibre reinforced polymer (GFRP) plate connection system. Double shear tests were conducted on component-scale sandwich panels to characterize the available shear capacity provided by the connectors and panel configuration. Three-dimension (3D) non-linear Finite Element Analysis (NLFEA) was applied to develop a model for the design of TRC sandwich panels while focusing on the connectors. The experimental outcome of the shear tests was applied to validate the corresponding numerical model developed in this work. The need for further modifications to the design of the shear connectors or other parameters such as panel thickness can be established accordingly. This developed FE model can essentially be applied as a design tool to further predict the structural behaviour of the full-scale sandwich elements.