3D Modular Precast & Prefinished Toilet/Kitchen

Saurabh Purandare, Director, & Khaja Rasool, Structural Engineer, Innovela Building Solutions, Pune, discuss an out-of-the-box construction approach for meeting today’s call for shorter timelines and reduced cost in construction, while ensuring the highest standards and uniformity in quality in projects.

3D Maodular Precast & Prefinished Toilet/KitchenFigure 1: Precast 3D Element process

Rapid urbanization and the surging construction activities, along with diminishing labour has pushed leading players to adopt mechanized and precast methods of construction.

The 3D modular standardized precast (onsite / offsite) pre-finished elements, specifically in the toilet and/or kitchen areas is an alternative that promises transformative improvements in time, cost, quality, health and safety. It involves the production of 3D precast and prefinished modular toilet/kitchen units in controlled factory conditions, prior to their transportation to site.

It eliminates the problems inherent in 2D large panel-based construction by minimizing the number of joints and connections, which are the root cause of leakages, seepages, and lack of ductility in the conventional precast construction.

Government of India has already directed the use of 3D Technology to speed up housing construction with huge demand for houses, possibly with lowest price, and in the least possible time. For high-rise construction, lateral load resisting is a requisite, therefore india is adopting a shear wall system and moving away from conventional column, beam and slab based construction since the past decade.

Precast Technology: Current Scenario in India
Precast Technology is being used in India majorly by private players since the last 10 years or so by setting up their own 2D Precast Panel Production facilities at developed cities in India. Most of the production facilities are configured to produce large panels, hollow-core slabs, and solid slabs. During this period, approximately 100 million sqft of precast concrete construction was carried out, which is not even 2% of the total size of the construction industry.

3D Maodular Precast & Prefinished Toilet/KitchenFigure 2

Even though Precast Concrete Technology offers some distinct advantages like time saving and better quality of construction, it is not popular, despite its potential, in India (so far). Now a day’s precast readymade elements are widely adopted for the hybrid system of construction (combination of cast in situ load bearing vertical elements and precast slab elements). So far, 70% of overall Precast Buildings constructed in India belong to EWS, LIG and Slum Rehabilitation Housing projects funded by respective state governments, but there is also need for adoption of Precast Technology in large-scale private projects as well.

3D Maodular Precast & Prefinished Toilet/KitchenFigure 3: 3D Moulds

Shortcomings of 2D precast technology
The reasons for 2D conventional precast construction being not so popular in India are:
High Indirect cost: The initial capital investment and plant maintenance are high for setting up a precast plant near or at site. This method of construction requires big players, large-scale projects, or speed of construction from 1 million sq.ft built up area per annum to a maximum of 3.5 million sq.ft built up area per annum.

Expensive Connections: Higher cost of joints & connections and of hardware items like grout, sealants, connecting loops, temporary props, scaffolding etc.

Higher Crane cost: 2D Precast Construction involves about 15-20 number of elements per apartment which require more cranes for erection, for which the expense is high.

Non-Standard Architectural Plans: There is lack of understanding and exposure for most architects regarding Precast Technology. There is also lack of standardisation in the plans which indirectly impacts the technology. This leads to negative and a mixed perception by the stakeholders in the construction industry, so there is resistance to adoption of the technology.

Laborious & Time-Consuming Finishing Work: Even though the completion time of a structure’s completion is vastly improved, the saving of time for the overall project is not so significant as the finishing work still involves a lot of trades and labour.

3D Maodular Precast & Prefinished Toilet/KitchenFigure 4a: Production process of the 3D Elements

Advantages of Out-of-Box Construction Approach
An Out of Box construction approach is a revolutionary method in building construction; it involves use of 3D Modular precast, prefinished Toilets and/or Kitchen units (Pods) produced offsite in a controlled environment. These Pods can be easily standardised accross different apartment sizes and projects. The architectural plan and structural frame is made considering these 3D Pod Modules as primary vertical and lateral load- resisting systems and other rooms such as the living room, bedroom etc are configured around this basic core.

Lower Indirect cost: Due to standardisation of kitchen and toilet units (wet areas), standardised modules are formed in moulds etc. which can be used in multiple projects with a lot of repetition in the moulds.

Scalability: The Out of Box construction approach does not necessarily need high project volume. This system is highly scalable where speed of construction can be as low as 300 apartments per annum to a maximum of 25000 apartments per annum.

Cost Optimization: This is achieved due to the minimum number of joints/connections, up to 50% reduction in crane cost due to less number of elements per apartment, reduction in transportation cost due to optimum use of trailer capacity, reduced temporary supports/props, cost-effective solutions for reduced handling of elements, reduced manpower due to increased automation, and optimum infrastructure requirement.

Improved structural Performance of Building: Use of Monolithic 3D Units improves the structural behaviour due to box action and offers better ductility.

Pre-Finishing of 3D Pods: The 3D Toilet/Kitchen pods can be delivered with all internal finishes like tiling, partition walls, dado, etc. and with all internal cosmetic fittings, which ultimately saves in lead and lift of finishing material and labour.

Leak-proof wet areas: Water leakage risk is eliminated due to monolithic casting of slab and walls in the kitchen and toilet areas. Sunk requirements etc. are possible with this system.

3D Maodular Precast & Prefinished Toilet/KitchenFigure 4b: Production Process

Structural Design, Production, Logistics and Erection
At the preliminary design stage, structural framing has modularisation of the toilet/kitchen units by configuration, sizes, dimensions and weight of units finished and un-finished, and transportation and erection considerations. Structural integrity of 3D elements with remaining structure is detailed properly to establish a high degree of ductility and emulative design.

Especially horizontal joints (wall to wall joints) between 3D units are designed to transmit the axial, moment and shear forces due to gravity and lateral loads. These are designed for eccentricity as per the building code requirements. Horizontal joints with wall connections are designed to avoid complications during erection and to achieve speed of construction. Horizontal joints between 3D units and structure must ensure the floor diaphragm action. The 3D units and layout is laterally connected and designed such that horizontal forces can effectively be transferred to the buildings laterally load resisting system.

Although 3D Pods are monolithic, the connections with other elements are detailed with peripheral and internal ties as per the robustness and codal provisions.

3D Maodular Precast & Prefinished Toilet/KitchenFigure 5: Transportation and Stacking of 3D Pod Elements

Production of 3D Precast Elements
Production of 3D precast elements can be done through special 3D Moulds. These elements are cast with slab and walls without conical shape by using hydraulic collapsible inner mould. Moulds are fabricated in steel with comprehensive design to withstand the handling and production process for the lifetime required.

3D Moulds are equipped with concrete vibrators and heating system to accelerate the curing of the concrete or by steam curing as per the requirement. Concrete is self-compacting concrete. Complete reinforcement cage of the Pod is placed into the base mould; MEP and cast in accessories are placed and concreting is done after quality inspection. The production process depends on the Pod with top or bottom slab. Pod with top slab can be cast in one pour and Pod with bottom slab can be done in stages, as required. After initial strength, the Pod is dispatched to the finishing yard.

Production of 3D Pods should satisfy the production tolerances in terms of length, cross sectional dimensions, squareness, straightness, twist, flatness and diagonal measurements as per the codal provisions.

3D Maodular Precast & Prefinished Toilet/KitchenFigure 6: Erection of 3D Pod Elements

Logistics
3D Pods can be handled using special lifting frames designed to lift the elements. Precast Pods with bottom slab can be handled with stationary base throughout the process of multiple stations in the production facility. Typically, precast concrete elements are de-moulded and lifted from their casting position to the storage yard and delivered to site, once they reach the required strength. If the elements have not gained their full design strength, they would be more susceptible to damages during handling. Two 3D Pods can be stacked one above the other to reduce the storage area. Transportation of 3D elements of quantity 1 or 2 can be decided based on the weight of the elements and can be fully utilised for the trailer capacity.

3D Maodular Precast & Prefinished Toilet/Kitchen

Erection
Precast 3D Pods must be installed with special attention to their alignment during erection. Proper access with platform has to be provided with all safety measures. Connection of elements using mechanical splice, preferably grouted couplers, eases the erection. Grouted splice connections help to align the 3D Pod in the least possible time since the projection length of the bar is less. Most of the erection instruments can be eliminated like push pull props, propping anchors etc. Steel frame is only used to handle and erect 3D Pods, and there must be proper planning of the order and progress of modular erection sequence from the production to supply to site. Erection tolerances have to be followed as specified in the code.

3D Maodular Precast & Prefinished Toilet/KitchenFigure 9: Typical floor plan and Unit plan (LHP Ranchi)

Out-of-Box Construction by Innovela
Innovela has been part of many medium- and large-scale projects by offering structural design services. Ongoing projects include the Suraksha city and the Light House GHTC project in Ranchi.

3D Maodular Precast & Prefinished Toilet/KitchenFigure 10: Typical 3D Pod Element for Kitchen and Toilet (LHP Ranchi)

Conclusion
The fast-growing construction industry of India is mired in problems such as shortage of skilled workers, reduced productivity, and uncertainties in delivery cycle. It is also stuck with 2D construction, assembling numerous elements, and sealing multiple joints, which pose many challenges during construction. Now, several 3D pilot projects are underway, many mock-ups have been done, and private players are also slowly adopting the technology.
Concrete Construction April - May 2022
3DXB Group Sets Guinness World Record for Largest 3D-Printed Villa in Dubai

3DXB Group Sets Guinness World Record for Largest 3D-Printed Villa in Dubai

3DXB Group, a leading innovator in 3D printing solutions for the construction industry, unveiled its achievement in making the world’s largest 3D-printed villa in Dubai. This groundbreaking project signifies a pivotal moment in the UAE

Read more ...

Rapidcast Boundary Walls: Best Quality Concrete Precast Textured Walls

Rapidcast Boundary Walls: Best Quality Concrete Precast Textured Walls

Rapidcast LLP brings to you for the first time in India the best quality concrete precast elements such as RCC precast compound walls and RRC precast stormwater UDrains. The new generation Rapidcast boundary wall/fence is a high quality precast

Read more ...

Elematic's Large Precast Concrete Plant for My Home GRAVA Project

Elematic's Large Precast Concrete Plant for My Home GRAVA Project

Hyderabad is witnessing the construction of Asia's tallest towers with a planned built-up area totalling 3.7 million sqm. The two 180-meter towers, each comprising 43 storeys, will be accompanied by six more similar towers. With each tower

Read more ...

Benefits of Shear Keyed Surfaces in Precast Building

Benefits of Shear Keyed Surfaces in Precast Building

Depending on the finish of the concrete surface, different coefficients are assigned by international codes in the calculation of shear resistance. The American Concrete Institute Code ACI318, Nov.19, states the following: Chapter 16.2.1.1 – Transfer of forces by

Read more ...

Revolutionizing Precast Industry with Advanced Tracking of Precast Concrete Elements

Revolutionizing Precast Industry with Advanced Tracking of Precast Concrete Elements

The precast concrete industry is undergoing a transformative change with innovative software solutions that offer enhanced tracking of precast concrete elements. One of these pioneering software solutions is StruSoft’s Impact Precast, which aims

Read more ...

Emerging Trends & Growth of the Prefab Industry

Emerging Trends & Growth of the Prefab Industry

Prefabricated technologies are becoming increasingly popular in the construction industry, particularly for large-scale construction. As prefabricated structures continue to evolve and improve, they are being used to construct warehouses, factories

Read more ...

Precast RCC Structures versus Pre-Engineered Steel Structures

Precast RCC Structures versus Pre-Engineered Steel Structures

A comparative study on Industrial Building Adopting Structural Frames as Precast RCC and Structural Steel Frames with Prestressed Precast Hollow Core Slabs as Flooring Slabs, presented by C. A. Prasad, Director, METEY Engineering Consultancy, Hyderabad

Read more ...

My Home Mega Project Shows Potential of Precast Construction Technology in India

My Home Mega Project Shows Potential of Precast Construction Technology in India

Storey by storey, Asia’s tallest precast towers with a total planned built-up area of 3.7 million sqm are rising towards the sky in Hyderabad. These two 180-meter towers of 43-stories each will be followed by six more similar towers. With each tower

Read more ...

Mekuba: A Leader in Mould Releasing Agents for Concrete

Mekuba: A Leader in Mould Releasing Agents for Concrete

With over 47 years of experience in the petrochemicals industry, and an expert in the formulation and production of mould-releasing agents, Mekuba Petro Products is growing rapidly in the construction chemicals segment with a daily production

Read more ...

Dextra Groutec Coupler - A Unique Solution for Reliable Joints in Precast

Dextra Groutec Coupler - A Unique Solution for Reliable Joints in Precast

Dextra has added yet another customer-centric, innovative, and custom engineered product - the Groutec Coupler - an efficient product that has been qualified and tested successfully on several major infrastructure projects in the recent past. With the

Read more ...

India an Important Market for TOPWERK

India an Important Market for TOPWERK

Sachin Shetty, India Head – Operation & Sales, and Rajesh Jha, India Head - Sales & Market Development, TOPWERK INDIA, discuss the potential of precast concrete construction in India, localization of non-critical components to bring down cost, and the possibilities of digitalization

Read more ...

Vollert: Building A Stronger India with Precast

Vollert: Building A Stronger India with Precast

Vollert India has recently expanded its production capacity in Sikandrabad (UP) India. As a global leader in precast concrete components, systems, and machine solutions, Vollert’s investment in India indicates a growing interest among German companies

Read more ...

Precast India Connector - Helping Precasters Overcome Cost & Time Overruns

Precast India Connector - Helping Precasters Overcome Cost & Time Overruns

Precast India Connections, a new entity of Precast India Infrastructures, has innovated and patented a method of achieving a Dowel-Sleeve connection that functions even in the horizontal direction. Kapilesh Bhate, MD, Precast India Connections, shares

Read more ...

Prensoland Modern Precast Floors Appearance of the iHCS

Prensoland Modern Precast Floors Appearance of the iHCS

Pre-stressed concrete hollow core slabs used for building floors are unidirectional members; they are laid one next to the other until the complete carpet area is covered. In the presence of lateral loads like wind, or due to seismic episodes, they behave

Read more ...

Vollert India Expands Production Capacity

Vollert India Expands Production Capacity

The expansion of the Vollert plant in India marks an important milestone in the company’s commitment to provide high-quality products to customers. With the increased production capacity, the company aims to expand its market share and strengthen

Read more ...

Brimax AAC: An Indian Lighthouse Project from HESS AAC SYSTEMS, Netherlands

Brimax AAC: An Indian Lighthouse Project from HESS AAC SYSTEMS, Netherlands

Brimax AAC Products LLP contracted Hess AAC Systems to supply a new AAC plant in Vadodara, India, with a capacity of 680 cbm/day (expandable up to 900 cbm/day with reinforcement for panel production). This order strengthens Hess´ position as

Read more ...

Vollert India Expands Production Capacity to Cater to Infra Development Sector

Vollert India Expands Production Capacity to Cater to Infra Development Sector

Vollert India, based in Sikandrabad, near Greater Noida (UP) since 2017, is strengthening its commitment to India; it is now expanding its production capacity of precast machinery and components to meet the greater demand from India’s fast

Read more ...

Elematic Precast Technology Solutions for Building, Industrial and Infra segments

Elematic Precast Technology Solutions for Building, Industrial and Infra segments

Elematic offers a comprehensive range of precast technology solutions for the Building, Industrial and Infra segments. Elematic precast technology enables clients to automate the production of walls, slabs, columns, beams, and stairs, providing an efficient

Read more ...

Advanced Concrete Curing Systems from Kraft Curing

Advanced Concrete Curing Systems from Kraft Curing

Kraft Curing Systems GmbH is offering advanced concrete curing systems that optimize the hardening process of concrete. Kraft Curing’s Advanced Concrete Curing System provides numerous solutions, from vapor-based (steam) systems mainly for the precast

Read more ...

Why Automating Production is the Solution

Why Automating Production is the Solution

Automating the production processes will lead to reduced wastage, fewer errors, more precision, greater safety, and higher quality of the end-products, and in a shorter period of time. First, we need to understand where we stand today as regards industrialisation

Read more ...

To get latest updates on whatsapp, Save +91 93545 87773 and send us a 'Saved' message
Click Here to Subscribe to Our eNewsletter.