Excavation of underground spaces in hard rock is often conducted in large scale infrastructure projects which often encounters significant challenges with water ingress. By having too much water ingress to the underground space can result in significant delays in the construction process, compromise the workability during excavation and influence the surrounding groundwater level. To effectively manage the water ingress is critical for the excavation process and sustainability of local environment. By geologically investigating the rock mass, the geological and hydrogeological conditions are determined which forms the basis for a successful grout design. With known conditions, the grouts properties are determined to cope needed penetration and acting forces. To accurately measure rheological properties of grout, a rheometer is used to measure grouts properties during the first five hours of curing.

To rheologically characterize grout, lab experiments are conducted with different measurement geometries with both oscillatory tests and rotatory tests. To follow the curing process during the first five hours, there exists no clear best setup. But rather each me measurement geometry has its own benefits and downsides. This thesis concludes that the cone and plate geometry is the most appropriate measurement geometry if the focus is early on, in the curing process. If the aim is to follow the curing process for multiple hours, the plate and plate geometry is more suitable. 

The two predominant mechanical events during grouting this thesis analysis are the stress from hydraulic gradient and the shear strain induced by blasting the rock mass. To study the effects from the hydraulic stress, theories on viscous fingering is implemented and a mathematical equation is derived which predicts when viscous fingering occurs. To investigate this theory, tests are conducted in a fracture replica in conjunction with rheological measurements. The results validates the theory which suggests the flow, viscosity and hydraulic gradient determines when viscous fingering occurs. 

In addition to the lab tests, two field tests are conducted to investigate the blasts influence on grout. During these field tests, the transmissivity is measured by water loss measurements. The rock mass is then grouted followed by another water loss measurement. The rock mass is the charged and blasted within three hours of curing. By having triaxial vibration measurement devices installed in the surrounding rock mass, vibrations are measured and is then used to calculate the shear strain in the rock mass. By implementing the rheological measurements from the lab environment, it is determined how the grout behaves during blasting. This study concludes that grout will only experience high enough shear strain very close to the initiation point of the explosives. The shear strain from the blast will not permanently damage the grout but temporarily. During this time, the grout is more prone to erosion. This time of reduced strength can be determined by modifying a 3iTT test commonly used in food science.