Mix-Design and Application of Hydraulic Grouts for Masonry Strengthening

Preface
Acknowledgements
Contents
Notations
1 Introduction
	1.1 The Significance of the Subject
	1.2 Categories of Grouts for Masonries
	1.3 Basic Data Influencing the Design of a Masonry Grout
	1.4 Main Performances of a Hydraulic Grout
	1.5 Design Procedure
	1.6 Practical Guidance for In-Situ Grouting Application Methodology
	References
2 Penetrability
	2.1 Introduction
	2.2 Literature Survey
		2.2.1 Significance of Penetrability and Relevant Tests for Its Control
		2.2.2 Maximum Grain Size Criterion
		2.2.3 Criterion for the Grading of the Coarser Grains
		2.2.4 Means to Improve Penetrability
	2.3 Simplified Model and Additional Experimental Data
	2.4 Calibration
	2.5 Practical Means to Improve Penetrability of Hydraulic Grouts
		2.5.1 A Simple Analytical Model
		2.5.2 Experimental Verification
	2.6 Conclusions Regarding the Penetrability Grading Criteria for the Grout’s Solid Phase
	2.7 Estimation of a Wnom-value
	References
3 Fluidity
	3.1 Introduction
	3.2 Literature Survey
		3.2.1 Significance of Fluidity
		3.2.2 Relevant Tests for the Control of Fluidity (The Flow Cone Test)
		3.2.3 Fluidity Factor Test (FFT)
	3.3 Further Significance of the Concept of Fluidity Factor—Acceptable Lower Fluidity Factor Values
	3.4 Effects of Mixing Method on Fluidity
	3.5 Effect of Superplasticizers
	3.6 A Case Study of Practical Use of the Fluidity Factor
	3.7 Conclusions
	References
4 Stability
	4.1 Introduction
	4.2 Literature Survey
		4.2.1 Main Parameters Influencing Stability
		4.2.2 Main Tests to Measure Stability
	4.3 An Oversimplified Predictive Model of Bleeding
	4.4 Experimental Investigation on Bleeding
		4.4.1 Bleeding of Grouts Without Added Superplasticizer
		4.4.2 The Role of Superplasticizers
	4.5 Segregation
		4.5.1 In-Time Modification of Grading of an Unstable Grout
		4.5.2 In-Space Differentiation of Grading
		4.5.3 A Simple Analytical Model
		4.5.4 Practical Criterion of Segregability
		4.5.5 Cohesiveness Index
	4.6 Conclusions
	References
5 Guidelines for the Estimation of Wnom
	5.1 Introduction
	5.2 Information on Existing Internal Discontinuities
	5.3 Quantification Attempts
	5.4 Practical Approach
	References
6 Strength-Related Data of Grouts
	6.1 Introduction
	6.2 In Situ Modifications of the Grout After the Injection
		6.2.1 Dehydration of Grouting Entering the Masonry
		6.2.2 Measures Against the Dehydration
	6.3 Grout Strength Versus Masonry Strength Required
		6.3.1 Introduction
		6.3.2 Estimation of the Strength of Existing Stone-Masonry Before and After Grouting
	6.4 Expected Strengths of Grouts
		6.4.1 Introduction
		6.4.2 The Main Parameters Influencing the Strength of the Grout
		6.4.3 Experimental Checking
		6.4.4 Indicative Strength Values of Grouts
	6.5 Grout-to-Stone Bond Properties
	6.6 Selection of a Required fgr,c-range, for Targeted fwc-values
	6.7 Shrinkage
	Appendix: Data Regarding Grouts Compressive and Tensile Strength in Function of the Water to Solids Ratio
	References
7 Durability
	7.1 Introduction
	7.2 Physical Effects
		7.2.1 Water Introduced During Grouting
		7.2.2 Fluctuation of Moisture
	7.3 Chemical Effects
		7.3.1 Sulphate Reactions
		7.3.2 Alkali-Silica Reaction (ASR)
		7.3.3 Chlorides
		7.3.4 Leaching
	7.4 Brief Presentation of Main Literature Results on  Grout’s Durability Testing
	7.5 Guidance for the Grout Design Versus Durability
	References
8 Optimisation of Grout Performances
	8.1 Introduction
	8.2 The Interaction Between Design-Parameters
	8.3 Increase of Fines to Improve Compatibility Between Stability and Fluidity
	8.4 Increase of Fines to Improve Stability Itself
	8.5 Modifications to Obtain a Minimum Tensile Strength
	8.6 Addition of Superplasticizer
	8.7 Conclusion
	References
9 Practical Guidelines for the Mix Design of Grouts in Masonry Strengthening
	9.1 Selection of Binders
	9.2 Selection of a Wnom-value
	9.3 Checking the “Fineness” of the Binders’ Mixture
	9.4 Additional Ultrafine Materials
	9.5 Expected Fluidity Factor and Minimum Water-to-Solids Ratio
	9.6 Maximum Water-to-Solids Ratio to Ensure Stability
	9.7 Experimental Examination of the Candidate Composition
	9.8 Early Critical Bleeding
	9.9 Strength Evaluation
	9.10 Possible Simplification
	9.11 Worksite Conditions
	References
10 Practical Recommendations for the Execution of Grouting
	10.1 Introduction
	10.2 Preparation of Masonry and Installation of Injection Tubes
		10.2.1 Masonry Survey
		10.2.2 Cleaning of Loose Material and Sealing of Cracks and Voids
		10.2.3 Drilling the Holes—Grid of Injection Tubes
		10.2.4 Cleaning of Drilled Holes
		10.2.5 Installation of Injection Tubes
		10.2.6 Installation of Fine Injection Tubes in Specific Cases
	10.3 Main Characteristics of In Situ Grouting Equipment
		10.3.1 Mixer
		10.3.2 Agitator
		10.3.3 Grouting Pump
		10.3.4 Grout Pipe Lines
		10.3.5 Grout Recorder
	10.4 Preparation of Grout and Execution of Injections
		10.4.1 Mixing Procedure
		10.4.2 Injection Procedure
		10.4.3 Finishing of the Masonry Injected Face
	10.5 On-Worksite Checking of the Prescribed Grout Design Data
		10.5.1 Pilot Production of Grout in the Worksite
		10.5.2 Pilot Masonry Application of Grouting
	10.6 Quality Control of the Grout and of the Injection Procedure During the Execution of Works
		10.6.1 Visual Inspection
		10.6.2 Checking Grout Characteristics
	10.7 Final Report of the Execution of Injections
	10.8 Assessment of the Grouting Effectiveness After the Completion of the Works
		10.8.1 Core Taking
		10.8.2 Endoscopy
		10.8.3 Sonic/Ultrasonic Methods
		10.8.4 Radar Technique
		10.8.5 Other Non-destructive Methods
		10.8.6 Structural Dynamic Measurements
	References