"Stone and Timber Cirlces in Britain and adjacent Countries" Review article of Burl, A. 2000 The Stone Circles of the British Isles. (Yale UP), Gibson, A.2000 Stonehenge and Timber Circles (Tempus). and Pitts, M. 2000. Hengeworld. (Century)

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Preaching to Princes: John Burgess and George Hakewill in the Royal Pulpit

This article examines a previously unnoticed link between the Puritan John Burgess and the Calvinist conformist George Hakewill. In 1604 Burgess preached a court sermon so outspoken and critical of James I’s religious policy that he was imprisoned. Nearly twenty years later, however, Hakewill chose to incorporate extended passages from Burgess’s sermon into the series of sermons, King David’s vow (1621), preached to Prince Charles’s household. This article considers why Burgess’s sermon became so resonant for Hakewill in the early 1620s and also demonstrates how Hakewill deliberately sought to moderate Burgess’s strident polemic. In so doing the article provides important new evidence for the politically attuned sermon culture at Prince Charles’s court in the early 1620s and also suggests how, as the parameters for clerical conformity shifted in the latter years of James’s reign, Calvinist conformists found a new appeal in the works of moderate Puritans. I

The settlement performance of stone column foundations

Vibrated stone columns are frequently used as a method of reinforcing soft ground as they provide increased bearing capacity and reduce foundation settlements. Their performance in relation to bearing capacity is well documented, but there is also a need for enhanced understanding of their settlement characteristics, particularly in relation to small-group configurations. This paper presents results obtained from physical model tests on triaxial specimens 300 mm in diameter and 400 mm high. Parameters investigated include column length to diameter ratio, area replacement ratio and single/group configuration. The findings of the work are as follows. The design is flexible: settlement can equally be controlled using short columns at relatively high area replacement ratios, or longer columns at smaller area replacement ratios. An optimum area replacement ratio of 30-40% exists for the control of settlement. The settlement performance of a small column group is highly influenced by inter-column and footing interaction effects.

The pressure distribution along the stone column in soft clay when subjected to consolidation and foundation loading

The mechanism whereby the foundation loading is transmitted through stone the column (included in soft clay) has received less attention from researchers. This paper reports on some interesting findings obtained from a laboratory-based model study in respect of this issue. The stone column, included in the soft clay bed was subjected to foundation loading under drained conditions. The results show, probably for the first time, how the foundation loadings are transmitted through the column and indeed the existence of “negative skin friction” (a widely accepted phenomena in solid piles) in granular columns in soft clays.

"Producers and Consumers in EU E-Commerce Law by John Dickie, Oxford: Hart Publishing, 2005 (ISBN 1-841-13454-6)"

Book Review

Exploitation of inherited weakness in fire-damaged building sandstone: the ‘fatiguing’ of ‘shocked’ stone

The problem of the long-term impact of historical fire on masonry is not clearly understood. Much research focuses on the damage that is caused by fire in isolation, and omits to investigate the subsequent exploitation of weaknesses inherited from fire events. Fire can, for example, cause significant physical, chemical and mineralogical change to sandstone, which may then be exploited by background environmental factors such as salt and freeze–thaw weathering. To explore this experimentally, blocks of Peakmoor Sandstone were subjected to a real fire (as well as lime rendering/removal and frost cycle pre-treatments), and their subsequent response to salt weathering cycles was monitored by weight loss and visual assessment of the pattern of surface damage. Results illustrate that the post-fire deterioration of sandstone is strongly conditioned by fracture networks and soot cover inherited from the fire. The exploitation of fractures can lead to spalling during salt weathering cycles — this takes place as granular dissagregation steadily widens cracks and salts concentrate and crystallise in areas of inherited weakness. Soot cover can have a profound effect on subsequent performance. It reduces surface permeability and can be hydrophobic in character, limiting salt ingress and suppressing decay in the short term. However, as salt crystals concentrate under the soot crust, detachment of this layer can occur, exposing fire-damaged stone beneath. Understanding the subsequent exploitation of stone exposed to fire damage by background environmental factors (for example, salt weathering/ temperature cycling) is key to the post-fire management of stone decay.

A commentary on climate change, stone decay dynamics and the ‘greening’ of natural stone buildings: new perspectives on ‘deep wetting’

Environmental controls on stone decay processes are rapidly changing as a result of changing climate. UKCP09 projections for the 2020s (2010–2039) indicate that over much of the UK seasonality of precipitation will increase. Summer dryness and winter wetness are both set to increase, the latter linked to projected precipitation increases in autumn and spring months. If so, this could increase the time that stone structures remain wet and possibly the depth of moisture penetration, and it appears that building stone in Northern Ireland has already responded through an increased incidence of algal ‘greening’.This paper highlights the need for understanding the effects of climate change through a series of studies of largely sandstone structures. Current and projected climatic trends are therefore considered to have aesthetic, physical and chemical implications that are not currently built into our models of sandstone decay, especially with respect to the role played by deep-seated wetness on sandstone deterioration and decay progression and the feedbacks associated with, for example surface algal growth. In particular,it is proposed that algal biofilms will aid moisture retention and further facilitate moisture and dissolved salt penetration to depth. Thus, whilst the outer surface of stone may continue to experience frequent wetting and drying associated with individual precipitation events, the latter is less likely to be complete, and the interiors of building blocks may only experience wetting/drying in response to seasonal cycling. A possible consequence of deeper salt penetration could be a delay in the onset of surface deterioration,but more rapid and effective retreat once it commences as decay mechanisms ‘tap into a reservoir of deep salt’.

Understanding the decay of stone-built heritage

The problem of the decay and conservation of stone-built heritage is a complex one, requiring input across many disciplines to identify appropriate remedial steps and management strategies. Over the past few decades, earth scientists have brought a unique perspective to this challenging area, drawing on traditions and knowledge obtained from research into landscape development and the natural environment. This paper reviews the crucial themes that have arisen particularly, although not exclusively, from the work of physical geographers — themes that have sought to correct common misconceptions held by the public, as well as those directly engaged in construction and conservation, regarding the nature, causes and controls of building stone decay. It also looks to the future, suggesting how the behaviour of building stones (and hence the work of stone decay scientists) might alter in response to the looming challenge of climate change.