Technical and Structural Problems Related to the Interaction between a Deep Excavation and Adjacent Existing Buildings

Abstract

Currently, new housing in city centers is more and more often developed on small plots of land, or existing buildings on such plots are rebuilt to such an extent that only their façade walls remain. In both cases, as a rule, a deep excavation is also made, either at the existing object or within its area. Serious damage often occurs because of the carried out work. It is not possible to accurately determine the response of a building to the deformation associated with the excavation due to the variability of many factors that influence it. As a result, the response of the building must be estimated on the basis of constant monitoring and approximate calculations. Depending on the size of the predicted ground displacements and the technical condition of buildings, it is often necessary to protect or strengthen their structural elements. In the paper, the authors analyzed various risk factors for the implementation of infill buildings and the revitalization of historic buildings using only their façade walls. In addition, examples of contemporary solutions for securing the walls of existing buildings, and the method of monitoring vertical deformations using the Hydrostatic Levelling Cell (HLC) system, are presented.

Application and Automatic Monitoring and Analysis of Hybrid Support Structure in Ultra-DEEP Foundation Pit Engineering in the Lanzhou Area under Complex Environmental Conditions

“…The maximum excavation depth of the foundation pit of this project is about 22.3 m, and the lithology of the site strata within the proposed site is composed of the fourth series of new artificial fill and alluvium, which is divided into 6 main engineering geological layers and 4 engineering sublayers according to its engineering geological characteristics, which are now described as follows: 1 Miscellaneous fill (Q 4 ml ): variegated, slightly wet, loose, uneven soil quality, the surface layer of 0.10~0.20 m is mostly concrete ground, the overall backfill is uneven, irregular, the backfill contains silt, bricks, concrete blocks, white ash, gravel, Coal ash and dark impurities, etc. 2 Plain fill (Q 4 ml ): yellow-brown, slightly wet, slightly dense, mainly backfill silt, containing a small amount of gravel, construction waste, etc.…”

“…Dmochowski, G. et al [1] analyse various risk factors for the implementation of infill buildings and the revival of historic buildings using only facades. In addition, examples of modern solutions for fixing existing building walls are presented, as well as methods for monitoring vertical deformations using a hydrostatic level (HLC) system.…”

Comparative analysis of an anchored retaining wall system in a deep foundation excavation: A case study of Sivas Cultural Center Building in Türkiye

“…They stated that it is impossible to accurately determine a structure's response to excavation-related deformation due to the variability of many factors affecting horizontal and vertical deformations in structures. The article analyzed the various risk factors that cause deformations by monitoring the historic building [6]. Consequently, the structure's deformations must be estimated based on continuous monitoring and approximate calculations.…”

Testing Crack Resistance of Non-Load-Bearing Ceramic Walls with Door Openings

“…The appearance of cracks in partition walls with deflection of supporting floors is considered in standards as exceeding the limit condition of their usability [13][14][15][16]. Regulations concerning the limits of deflections in structures constituting support under masonry walls are often available in standards concerning the design of reinforced concrete structures, and more rarely, in standards concerning masonry structures.…”

“…The requirements included in the standards [17][18][19][20][21][22][23][24] regarding the impact of building structure on non-load-bearing walls provide different permissible values for ceiling slab deflections. The reference documents do not fully describe the impact of the location of door openings in relation to the length of the walls, the conditions of the slab support, and the conditions of contact between the wall and the surrounding structures on their cracking resistance [10][11][12][13][14][15][16]26,27]. Therefore, research on the behavior of partition walls on flexible supports is still necessary.…”