Gibside SEN School, Gateshead

Aarsleff Ground Engineering carried out drilling and grouting
operations for the construction of a state-of-the-art special
needs primary school in Saltwell. Located on the Shipcote Playing
Field on Avenue Road, the new single-storey school building will
cater for 170 key stage 1 and 2 pupils aged from 3 to 11 years.
The school will feature secure external play facilities, a sensory
courtyard, a hydrotherapy treatment pool and a multi-use games
area.

On behalf of Wates Construction and Gateshead Council, Aarsleff
were awarded the scheme in mid-October 2019, commencing on
site on the 28th October and demobilising on the 17th December
2019.

Holes for drilling and grouting were spaced on a 4.25m staggered
square grid, of which Aarsleff drilled 364 No. holes and mixed
and injected 900 Tonnes of grout. 5% of the total number of holes
drilled on the site were pressure tested and 4No. grout cubes
were taken per day to ensure compliance. The required grout
strength was in the order of 0.7 – 1N/mm2

Aarsleff deployed its Klemm 806, Boart drilling rig and bespoke
grout batching equipment for the works, which were completed
in December.

In the planning phase of the development, a desk study and
subsequent site investigation were carried out which indicated
the site was located on an overburden of soft clay between
depths of 1.9m and 4.0m. Following the clay, there were
consistent interbedded layers of Sandstone/Mudstone with
rockhead ranging between 12.0m and 18.3m. Boreholes indicated
that the majority of the site was Broken Ground/Soft with some
boreholes still showing solid coal; the average thickness of the
worked seam showed to be 2.6m at a depth of roughly 18m.

Aarsleff’s Graduate Civil Engineer Liam Trick said:

“It was a challenging project due to the adverse weather
conditions having an impact on our production and deliveries.
The heavy rainfall caused a lot of standing water which in effect
caused parts of the site to be deemed completely inaccessible.
We utilised our own excavator in order to reduce the impact
the telehandler would have had at leaving large ruts around the
site. Under the conditions we were tasked with, the team on
site performed excellently without any problems. Wates held a
daily co-ordination meeting with all contractors involved to plan
a sequence of works for the next day to ensure that safety and
production was maximised. We used a silo allowing us to use
blown cement instead of bagged cement which in turn reduced
the cement dust produced and also increased the production
rate. This method was very effective and will be used in future
projects where applicable. Wates also commented on how the
site lads worked very well under the conditions they were faced
with which is always nice to hear.”

It is hoped that the school will be ready to welcome pupils and
staff in early 2021.