RESPONSE OF UNREINFORCED MASONRY BUILDINGS

Abstract

A summary of dynamic measurements are presented that illustrate relations between linear seismic demand and true nonlinear response of unreinforced masonry buildings with flexible diaphragms and rocking piers subjected to a series of simulated earthquake motions.     

江苏镇江东晋画像砖墓的渊源和意义补论

江苏镇江东晋画像砖发掘简报曾从历史背景出发,简略指出镇江东晋墓兼具山东和先秦楚文化特点。在简报认识的基础上,再补充若干重要实例并进行分析,可以发现六朝时期今镇江地区自成文化圈,镇江东晋画像砖墓是观察汉晋文化嬗变之迹的典型材料。     

江苏淮安如意里唐井发掘简报

2009年4月,楚州博物馆在淮安如意里小区抢救性发掘了一口唐代砖井(编号J1),共出土可复原器物63件,包括大量瓷器、带"汲"字铭文的铜壶以及刀、钩、矛等铁质兵器。该井结构奇特,腹径巨大,在淮安地区尚属首次发现。     

Discrete Element Analysis of the Minimum Thickness of Oval Masonry Domes

This study focuses on domes the ground plan of which, instead of the more common circular shape, is an oval, and aims at finding the minimally necessary uniform wall thickness for domes of different geometries loaded by their selfweight. The discrete element code 3DEC was applied because of its capability of simulating the collapse mechanisms of masonry structures. Results on the minimal wall thickness, corresponding masonry volume and failure mechanisms for different dome geometries are presented. Three ranges of the friction coefficient were found. For very low frictional resistance collapse happens with pure frictional sliding, for any arbitrarily large wall thickness. In the range of relatively high (i.e., realistic) friction coefficients the structure collapses without any sliding if the wall is not sufficiently thick, and in the observed range of the friction coefficient the necessary wall thickness is nearly insensitive to its value (collapse initiates with hinging cracks only). Between the two domains an intermediate behavior was found: combined cracking and sliding collapse modes occur for insufficient wall thickness, and the minimal thickness strongly depends on the friction coefficient. The critical and transitional friction coefficients separating the failure modes were determined for different eccentricities of the groundplan.     

Report on the first research campaign on the Napoleonic brick, Mercure, wrecked off Lignano, Udine, Italy in 1812

During 2001, the NAUSICAA office organized a research campaign on the site where two carronades had been retrieved by a fishing boat. Side-scan sonar research led to the discovery of a mound and six more carronades. The mound was composed of iron ingots, cannon balls, and tools reused as ballast. After the cleaning of a carronade, it was possible to read the name of the foundry, Du Creusot , and the date, 1806. This evidence was sufficient to identify this as the wreck of the Napoleonic brick, Mercure , lost during the Battle of Grado, fought between an English and French fleet in February 1812.     

建康及外围地区六朝大型砖室墓之建筑结构和筑造技术

本文系统论述了六朝时期建康及外围地区大型砖窑墓的建筑结构和筑造技术,认为这一时期墓葬非常富有地域特色,并传之于隋唐。     

高平市汤王头村砖雕壁画墓结构形制研究

本文对山西高平汤王头村砖雕壁画墓的结构形制进行分析研究。通过形制特征排比,作者推断该墓年代在金代大定至明昌时期,并认为以其为代表的晋城地区金墓,体现出了仿木构形制与技术沿交通线传播的历史进程。通过实测尺度分析,确认墓主室平面、立面采用整尺设计,后室、侧室平面以条砖尺寸为模数性基准。墓室仿木斗栱用预制模件装配而成,主室斗栱表现出明显模拟木构斗栱"材分制"的做法。     

江苏徐州睢宁龙头山明墓发掘报告

2013年3月,徐州博物馆和睢宁博物馆对位于江苏省徐州市睢宁县官山镇西北约10公里的龙头山明墓进行了抢救性发掘。该墓为一座仿木结构砖室墓葬,由墓道、门楼、甬道、前室、石门、后室组成。该墓有仿木构的门楼和庭院式的前后室,门楼和墓室有丰富多彩的砖雕和彩绘壁画,石门上有阴刻描金题记"看破四大满腔念头归衣钵"和"万历二十三年四月望日立",为研究明代葬制、葬俗、建筑、绘画、宗教等提供了珍贵的资料。     

A Comparative Study on the Compressive Strength of Bricks from Different Historical Periods

The aim of this article is to present the results of compressive strength tests for bricks from different historical periods. The studies were conducted on hand-molded and mechanically formed bricks. The bricks that were used for the studies came from historical structures from the center of the royal city of Crakow. Compressive strength was determined on rectangular prisms and on cylinders cut out from bricks in various directions—anisotropy and shape effects were then analyzed.

?The basic aim of the conducted studies was to estimate the possibility of carrying out the strength tests on relatively small samples and re-calculating these results on normalized brick strength determined according to EN772–1. Based on the tests results, a range of correlation coefficient values for cylinder samples with diameters of 30 mm and 50 mm was given. It was indicated that for the tested historical bricks characterized by significant material non-homogeneity within the element and sensitivity to damages while cutting out the samples, correlation coefficients are higher than for bricks used contemporarily.

?The results of these studies are presented alongside the findings from existing studies on the compressive strength of bricks.     

Material Characterization and Micro-Modeling of a Historic Brick Masonry Pillar

A masonry pillar composed of solid clay bricks, cement mortar and infill is extracted from a historical structure and tested in concentric compression. It is subjected to cyclic and monotonic loads up to compressive failure.

In parallel, samples are extracted from the pillar and are subjected to destructive tests. Non-destructive tests are performed on the pillar, as well. The properties of the constituent materials are critically examined and their role in the maximum load reached and the failure mode obtained are discussed.

Finally, a finite element micro-model of the pillar is used for the simulation of the pillar test. The influence of the existing damage on the pillar is investigated using the model, resulting in a fair approximation of the global Young’s modulus, maximum load and the failure mode.

Highlights

●?A brick masonry pillar extracted from a historical building is tested in compression.

●?Material samples extracted from the pillar are characterized by mechanical tests.

●?A finite element micro-model of the pillar is used for the simulation of the compressive test.

●?The effect of damage on the compressive strength of the pillar is numerically investigated.