ENGINEERING EVALUATION OF THE 1 OCTOBER 1995 DİNAR EARTHQUAKE (ML = 5.9)

In 1995, a swarm of earthquakes affected the city of Dinar, Turkey, which is located in Southwest Anatolia and has a population of 35 000. The mainshock having a local magnitude of 5.9 occurred on 1 October 1995. It was preceded by foreshocks in the previous four days, the largest one with a magnitude of 4.7. These foreshocks initiated structural damage in many buildings, which was then severely aggravated by the mainshock and a strong aftershock two hours later, with a magnitude of 5.0. Numerous aftershocks were recorded throughout the following three months. Strong ground motions were recorded within the city. The mainshock produced peak horizontal accelerations of 0.28 g and 0.29 g. The Dinar earthquake caused a death toll of 92 and more than 200 injuries. The economic losses due to structural damage alone are estimated at 250 million USD.     

EXPERIMENTAL ASSESSMENT OF THE GLOBAL CYCLIC DAMAGE OF FRAMED R/C STRUCTURES

It is accepted that failure criteria for earthquake-resistant structures should be based on energy dissipation as well as on maximum ductility. Even though rational procedures to include low-cycle fatigue in the definition of the design spectra have been derived, major difficulties arise in the definition of the cyclic damageability of the structure. The work conducted so far was mainly based on cyclic tests conducted on simple structural elements, therefore, the extension to the complete structure is not an easy task. A final cyclic test was conducted at the ELSA reaction wall facility on a four-storey full-scale reinforced concrete frame designed according to Eurocode 8, at the end of a series of pseudodynamic tests. The results allow the performance during the pseudodynamic tests to be assessed and the cyclic damageability of a complete structure to be investigated. The effects of low-cycle fatigue on a high-ductility structure turned out to be more important than expected.     

DUCTILITY AND LOAD CARRYING CAPACITY PREDICTION OF STEEL BEAM-TO-COLUMN CONNECTIONS UNDER CYCLIC REVERSAL LOADING

Abstract

The economy and reliability of steel-framed buildings in seismic areas depend basically on the hysteretic behaviour of its individual components, such as members and joints. With reference to the latter, despite the recent semi-continuous frame approach (which appears generally very convenient for the design of low- and medium-rise steel buildings), the present state of knowledge does not allow for a complete understanding of the behaviour and the low-cycle fatigue life of beam-to-column connections under dynamic loads.

This paper presents a criterion for the definition of the low-cycle fatigue strength of steel connections, and proposes two approaches for the design of steel frames in seismic zones via the assessment of the fatigue damage, which is evaluated alternatively on the basis of either the ductility or of the load carrying capacity.     

Under Pressure: A Laboratory Investigation into the Effects of Mechanical Loading on Charred Organic Matter in Archaeological Sites

The present publication investigates what happens to archaeological sites when they are built over. Focus is put on the degradation of charred organic materials by static loading. It is assumed that materials lose archaeological value if their fragments become too small to be recovered, or too distorted to be classified at species level. Several charred ecofacts of a few millimetres in size (wood fragments, hazelnut shells, and seeds) have been selected and subjected to individual particle strength tests. Assemblages of these particles have also been compressed one-dimensionally and scanned at several stages of testing using laboratory based X-ray microtomography. Microscopic damage by splitting or crushing is found to be limited at the macroscopic yield stress. It initiated at stresses less than 80 kPa for the weakest assemblages, and in all cases at stresses below 320 kPa. (80 kPa represents the load of a 6 m high sand embankment on soft soil that has half-settled underneath the groundwater table, while 320 kPa corresponds to stresses applied beneath the pile foundation level of high-rise buildings.) Sand seeded with charred particles has also been tested to illustrate the beneficial effect of embedment of charred particles in sand during static one dimensional loading.     

明矾在纸质文物中的应用研究

纸张酸化是一个世界性问题．本文从引起酸化的一个方面一明矾添加物入手,较全面的阐述了其在纸质文物中的应用．并根据机理分析了明矾的作用特．点以及对纸质文物的影响。明矾除了具有沉淀胶料和防腐防蠹的特点,还能起到媒染剂的作用,但其水解后呈酸性,对纸质文物有潜在的酸化危害。     

Assessing the Impact of Typhoons on Historic Iron Shipwrecks in Chuuk Lagoon Through Changes in the Corrosion Microenvironment

The corrosion microenvironment of a dozen Second World War iron shipwrecks in Chuuk Lagoon, Federated States of Micronesia, was investigated to see if there were any measurable changes caused by a recent major typhoon. Seven previously inspected wreck sites were used for calibration to assess the environmental impacts. Five new wrecks, including the Fumitzuki, a destroyer of the Imperial Japanese Navy, were assessed at up to twice the depth of previous studies. The new data showed that the logarithm of the corrosion rate falls linearly with depth to 36 m. Measurements of corrosion potentials, concretion thickness and pH showed that many of the vessels suffered partial deconcretion during the typhoon Maysak in April 2015 with concomitant increases in the rate of decay. Regrowth of the colonising marine organisms are presently ameliorating the impact of the typhoon.     

The Battle of Saipan in Japanese Civilian Memoirs: Non-combatants,Soldiers and the Complexities of Surrender

In Japan, ‘Saipan’ refers both to a nearby tropical holiday, and to the site of a battle that annihilated Japanese troops, embroiled the large population of Japanese residents on the island and ultimately spelled the end of the Japanese empire, now within the reach of bombers. In other places, and particularly amongst the Allies, Saipan conjures up images of civilians jumping to their death rather than facing capture, leading to simplistic assessments about fanaticism being rife across all sections of Japanese society; to a focus on suicide that overshadows the true extent of the battle’s collateral damage; and to largely unexamined statements about military exploitation of civilians and the murder of civilians in extremis. This article uses the memoirs of civilian survivors of the battle to reflect on the civilian experience of the battle of Saipan, relationships between Japanese combatants and non-combatants during the fighting, and the complexities of surrender.     

Stress‐dependent transport properties of fractured arkosic sandstone

We measure the fluid transport properties of microfractures and macrofractures in low‐porosity polyphase sandstone and investigate the controls of in situ stress state on fluid flow conduits in fractured rock. For this study, the permeability and porosity of the Punchbowl Formation sandstone, a hydrothermally altered arkosic sandstone, were measured and mapped in stress space under intact, microfractured, and macrofractured deformation states. In contrast to crystalline and other sedimentary rocks, the distributed intragranular and grain‐boundary microfracturing that precedes macroscopic fracture formation has little effect on the fluid transport properties. The permeability and porosity of microfractured and intact sandstone depend strongly on mean stress and are relatively insensitive to differential stress and proximity to the frictional sliding envelope. Porosity variations occur by elastic pore closure with intergranular sliding and pore collapse caused by microfracturing along weakly cemented grain contacts. The macroscopic fractured samples are best described as a two‐component system consisting (i) a tabular fracture with a 0.5‐mm‐thick gouge zone bounded by 1 mm thick zones of concentrated transgranular and intragranular microfractures and (ii) damaged sandstone. Using bulk porosity and permeability measurements and finite element methods models, we show that the tabular fracture is at least two orders of magnitude more permeable than the host rock at mean stresses up to 90 MPa. Further, we show that the tabular fracture zone dilates as the stress state approaches the friction envelope resulting in up to a three order of magnitude increase in fracture permeability. These results indicate that the enhanced and stress‐sensitive permeability in fault damage zones and sedimentary basins composed of arkosic sandstones will be controlled by the distribution of macroscopic fractures rather than microfractures.     

Analysis of the Effect of Provisional Ties on the Construction and Current Deformation of Mallorca Cathedral

This article presents the analysis of the structure of Mallorca Cathedral taking into account the influence on the structural behavior of auxiliary iron ties used during the construction process. Recent studies (Roca et al. 2012, 2013) presented some hypotheses about the construction process of the cathedral. This article complements the previous results by considering the use of auxiliary ties as temporary stabilizing device during the construction. Evidence of the use of ties during the construction has been recognized after a comprehensive survey. The study of the role of such ties and the effect of their later removal are studied by a FE analysis carried out on a representative bay of the structure. The study includes a time-dependent FE analysis after the removal of the ties to assess the long-term structural behavior. The results of the numerical analysis are compared with the deformation trends identified by means of a recent monitoring campaign.     

An innovative methodology of assessing the climate change impact on cultural heritage

Climate change is expected to have a severe impact on cultural heritage in the future. This study presents the methodology developed during the FP7 project Climate for Culture, of assessing the climate change impact on collection objects in cultural heritage buildings. The main innovation lies in coupling new high resolution future climate projections with building simulation tools in order to predict future indoor climate and identify future risks in historic buildings. The case study is an intermittently heated wooden chapel in Croatia. The whole building simulation model of the chapel was validated using a newly developed method of accuracy assessment in the context of preventive conservation. Even though modeling intermittent heating induces limitations in the model, it can be used for computing of future indoor data. Future indoor climate data was assessed for possible risks of biological, mechanical, and chemical damage to painted wooden panels using the newly developed specific climate risk assessment. When using this method of damage assessment on buildings with active climate control, especially with intermittent heating, it is recommended to determine the relevant season for the damage process in order to objectively analyze results.