摘要:

Many offshore structures are subjected to overturning moments due to wind load, wave pressure, and ship impacts. For foundations in such structures, usually a combination of vertical and batter piles is used. Little information is available in the literature about estimating the capacity of piles under uplift. In cases where these supporting piles are not vertical, the behavior under vertical pullout is not well established. In this article the vertical pullout behavior of batter piles is examined through an experimental investigation carried out on model batter anchor piles. The tests are conducted on model aluminum pipe piles of 19 mm diameter with different embedment ratios in a soft marine clayey bed at different consistencies and with various batter angles of 0°, 10°, 20°, and 30°. Results indicate that the pullout capacity of a batter pile is less than that of a vertical pile. This reduction is explained in terms of reduced area available for skin friction. Based on this, pullout behavior of batter anchor piles is described as “short anchor” and “long anchor” failures. However, with increase in the embedment length, the capacity of batter pile remains unaffected.

ISSN:1064-119X    

DOI:10.1080/10641199609388312

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

For anchoring tension leg platforms (TLPs) to the seabed, several new anchoring systems are being developed. The superpile anchoring system is one such new system. This article presents the results of laboratory tests to investigate the suitability of superpile anchors as foundations of TLPs in soft clays. The pullout load‐displacement behavior under static loading of model superpiles embedded in soft clay was studied and compared with that of similar large‐diameter piles having open tops.

ISSN:1064-119X    

DOI:10.1080/10641199609388313

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

On January 17, 1995, a severe earthquake struck Kobe City and surrounding regions. The earthquake caused extensive damage to building, lifeline systems, transportation, and port facilities, including large‐scale earth structures, e.g., man‐made islands.

ISSN:1064-119X    

DOI:10.1080/10641199609388314

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

Many ground improvement techniques have been developed for the safe support of structures constructed on weak ground. The sand drain method is an easy‐to‐design, highly economical method of ground improvement using the principle of accelerated consolidation, which has been used successfully many times for structures of various sizes and types. Kansai International Airport was constructed on a man‐made island that was formed by land reclamation in deep water, 33 m thick, on a soft seabed. The sand drain method was carried out in a 20‐m layer of alluvial clay, and using the results of soil investigation and the monitoring of behavior of the ground, analyses were performed on ground settlement and strength improvement These methods were effective in reducing residual and uneven settlement and preventing the sliding of the seawall

ISSN:1064-119X    

DOI:10.1080/10641199609388315

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

This article describes the mineralogy, chemistry, and geotechnical properties of quick and nonquick clay profiles in Ariake Bay, Japan, and the correlations of the mineralogy and chemistry of the clays with their geotechnical properties. The chemistry is discussed in terms of saline environment at the time of deposition, and postdepositional weathering processes. The principal clay minerals identified were smectite, mica, and kaolinite. The salinity in pore water of nonquick clay varied, according to changes in sea level, from brackish to marine, and then brackish toward the surface. The higher iron oxide contents of the clay profiles were attributed to the production of iron hydroxide by pyrite oxidation, due to exposure of the clays to atmosphere for the nonquick clay sediment, and due to the supply of oxygen from fresh water permeating through the clays during leaching process for the quick clay sediment. The major factors which increase the activity of the clay were both smectite and salinity in pore water for the nonquick clay, and smectite for the quick clay. The greater Cu/p values of the clays were associated with the higher iron oxide contents. There was a negative correlation between the sensitivity and salinity in pore water, and a positive correlation between the sensitivity and liquidity index for the combined data on quick and nonquick clays. The compression index of undisturbed clays was found to be represented as a function of the liquid limit and sensitivity.

ISSN:1064-119X    

DOI:10.1080/10641199609388316

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

Sampling methods for marine soft clay in Japan are presented. Two types of sampling methods are employed in the routine investigation: the core tube method and the drilling pipe method. To collect high‐quality samples, a thin‐wall tube sampler with a fixed piston, whose specification is strictly defined by the Japanese Geotechnical Society, should be used for soft cohesive soils. In addition to the conventional sampling method, three newly developed sampling techniques are introduced: the Marine Auto Sampler, a wire line‐type sampler, and a Laval‐type sampler.

ISSN:1064-119X    

DOI:10.1080/10641199609388317

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

ISSN:1064-119X    

DOI:10.1080/10641199609388311

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor