Case Study

Construction | Excavation

The One

Problem

The new skyscraper, exceeding 1,000 feet in height, will soon mark Toronto’s skyline as the tallest high-rise building in Canada. Whenever a structure of this height is built, significant excavation is performed at the build site to provide a deep, solid foundation to secure the structure. However, in urban, densely constructed areas, excavation of this nature can create a number of safety issues.

For one, when excavating in a dense urban environment with a lot of existing utilities, infrastructure, and closely adjacent structures, there is a potential for unintentional damage. Additionally, during the excavation process, equipment and workers are often subjected to safety risks related to stability of the temporarily installed shoring system. Fortunately, there are many sensors that can be installed in and around the construction site to monitor the impacts of the excavation on adjacent structures, as well as the stability and integrity of the shoring system. This is often accomplished using a combination of vibration, spatial, and strain sensors. When groundwater is near-surface, there will also be dewatering programs put in place, which can be easily incorporated into the automated monitoring program.

Proactive risk management has been proven to be very cost-effective when using modern instrumentation and automation techniques, and is further enhanced with the ease of use of sensemetrics’ cloud-connected workflows.

 

Solution

In May of 2018, Monir Precision Monitoring installed a sensemetrics cloud-connect device to automate Measurand’s ShapeArray (SAAV), an in-ground flexure sensing device for automated detection and measurement of ground movement. These measurements are critical to safe operations on the project during the foundation construction, as well as protection of neighboring buildings and infrastructure.

Whereas historically, this information would be manually collected using inclinometers operated by field crews, the new automated solution provides a near real-time data stream to a secure cloud platform which can be accessed by the entire project design and construction team. Cloud connectivty and processing provides immediate computation, analytics, alerting, and automated report distribution. sensemetrics was chosen as the platform for construction data monitoring because of its plug & play support for Measurand’s ShapeArray sensor, and the platform’s unique capability of providing streaming monitoring data to any location via a mobile device.

Results

An automated ground displacement monitoring solution consisting of products from sensemetrics and Measurand has an 87% higher chance of detecting a critical displacement within 24 hours than a traditional manual measurement method performed weekly. A cost comparison between manual and automated monitoring in this application shows a savings of over 60%, despite offering a clear advantage in early detection and warning.

Project Details

Location: Toronto, Canada

Date: 2018-2019

Owner: Mizrahi Developments

Instrumentation: Monir Precision Monitoring, Inc.

Project Type: High Rise Construction, Shoring Excavation