VERTICAL SPACER SHIM BETWEEN FORMWORK AND IRON COLUMNS

01 December 2013

TOTAL was presented Construction Work Award category Applicable Technology during Indonesian COnstruction 2013. Innovated by Ackmad Syaifudin, Senior Site Manager of PT Total Bangun Persada Tbk.

Issues are commonly found in construction. Issues can either be challenges or obstacles depending on the view of the constructors. PT. Total Bangun Persada chooses to develop an innovation in overcoming the issue. The innovation is a vertical steel spacer shim between formwork and steel columns which is the brilliant idea of Achmad Syaifudin, Senior Site Manager of PT. Total Bangun Persada, Tbk.

“This Spacer Shim is made by utilizing leftover materials on the project which is expected to facilitate during execution in the field,  time and cost efficiency..” – Achmad Syaifudin

Innovation is a new invention or development of existing matter. Usually, innovation is developed for several purposes, such as improving quality, reducing cost of work force, raw materials, environmental destruction, energy consumption, replacing product or service, as well as broadening the reach of product or service. Usually, the emergence of innovation is the result of an existing problem which must be solved with new thinking.

This problem becomes the background for PT. Total Bangun Persada to develop the innovation of steel spacer shim between formwork and iron columns. As a construction company which handles high-rise building projects, PT. Total Bangun Persada often finds obstacles in the construction process of projects. Thus, the innovation of vertical steel spacer shim was developed to replace the vertical wooden spacer shim to obtain cost efficiency and effectiveness, quality assurance, as well as to accelerate time of construction.

In construction project, there are five crucial aspects which must be considered, namely cost, quality, time, work safety (K3), and environmental aspect. Those aspects must be managed properly and accurately to obtain specific goals because of limited resources. Thus, PT. Total Bangun Persada developed the vertical spacer shim innovation using the BRAIN concept, which are Benefit, Repetition, Application, and Innovation. Benefit is the advantage gained as the impact of innovation on five existing aspects (cost, quality, time, safety, and environment). Innovation must also be used by other work units (type of project) so that a consideration must be made on whether to modify or not. In other word, the innovation can be utilized repeatedly.

Whilst, Application is the practical level of the innovation in its implementation so that it is known whether additional resources are needed or not. The final aspect of BRAIN, innovation, is related to how advance the innovation/development was. The innovation level encompass new findings, improvement, repetition, or just another method.

Steel Vertical Spacer Shim

This vertical spacer shim is a new idea/notion which is created during implementation in the field. Vertical spacer shim is a result of the project team’s creativity to facilitate work implementation. The vertical spacer shim has been applied by PT. Total Bangun Persada on Greenbay Pluit Project. On a project with a contract value of approximately Rp210.486.969.989,-, PT. Total Bangun Persada as contractor must complete the work on 4 Anami Towers Phase 1A and 4 Anami Towers Phase 1B and External Phase 1.

Vertical spacer shim is utilized in construction between the iron columns and the formworks. On the old method, the vertical spacer shim which is used is made of wood. These wooden vertical spacer shims are not reusable thus creating considerable waste. In addition, installation of the wooden vertical spacer shim is difficult and not precise. The installation takes a long time and requires more work force.

The wooden vertical spacer shims which have been installed require several verticality check to ensure the vertical spacer shims are installed properly. Not only does the installation of the vertical spacer shim require a long time, but the preparation of the casting also takes a long time. Other important matters of note concerning wooden vertical spacer shim is the unsafe work condition resulting in a considerable risk to the safety of the workers.

Viewed from the aspect of work result, wooden vertical spacer shim creates areas that are cluttered and unkempt. Wood can only be used once creating considerable waste and wasteful utilization of wood. Elevation accuracy of the casting result is not very good as well as the possibility of shifting or tilting of the casting result. The resulting thickness of the concrete cover is also inconsistent. Because of the difficult installation, fatigue level increases resulting in increasing risk of worker’s safety.

The inadequacy of wooden vertical spacer shim becomes a significant issue in the implementation of construction work by PT. Total Bangun Persada. Thus, PT. Total developed the vertical spacer shim made of steel. Unlike its wooden counterpart which is vertically installed on six sides of the column, a steel angle shim only has to be installed on two corners of the column.

Other quality of this steel angle shim is the simple, safe, fast, and accurate installation procedure. The steel casting preparation can also be done faster, in addition to fewer workers required to install the steel angle shim. Moreover, the steel angle shim has an innovative casting elevation adjuster; enabling a simpler and more practical elevation adjustment.

Seen from the work output, the steel angle shim creates a cleaner and tidier work environment. It produces consistent site of concrete cover and accurate level of steel casting elevation. The use of steel does not include wood elements and is reusable, thus free from generating waste. Works using steel angle shim has a good verticality resulting from proper casting while reducing hazardous risks for worker’s safety and security.

There is a significant difference between the use of wood and steel angle shim in a comparative analysis. In the analysis of usage per column, it requires 6 wooden shims per column with a cost of Rp32,000/4 M1. While wooden shim method only requires 2 sets of shims, each of which is Rp100,000.

Nevertheless, despite a more expensive cost of steel angle shim, it does not produce waste. While for wooden shim, the waste factor reaches 30%. From the calculation of shim spacer cost per column with waste expenses at the end of the project, the wooden shim method requires greater cost.