Nayanthara De Silva

A neural network approach to assessing building facade maintainability in the tropics

A model was developed to assess the maintainability of façade using neural network techniques. Inputs were derived from comprehensive studies of 570 tall buildings (more than 12 stories) through detailed field evaluation and interviews with professionals in the whole building delivery process. Sensitivity analysis showed that the most significant factors associated with façade maintainability include the system selection, detailing, accessibility and material performance.

Maintainability risks of condominiums in Sri Lanka

Purpose – With increased architectural, design and functional requirements and complexities, maintaining a modern building can easily become a costly affair. There is much evidence in the literature review as well as from the factual data, showing the significant increase of the maintenance budget in the recent past. This is due to the fact that, these complexities eventually generate many deficiencies and difficulties and, in turn, creates a tremendous maintenance workload and an undue budget. Therefore, the purpose of this paper is to discuss factors related to such issues in the form of risks involved in the maintainability of buildings and further, explore several strategies and industry actions at the industry level to resolve this burning problem. This paper is focused to address the condominium properties.Design/methodology/approach – This approach of investigation of the risk factors was based on exploring the causes of existing defects and problems, which tend to lower the maintainability. Existi...

Risk factors affecting building maintenance under tropical conditions

Purpose – The factors contributing to maintenance cost include the life‐long environmental factors that the building is exposed to during its useful life as well as parameters relating to the design, construction and maintenance processes. The performance of risk associated with these factors decides the future maintenance requirements of buildings. Ignoring these risks factors generally result in high maintenance costs. The purpose of this paper is to identify the maintainability risk factors and their implications on maintenance costs.Design/methodology/approach – A survey based methodology was used to establish the risks factors of building maintainability. A sample of high‐rise buildings was selected to evaluate these risk factors that were identified through an extensive literature review and survey of substantive experts. Further, these risks factors were applied to a real case study.Findings – A total of ten risk factors of maintainability were identified in relation to high‐rise buildings. They we...

Use of PC elements for waste minimization in the Sri Lankan construction industry

Purpose – In the construction industry, it is well known that there is a relatively large volume of material being wasted due to a variety of reasons. The problem of material waste on construction sites is not an isolated issue and is of environmental concern. Therefore, waste minimization has become an important issue in the construction industry. The aim of this research was mainly to identify the pre‐cast contribution to the construction waste minimization in the Sri Lankan construction industry, through a comparison of material waste arising from pre‐cast, ready‐mixed and site‐mixed concrete.Design/methodology/approach – Data were collected from 27 building construction projects and three concrete elements: slabs, beams, and columns, were considered to quantify construction waste. To compare the wastage due to pre‐cast involvement with other types, three categories of building projects were used, including projects using pre‐cast concrete elements, in situ concrete elements – site mix, and in‐ situ co...

OSH management framework for workers at construction sites in Sri Lanka

Purpose – This study attempts to identify a simple and efficient framework to be implemented in the Sri Lankan construction industry to inculcate a “safe and healthy” working environment for its workforce.Design/methodology/approach – The occupational safety and health (OSH) management strategies that could be implemented in the construction sites were identified through a comprehensive literature survey and a pilot survey. A questionnaire survey was carried out among the safety and health (S&H) experts to explore the most effective OSH management strategies and thereafter to derive OSH mechanisms to promote the safer and healthy environment in the construction sites. Success of these mechanisms in the local industry was analyzed and was subsequently used to develop the OSH management framework.Findings – A total of 35 significant OSH management strategies, unsafe and unhealthy factors as risk factors for fatal and non‐fatal situations were identified. A further ten OSH management mechanisms were establis...

Maintainability of wet areas of non‐residential buildings

This paper discusses some important findings from a research project on the maintainability of wet areas of high‐rise non‐residential, buildings. The implications of six key factors of maintainability namely water‐tightness, spatial, integrity, ventilation, material and plumbing on the occurrence of 14 most common defects found in wet areas were evaluated. Problem areas evaluated include water leakage from ceiling, staining/discolouration, paint defects, cracking/spalling of concrete, cracking/debonding of tiles, fungi/algae growth, pipe leakage and corrosion. An industry wide survey was conducted and the factors including workmanship, design detailing, maintenance and material incompatibility under tropical conditions are identified and discussed.

Factors Affecting Water-Tightness in Wet Areas of High-Rise Residential Buildings

Defects related to internal water leakage in wet areas of 1500 high-rise residential building blocks between 0–35 years of age were studied. The problem type, the extent of the problem, the mechanism, the implications of design; construction material and maintenance, and the local and international standards; codes of practices; good practice guides etc governing the aspects were discussed. The study highlights the significance of ensuring close interaction right from the planning and design phases between professionals including the maintenance team. The cases presented show the importance of reviewing structural, architectural and M&E issues using an integrated approach throughout the whole building delivery process.

Benchmarks to minimize water leakages in basements

Basement defects such as water seepages/leakages are tedious and expensive to rectify. Intensive research has been conducted to study the problem type, their causes and preventive measures. The study explored 987 water seepage/leakage cases in 61 buildings. Eleven significant factors leading to the occurrence of water seepage in basements were identified. The implications of six benchmarks, namely: degree of water‐tightness; safety measures for structural concrete; performance of waterproofing systems; integrity of basement structure; provision for movement and quality of compaction in concreting, for minimizing four types of water seepage/leakage problems in basements are discussed.

Artificial Neural Network Approach for Grading of Maintainability in Wet Areas of High-Rise Buildings

A grading system using artificial neural networks to enhance decision-making of wet area design was developed. The model was derived from condition survey of 450 tall buildings and in-depth assessment of a further 120 tall buildings and interviews with the relevant building professionals. The system allows comparison of various alternative designs, materials, construction and maintenance practices, so as to achieve optimum solutions of technical attributes that lead to minimum life cycle maintenance cost.

Risk analysis in maintainability of high-rise buildings under tropical conditions using ensemble neural network

Purpose – The aim of this research study is to develop a risk-based framework that can quantify maintainability to forecast future maintainability of a building at early stages as a decision tool to minimize increase of maintenance cost. Design/methodology/approach – A survey-based approach was used to explore the risk factors in the domain of maintainability risks under tropical environmental conditions. The research derived ten risk factors based on 58 identified causes related to maintainability issues as common to high-rise buildings in tropical conditions. Impact of these risk factors was evaluated using an indicator referred to as the “maintenance score (MS)” which was derived from the “whole-life maintenance cost” involved in maintaining the expected “performance” level of the building. Further, an ensemble neural network (ENN) model was developed to model the MS for evaluating maintainability risks in high-rise buildings. Findings – Results showed that predictions from the model were highly compat...