Foundation Movement and Remedial Underpinning in Low-Rise Buildings

Part 1 Introduction: background; the survey; growth in remedial underpinning; necessity for remedial underpinning; types of building requiring underpinning; distribution of underpinning in the United Kingdom; the cost of remedial underpinning; guarantees; partial underpinning; approval of underpinning designs. Part 2 Causes of damage: introduction; causes of structural damage unrelated to foundations and subsoils - thermal effects, creep, moisture movements, loading on structural members, physical and chemical changes, vibration, poor detail design, poor workmanship and materials, modern materials, techniques and designs; causes of structural damage related to foundations and subsoils - foundation settlement, foundation subsidence, foundation heave, instability of sloping ground, chemical effects, frost heave, floor slab movements. Part 3 Determining the significance of damage: initial assessment; assessing the severity of cracking and damage; identifying type of movement from crack and deformation surveys - general, tapered cracks, inclined cracks, vertical cracks, horizontal cracks, sloping lintels, bulges, separation of walls, out-of-plumb walls, floor slopes, movement of brickwork at dpc level, overall movement; diagnosis of cause of movement and damage; significance of damage. Part 4 Progressive foundation movements: general; site investigation to establish cause; monitoring; assessing the likelihood of progressive foundation movement in relation to cause - settlement, subsidence, heave, instability of sloping ground, chemical attack. Part 5 Site investigations to establish cause of damage and to design underpinning: general; current practice; desk studies; walk-over survey; investigation of existing foundations; ground investigation. Part 6 Arresting progressive foundation movement: general; removal of trees causing subsidence; structural measures; soil stabilization; ground freezing; underpinning; alternatives to arresting movement; reinstatement of damage. Part 7 Remedial underpinning techniques: general; mass concrete underpinning - principle, applications, design, specification, construction and supervision, example of the use of mass concrete underpinning; beam-and-pier underpinning - principle, applications, design, specification, construction and supervision, example of the use of beam-and-pier underpinning; beam-and-pile underpinning - principle, applications, design, specification, construction and supervision, example of the use of beam-and-pile underpinning; underpinning with piles - principle, applications, design, specification, construction and supervision, example of the use of pile underpinning; pali radice (root piles) underpinning; usage of each method; failed underpinning.