Professor S. V. Deodhar, Ex Director SSVPS College of Engineering Dhulia (Maharashtra), Professor of Civil Engineering Rishiraj Institute of Technology Indore (M.P.)

Studies on hidden beams have been carried by various researchers. Its use for high rise buildings with raft foundation is of very useful. However, its use for low rise buildings may not be effective to a considerable extent. In this paper, methods have been suggested to improve lateral load resisting capacity of low rise buildings during earthquakes.

Introduction
Earthquake causes strong random ground movement and ground shaking. These ground accelerations cause building to vibrate and thus induce inertia forces in them. Earth movement causes horizontal forces on foundation causing foundations to move along with soil. These cause deferential settlement causing building structures to develop severe cracks and consequently collapsing. In case of low rise structures of height about 12 to 14 meter having 4 to 6 floors including soft story, isolated footings are provided as foundation. These structures have less resistant to earthquake forces as having a soft story, mostly fails to resist earthquake forces. These five to six floors consists of ground floor as parking floor, called as soft story and three to four floors for residential purpose and fifth or sixth floor as terrace house or pent house, which, sometime, is an illegal construction.

For buildings beyond this, raft foundation or other type of foundation is used. As far as raft is concerned, it has good resistant to earthquake forces. The raft provides resistant to soil movement and therefore shear developed is resisted by huge concrete mass in the form of raft. However, in case of individual footings, soil movement is comparatively is easy and this earth movement causes tilting of building due to differential settlement of the soil-foundation system causing building to collapse, mainly due to unequal settlement. If this earth movement and earth/soil shaking could be resisted by some means, probably earth may move or vibrate but the soil-foundation system may resist these forces, minimizing possibility of collapse of structure all of sudden.

Hidden beams have been suggested by Deodhar and Dube. More studies have been carried by Deodhar. He has also given various locations where these hidden beams can be provided. However, they are effective in case of soft story. Further they resist movement of soft and other stories and minimizes possibility of sudden collapse of the structure. However, in case of soil movement, during earthquakes of small magnitude / intensity but of large duration or of large magnitude / intensity but of small time duration, these hidden beams may not be effective to that extent. Further, these hidden beams may be effective for high-rise / tall buildings where Raft / Mat foundations is provided. But in case of low-rise buildings of height 12 to 14 or 15 meter having 5 to 6 story construction with a soft story for parking purpose, having isolated or combined footing type of foundation, these hidden beam may not be effective to a considerable extent.

This section of the article is only available for our subscribers. Please click here to subscribe to a subscription plan to view this part of the article.

Sela Tunnel Project - Overcoming The Impossible
The responsibility for construction and maintenance of Balipara-Charduar-Tawang (BCT) Road has been entrusted to Border Roads Organisation (BRO). The 317.520 km long road connects West Kameng and Tawang districts of Arunachal Pradesh to the rest

Read more ...

Slurry TBM ‘Channel Express’ launched by CRCHI for working in Water Supply Tunnels in Singapore
On February 1, 2023, CRCHI attended the launching ceremony of its Slurry TBM ‘Channel Express’. It will be used in the construction of key water supply tunnel project TWRP Pipeline Contract 1 in Singapore where it will bore 1.6km with the inner diameter

Read more ...

China’s Largest TBM - With Panda Face Emerges From Tunnel
On 12 December 2022 ‘Jinxiu’ - China’s largest EPB TBM developed by CRCHI - marked the first smooth breakthrough of the Jinxiu Tunnel, a key control project of the Chengdu-Zigong high-speed railway. Jinxiu is China’s largest diameter EPB TBM with

Read more ...

STRUCINSPECT Technology Transforms Inspection of Los Angeles Metro Tunnel Network
With drones, multispectral optics, and AI, Austrian joint venture transforms tunnel inspection in the US. The world’s first infrastructure lifecycle hub taps the rapidly growing global market for infrastructure inspections. The remarkable thing about

Read more ...

CRCHI showcases total solutions of Underground Engineering Equipment
China Railway Construction Heavy Industry Corporation Limited (CRCHI) brought the whole industry chain products and solutions to bauma CONEXPO INDIA 2023. CRCHI exhibited TBMs, drilling and blasting method equipment, cotton pickers, and other

Read more ...

Sandvik sets up new factory; hands over first ‘made in India’ tunnelling jumbo to KSR Group, Hyderabad
In a historic event held on 30th January, 2023 Sandvik proudly presented the key of the first ‘made in India’ DT820 Tunnelling Jumbo to Mrs. and Mr. Koneru of KSR Group, Hyderabad. The machine was rolled out from Sandvik’s newly set-up state-of-the-art

Read more ...

CRCHI Slurry TBM ‘Avni’ Helps Make a Breakthrough in Bangalore Metro Project
The 6.6m Slurry TBM developed by CRCHI exited the tunnel at Vellara Station, Phase II of Bangalore Metro in India, becoming the first TBM to complete the breakthrough for the whole line of the project. Avni is one of the four slurry TBMs provided by CRCHI

Read more ...

The Bolter Miner - A Technology Revolution for Roadway Development in Underground Coal Mining
In India, coal is still the primary source of energy; over the past few years, there has been quantum jump in coal production level, but it was mostly due to the high percentage share from the opencast sector. The country is witnessing a fast

Read more ...

CRCHI emerges as provider of total underground engineering equipment and solutions
China Railway Construction Heavy Industry Corporation Limited (CRCHI) showcased its comprehensive range of equipment and products at bauma that included solutions for the whole industry chain in the field of

Read more ...

Herrenknecht AG wins bauma Innovation Award 2022 for development of continuous tunnelling
Herrenknecht AG won the highly coveted award bauma Innovation Award 2022 in the category “Machine Technology” for the new development of continuous tunnelling. The award was given for the next innovation boost in the mechanized

Read more ...

The Genesis of Underground Engineering
Regardless of the tunnelling technology used, tunnel designers decide the future success or failure at an early project stage. In fact, designers are the real managers of tunnel construction. The choice of design together with selected contract model is

Read more ...

Managing Geological Complexity in BVC and PAC of Tehri PSP, India - A case study
Tehri hydroelectric project is located on the left bank of River Bhagirathi in the state of Uttarakhand. Tehri Pumped Storage Project (PSP) comprising 4 Nos of reversible pump-turbine units of 250 MW each, involves construction of an underground Machine Hall

Read more ...

TBM driving under low overburden by adopting innovative methodology
TBM mining in urban areas particularly under low overburden (less than 0.5D, D = tunnel Dia) is a big challenge to design team as well as execution team. While working in a Lucknow metro project, the metro authorities encountered a stretch where TBM had to cross

Read more ...

Tunnel Ventilation System Basic Concepts and Designing Principles
The term ventilation combines several functions such as smoke extraction, pollution ventilation, and ventilation for environmental purpose. The design of a ventilation system is usually based on three scenarios: During construction: to provide external

Read more ...

CRCHI Mega Slurry TBM ‘Jinghua’ Assists the First Tunnel Section Breakthrough of Beijing East Sixth Ring Road Reconstruction Project
In September 2022, the Beijing East Sixth Ring Road Reconstruction Project reported another good news: the CRCHI mega slurry TBM ‘Jinghua’ smoothly reached the intermediate air shaft, marking the project’s achievement. The maximum excavation diameter

Read more ...

TERRATEC EPBMs ready to tackle Kanpur Metro’s 1st Underground Section in India
TERRATEC celebrated the successful site acceptance testing of two 6.52m diameter Earth Pressure Balance Tunnel Boring Machines (EPBMs) for Uttar Pradesh Metro Rail Corporation (UPMRC) for Corridor-1 of Kanpur MRTS Project (KNPCC-05) in India. The two 6.52m

Read more ...

Tunnelling Asia 2022 - International Conference on Underground Space
Tunnelling Asia 2022, organized by TAI, which took place in Mumbai during 27th and 28th June, saw a huge gathering of delegates/engineers from all around the world. The theme of the conference: ‘Underground Space: Need of the Day’ focused on

Read more ...

Hydraulic Heave Failure Mitigation Approach for the construction of the Deepest Metro Ventilation and Egress Shaft in India
Dr. Lakshmana Rao Mantri, Assistant General Manager (Designs), and Satya Narayan Kunwar, Project Manager, AFCONS Infrastructure Ltd. , discuss the design and construction challenges of constructing India’s deepest underground metro ventilation

Read more ...

Creating Zero-Carbon Tunnels
Despite a daunting timeline set by the Paris Accord, zero-carbon tunnels are within reach, provided the right solutions are implemented. Er. Vasileios (Bill) Paoulos, CMT, CMRL, L&T Construction Heavy Civil Infrastructure

Read more ...

Readily Biodegradable Soil Conditioning Foaming Agents - A New Technology
Mike A. Sposetti, Global Technical Manager TBM, Underground Construction, Master Builders Solution, Malta, and Manish Gautam, Product Segment Manager - UGC TBM Tunneling Projects, Master Builders Solution, Mumbai, discuss how readily biodegradable

Read more ...