Construction projects execution has changed drastically more from last decades. In execution of project there are many departments working for successful project execution. These all departments need to cope up with the changes occurring in industry. One of the departments helping for execution of project is store. To execute project successfully store department role is very important. In traditional system, store is only considered as the storage place. Small or medium scale construction organization does not use the store as effective department for in time project delivery. Store management can support to Just in time concept and helpful for inventory control and in time project completion. Store management increases the efficiency of work and helps for smooth working. It is observed that the activity going on site are delayed majorly due to unavailability of material. Poor store management leads to purchase of material with high rate as emergency from local vendors to avoid delay. Sometimes the material within the stor due to poor store management gets wasted and to lead cost for project. This paper is to study effective store management which helps to JIT approach causing minimum inventory cost and wastage of material.
I. BACKGROUND OF STUDY
In construction industry, changes are occurring rapidly and with these changes new ideas needs to explore. These Ideas may useful to minimize cost, speedy & smooth work. When these ideas are implemented systematically it ultimately reduces the work load stress, and helps to improve the working condition. The store management is one of the supporting department for execution and management. It can improve the JIT implementation on project. Factors affecting for implemented techniques are rarely discussed. For material to reach in time store plays important role.
Just in time is method used in production industry which improves the efficiency of manufacturing. JIT provides information what is required, when it is required and in how much quantity it is required. By applying the JIT we can minimize the inventory cost. But for proper implementation of JIT store management plays important role. The information required for JIT is provided by store management. Well managed store can efficiently help for measuring stock, issuing material and providing data to purchasing team to place order at right time. Poor store management can impact JIT and indirectly the project.
III. PROBLEM STATEMENT
Material management system on major construction projects have been changing from decades. New techniques being used for improvement of material management. JIT is one of the techniques used for material management but there are some challenges in implementation of JIT effectively.
JIT totally depends on the site store. Therefore, this study on store management is carried out to study the process of store for effective working of JIT o construction project.
IV. SITE STORE
Site store is temporary store, which is used for storage of purchased, transferred materials. It plays important role in communication within the site execution team and top management like managers, VP, MD of organization. Site store maintain the record of Purchased material, Material consumed on site and material transferred from site or transferred to other site or rejected material.
Site store is first check-up gate which checks the material for its quantity, make, size, dimensions and then send it to quality department before unloading for checking. After unloading of material, it is store responsibility to stack and keep it properly. Care should be taken it should be in good condition till its usage.
For better JIT implementation store management needs to be in a systematic way. For proper store management steps to be follows as below.
A. Resource Coding
We use multiple Resources on construction project. Bifurcation with coding to the each and every material can make the task easy for finding the material. Resource coding should be done at the time of estimation. So that in each phase the tracking of resources will be easy. Bifurcation and coding to the resources makes the easy understanding to the Account department also.
One of the way to bifurcate the material is bifurcating them with its usage. Material which can be used for civil activity should be under civil material head, material used for electrical work should be under electrical head, material used ofr safety work should be under the safety material head ,asset material under the asset head and like wise for other.
B. Store Arrangement
Store should be well arranged so that each and every material stored in store has its defined place. One can easily find or store material in store. 5s technique should be implemented for arranging the store. Display the name plates for racks with the codes and material name. Arranging the material helps to issue the material easily.
There should be working area in middle of store. These area can be used for received material counting, material Cleaning , material maintenance purpose.
C. Material Issue
Actual role of store starts from here to improve the JIT implementation. Before issuing the material from store issue slip should be generated at site level. And data should be maintained till end of the project. Issue slip data gives us information about quantity usage for particular activity in that period. It also provides the base data for minimum stock. By the time of entering issue slip and issuing the material we comes to know the stock of material.
D. Periodic Stock Checking
For inventory control we should have a data about the stock of material in store. Store arrangement helps us for easy stock checking. The theoretical stock can be derived form issue slips. If we combined all issued slip together we can calculate theoretical consumption of material.it can be derived as,
We should always cross check the theoretical stock with actual stock we have in our store. Actual stock should be checked periodically and reconciliation for materials should be done to know the stock. Stock on store should always be equals to theoretical consumption.
Actual Stock = Theoretical consumption.
E. Minimum Stock
For the better implementation of JIT there should be a time to complete the process of purchase. Process starts from indent to material receival requires time. To cope with this we should have a minimum stock in our store so that there will not be any impact on activity due to material unavailability. Minimum stock can be calculated form past experience or from using constants. For calculating the minimum stock we can use following steps.
Derive the Constants
By the of estimation team derive the constants.for RCC work we have X cum concrete, Y sqm shuttering and Z MT steel frequired for execution the A sqft area. We can calculate the constant as,
Steel Constant P = Z x 1000 Kg of steel for executing the A soft area.
i.e P= Z x 1000 / A Kg / sqft
Shuttering constant Q = Y x 10..764 sqft of shuttering for executing the A sqft area
i.e. Q = Y x 10.764 / A sqft/ sqft
Concrete constant R= X x 35.33 cuft concrete for executing the A sqft area
i.e. R= X x 35.33 / A Cuft/sqft
From constants we comes to know the quantity of activity for executing the area.go through the planning cycle and calculate the periodically area execution and we can easily maintain the minimum stock of material like steel, cement, row material, shuttering material etc.
2. Consumables Stock
For activity completion consumables material stock is required. In analysis these items comes under B or C categories. For minimum stock calculation of these material we can use thumb rule.for example,
To complete the steel activity we required Cover block and binding wire. These can be calculated as,
According to past experience minimum 160 to 200 nos of cover block are required per MT usage of steel.
So, for executing Z MT steel qty we should have cover block in our stock Z x 200 nos.
Minimum stock of cover block = Z x 200 nos .
For binding wire we use a constant of 13 to 15 kg per MT execution of steel.i.e to execute the Z mt steel qty we required Z x 14 kg of binding wire.
Minimum stock for binding wire = Z x 14 kg
For all materials we should calculate the minimum stock to avoid emergency. This can avoid the time delay due to material unavailability.
Display the board of minimum stock of material to be maintained in store with project managers approval.
This is to conclude that, for the material to be reach in time on site, store management gives the support in advance. Procurement of material within the time can done with the help of inventory management. Therefore it will leads to JIT Implementation on construction site efficiently.
 Maryam al-zweeni & Abbas Nawar Al-Musawi,Just in Time Production, Wasit University,1441 AH
 Tongguang si,Hong Xian Li,M Reza Hosseini, Chunlu Liu, A solution to Just-in-Time Delivery for Off Site Construction :-A conceptual Model. Jinan, ChainaConstruction Research Congress, 2020.
 Patil Yogendra, Patil Dhanajay, C. Zhu, J. K. O. Sin, and P. K. T. Mok, “Feasibility study of just in time inventoery management on construction project,” IRJET,Vol. 02,issue 04