Academic literature on the topic 'Historical masonry'

Strengthening historical brick masonry walls is important because these walls are major load-bearing members in many architectural heritages. However, historical brick masonry has low elastic modulus and low strength, historical masonry walls are prone to surface treatment or other structural intervention, and some of the walls lack integrity. These characteristics make effective strengthening of historical masonry walls difficult. To address the issue, strengthening layers made up of ultra-high performance concrete (UHPC) are potentially useful. To investigate the strengthening effect of the UHPC layers, the authors constructed three squat walls using historical bricks and mortar collected from the rehabilitation site of a historical building, and strengthened two of the walls with a UHPC layer and a reinforced polymer mortar layer respectively. The three walls were broken down by horizontal cyclic force along with constant vertical compression, and then the unstrengthened one was strengthened in-situ by a UHPC layer and was tested again. The experimental results indicate that the UHPC layers significantly improved the in-plane shear resistance and cracking load of the squat walls, without decreasing the walls’ ultimate deformation. They effectively strengthened both moderately and severely damaged historical masonry walls, because the UHPC filled the existing damages and improved the integrity of the masonry substrate. In addition, the UHPC layers intervened the historical walls less than the reinforced polymer mortar layer. Therefore, the UHPC layers are efficient in strengthening historical squat masonry walls.

The paper discusses selected aspects on numerical modelling of historical masonry structures. Linear elastic material models are mentioned first, and then non-linear models are discussed. The paper includes several examples of solutions which have been done with use of these models. There is also an example of results which can be obtained from anon-linear analysis of masonry structures. The finite element method is used for computations.

The article provides an overview of historic masonry towers such as the minarets of mosques, bell towers of churches, clock towers, leaning towers, so-called "falling towers" and ruined towers. It was considered what kind of masonry, what kind of mortars the Romans, the ancient Egyptians, the Inca and Mayan cultures in America used. Some aspects of seismic vulnerability of masonry towers were studied. The modes of destruction of thin masonry structures, mechanisms of destruction of masonry in towers are considered, the seismic behavior of historical masonry towers are considered, and one of the methods of seismic strengthening using an innovative "smart" material is presented.

The article provides the analysis of the causes of damage in the masonry of historical buildings after their restoration. It has been established that the use of mortars of an increased grade and, accordingly, stiffness during repairs of historical masonry leads to an increase in tensile stresses in bricks under temperature and humidity effects. The reasoning behind the use of such mortars is to increase the strength and durability of the restored areas of historical masonry. The results of numerical simulation show that the masonry mortar must be sufficiently strong in compression and, at the same time, sufficiently plastic. It is shown that the use of hard mortars based on a cement binder, compared with plastic mortars based on a lime binder, on average doubles the value of normal tensile stresses at a temperature difference ∆Т=+100С.. This effect is much higher when stones swell due to their moisture. According to the results, for restoration work with brickwork, one should use mortars in accordance with the technology corresponding to this historical period, i.e., lime with additives that were identified during laboratory tests of samples taken from historical masonry. Low-grade mineral solutions with a low modulus of elasticity are preferable. It increases the crack resistance of the masonry under temperature and humidity effects. The article also shows that improper jointing of masonry joints facilitates the destruction of masonry. It happens when areas of accumulation of rainwater are formed, leading to increased wetting of stones in areas of direct impact of rainfall.

In order to study the dynamic response of historical masonry structures, a scaled down brick masonry model constructed in civil engineering department at Baghdad University to simulate a part of a real case study, which is Alkifil historic minaret. Most of the previous researches about masonry structures try to understand the behavior of the masonry under seismic loading by experimental and numerical methods. In this paper, the masonry units (bricks) simulated in scale (S= 1/6) with the exact shape of the prototype bricks. Cementitious tile adhesive was selected to be the mortar for the modeling. The height of the model designed to be 1.5 m with a 0.5 m diameter. Detailed construction steps were presented in this paper. Experts built the model with high accuracy. A shaking table and other dynamic testing facilities were used at the University of Baghdad. The model was tested using the time-compressed El Centro 1940 NS earthquake at different amplitudes. The first ground motion of (PGA= 0.05g) which considered as weak ground motion was used to check the adequacy of the conventional behavior of the masonry model and the limit of the elastic behavior of the model during weak earthquakes. Moderate ground motion (PGA=0.15g) was performed to investigate the response of the model with minor to moderate damages. The severe ground motions were not appropriate to use in such circumstances because of the possibility to overturn the model. The experimental results showed very adequacy of the model to withstand the weak and moderate earth motion with no observed cracks.

The moisture content in historical masonry walls, particularly on the ground floor, caused by i.e. lack of damp insulation, is a phenomenon of common occurrence. It is usually analysed in terms of mycological changes, thermal insulation and frost damage. The paper discusses the influence of the increased moisture content on the weight and load bearing capacity of the structure. The determination of moisture content in masonry elements, performed during the inspection of the building, provides information from which an increase in the structure's weight can be defined. Reliable tests for the moisture content and compressive strength of masonry and mortar components are invasive, and the number of testing in historical buildings should be limited to the minimum necessary to preserve their vintage nature. As a result, the received overall picture of the work of masonry may not be consistent with its actual state since historical buildings could have been rebuilt or repaired, and consequently, contain masonry conversions made of various materials with different properties. Absorbability can serve here as an example as it is a factor that disrupts a reliable determination of load bearing capacity values of masonry structures. The article attempts to determine the change in load bearing capacity of a moist masonry structure compared to the original - in the air-dry state - for various types of historical masonry and mortar components. The main influence analysed was due to capillary action, whereas the effect of other sources of moisture, i.e. salinity, was excluded.

The reliability of historical buildings` brick structures is usually evaluated on the basis of analysis based on empirical formulas that use characteristics of brick and masonry mortar, which are obtained as a result of testing samples of materials taken from the structures. The practice of making such evaluations often shows an obvious discrepancy between the visual state of the structure and the analysis results obtained. Brick-masonry that does not have signs of the load-bearing capacity loss may be evaluated as emergency brick-masonry, and structures that have clearly lost their integrity are sometimes assumed to be sufficiently reliable. The currently valid regulatory documents provide for the possibility of using standard samples for direct evaluation of the strength of brickwork, but it requires adaptation to the conditions of the of historical objects` survey. This paper presents substantiation for the need of using standard samples to evaluate the strength parameters of historical objects` masonry.

Masonry bricks were widely used in construction of the walls in most of Chinese historical buildings. The low strength of lime–clay mortar used in existing historical brick masonry walls has usually led to poor performance such as cracking and collapse during earthquakes. As the composition of modified oyster shell ash mortar (MOSA mortar) with higher strength is similar to that of lime–clay mortar, it can be used to partially replace original lime–clay mortar for historical brick masonry buildings in order to improve their seismic performance. Previous research has proven that this strengthening method for brick masonry is effective in improving shear strength. In this paper, we present further experimental research regarding the compressive behaviors of brick masonry strengthened by replacing mortar with a MOSA mortar. The test results showed that the compressive strength of brick masonry specimens strengthened by the proposed method meets the design requirements. The formula for calculating compressive strength for brick masonry strengthened by replacing mortar was obtained by fitting the test results. The calculated values were consistent with the tested ones. In addition, the stress–strain relationship of tested specimens under axial compression was simulated using the parabolic model.

The conservation of historic structures has been given special attention due to their cultural, social and economic importance. However they often show considerable structural vulnerability and have been seriously damaged by natural disasters including earthquakes. An excessive loss of architectural heritage has occurred because of earthquakes. A safety assessment and restoration practice on historical structures has been tackled extensively by professionals including architects and engineers. However, structural assessment of historical buildings is a complex task. Complexity comes from insufficient understanding of the characteristic of historical materials, limited knowledge of the seismic response of historical structures and yet-unknown structural deterioration due to the past natural disasters. Today it is perceived that nonlinear FEM analysis permits detailed study of historical masonry structures. However, in some cases, its application poses difficulties. The difficulties derive from the definition of material properties, the definition of a complex geometry and the analysis procedures. The results depend on the material properties considerably. However, it is not easy to describe appropriately the behaviour of historical materials including masonry in the FEM analysis. The definition of a complex geometry is challenging although the discretisation of accurate geometry is crucial. As for the analysis procedure, one of the difficulties is observed in seismic assessment. FEM-based nonlinear dynamic analysis permits close observation of seismic response of a historical masonry structure but it requires excessive computational effort, for a large-scale structure in particular. On the other hand, pushover can be adopted more efficiently than nonlinear dynamic analysis but the obtained result can be less reliable. All these considerations indicate that the understanding of FEM approaches still needs to be deepened to adopt more accurately and at the same time efficiently for the analysis of historical structures. The present research discusses the applicability of existing nonlinear FEM approaches to the study of masonry historical structures. The FEM analysis is adopted to the analysis of real and complex structures including mixed steel and masonry vaulted systems belonging to the Hospital de Sant Pau in Barcelona and a large single-nave church damaged by the 2009 Abruzzo earthquake. As a final outcome of the research, the conclusions provided criteria and guidelines for the analysis of these types of structures under vertical loading and seismic forces. The achievement of the research will contribute to both engineers and researchers who are involved in the conservation of historical masonry structures especially by means of FEM analysis.
La conservación de las estructuras históricas llama la atención debido a su importancia cultural, social y económica. Sin embargo, muestran considerablemente vulnerabilidad estructural y se han dañado seriamente por desastres naturales como terremotos. La excesiva pérdida de patrimonio arquitectónico ha ocurrido a causa de los terremotos. Se ha llevado a cabo la evaluación de la seguridad y la práctica de restauración de estructuras históricas ampliamente por los profesionales incluso arquitectos e ingenieros. No obstante, la evaluación estructural de los edificios históricos es una tarea compleja. La complejidad viene de la comprensión insuficiente de las características de los materiales históricos, conocimiento limitado de la respuesta sísmica de estructuras históricas y deterioro estructural todavía desconocido debido a los desastres naturales pasados. Hoy en día se percibe que el análisis de elementos finitos (FEA) no lineal permite el estudio detallado de las estructuras de mampostería históricos. Con todo, en algunos casos, no es sencilla la aplicación de ello. Las dificultades vienen de la definición de las propiedades del material, la definición de una geometría compleja y los procedimientos de análisis. Los resultados dependen de las propiedades del material considerablemente. Sin embargo, no es fácil describir adecuadamente en el FEA el comportamiento de materiales históricos como mampostería. Es difícil definir la geometría compleja es crucial aunque la discretización de la geometría exacta. En cuanto al procedimiento de análisis, se observa una de las dificultades en la evaluación sísmica. Análisis dinámico no lineal del FEA permite la observación precisa de la respuesta sísmica de las estructuras de mampostería histórica pero requiere el esfuerzo computacional excesivo, especialmente por una estructura a gran escala. Por otro lado, pushover puede ser más eficiente que el análisis dinámico no lineal pero el resultado obtenido por ello puede ser menos fiable. Estas consideraciones indican que la compresión del FEA necesita profundizarse para que se adopte FEA más precisamente y más eficientemente para el análisis de estructuras históricas. La presente investigación analiza la aplicabilidad del FEA no lineal acerca del estudio de las estructuras históricas de mampostería. El FEA se adopta para el análisis de las estructuras reales y complejas incluso los sistemas abovedados de la combinación del acero y mampostería pertenecientes al Hospital de Sant Pau de Barcelona y una gran iglesia de una sola nave dañada por el terremoto de Abruzzo 2009. Como resultado final de la investigación, las conclusiones presentan criterios y directrices para el análisis de estés tipos de estructuras bajo cargas verticales y sísmicas. El fruto de la investigación contribuirá a ambos ingenieros e investigadores que participan en la conservación de las estructuras de mampostería históricos sobre todo por medio del FEA.

Historical masonry structures are important cultural assets which reveal the social, archaeological, aesthetic, economical, political, architectural and technical features of their times. Within the course of the time, the structures have been exposed to the destructive effects of the nature and the man. Some has been able to survive somehow and others were totally ruined. Most of the remained structures are in vulnerable condition to upcoming effects and for the continuity of their presence, structural strengthening applications are needed. A variety of applications are used with different levels of respect to original fabric and different extents of intervention within the principles of international charters that regulate the intervention on historical monuments. In this study, a method of strengthening for the historical masonry constructions is developed in a general sense by the use of steel skeleton systems. In the proposed methodology, it is aimed to approach the intact structural conditions as much as possible in the strengthened structure. For the study a 3D model is created to compare the behaviors of the intact and the modified structure. In the modified model some structural elements are replaced by the steel skeleton system as a strengthening application. The behavioral investigation of the two models is performed in the finite element platform. Finally, it is certified that this methodology successfully efficient in approaching the original intact condition of the structure under concern as well as complying with the restoration principles.

Masonry has been used for millennia to build all sort of constructions. As a result, a significant part of the building stock around the world is made of masonry. In the need of structural assessment, structural analysis tools, as well as strength criteria proposed in building codes, require the knowledge of the mechanical properties of the materials. However, the mechanical characterisation of masonry is still difficult and challenging, due to its composite nature and its complex mechanical behaviour. In fact, it is possible to find contradictions among standards, lack of definition for certain procedures, or even lack of standards for certain tests. This thesis aims to contribute with the critical analysis of some of these testing procedures and provide possible improvements for a specific type of masonry. Four lines of research have been identified, which cover tests in laboratory and in situ to characterise the behaviour in compression and in shear. The specific type of masonry on which the experimental campaigns are carried out is the traditional type of brickwork that was extensively used in Barcelona during the 19th and 20th c. In spite of its relevance, this type of masonry is in need of further characterisation. A preliminary research was necessary to find a historical-like mortar with a relatively fast hardening and low mechanical properties. The modification of hydraulic lime based commercial mortars with the addition of limestone filler is investigated. Small amounts of filler enhance the mechanical properties of the mortar. High amounts of filler reduce the mortars’ strengths and make it suitable to replicate historical-like masonry in laboratory. The first line of research on testing procedures covered the compressive characterisation of masonry on prismatic standard specimens. European and American standards differ in the type of specimen to consider, running bond walls and stack bond prisms, respectively. This work compares experimental results obtained from both types of specimen and also obtained from two types of loading, monotonic and cyclic. The second line of research involves an experimental campaign that investigates the possibility of using 90 mm cylinders extracted from existing walls to characterise the compressive behaviour of masonry. Four examples of masonry have been investigated, including cylinders extracted from three existing buildings of Barcelona. The results obtained with 90 mm cylinders compare well to those obtained with the well-known 150 mm cylinders. The third line of research deals with the characterisation of the shear response of masonry in laboratory. The standard triplet specimen consisting of three units and two mortar joints present some interpretation problems related to the non-simultaneous failure of the two joints. This experimental campaign studies the possibility of using couplet specimens of only one mortar joint to determine the shear parameters. For the two types of brickwork investigated, couplets provide higher estimations of the shear parameters with respect to triplets. The last line of research investigates the diagonal compression test, a testing procedure applicable both in situ and in laboratory for shear characterisation. First, an experimental campaign is presented. The experimental results are used to calibrate a numerical model, which is applied to investigate the actual states of stresses and to find correlating coefficients between the test results and the mechanical properties of masonry. The combination of all the former researches provides a set of reference values for the mechanical properties of the traditional brickwork of Barcelona. Nevertheless, the scientific findings, methods, and criteria presented in this thesis, even if derived for a specific type of brickwork, may be of application for the characterisation of other types of masonry around the world.
L’obra de fàbrica ha estat utilitzada durant mil·lennis per construir tota mena d’estructures. Davant la necessitat de verificacions estructurals, les eines d’anàlisi, així com els criteris de resistència dels codis de construcció, requereixen el coneixement de les propietats mecàniques dels materials. Malauradament, la caracterització mecànica de l’obra de fàbrica no es tasca fàcil i continua suposant un desafiament, per la seva natura composta i el seu complex comportament. De fet, és possible trobar contradiccions entre normes, manca de definició per alguns procediments i, inclús, inexistència de normes per alguns tipus de test. Aquesta tesi aspira a contribuir a l’anàlisi crítica d’algunes d’aquestes tècniques d’assaig i proveir-ne possibles millores per a un tipus d’obra de fàbrica específic. Quatre línies de recerca s’han identificat, que abasten tests en laboratori i in situ per caracteritzar el comportament a compressió i a tallant. El tipus específic de material sobre el qual es duran a terme les campanyes experimentals és la fàbrica de maó tradicional que va ser extensament utilitzada a Barcelona durant els segles XIX i XX. Tot i la seva rellevància, aquest tipus de material continua necessitant una caracterització més detallada. Una recerca preliminar fou necessària per trobar un morter pseudo-històric amb febles propietats mecàniques. La modificació de morters comercials de calç hidràulica amb l’addició de filler calís és investigada. Petites quantitats de filler milloren les propietats mecàniques del morter. Majors quantitats de filler redueixen les resistències del morter i el fan apropiat per replicar fàbriques de tipus històric al laboratori. La primera línia de recerca sobre tècniques d’assaig va estudiar la caracterització a compressió amb espècimens prismàtics estàndards. Les normes americanes i europees difereixen en el tipus d’espècimen considerat, prismes apilats i petits murets, respectivament. Aquest treball compara resultats experimentals obtinguts amb els dos tipus d’espècimen i també obtinguts amb dos tipus d’aplicació de càrrega, monòtona i cíclica. La segona línia de recerca desenvolupa una campanya experimental que investiga la possibilitat d’utilitzar cilindres de 90 mm de diàmetre extrets de murs existents per caracteritzar la resposta a compressió. Quatre exemples d’obra de fàbrica s’han investigat, incloent cilindres xvi extrets de tres edificis de Barcelona. Els resultats obtinguts amb els cilindres de 90 mm es comparen satisfactòriament amb els obtinguts amb els ja coneguts cilindres de 150 mm. La tercera línia de recerca tracta la caracterització en laboratori de la resposta a tallant de l’obra de fàbrica. La tripleta estàndard formada per tres maons i dos junts de morter presenta alguns problemes d’interpretació relacionats amb la fallada no simultània dels dos junts. La campanya estudia la possibilitat d’utilitzar bipletes composades de tan sols un junt de morter per determinar els paràmetres a tallant. Pels dos tipus de material estudiats, les bipletes proporcionen majors estimacions de les propietats a tallant que les tripletes. L’última línia de recerca estudia el test de compressió diagonal, una tècnica aplicable in situ i al laboratori per caracteritzar el comportament a tallant. Es presenta una campanya experimental, els resultats de la qual s’utilitzen per calibrar un model numèric. Aquest s’aplica per investigar els estats de tensions reals i trobar coeficients de correlació entre els resultats del test i les propietats mecàniques de l’obra de fàbrica. La combinació de les investigacions prèvies proporciona un conjunt de valors de referència per a les propietats mecàniques de la fàbrica de maó tradicional de Barcelona. Les conclusions científiques, mètodes i criteris presentats en aquesta tesi, tot i haver estat derivats per un tipus específic de fàbrica, poden ser d’aplicació per a la caracterització d’altres tipus de fàbrica arreu del món
La obra de fábrica ha sido utilizada durante milenios para construir toda clase de estructuras. Ante la necesidad de verificaciones estructurales, las herramientas de análisis, así como los criterios de resistencia de los códigos de construcción, requieren el conocimiento de las propiedades mecánicas de los materiales. Desafortunadamente, la caracterización mecánica de la obra de fábrica no es una tarea fácil y continúa suponiendo un desafío, por su naturaleza compuesta y su complejo comportamiento. De hecho, es posible encontrar contradicciones entre normas, falta de definición en algunos procedimientos o, incluso, inexistencia de normas para algunos tipos de test. Esta tesis aspira a contribuir en el análisis crítico de algunas de estas técnicas de ensayo y proveer posibles mejoras en ellas para un tipo de obra de fábrica específico. Se han definido cuatro líneas de investigación que abarcan ensayos en laboratorio e in situ para caracterizar el comportamiento a compresión y a cortante. El tipo específico de material sobre el que se llevan a cabo las campañas experimentales es la fábrica de ladrillo tradicional que se usó extensamente en Barcelona durante los siglos XIX y XX. A pesar de su relevancia, este tipo de material continúa necesitando una caracterización más detallada. Una investigación preliminar fue necesaria para encontrar un mortero pseudo-histórico con débiles propiedades mecánicas. La modificación de morteros comerciales de cal hidráulica con la adición de filler calizo es investigada. Cantidades pequeñas de filler mejoran las propiedades mecánicas del mortero. Mayores cantidades de filler reducen sus resistencias y lo hacen apropiado para replicar obras de fábrica de tipo histórico en el laboratorio. La primera línea de investigación sobre técnicas de ensayo estudió la caracterización a compresión con especímenes prismáticos estandarizados. Las normas americanas y europeas difieren en el tipo de espécimen considerado, prismas apilados y pequeños muretes, respectivamente. Este trabajo compara resultados experimentales obtenidos con los dos tipos de espécimen y también obtenidos con dos tipos de aplicación de carga, monótona y cíclica. La segunda línea de investigación gira sobre una campaña experimental que investiga la posibilidad de utilizar cilindros de 90 mm de diámetro extraídos de muros existentes para caracterizar la respuesta a compresión. Se han investigado 4 ejemplos de fábrica, incluyendo cilindros extraídos de 3 edificios de Barcelona. Los resultados obtenidos con los cilindros de 90 mm se comparan satisfactoriamente con los obtenidos en los ya aceptados cilindros de 150 mm. La tercera línea de investigación trata la caracterización en laboratorio de la respuesta a cortante de la obra de fábrica. La tripleta estándar formada por tres ladrillos y dos juntas de mortero presenta algunos problemas de interpretación relacionados con el fallo no simultáneo de las juntas. La campaña estudia la posibilidad de utilizar bipletas con una sola junta de mortero para determinar los parámetros a cortante. Para los dos tipos de material estudiados, las bipletas proporcionan mayores estimaciones de las propiedades a cortante que las tripletas. La última línea de investigación estudia el ensayo de compresión diagonal, una aplicable in situ y en laboratorio para caracterizar el comportamiento a cortante. Se presenta una campaña experimental cuyos resultados se utilizan para calibrar un modelo numérico. Este se aplica para investigar los estados reales de tensiones y encontrar coeficientes de correlación entre los resultados del ensayo y las propiedades mecánicas de la obra de fábrica. La combinación de las investigaciones previas proporciona un conjunto de valores de referencia para las propiedades mecánicas de la fábrica de ladrillo tradicional de Barcelona. Las conclusiones científicas, métodos y criterios presentados en esta tesis, aun habiendo sido derivados para un tipo específico de fábrica, pueden ser aplicados para la caracterización de otros tipos de fábrica en otras áreas geográficas.

The assessment of historical structures is a significant need for the next generations, as historical monuments represent the community’s identity and have an important cultural value to society. Most of historical structures built by using masonry which is one of the oldest and most common construction materials used in the building sector since the ancient time. Also it is considered a complex material, as it is a composition of brick units and mortar, which affects the structural performance of the building by having different mechanical behaviour with respect to different geometry and qualities given by the components.

Historical monuments are the most invaluable reflections of our architectural heritage and cultural identity, both of which have significant roles to create a strong link between the past and the present. They should be conserved in their own settings with their original characteristics or with as minimum changes as possible. However, natural or man-made hazards cause a serious risk for the survival of historical monuments. While some of them require to be strengthened only, some should be relocated to a new site since there are no means to save them without transporting. In this study, an innovative methodology is developed in a general sense for transporting historical masonry monuments without destructing their unity. In the proposed methodology, which is applicable especially to the slender historical structures, it is aimed to transport the structure by tilting it up to a horizontal ground level without dismantling into pieces. Due to the fact that masonry is a very brittle material, externally located prestressed cables are used to strengthen the structure against tension forces, which occur at the time of tilting. Hasankeyf, which is the cradle of various civilizations, is an impressive medieval city located in Mesopotamia region in Turkey. Unfortunately, this unique heritage will be flooded by the reservoir of Ilisu Dam unless the project is cancelled. Therefore, a masonry minaret located in Hasankeyf is selected as a case for this study. Because of the non-homogeneous characteristics of the structural material, Finite Element Method, as a powerful analytical modeling tool, is used in order to evaluate the validity and effectiveness of the proposed methodology. Finally, it is certified that this methodology is successfully applicable for the relocation of historical masonry monuments.

Ultrasonic Pulse Velocity (UPV) and Rebound test as non-destructive techniques may effectively contribute to in situ analysis of bricks and masonries elements for the restoration, rehabilitation and strengthening of historic buildings. Fired-clay bricks were commonly used in buildings in ancient China, but there is few knowledge on their behaviour in environmental conditions. Moisture is one of the main factors that cause deterioration in historic building, in particular in areas with natural freeze-thaw cycles. In this work, two laboratory experiments were carried out, at Tongji University, China, and DICAM Department of Bologna University, Italy, respectively. Fired-clay bricks about 200 years old were collected from demolished buildings in Changzhi City in Shanxi Province, belonging to the Yellow River Region, where the climate involves natural freeze-thaw cycles. The aim was to evaluate how the frost damage changes the physical and mechanical properties of Chinese historical bricks and masonries. Several non-destructive methods were used, focusing on the effectiveness of Ultrasonic Pulse Velocity (UPV) for evaluating physical and mechanical properties of Chinese historic grey bricks and masonries. Destructive tests were also used to evaluate compressive strength and static elastic modulus. The samples showed a reduction of their properties due to freeze-thaw cycles. The presence of water affected the values of the analysed parameters, leading to a decrease of UPV. The trend determined by these methods can be used to assess the uniformity of bricks and to detect areas of poor quality or deteriorated masonry structures.

The symbolic and historical dimension of the main founding archetypes of Freemasonry – the Orient with a special focus on Egypt – are at the core of this book, which aims to recover the red thread with which masons tie together Masonry and Oriental esotericism. If, on the one hand, the Author points out mystifications and inventions that have characterised part of the Masonic narrative on its origins; on the other hand, she unearths the history of real contaminations and intersections between esotericism of the East and the West, digging up the common matrix that nourished them.

The static and seismic retrofitting design, for masonry historical buildings, has to follow a right hierarchy of interventions, taking into account that to improve the seismic behavior of a masonry structure, it is necessary to guarantee a “closed box” behavior for the whole structural body or, in case of complex buildings, to guarantee a closed box behavior for each building's wing. Thus it is fundamental to distinguish the interventions for the global behavior improvement from those related to local reinforcements. In this chapter is then proposed a scheme of interventions hierarchy and, therefore, a related design process road-map together with the explanation of a correct design philosophy for the static and seismic retrofitting of historical masonry buildings. Moreover it is also reported an example of two distinguished levels of intervention, with numerical analyses supporting that solution.

The static and seismic retrofitting design, for masonry historical buildings, has to follow a right hierarchy of interventions, taking into account that to improve the seismic behavior of a masonry structure, it is necessary to guarantee a “closed box” behavior for the whole structural body or, in case of complex buildings, to guarantee a closed box behavior for each building's wing. Thus it is fundamental to distinguish the interventions for the global behavior improvement from those related to local reinforcements. In this chapter is then proposed a scheme of interventions hierarchy and, therefore, a related design process road-map together with the explanation of a correct design philosophy for the static and seismic retrofitting of historical masonry buildings. Moreover it is also reported an example of two distinguished levels of intervention, with numerical analyses supporting that solution.

Rehabilitation of a historic farmstead originated from 17-18th century is focused on the strengthening and preservation of structures including masonry vaults in existing agricultural buildings and underground corridor near Prague. For specification of the actual strength of masonry and also for the determination of material characteristics, the physically-chemical analysis of mortar was prepared. The estimation of actual masonry strength makes it easier to rebuilt two masonry vaults and also to strengthen existing historical corridor which leaded in the past to the ruins of castle. Principles of ISO 13822 for the assessment of existing structures and CSN 73 0038 is applied for the verification of the reliability level of historical masonry vaults which represent an important aspect of the culture of its period and could be considered to have some heritage value.